# -*- coding: utf-8 -*-

""" Sahana Eden Common Alerting Protocol (CAP) Model

    @copyright: 2009-2021 (c) Sahana Software Foundation
    @license: MIT

    Permission is hereby granted, free of charge, to any person
    obtaining a copy of this software and associated documentation
    files (the "Software"), to deal in the Software without
    restriction, including without limitation the rights to use,
    copy, modify, merge, publish, distribute, sublicense, and/or sell
    copies of the Software, and to permit persons to whom the
    Software is furnished to do so, subject to the following
    conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
    OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
    HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
    WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
    OTHER DEALINGS IN THE SOFTWARE.
"""

__all__ = ("CAPAlertModel",
           "CAPInfoModel",
           "CAPAreaModel",
           "CAPResourceModel",
           "CAPWarningPriorityModel",
           "CAPHistoryModel",
           "CAPAlertingAuthorityModel",
           "CAPMessageModel",
           "cap_alert_is_template",
           "cap_rheader",
           "cap_history_rheader",
           "cap_alert_list_layout",
           "cap_expirydate",
           "cap_sendername",
           "cap_ImportAlert",
           "cap_AssignArea",
           "cap_AreaRepresent",
           "cap_CloneAlert",
           "cap_AlertProfileWidget",
           )

import datetime
import os

from collections import OrderedDict
from io import StringIO
from urllib import request as urllib2
from urllib.error import HTTPError, URLError
from uuid import uuid4

from gluon import *
from gluon.storage import Storage

from ..s3 import *
from s3layouts import S3PopupLink

OIDPATTERN = r"^[^,<&\s]+$"

# =============================================================================
def get_cap_options():
    """
        Common categories of the CAP model

        @returns: dict of dicts {type: {key: label, ...}, ...}
    """

    T = current.T

    cap_options = {}

    # List of Incident Categories -- copied from irs module <--
    # @ToDo: Switch to using event_incident_type
    #
    # - Keys are based on the Canadian ems.incident hierarchy, with a
    #   few extra general versions added to 'other'
    # - Values are meant for end-users, so can be customised as-required
    # - Entries can be hidden from user view in the controller.
    # - Additional sets of 'translations' can be added to the tuples.
    #
    # NB It is important that the meaning of these entries is not changed
    #    as otherwise this hurts our ability to do synchronisation
    #
    cap_options["incident_types"] = {
        "accident": T("Accident"),
        "animalHealth.animalDieOff": T("Animal Die Off"),
        "animalHealth.animalFeed": T("Animal Feed"),
        "aviation.aircraftCrash": T("Aircraft Crash"),
        "aviation.aircraftHijacking": T("Aircraft Hijacking"),
        "aviation.airportClosure": T("Airport Closure"),
        "aviation.airspaceClosure": T("Airspace Closure"),
        "aviation.noticeToAirmen": T("Notice to Airmen"),
        "aviation.spaceDebris": T("Space Debris"),
        "civil.demonstrations": T("Demonstrations"),
        "civil.dignitaryVisit": T("Dignitary Visit"),
        "civil.displacedPopulations": T("Displaced Populations"),
        "civil.emergency": T("Civil Emergency"),
        "civil.looting": T("Looting"),
        "civil.publicEvent": T("Public Event"),
        "civil.riot": T("Riot"),
        "civil.volunteerRequest": T("Volunteer Request"),
        "crime": T("Crime"),
        "crime.bomb": T("Bomb"),
        "crime.bombExplosion": T("Bomb Explosion"),
        "crime.bombThreat": T("Bomb Threat"),
        "crime.dangerousPerson": T("Dangerous Person"),
        "crime.drugs": T("Drugs"),
        "crime.homeCrime": T("Home Crime"),
        "crime.illegalImmigrant": T("Illegal Immigrant"),
        "crime.industrialCrime": T("Industrial Crime"),
        "crime.poisoning": T("Poisoning"),
        "crime.retailCrime": T("Retail Crime"),
        "crime.shooting": T("Shooting"),
        "crime.stowaway": T("Stowaway"),
        "crime.terrorism": T("Terrorism"),
        "crime.vehicleCrime": T("Vehicle Crime"),
        "fire": T("Fire"),
        "fire.forestFire": T("Forest Fire"),
        "fire.hotSpot": T("Hot Spot"),
        "fire.industryFire": T("Industry Fire"),
        "fire.smoke": T("Smoke"),
        "fire.urbanFire": T("Urban Fire"),
        "fire.wildFire": T("Wild Fire"),
        "flood": T("Flood"),
        "flood.damOverflow": T("Dam Overflow"),
        "flood.flashFlood": T("Flash Flood"),
        "flood.highWater": T("High Water"),
        "flood.overlandFlowFlood": T("Overland Flow Flood"),
        # Added for BT:
        "flood.riverineFlood": T("Riverine Flood"),
        "flood.tsunami": T("Tsunami"),
        "geophysical.avalanche": T("Avalanche"),
        "geophysical.earthquake": T("Earthquake"),
        "geophysical.lahar": T("Lahar"),
        "geophysical.landslide": T("Landslide"),
        "geophysical.magneticStorm": T("Magnetic Storm"),
        "geophysical.meteorite": T("Meteorite"),
        "geophysical.pyroclasticFlow": T("Pyroclastic Flow"),
        "geophysical.pyroclasticSurge": T("Pyroclastic Surge"),
        "geophysical.volcanicAshCloud": T("Volcanic Ash Cloud"),
        "geophysical.volcanicEvent": T("Volcanic Event"),
        "hazardousMaterial": T("Hazardous Material"),
        "hazardousMaterial.biologicalHazard": T("Biological Hazard"),
        "hazardousMaterial.chemicalHazard": T("Chemical Hazard"),
        "hazardousMaterial.explosiveHazard": T("Explosive Hazard"),
        "hazardousMaterial.fallingObjectHazard": T("Falling Object Hazard"),
        "hazardousMaterial.infectiousDisease": T("Infectious Disease (Hazardous Material)"),
        "hazardousMaterial.poisonousGas": T("Poisonous Gas"),
        "hazardousMaterial.radiologicalHazard": T("Radiological Hazard"),
        "health.disease": T("Disease"),
        "health.infectiousDisease": T("Infectious Disease"),
        "health.infestation": T("Infestation"),
        "ice.iceberg": T("Iceberg"),
        "ice.icePressure": T("Ice Pressure"),
        "ice.rapidCloseLead": T("Rapid Close Lead"),
        "ice.specialIce": T("Special Ice"),
        "marine.marineSecurity": T("Marine Security"),
        "marine.nauticalAccident": T("Nautical Accident"),
        "marine.nauticalHijacking": T("Nautical Hijacking"),
        "marine.portClosure": T("Port Closure"),
        "marine.specialMarine": T("Special Marine"),
        "meteorological.blizzard": T("Blizzard"),
        "meteorological.blowingSnow": T("Blowing Snow"),
        "meteorological.drought": T("Drought"),
        "meteorological.dustStorm": T("Dust Storm"),
        "meteorological.fog": T("Fog"),
        "meteorological.freezingDrizzle": T("Freezing Drizzle"),
        "meteorological.freezingRain": T("Freezing Rain"),
        "meteorological.freezingSpray": T("Freezing Spray"),
        "meteorological.hail": T("Hail"),
        "meteorological.hurricane": T("Hurricane"),
        "meteorological.rainFall": T("Rain Fall"),
        "meteorological.snowFall": T("Snow Fall"),
        "meteorological.snowSquall": T("Snow Squall"),
        "meteorological.squall": T("Squall"),
        "meteorological.stormSurge": T("Storm Surge"),
        "meteorological.thunderstorm": T("Thunderstorm"),
        "meteorological.tornado": T("Tornado"),
        "meteorological.tropicalStorm": T("Tropical Storm"),
        "meteorological.waterspout": T("Waterspout"),
        "meteorological.winterStorm": T("Winter Storm"),
        "missingPerson": T("Missing Person"),
        # http://en.wikipedia.org/wiki/Amber_Alert
        "missingPerson.amberAlert": T("Child Abduction Emergency"),
        "missingPerson.missingVulnerablePerson": T("Missing Vulnerable Person"),
        # http://en.wikipedia.org/wiki/Silver_Alert
        "missingPerson.silver": T("Missing Senior Citizen"),
        "publicService.emergencySupportFacility": T("Emergency Support Facility"),
        "publicService.emergencySupportService": T("Emergency Support Service"),
        "publicService.schoolClosure": T("School Closure"),
        "publicService.schoolLockdown": T("School Lockdown"),
        "publicService.serviceOrFacility": T("Service or Facility"),
        "publicService.transit": T("Transit"),
        "railway.railwayAccident": T("Railway Accident"),
        "railway.railwayHijacking": T("Railway Hijacking"),
        "roadway.bridgeClosure": T("Bridge Closed"),
        "roadway.hazardousRoadConditions": T("Hazardous Road Conditions"),
        "roadway.roadwayAccident": T("Road Accident"),
        "roadway.roadwayClosure": T("Road Closed"),
        "roadway.roadwayDelay": T("Road Delay"),
        "roadway.roadwayHijacking": T("Road Hijacking"),
        "roadway.roadwayUsageCondition": T("Road Usage Condition"),
        "roadway.trafficReport": T("Traffic Report"),
        "temperature.arcticOutflow": T("Arctic Outflow"),
        "temperature.coldWave": T("Cold Wave"),
        "temperature.flashFreeze": T("Flash Freeze"),
        "temperature.frost": T("Frost"),
        "temperature.heatAndHumidity": T("Heat and Humidity"),
        "temperature.heatWave": T("Heat Wave"),
        "temperature.windChill": T("Wind Chill"),
        "wind.galeWind": T("Gale Wind"),
        "wind.hurricaneForceWind": T("Hurricane Force Wind"),
        "wind.stormForceWind": T("Storm Force Wind"),
        "wind.strongWind": T("Strong Wind"),
        "other.buildingCollapsed": T("Building Collapsed"),
        "other.peopleTrapped": T("People Trapped"),
        "other.powerFailure": T("Power Failure"),
    }

    # CAP alert Status Code (status)
    cap_options["alert_status"] = OrderedDict([
        ("Actual", T("Actual - actionable by all targeted recipients")),
        ("Exercise", T("Exercise - only for designated participants (decribed in note)")),
        ("System", T("System - for internal functions")),
        ("Test", T("Test - testing, all recipients disregard")),
        ("Draft", T("Draft - not actionable in its current form")),
    ])

    # CAP alert message type (msgType)
    # NB AllClear is not in msgType as of CAP 1.2, but they target to move it
    #    to msgType instead of responseType in CAP 2.0
    cap_options["msg_types"] = OrderedDict([
        ("Alert", T("Alert: Initial information requiring attention by targeted recipients")),
        ("Update", T("Update: Update and supercede earlier message(s)")),
        ("Cancel", T("Cancel: Cancel earlier message(s)")),
        ("Ack", T("Ack: Acknowledge receipt and acceptance of the message(s)")),
        ("Error", T("Error: Indicate rejection of the message(s)")),
        #("AllClear", T("AllClear - The subject event no longer poses a threat")),
    ])

    # CAP alert scope
    cap_options["scopes"] = OrderedDict([
        ("Public", T("Public - unrestricted audiences")),
        ("Restricted", T("Restricted - to users with a known operational requirement (described in restriction)")),
        ("Private", T("Private - only to specified addresses (mentioned as recipients)"))
    ])

    # CAP info categories
    cap_options["categories"] = OrderedDict([
        ("Geo", T("Geo - Geophysical (inc. landslide)")),
        ("Met", T("Met - Meteorological (inc. flood)")),
        ("Safety", T("Safety - General emergency and public safety")),
        ("Security", T("Security - Law enforcement, military, homeland and local/private security")),
        ("Rescue", T("Rescue - Rescue and recovery")),
        ("Fire", T("Fire - Fire suppression and rescue")),
        ("Health", T("Health - Medical and public health")),
        ("Env", T("Env - Pollution and other environmental")),
        ("Transport", T("Transport - Public and private transportation")),
        ("Infra", T("Infra - Utility, telecommunication, other non-transport infrastructure")),
        ("CBRNE", T("CBRNE - Chemical, Biological, Radiological, Nuclear or High-Yield Explosive threat or attack")),
        ("Other", T("Other - Other events")),
    ])

    # CAP info response type
    cap_options["response_types"] = OrderedDict([
        ("Shelter", T("Shelter - Take shelter in place or per instruction")),
        ("Evacuate", T("Evacuate - Relocate as instructed in the instruction")),
        ("Prepare", T("Prepare - Make preparations per the instruction")),
        ("Execute", T("Execute - Execute a pre-planned activity identified in instruction")),
        ("Avoid", T("Avoid - Avoid the subject event as per the instruction")),
        ("Monitor", T("Monitor - Attend to information sources as described in instruction")),
        ("Assess", T("Assess - Evaluate the information in this message.")),
        ("AllClear", T("AllClear - The subject event no longer poses a threat")),
        ("None", T("None - No action recommended")),
    ])

    # CAP info urgency
    cap_options["urgency"] = OrderedDict([
        ("Immediate", T("Immediate - Response action should be taken immediately")),
        ("Expected", T("Expected - Response action should be taken soon (within next hour)")),
        ("Future", T("Future - Responsive action should be taken in the near future")),
        ("Past", T("Past - Responsive action is no longer required")),
        ("Unknown", T("Unknown")),
    ])

    # CAP info severity
    cap_options["severity"] = OrderedDict([
        ("Extreme", T("Extreme - Extraordinary threat to life or property")),
        ("Severe", T("Severe - Significant threat to life or property")),
        ("Moderate", T("Moderate - Possible threat to life or property")),
        ("Minor", T("Minor - Minimal to no known threat to life or property")),
        ("Unknown", T("Severity unknown")),
    ])

    # CAP info certainty
    cap_options["certainty"] = OrderedDict([
        ("Observed", T("Observed: determined to have occurred or to be ongoing")),
        ("Likely", T("Likely (p > ~50%)")),
        ("Possible", T("Possible but not likely (p <= ~50%)")),
        ("Unlikely", T("Unlikely - Not expected to occur (p ~ 0)")),
        ("Unknown", T("Certainty unknown")),
    ])

    return cap_options

# =============================================================================
class CAPAlertModel(S3Model):
    """ Model for the cap:alert container object """

    names = ("cap_alert",
             "cap_alert_ack",
             "cap_alert_id",
             "cap_alert_represent",
             "cap_alert_onapprove",
             )

    def model(self):

        T = current.T

        db = current.db
        settings = current.deployment_settings
        crud_strings = current.response.s3.crud_strings

        define_table = self.define_table
        set_method = self.set_method

        cap_options = get_cap_options()

        incident_types = cap_options["incident_types"]
        status_opts = cap_options["alert_status"]
        msg_types = cap_options["msg_types"]
        scopes = cap_options["scopes"]

        # ---------------------------------------------------------------------
        # Alerts
        #
        tablename = "cap_alert"
        define_table(tablename,
                     Field("is_template", "boolean",
                           default = False,
                           readable = False,
                           writable = True,
                           ),
                     self.event_type_id(
                        ondelete = "SET NULL",
                        label = T("Event Type"),
                        comment = DIV(_class="tooltip",
                                      _title="%s|%s" % (T("Event Type of the alert message"),
                                                        T("Event Type is classification of event."),
                                                        ),
                                      ),
                        script = '''
$.filterOptionsS3({
    'trigger':'event_type_id',
    'target':'template_id',
    'lookupPrefix': 'cap',
    'lookupResource':'template',
    'fncRepresent': function(record,PrepResult){return record.template_title},
    'optional': true,
    'lookupURL': S3.Ap.concat('/cap/template.json?~.event_type_id=')
})''',
                        ),
                     Field("template_id", "reference cap_alert",
                           label = T("Template"),
                           ondelete = "SET NULL",
                           represent = self.template_represent,
                           requires = IS_EMPTY_OR(
                                         IS_ONE_OF(db, "cap_alert.id",
                                                   self.template_represent,
                                                   filterby = "is_template",
                                                   filter_opts = (True, ),
                                                   )),
                           comment = T("Apply a template"),
                           ),
                     Field("template_title",
                           label = T("Template Title"),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("Template Title"),
                                                           T("Title for the template, to indicate to which event this template is related to"),
                                                           ),
                                         ),
                           ),
                     Field("template_settings", "text",
                           default = "{}",
                           readable = False,
                           ),
                     Field("identifier", unique=True, length=255,
                           default = self.generate_identifier,
                           label = T("Identifier"),
                           requires = [IS_LENGTH(255),
                                       IS_MATCH(OIDPATTERN,
                                                error_message = T("Cannot be empty and Must not include spaces, commas, or restricted characters (< and &)."),
                                                ),
                                       ],
                           # Dont Allow to change the identifier
                           readable = False,
                           writable = False,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("A unique identifier of the alert message"),
                                                             T("A number or string uniquely identifying this message, assigned by the sender. Must not include spaces, commas or restricted characters (< and &)."),
                                                             ),
                                         ),
                           ),
                     # @ToDo: Switch to using event_incident_type_id
                     Field("incidents", "list:string",
                           label = T("Incidents"),
                           represent = S3Represent(options = incident_types,
                                                   multiple = True,
                                                   ),
                           requires = IS_EMPTY_OR(
                                        IS_IN_SET(incident_types,
                                                  multiple = True,
                                                  sort = True,
                                                  )),
                           widget = S3MultiSelectWidget(selectedList = 10),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("A list of incident(s) referenced by the alert message"),
                                                           T("Used to collate multiple messages referring to different aspects of the same incident. If multiple incident identifiers are referenced, they SHALL be separated by whitespace.  Incident names including whitespace SHALL be surrounded by double-quotes."),
                                                           ),
                                         ),
                           ),
                     Field("sender",
                           label = T("Sender"),
                           default = self.generate_sender,
                           requires = IS_MATCH(OIDPATTERN,
                                               error_message=T("Cannot be empty and Must not include spaces, commas, or restricted characters (< and &)."),
                                               ),
                           readable = False,
                           writable = False,
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The identifier of the sender of the alert message"),
                                                           T("This is guaranteed by assigner to be unique globally; e.g., may be based on an Internet domain name. Must not include spaces, commas or restricted characters (< and &)."),
                                                           ),
                                         ),
                           ),
                     s3_datetime("sent",
                                 default = "now",
                                 writable = False,
                                 ),
                     Field("status",
                           default = "Draft",
                           label = T("Status"),
                           represent = S3Represent(options=status_opts),
                           requires = IS_IN_SET(status_opts),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("Denotes the appropriate handling of the alert message"),
                                                           T("See options."),
                                                           ),
                                         ),
                           ),
                     Field("msg_type",
                           label = T("Message Type"),
                           default = "Alert",
                           #represent = S3Represent(options=msg_types),
                           requires = IS_IN_SET(msg_types),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The nature of the alert message"),
                                                           T("See options."),
                                                           ),
                                         ),
                           ),
                     Field("source",
                           label = T("Source"),
                           default = self.generate_source,
                           readable = False,
                           writable = False,
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The text identifying the source of the alert message"),
                                                           T("The particular source of this alert; e.g., an operator or a specific device."),
                                                           ),
                                         ),
                           ),
                     Field("scope",
                           label = T("Scope"),
                           requires = IS_EMPTY_OR(IS_IN_SET(scopes)),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("Denotes the intended distribution of the alert message"),
                                                           T("Who is this alert for?"),
                                                           ),
                                         ),
                           ),
                     # Text describing the restriction for scope=restricted
                     Field("restriction", "text",
                           label = T("Restriction"),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The text describing the rule for limiting distribution of the restricted alert message"),
                                                           T("Used when scope is 'Restricted'."),
                                                           ),
                                         ),
                           ),
                     # TODO introduce a separate "recipients"-field (list:reference pr_pentity)
                     #      and translate it onaccept into addresses
                     Field("addresses", "list:string",
                           label = T("Recipients"),
                           requires = IS_EMPTY_OR(
                                        IS_IN_SET(get_cap_alert_addresses_opts(),
                                                  multiple = True,
                                                  sort = True,
                                                  )
                                        ),
                           #represent = S3Represent(lookup = "pr_group",
                           #                        fields = ["name"],
                           #                        multiple = True,
                           #                        ),
                           widget = S3MultiSelectWidget(),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The group listing of intended recipients of the alert message"),
                                                           T("Required when scope is 'Private', optional when scope is 'Public' or 'Restricted'. Each recipient shall be identified by an identifier or an address."),
                                                           ),
                                         ),
                           ),
                     Field("codes", "list:string",
                           default = settings.get_cap_codes(),
                           label = T("Codes"),
                           represent = list_string_represent,
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("Codes for special handling of the message"),
                                                           T("Any user-defined flags or special codes used to flag the alert message for special handling."),
                                                           ),
                                         ),
                           ),
                     Field("note", "text",
                           label = T("Note"),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The text describing the purpose or significance of the alert message"),
                                                           T("The message note is primarily intended for use with status 'Exercise' and message type 'Error'"),
                                                           ),
                                         ),
                           ),
                     # Alert references:
                     # - using "text" field type because alert references could be
                     #   many and thus easily exceed the limit for string fields
                     # - @todo: consider to use a list:reference instead
                     Field("reference", "text",
                           label = T("Reference"),
                           writable = False,
                           readable = False,
                           # @todo: implement a suitable representation (if using list:reference)
                           #represent = S3Represent(lookup = tablename,
                           #                        fields = ["msg_type", "sent", "sender"],
                           #                        field_sep = " - ",
                           #                        multiple = True,
                           #                        ),
                           # @todo: implement a widget to select from existing alerts
                           #widget = S3ReferenceWidget(table,
                           #                           one_to_many = True,
                           #                           allow_create = False,
                           #                           ),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The group listing identifying earlier message(s) referenced by the alert message"),
                                                           T("The extended message identifier(s) (in the form sender,identifier,sent) of an earlier CAP message or messages referenced by this one."),
                                                           ),
                                         ),
                           ),
                     # To record when the alert was approved
                     s3_datetime("approved_on",
                                 readable = False,
                                 writable = False,
                                 ),
                     # To distinguish internally vs. externally generated alerts:
                     Field("external", "boolean",
                           # Set to False in controller for interactive input:
                           default = True,
                           readable = False,
                           writable = False,
                           ),
                     *s3_meta_fields())

        # Components
        self.add_components(tablename,
                            cap_area = "alert_id",
                            cap_area_location = {"name": "location",
                                                 "joinby": "alert_id",
                                                 },
                            cap_area_tag = {"name": "tag",
                                            "joinby": "alert_id",
                                            },
                            cap_info = "alert_id",
                            cap_info_parameter = "alert_id",
                            cap_resource = "alert_id",
                            )

        # Resource-specific REST Methods
        set_method("cap", "alert",
                   method = "import_feed",
                   action = cap_ImportAlert,
                   )

        set_method("cap", "alert",
                   method = "assign",
                   action = cap_AssignArea,
                   )

        set_method("cap", "alert",
                   method = "clone",
                   action = cap_CloneAlert,
                   )

        # List Fields
        list_fields = ["event_type_id",
                       "msg_type",
                       (T("Sent"), "sent"),
                       "info.headline",
                       "info.sender_name",
                       ]

        # Filter Widgets
        filter_widgets = [
            S3TextFilter(["identifier",
                          "sender",
                          "incidents",
                          "cap_info.headline",
                          "cap_info.event",
                          ],
                         label = T("Search"),
                         comment = T("Search for an Alert by sender, incident, headline or event."),
                         ),
            S3OptionsFilter("info.category",
                            label = T("Category"),
                            options = cap_options["categories"],
                            hidden = True,
                            ),
            S3OptionsFilter("info.event_type_id",
                            hidden = True,
                            ),
            S3OptionsFilter("scope",
                            hidden = True,
                            ),
            S3OptionsFilter("info.priority",
                            hidden = True,
                            ),
            S3LocationFilter("location.location_id",
                             label = T("Location(s)"),
                             # options = gis.get_countries().keys(),
                             hidden = True,
                             ),
            S3OptionsFilter("info.language",
                            label = T("Language"),
                            hidden = True,
                            ),
            ]

        # Fields to include in Notifications
        notify_fields = [(T("Identifier"), "identifier"),
                         (T("Date"), "sent"),
                         (T("Status"), "status"),
                         (T("Message Type"), "msg_type"),
                         (T("Source"), "source"),
                         (T("Scope"), "scope"),
                         (T("Restriction"), "restriction"),
                         (T("Category"), "info.category"),
                         (T("Event"), "info.event_type_id"),
                         (T("Response type"), "info.response_type"),
                         (T("Priority"), "info.priority"),
                         (T("Urgency"), "info.urgency"),
                         (T("Severity"), "info.severity"),
                         (T("Certainty"), "info.certainty"),
                         (T("Effective"), "info.effective"),
                         (T("Expires at"), "info.expires"),
                         (T("Sender's name"), "info.sender_name"),
                         (T("Headline"), "info.headline"),
                         (T("Description"), "info.description"),
                         (T("Instruction"), "info.instruction"),
                         (T("Contact information"), "info.contact"),
                         (T("URL"), "info.web"),
                         (T("Area Description"), "area.name"),
                         ]

        # Table Configuration
        # TODO: if an alert is already-published, edit should create
        #       a new "Update" alert instead of modifying the original
        #       => implement special CRUD method handler for that
        self.configure(tablename,
                       context = {"location": "location.location_id",
                                  },
                       create_onaccept = self.alert_create_onaccept,
                       deduplicate = S3Duplicate(primary = ("identifier", ),
                                                 secondary = ("sender", ),
                                                 ),
                       filter_widgets = filter_widgets,
                       list_fields = list_fields,
                       list_layout = cap_alert_list_layout,
                       # Required Fields
                       mark_required = ("scope",),
                       notify_fields = notify_fields,
                       onapprove = self.alert_onapprove,
                       onvalidation = self.alert_onvalidation,
                       # Order with most recent Alert first
                       orderby = "cap_alert.sent desc",
                       )

        # CRUD Strings
        if crud_strings["cap_template"]:
            crud_strings[tablename] = crud_strings["cap_template"]
        else:
            crud_strings[tablename] = Storage(
                label_create = T("Create Alert"),
                title_display = T("Alert Details"),
                title_list = T("Alerts"),
                title_update = T("Edit Alert"),
                title_upload = T("Import Alerts"),
                label_list_button = T("List Alerts"),
                label_delete_button = T("Delete Alert"),
                msg_record_created = T("Alert created"),
                msg_record_modified = T("Alert modified"),
                msg_record_deleted = T("Alert deleted"),
                msg_list_empty = T("No alerts to show"),
                )

        # Reference representation
        alert_represent = S3Represent(lookup = tablename,
                                      fields = ["msg_type", "sent", "sender"],
                                      field_sep = " - ",
                                      )

        # Reusable Field
        alert_id = S3ReusableField("alert_id", "reference %s" % tablename,
                                   comment = T("The alert message containing this information"),
                                   label = T("Alert"),
                                   ondelete = "CASCADE",
                                   represent = alert_represent,
                                   requires = IS_EMPTY_OR(
                                                IS_ONE_OF(db, "cap_alert.id",
                                                          alert_represent,
                                                          )),
                                   )

        # ---------------------------------------------------------------------
        # Acknowledgement Table for CAP Alert
        #
        tablename = "cap_alert_ack"
        define_table(tablename,
                     alert_id(readable = False,
                              writable = False,
                              ),
                     # Use this when location intersect filter is supported:
                     self.gis_location_id(
                        readable = False,
                        writable = False,
                        ),
                     s3_datetime("acknowlegded_on",
                                 label = T("Acknowledged On"),
                                 default = "now",
                                 requires = IS_NOT_EMPTY(),
                                 ),
                     Field("acknowledged_by",
                           label = T("Acknowledged By"),
                           requires = IS_NOT_EMPTY(),
                           ),
                     s3_comments(),
                     *s3_meta_fields())

        # CRUD Strings
        crud_strings[tablename] = Storage(
            label_create = T("Add Acknowledgement"),
            title_display = T("Alert Acknowledgement"),
            title_list = T("Alert Acknowledgements"),
            title_update = T("Edit Acknowledgement"),
            subtitle_list = T("List Alert Acknowledgements"),
            label_list_button = T("List Alert Acknowledgements"),
            label_delete_button = T("Delete Acknowledgement"),
            msg_record_created = T("Acknowledgement added"),
            msg_record_modified = T("Acknowledgement updated"),
            msg_record_deleted = T("Acknowledgement deleted"),
            msg_list_empty = T("No Acknowledgements currently received for this alert"),
            )

        # ---------------------------------------------------------------------
        # Pass names back to global scope (s3.*)
        #
        return {"cap_alert_id": alert_id,
                "cap_alert_represent": alert_represent,
                "cap_alert_onapprove": self.alert_onapprove,
                }

    # -------------------------------------------------------------------------
    @staticmethod
    def defaults():
        """
            Return safe defaults in case the model has been deactivated.
        """

        return {"cap_alert_id": S3ReusableField.dummy("alert_id"),
                }

    # -------------------------------------------------------------------------
    @staticmethod
    def generate_identifier():
        """
            Generate an alert identifier for a new (internal) alert

            @returns: a string of the format "urn:oid:<oid>.<date>.<alert_id>"
        """

        db = current.db
        table = db.cap_alert

        # The OID
        # - OID is normally of the form 2.49.0.1.104.xx.(yy)
        # - xx=0 identifies this as OID of the organisation itself
        # - should be changed to xx=1 when it is used in an alert
        oid = current.deployment_settings.get_cap_identifier_oid()
        parts = oid.split(".")
        if len(parts) > 5 and parts[5] == "0":
            parts[5] = "1"
        oid = ".".join(parts)

        # Current date, formatted
        now = datetime.datetime.utcnow().strftime("%Y.%m.%d")

        # Determine the next record ID in the alert table
        row = db().select(table.id,
                          limitby = (0, 1),
                          orderby = ~table.id,
                          ).first()
        next_id = (row.id + 1) if row else 1

        # Format: urn:oid:<oid>.<date>.<alert_id>
        return "urn:oid:%s.%s.%03d" % (oid, now, next_id)

    # -------------------------------------------------------------------------
    @staticmethod
    def generate_sender():
        """
            Generate a sender name for a new (internal) alert
                - use email address of current user

            @returns: the sender name as string
        """

        try:
            user_email = current.auth.user.email
        except AttributeError:
            # Not logged-in
            sender = ""
        else:
            sender = s3_str(user_email)

        return sender

    # -------------------------------------------------------------------------
    @staticmethod
    def generate_source():
        """
            Generate a source designation for a new (internal) alert

            @returns: the message source designation as string
        """
        return "%s@%s" % (current.xml.domain,
                          current.deployment_settings.get_base_public_url(),
                          )

    # -------------------------------------------------------------------------
    @staticmethod
    def alert_onvalidation(form):
        """
            Validate an alert form

            @param form: the FORM
        """

        T = current.T

        form_vars_get = form.vars.get
        if not form_vars_get("is_template"):
            # Actual Alert (not a template)

            scope = form_vars_get("scope")

            # Scope is mandatory
            if not scope:
                form.errors["scope"] = T("'Scope' field is mandatory for actual alerts!")

            ## Scope is mandatory if specifying Recipients
            #if form_vars_get("addresses") and not scope:
            #    form.errors["scope"] = T("'Scope' field mandatory in case using 'Recipients' field")

            # Scope "Private" requires recipients (interactive input only)
            request = current.request
            if scope == "Private" and \
               request.controller == "cap" and request.function == "alert":
                if not form_vars_get("addresses"):
                    form.errors["addresses"] = T("'Recipients' field mandatory in case of 'Private' scope")

            # Scope "Restricted" requires specification of restriction
            elif scope == "Restricted" and not form_vars_get("restriction"):
                form.errors["restriction"] = T("'Restriction' field mandatory in case of 'Restricted' scope")

            # Actual alerts cannot have "Draft" status
            if form_vars_get("status") == "Draft":
                form.errors["status"] = T("Cannot issue 'Draft' alerts!")

    # -------------------------------------------------------------------------
    @staticmethod
    def alert_create_onaccept(form):
        """
            Onaccept-routine for alerts:
                - automatically approve if template

            @param form: the FORM
        """

        form_vars = form.vars
        if form_vars.get("is_template"):

            user = current.auth.user
            if user:
                table = current.s3db.cap_alert
                current.db(table.id == form_vars.id).update(approved_by=user.id)

    # -------------------------------------------------------------------------
    @staticmethod
    def alert_onapprove(record=None):
        """
            On approval of alerts:
                - update the approved_on field
                - notify the record owner of the approval
                - create history entry for the approved record

            @param record: the alert record

            TODO set approved_on even when approval is not required
                 (we want to allow auto-approval for editors)
        """

        if not record:
            return

        alert_id = record["id"]

        # Update approved_on at the time the alert is approved
        if alert_id:

            db = current.db
            table = db.cap_alert
            query = (table.id == alert_id) & \
                    (table.deleted == False)

            # Update approved_on
            utcnow = current.request.utcnow
            db(query).update(approved_on=utcnow, sent=utcnow)

            # Get the record owner
            row = db(query).select(table.id,
                                   table.owned_by_user,
                                   limitby = (0, 1),
                                   ).first()
            owner = row.owned_by_user if row else None

            # Notify the owner of the record about approval
            if owner:
                pe_id = current.auth.s3_user_pe_id(owner)

                settings = current.deployment_settings
                subject = "%s: Alert Approved" % settings.get_system_name_short()
                url = "%s%s" % (settings.get_base_public_url(),
                                URL(c="cap", f="alert", args=[alert_id]),
                                )
                message = current.T("This alert that you requested to review has been approved:\n\n%s") % url
                current.msg.send_by_pe_id(pe_id,
                                          subject,
                                          message,
                                          alert_id = alert_id,
                                          )

            # Record the approved alert in alert history
            clone(current.request, record)

    # -------------------------------------------------------------------------
    @staticmethod
    def template_represent(alert_id, row=None):
        """
            Represent an alert template concisely

            @param alert_id: the alert record ID
            @param row: the alert record (if already loaded)

            @returns: a string representation for the alert ID

            TODO make S3Represent at module level
        """

        if row:
            alert_id = row.id
        elif alert_id:
            db = current.db
            table = db.cap_alert
            row = db(table.id == alert_id).select(table.is_template,
                                                  table.template_title,
                                                  limitby = (0, 1),
                                                  ).first()

        if row:
            if row.is_template:
                # @ToDo: get headline from locale-specific "info" instead?
                repr_str = row.template_title
            else:
                repr_str = current.s3db.cap_alert_represent(alert_id)
        else:
            repr_str = current.messages["NONE"]

        return repr_str

# =============================================================================
class CAPInfoModel(S3Model):

    names = ("cap_info",
             "cap_info_id",
             "cap_info_represent",
             "cap_info_parameter",
             )

    def model(self):

        T = current.T

        db = current.db
        settings = current.deployment_settings
        crud_strings = current.response.s3.crud_strings

        define_table = self.define_table
        configure = self.configure

        cap_options = get_cap_options()

        alert_id = self.cap_alert_id

        # TODO do not modify a deployment setting in the model,
        #      pass as mandatory options s3_language instead
        settings.L10n.extra_codes = [("en-US", "English"),
                                     ("en-CA", "Canadian English"),
                                     ("fr-CA", "Canadian French"),
                                     ]

        # ---------------------------------------------------------------------
        # Info segment of Alert
        #
        tablename = "cap_info"
        define_table(tablename,
                     alert_id(),
                     Field("is_template", "boolean",
                           default = False,
                           readable = False,
                           writable = False,
                           ),
                     Field("template_info_id", "reference cap_info",
                           ondelete = "SET NULL",
                           readable = False,
                           requires = IS_EMPTY_OR(
                                        IS_ONE_OF(db, "cap_info.id",
                                                  CAPAlertModel.template_represent,
                                                  filterby = "is_template",
                                                  filter_opts = (True,),
                                                  )),
                           widget = S3HiddenWidget(),
                           ),
                     Field("template_settings", "text",
                           readable = False,
                           ),
                     s3_language(default = "en-US",
                                 empty = False,
                                 ),
                     Field("category", "list:string", # 1 or more allowed
                           label = T("Category"),
                           represent = S3Represent(options = cap_options["categories"],
                                                   multiple = True,
                                                   ),
                           requires = IS_IN_SET(cap_options["categories"],
                                                multiple = True,
                                                ),
                           widget = S3MultiSelectWidget(selectedList=10),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Denotes the category of the subject event of the alert message"),
                                                             T("You may select multiple categories by holding down control and then selecting the items."),
                                                             ),
                                         ),
                           ),
                     Field("event",
                           label = T("Event"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The text denoting the type of the subject event of the alert message"),
                                                             T("If not specified, will the same as the Event Type."),
                                                             ),
                                         ),
                           ),
                     self.event_type_id(
                        #empty = False,
                        readable = False,
                        ondelete = "SET NULL",
                        label = T("Event Type"),
                        comment = DIV(_class = "tooltip",
                                      _title = "%s|%s" % (T("Event Type of the alert message"),
                                                          T("Event field above is more general. And this Event Type is classification of event. For eg. Event can be 'Terrorist Attack' and Event Type can be either 'Terrorist Bomb Explosion' or 'Terrorist Chemical Waefare Attack'. If not specified, will the same as the Event Type."),
                                                          ),
                                      ),
                        script = '''
$.filterOptionsS3({
    'trigger':'event_type_id',
    'target':'priority',
    'lookupPrefix': 'cap',
    'lookupResource':'warning_priority',
    'lookupKey': 'event_type_id',
    'optional': true
})''',
                        ),
                     Field("response_type", "list:string", # 0 or more allowed
                           label = T("Response Type"),
                           represent = S3Represent(options = cap_options["response_types"],
                                                   multiple = True,
                                                   ),
                           requires = IS_IN_SET(cap_options["response_types"],
                                                multiple = True),
                           widget = S3MultiSelectWidget(selectedList=10),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Denotes the type of action recommended for the target audience"),
                                                             T("Multiple response types can be selected by holding down control and then selecting the items"),
                                                             ),
                                         ),
                           ),
                     self.cap_warning_priority_id(
                         comment = DIV(_class = "tooltip",
                                       _title = "%s|%s" % (T("Priority of the alert message"),
                                                           T("Defines the priority of the alert message. Selection of the priority automatically sets the value for 'Urgency', 'Severity' and 'Certainty'")
                                                           ),
                                       ),
                         ),
                     Field("urgency",
                           label = T("Urgency"),
                           represent = S3Represent(options = cap_options["urgency"],
                                                   ),
                           # Empty For Template, checked onvalidation hook
                           requires = IS_EMPTY_OR(
                                        IS_IN_SET(cap_options["urgency"])),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Urgency"),
                                                             T("Denotes the urgency of the subject event of the alert message"),
                                                             ),
                                         ),
                           ),
                     Field("severity",
                           label = T("Severity"),
                           represent = S3Represent(options = cap_options["severity"],
                                                   ),
                           # Empty For Template, checked onvalidation hook
                           requires = IS_EMPTY_OR(
                                        IS_IN_SET(cap_options["severity"])),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Severity"),
                                                             T("Denotes the severity of the subject event of the alert message"),
                                                             ),
                                         ),
                           ),
                     Field("certainty",
                           label = T("Certainty"),
                           represent = S3Represent(options = cap_options["certainty"],
                                                   ),
                           # Empty For Template, checked onvalidation hook
                           requires = IS_EMPTY_OR(
                                        IS_IN_SET(cap_options["certainty"])),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Certainty"),
                                                             T("Denotes the certainty of the subject event of the alert message"),
                                                             ),
                                         ),
                           ),
                     Field("audience", "text",
                           label = T("Audience"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Audience"),
                                                             T("The intended audience of the alert message"),
                                                             ),
                                         ),
                           ),
                     Field("event_code", "text",
                           label = T("Event Code"),
                           default = settings.get_cap_event_codes(),
                           represent = S3KeyValueWidget.represent,
                           widget = S3KeyValueWidget(),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("A system-specific code identifying the event type of the alert message"),
                                                             T("Any system-specific code for events, in the form of key-value pairs. (e.g., SAME, FIPS, ZIP)."),
                                                             ),
                                         ),
                           ),
                     s3_datetime("effective",
                                 label = T("Effective"),
                                 default = "now",
                                 comment = DIV(_class = "tooltip",
                                               _title = "%s|%s" % (T("The effective time of the information of the alert message"),
                                                                   T("If not specified, the effective time shall be assumed to be the same the time the alert was sent."),
                                                                   ),
                                               ),
                                 ),
                     s3_datetime("onset",
                                 label = T("Onset"),
                                 comment = DIV(_class = "tooltip",
                                               _title = "%s|%s" % (T("Onset"),
                                                                   T("The expected time of the beginning of the subject event of the alert message"),
                                                                   ),
                                               ),
                                 ),
                     s3_datetime("expires",
                                 label = T("Expires at"),
                                 #past = 0,
                                 default = cap_expirydate(),
                                 comment = DIV(_class = "tooltip",
                                               _title = "%s|%s" % (T("The expiry time of the information of the alert message"),
                                                                   T("If this item is not provided, each recipient is free to enforce its own policy as to when the message is no longer in effect."),
                                                                   ),
                                               ),
                                 ),
                     Field("sender_name",
                           label = T("Sender's name"),
                           default = cap_sendername,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The text naming the originator of the alert message"),
                                                             T("The human-readable name of the agency or authority issuing this alert."),
                                                             ),
                                         ),
                           ),
                     Field("headline",
                           label = T("Headline"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The text headline of the alert message"),
                                                             T("A brief human-readable headline.  Note that some displays (for example, short messaging service devices) may only present this headline; it should be made as direct and actionable as possible while remaining short.  160 characters may be a useful target limit for headline length."),
                                                             ),
                                         ),
                           ),
                     Field("description", "text",
                           label = T("Description"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The subject event of the alert message"),
                                                             T("An extended human readable description of the hazard or event that occasioned this message."),
                                                             ),
                                         ),
                           ),
                     Field("instruction", "text",
                           label = T("Instruction"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The recommended action to be taken by recipients of the alert message"),
                                                             T("An extended human readable instruction to targeted recipients.  If different instructions are intended for different recipients, they should be represented by use of multiple information blocks. You can use a different information block also to specify this information in a different language."),
                                                             ),
                                         ),
                           ),
                     Field("contact", "text",
                           label = T("Contact information"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Contact"),
                                                             T("The contact for follow-up and confirmation of the alert message"),
                                                             ),
                                         ),
                           ),
                     Field("web",
                           label = T("URL"),
                           requires = IS_EMPTY_OR(IS_URL()),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("A URL associating additional information with the alert message"),
                                                             T("A full, absolute URI for an HTML page or other text resource with additional or reference information regarding this alert."),
                                                             ),
                                         ),
                           ),
                     #Field("parameter", "text",
                     #      default = settings.get_cap_parameters(),
                     #      label = T("Parameters"),
                     #      represent = S3KeyValueWidget.represent,
                     #      widget = S3KeyValueWidget(),
                     #      comment = DIV(_class = "tooltip",
                     #                    _title = "%s|%s" % (T("A system-specific additional parameter associated with the alert message"),
                     #                                        T("Any system-specific datum, in the form of key-value pairs."),
                     #                                        ),
                     #                    ),
                     #      ),
                     *s3_meta_fields())

        # Components
        self.add_components(tablename,
                            cap_info_parameter = "info_id",
                            cap_resource = "info_id",
                            cap_area = "info_id",
                            )

        # CRUD Form
        crud_form = S3SQLCustomForm("alert_id",
                                    "is_template",
                                    "template_info_id",
                                    # Not used
                                    #"template_settings",
                                    "language",
                                    "category",
                                    "event",
                                    "event_type_id",
                                    "response_type",
                                    "priority",
                                    "urgency",
                                    "severity",
                                    "certainty",
                                    "audience",
                                    "event_code",
                                    "effective",
                                    "onset",
                                    "expires",
                                    "sender_name",
                                    "headline",
                                    "description",
                                    "instruction",
                                    "contact",
                                    "web",
                                    S3SQLInlineComponent(
                                        "info_parameter",
                                        name = "info_parameter",
                                        label = T("Parameter"),
                                        fields = ["name",
                                                  "value",
                                                  "mobile",
                                                  ],
                                        comment = DIV(_class = "tooltip",
                                                      _title = "%s|%s" % (T("A system-specific additional parameter associated with the alert message"),
                                                                          T("Any system-specific datum, in the form of key-value pairs."),
                                                                          ),
                                                      ),
                                        ),
                                    )

        # Table Configuration
        configure(tablename,
                  # TODO: if an alert is already-published, edit should create
                  #       a new "Update" alert instead of modifying the original
                  #       => implement special CRUD method handler for that
                  crud_form = crud_form,
                  deduplicate = self.info_duplicate,
                  # Required Fields
                  mark_required = ("urgency", "severity", "certainty",),
                  onaccept = self.info_onaccept,
                  onvalidation = self.info_onvalidation,
                  )

        # CRUD Strings
        if crud_strings["cap_template_info"]:
            crud_strings[tablename] = crud_strings["cap_template_info"]
        else:
            crud_strings[tablename] = Storage(
                label_create = T("Add alert information"),
                title_display = T("Alert information"),
                title_list = T("Information entries"),
                title_update = T("Update alert information"),
                title_upload = T("Import alert information"),
                subtitle_list = T("Listing of alert information items"),
                label_list_button = T("List information entries"),
                label_delete_button = T("Delete Information"),
                msg_record_created = T("Alert information created"),
                msg_record_modified = T("Alert information modified"),
                msg_record_deleted = T("Alert information deleted"),
                msg_list_empty = T("No alert information to show"),
                )

        # Reference Representation
        info_represent = S3Represent(lookup = tablename,
                                     fields = ["language", "headline"],
                                     field_sep = " - ")

        # Reusable Field
        info_id = S3ReusableField("info_id", "reference %s" % tablename,
                                  label = T("Information Segment"),
                                  ondelete = "CASCADE",
                                  represent = info_represent,
                                  requires = IS_EMPTY_OR(
                                                IS_ONE_OF(db, "cap_info.id",
                                                          info_represent,
                                                          )),
                                  #sortby = "identifier",
                                  )

        # ---------------------------------------------------------------------
        # CAP Info Parameters (Name-Value-Pairs)
        #
        tablename = "cap_info_parameter"
        define_table(tablename,
                     alert_id(),
                     info_id(),
                     Field("name",
                           label = T("Name"),
                           ),
                     Field("value",
                           label = T("Value"),
                           ),
                     Field("mobile", "boolean",
                           default = False,
                           label = T("Mobile"),
                           represent = s3_yes_no_represent,
                           ),
                     *s3_meta_fields())

        # Table Configuration
        configure(tablename,
                  onaccept = self.info_parameter_onaccept,
                  #onvalidation = self.info_parameter_onvalidation,
                  )

        # ---------------------------------------------------------------------
        # Pass names back to global scope (s3.*)
        return {"cap_info_id": info_id,
                "cap_info_represent": info_represent,
                }

    # -------------------------------------------------------------------------
    @staticmethod
    def defaults():
        """
            Return safe defaults in case the model has been deactivated.
        """

        return {}

    # -------------------------------------------------------------------------
    @staticmethod
    def info_onvalidation(form):
        """
            Form validation for info-segments:
                - check for language duplicates
                - for actual alerts: make sure urgency, severity, certainty
                  and category have been specified

            @param form: the FORM
        """

        T = current.T

        itable = current.db.cap_info

        # Check for existing info with the same language
        query = (itable.alert_id == form.request_vars.alert_id) & \
                (itable.language == form.vars.language) & \
                (itable.id != form.request_vars.id)
        other_info = current.db(query).select(itable.id,
                                              limitby=(0, 1),
                                              ).first()

        if other_info:
            form.errors["language"] = T("Please edit already created info segment with same language!")

        form_record = form.record
        if form_record and form_record.is_template == False:

            form_vars = form.vars

            #parameters = json.loads(form_vars.get("parameter"))
            #if parameters:
            #    for parameter in parameters:
            #        if (parameter["key"] and not parameter["value"]) or \
            #           (parameter["value"] and not parameter["key"]):
            #            form.errors["parameter"] = \
            #                current.T("Name-Value Pair is incomplete.")

            if not form_vars.get("urgency"):
                form.errors["urgency"] = T("'Urgency' field is mandatory")
            if not form_vars.get("severity"):
                form.errors["severity"] = T("'Severity' field is mandatory")
            if not form_vars.get("certainty"):
                form.errors["certainty"] = T("'Certainty' field is mandatory")

            if not form_vars.get("category"):
                form.errors["category"] = T("At least one category is required.")

    # -------------------------------------------------------------------------
    @classmethod
    def info_onaccept(cls, form):
        """
            Onaccept-routine for info-segments
                - inherit is_template from alert
                - sanitize and complete input data
                - sync all info-segments of the same alert

            @param form: the FORM
        """

        if "vars" in form:
            form_vars = form.vars
        elif "id" in form:
            form_vars = form
        elif hasattr(form, "vars"):
            form_vars = form.vars
        else:
            form_vars = form

        info_id = form_vars.id
        if not info_id:
            return

        db = current.db
        itable = db.cap_info

        info = db(itable.id == info_id).select(itable.id,
                                               itable.alert_id,
                                               itable.language,
                                               itable.web,
                                               itable.event,
                                               itable.event_type_id,
                                               itable.event_code,
                                               itable.audience,
                                               limitby = (0, 1),
                                               ).first()
        if info:
            alert_id = info.alert_id

            # Details to update in this info-record:
            update = {}

            # Set is_template if alert is template:
            if alert_id and cap_alert_is_template(alert_id):
                update["is_template"] = True

            # If event description is missing, use representation of event_type_id:
            if not info.event:
                update["event"] = itable.event_type_id.represent(info.event_type_id)

            # Event codes may contain invalid JSON => sanitize:
            event_code = info.event_code
            if event_code and ("|{" in event_code or "||" in event_code):
                update["event_code"] = cls.sanitize_json(event_code)

            # Unused, using info_parameter component instead:
            #parameter = info.parameter
            #if parameter and ("|{" in parameter or "||" in parameter):
            #    update["parameter"] = cls.sanitize_json(parameter)

            # Clean up empty audience field
            audience = info.audience
            if not audience or audience == current.messages["NONE"]:
                update["audience"] = None

            # Always US English:
            if info.language == "en":
                update["language"] = "en-US"

            if not info.web:
                # Use the local alert URL for "web"
                atable = current.s3db.cap_alert
                row = db(atable.id == alert_id).select(atable.scope,
                                                       limitby = (0, 1),
                                                       ).first()
                if row and row.scope == "Public":
                    fn = "public"
                else:
                    fn = "alert"
                web = "%s%s" % (current.deployment_settings.get_base_public_url(),
                                URL(c="cap", f=fn, args=[alert_id]),
                                )
                update["web"] = web
            else:
                web = None

            form_vars_get = form_vars.get

            # Defaults for relevance date fields
            form_effective = form_vars_get("effective", current.request.utcnow)
            form_expires = form_vars_get("expires", cap_expirydate())
            form_onset = form_vars_get("onset", form_effective)

            update.update({"effective": form_effective,
                           "expires": form_expires,
                           "onset": form_onset,
                           })

            if update:
                info.update_record(**update)

            # Sync data in all other info-records of the same alert
            idata = {"category"       : form_vars_get("category"),
                     "certainty"      : form_vars_get("certainty"),
                     "effective"      : form_effective,
                     "event_type_id"  : form_vars_get("event_type_id"),
                     "expires"        : form_expires,
                     "onset"          : form_onset,
                     "priority"       : form_vars_get("priority"),
                     "response_type"  : form_vars_get("response_type"),
                     "severity"       : form_vars_get("severity"),
                     "urgency"        : form_vars_get("urgency"),
                     }
            if web:
                idata["web"] = web
            query = (itable.alert_id == alert_id) & \
                    (itable.id != info_id) & \
                    (itable.deleted == False)
            db(query).update(**idata)

    # -------------------------------------------------------------------------
    @staticmethod
    def info_duplicate(item):
        """
            Duplicate detection for info-segments

            @param item: the S3ImportItem
        """

        data = item.data

        alert_id = data.get("alert_id")
        language = data.get("language", "en-US") # assume en-US if not specified

        if alert_id and language:
            table = item.table
            query = (table.alert_id == alert_id) & \
                    (table.language == language)
            duplicate = current.db(query).select(table.id,
                                                 limitby = (0, 1),
                                                 ).first()
            if duplicate:
                item.id = duplicate.id
                item.method = item.METHOD.UPDATE

    # -------------------------------------------------------------------------
    @staticmethod
    def info_parameter_onvalidation(form):
        """
            Form validation for info_parameter
                - currently unused (TODO: document why)

            @param form: the FORM
        """

        form_vars = form.vars
        try:
            name = form_vars.get("name")
            value = form_vars.get("value")
        except AttributeError:
            return

        if not all((name, value)):
            form.errors["name"] = current.T("Name-Value Pair is incomplete.")

    # -------------------------------------------------------------------------
    @staticmethod
    def info_parameter_onaccept(form):
        """
            Onaccept-routine of info parameters
                - inherit alert_id from info segment

            @param form: the FORM
        """

        form_vars = form.vars

        try:
            record_id = form_vars.id
        except AttributeError:
            record_id = None
        if not record_id:
            return

        db = current.db
        itable = db.cap_info
        ptable = db.cap_info_parameter

        query = (ptable.id == record_id)

        # Find the info record ID
        try:
            info_id = form_vars.info_id
        except AttributeError:
            info_id = None
        if not info_id:
            parameter = db(query).select(ptable.info_id, limitby=(0, 1)).first()
            if parameter:
                info_id = parameter.info_id

        if info_id and record_id:
            # Get the alert ID from info record
            info = db(itable.id == info_id).select(itable.alert_id,
                                                   limitby = (0, 1),
                                                   ).first()
            alert_id = info.alert_id

            # Set the alert_id in parameter record
            if alert_id:
                db(query).update(alert_id=alert_id)

    # =============================================================================
    @staticmethod
    def sanitize_json(string):
        """
            Sanitize malformed JSON for key-value fields

            @param string: the JSON string
            @returns: the sanitized JSON string

            TODO unclear why this is needed? => document, or remove?
        """

        if string == "||":
            sanitized = ""
        else:
            sanitized = string.replace(" ", "") \
                              .replace("|", "") \
                              .replace("}{", "},{") \
                              .replace("{u'", "{'") \
                              .replace(":u'", ":'") \
                              .replace(",u'", ",'") \
                              .replace("'", '"')

        return "[%s]" % sanitized

# =============================================================================
class CAPAreaModel(S3Model):

    names = ("cap_area",
             "cap_area_represent",
             "cap_area_location",
             "cap_area_name",
             "cap_area_tag",
             )

    def model(self):

        T = current.T

        db = current.db
        crud_strings = current.response.s3.crud_strings

        define_table = self.define_table
        configure = self.configure

        alert_id = self.cap_alert_id
        info_id = self.cap_info_id

        # ---------------------------------------------------------------------
        # CAP Area segments
        #
        # @ToDo: move the following to developer wiki/blueprint?
        #
        # - Area elements sit inside the Info segment of CAP XML
        # - However, in most cases these would be common across all Info
        #   segments of the same alert, so in the UI we link these
        #   primarily to the Alert but still allow to differentiate by Info
        #
        # - Each <area> can have multiple elements which are one of <polygon>,
        #   <circle>, or <geocode>. <polygon> and <circle> are explicit geometry
        #   elements. <geocode> is a key-value pair in which the key is a standard
        #   geocoding system like SAME, FIPS, ZIP, and the value is a defined
        #   value in that system.
        # - The region described by the <area> is the union of the areas
        #   described by the individual elements, but the CAP spec advises that,
        #   if geocodes are included, the concrete geometry elements should
        #   outline the area specified by the geocodes, as not all recipients
        #   will have access to the meanings of the geocodes. However, since
        #   geocodes are a compact way to describe an area, it may be that they
        #   will be used without accompanying geometry, so we should not count
        #   on having <polygon> or <circle>.
        #
        # - Geometry elements are each represented by a gis_location record,
        #   and linked to the cap_area record via the cap_area_location link
        #   table.
        # - For the moment, <circle> objects are stored with the center in the
        #   gis_location's lat, lon, and radius (in km) as a tag "radius" and
        #   value.
        # - @ToDo: add support for CIRCLESTRING WKT
        #
        # - Geocode elements are currently stored as key value pairs in the
        #   cap_area record.
        # - <area> can also specify a minimum altitude and maximum altitude
        #   ("ceiling"). These are stored in explicit fields for now, but
        #   could be replaced by key value pairs, if it is found that they are
        #   rarely used.
        #
        # - An alternative would be to have cap_area link to a gis_location_group
        #   record. In that case, the geocode tags could be stored in the
        #   gis_location_group's overall gis_location element's tags. The altitude
        #   could be stored in the overall gis_location's elevation, with ceiling
        #   stored in a tag. We could consider adding a maximum elevation field.
        #
        tablename = "cap_area"
        define_table(tablename,
                     alert_id(),
                     # Only used for imports (in UI, area are linked to alert):
                     info_id(readable = False,
                             writable = False,
                             ),
                     # From which template area is the area assigned from:
                     # - used for internationalisation
                     Field("template_area_id", "reference cap_area",
                           ondelete = "SET NULL",
                           readable = False,
                           requires = IS_EMPTY_OR(
                                        IS_ONE_OF(db, "cap_area.id",
                                                  filterby = "is_template",
                                                  filter_opts = (True,),
                                                  )),
                           widget = S3HiddenWidget(),
                           ),
                     Field("is_template", "boolean",
                           default = False,
                           readable = False,
                           writable = False,
                           ),
                     Field("name", length=1024,
                           label = T("Area Description"),
                           requires = [IS_NOT_EMPTY(),
                                       IS_LENGTH(1024),
                                       ],
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The affected area of the alert message"),
                                                             T("A text description of the affected area."),
                                                             ),
                                         ),
                           ),
                     Field("altitude", "integer",
                           # Feet above Sea-level in WGS84 (Specific or Minimum is using a range)
                           label = T("Altitude"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The specific or minimum altitude of the affected area"),
                                                             T("If used with the ceiling element this value is the lower limit of a range. Otherwise, this value specifies a specific altitude. The altitude measure is in feet above mean sea level."),
                                                             ),
                                         ),
                           ),
                     Field("ceiling", "integer",
                           # Feet above Sea-level in WGS84 (Maximum)
                           label = T("Ceiling"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The maximum altitude of the affected area"),
                                                             T("must not be used except in combination with the 'altitude' element. The ceiling measure is in feet above mean sea level."),
                                                             ),
                                         ),
                           ),
                     # Only used for template areas:
                     self.event_type_id(ondelete = "SET NULL",
                                        comment = DIV(_class = "tooltip",
                                                      _title = "%s|%s" % (T("Event Type of this predefined alert area"),
                                                                          T("Event Type relating to this predefined area."),
                                                                          ),
                                                      ),
                                        #script = '''
                                        #    $.filterOptionsS3({
                                        #    'trigger':'event_type_id',
                                        #    'target':'priority',
                                        #    'lookupPrefix': 'cap',
                                        #    'lookupResource': 'warning_priority',
                                        #    'lookupKey': 'event_type_id'
                                        #    })''',
                                        ),
                     # Only relevant for template areas:
                     # - currently unused, re-enable if required
                     #self.cap_warning_priority_id(
                     #   comment = DIV(_class = "tooltip",
                     #                 _title = "%s|%s" % (T("Priority of the Event Type"),
                     #                                     T("Defines the priority of the Event Type for this predefined area."),
                     #                                     ),
                     #                 ),
                     #   ),
                     *s3_meta_fields())

        # Components
        self.add_components(tablename,
                            cap_area_location = {"name": "location",
                                                 "joinby": "area_id",
                                                 },
                            cap_area_tag = {"name": "tag",
                                            "joinby": "area_id",
                                            },
                            cap_area_name = {"name": "name",
                                             "joinby": "area_id",
                                             },
                            )

        # CRUD Form
        crud_form = S3SQLCustomForm("alert_id",
                                    "info_id",
                                    "is_template",
                                    "event_type_id",
                                    #"priority",
                                    "name",
                                    S3SQLInlineComponent("location",
                                                         name = "location",
                                                         multiple = False,
                                                         fields = [("", "location_id")],
                                                         comment = DIV(_class="tooltip",
                                                                       _title="%s|%s" % (T("Geolocation"),
                                                                                         T("The paired values of points defining a polygon that delineates the affected area of the alert message"),
                                                                                         ),
                                                                       ),
                                                         ),
                                    S3SQLInlineComponent("tag",
                                                         name = "tag",
                                                         fields = ["tag",
                                                                   "value",
                                                                   ],
                                                         comment = DIV(_class="tooltip",
                                                                       _title="%s|%s" % (T("The geographic code delineating the affected area"),
                                                                                         T("Any geographically-based code to describe a message target area, in the form. The key is a user-assigned string designating the domain of the code, and the content of value is a string (which may represent a number) denoting the value itself (e.g., name='ZIP' and value='54321'). This should be used in concert with an equivalent description in the more universally understood polygon and circle forms whenever possible."),
                                                                                         ),
                                                                       ),
                                                         ),
                                    "altitude",
                                    "ceiling",
                                    )

        # Table Configuration
        configure(tablename,
                  context = {"location": "location.location_id",
                             },
                  #create_next = URL(f="area", args=["[id]", "location"]),
                  crud_form = crud_form,
                  deduplicate = self.area_duplicate,
                  mark_required = ("event_type_id",),
                  onaccept = self.area_onaccept,
                  onvalidation = self.area_onvalidation,
                  )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            label_create = T("Add Area"),
            title_display = T("Alert Area"),
            title_list = T("Areas"),
            title_update = T("Edit Area"),
            subtitle_list = T("List Areas"),
            label_list_button = T("List Areas"),
            label_delete_button = T("Delete Area"),
            msg_record_created = T("Area added"),
            msg_record_modified = T("Area updated"),
            msg_record_deleted = T("Area deleted"),
            msg_list_empty = T("No areas currently defined for this alert"),
            )

        # Reference Representation
        area_represent = cap_AreaRepresent(show_link=True)

        # Reusable Field
        area_id = S3ReusableField("area_id", "reference %s" % tablename,
                                  label = T("Area"),
                                  ondelete = "CASCADE",
                                  represent = area_represent,
                                  requires = IS_ONE_OF(db, "cap_area.id",
                                                       area_represent,
                                                       ),
                                  )

        # ---------------------------------------------------------------------
        # Area <> Location Link Table
        #
        # @ToDo: Use a widget tailored to entering <polygon> and <circle>:
        #        - we want to be able to enter them by drawing on the map
        #        - we also want to allow selecting existing locations that
        #          have geometry, maybe with some filtering so the list
        #          isn't cluttered with irrelevant locations
        tablename = "cap_area_location"
        define_table(tablename,
                     alert_id(readable = False,
                              writable = False,
                              ),
                     area_id(),
                     self.gis_location_id(
                        widget = S3LocationSelector(points = False,
                                                    polygons = True,
                                                    circles = True,
                                                    show_map = True,
                                                    catalog_layers = True,
                                                    show_address = False,
                                                    show_postcode = False,
                                                    ),
                        ),
                     *s3_meta_fields())

        # Table Configuration
        configure(tablename,
                  deduplicate = S3Duplicate(primary=("area_id", "location_id")),
                  onaccept = self.area_location_onaccept,
                  )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            label_create = T("Add Location"),
            title_display = T("Alert Location"),
            title_list = T("Locations"),
            title_update = T("Edit Location"),
            subtitle_list = T("List Locations"),
            label_list_button = T("List Locations"),
            label_delete_button = T("Delete Location"),
            msg_record_created = T("Location added"),
            msg_record_modified = T("Location updated"),
            msg_record_deleted = T("Location deleted"),
            msg_list_empty = T("No locations currently defined for this alert"),
            )

        # ---------------------------------------------------------------------
        # Local Area Names
        #
        tablename = "cap_area_name"
        define_table(tablename,
                     area_id(empty = False,
                             ondelete = "CASCADE",
                             ),
                     s3_language(empty = False,
                                 select = current.deployment_settings.get_cap_languages(),
                                 ),
                     Field("name_l10n",
                           label = T("Local Name"),
                           ),
                     s3_comments(),
                     *s3_meta_fields())

        # Table Configuration
        configure(tablename,
                  deduplicate = S3Duplicate(primary=("area_id", "language")),
                  )

        # ---------------------------------------------------------------------
        # Area Tags
        # - key-value pairs
        # - used to hold geocodes: key is the geocode system name, and
        #   value is the specific value for this area
        # - could store other values here as well, to avoid dedicated fields
        #   in cap_area for rarely-used items like altitude and ceiling, but
        #   would have to distinguish those from geocodes
        #
        # @ToDo: Provide a mechanism for pre-loading geocodes that are not
        #        tied to individual areas
        # @ToDo: Allow sharing the key-value pairs. Cf. Ruby on Rails tagging
        #        systems such as acts-as-taggable-on, which has a single table
        #        of tags used by all classes. Each tag record has the class
        #        and field that the tag belongs to, as well as the tag string.
        #        We'd want tag and value, but the idea is the same: There would
        #        be a table with tag / value pairs, and individual cap_area,
        #        event_event, org_whatever records would link to records in
        #        the tag table. So we actually would not have duplicate tag
        #        value records as we do now.
        #
        tablename = "cap_area_tag"
        define_table(tablename,
                     alert_id(readable = False,
                              writable = False,
                              ),
                     area_id(),
                     # @ToDo: Allow selecting from a dropdown list of pre-defined
                     #        geocode system names.
                     Field("tag",
                           label = T("Geocode Name"),
                           ),
                     # @ToDo: Once the geocode system is selected, fetch a list
                     #        of current values for that geocode system. Allow
                     #        adding new values, e.g. with combo box menu.
                     Field("value",
                           label = T("Value"),
                           ),
                     s3_comments(),
                     *s3_meta_fields())

        # Table Configuration
        configure(tablename,
                  deduplicate = S3Duplicate(primary=("area_id", "tag", "value")),
                  onaccept = self.area_tag_onaccept,
                  )

        # ---------------------------------------------------------------------
        # Pass names back to global scope (s3.*)
        #
        return {"cap_area_represent": area_represent,
                }

    # -------------------------------------------------------------------------
    @staticmethod
    def defaults():
        """
            Return safe defaults in case the model has been deactivated.
        """

        return {"cap_area_represent": lambda v, row=None: s3_str(v),
                }

    # -------------------------------------------------------------------------
    @staticmethod
    def area_onvalidation(form):
        """
            Validate an area form

            @param form: the Form
        """

        T = current.T

        form_vars = form.vars

        if form_vars.get("ceiling") and not form_vars.get("altitude"):
            form.errors["altitude"] = \
                T("'Altitude' field is mandatory if using 'Ceiling' field.")

        if "event_type_id" in form_vars and form_vars.get("event_type_id") is None:
            form.errors["event_type_id"] = \
                T("'Event Type' field is mandatory for Predefined Area.")

    # -------------------------------------------------------------------------
    @staticmethod
    def area_onaccept(form):
        """
            Onaccept-routine for area segments
                - inherit alert_id from info segment if not set in form

            @param form: the FORM
        """

        form_vars = form.vars

        if form_vars.get("event_type_id"):
            # Predefined Area
            return

        db = current.db

        alert_id = form_vars.get("alert_id")
        if not alert_id:
            info_id = form_vars.get("info_id")
            if info_id:
                # Get the info-segment's alert ID
                itable = db.cap_info
                info = db(itable.id == info_id).select(itable.alert_id,
                                                       limitby = (0, 1),
                                                       ).first()
                alert_id = info.alert_id if info else None

            if alert_id:
                # Set alert_id in cap_area record
                db(db.cap_area.id == form_vars.id).update(alert_id=alert_id)

    # -------------------------------------------------------------------------
    @staticmethod
    def area_duplicate(item):
        """
            Detect an area duplicate

            @param item: the S3ImportItem
        """

        data = item.data
        name = data.get("name")

        if name is not None:
            table = item.table

            event_type_id = data.get("event_type_id")
            if event_type_id is not None:
                # This is a template
                query = (table.name == name) & \
                        (table.event_type_id == event_type_id)
            else:
                alert_id = data.get("alert_id")
                info_id = data.get("info_id")

                query = (table.name == name)
                if alert_id is not None:
                    # Real Alert, not template
                    query &= (table.alert_id == alert_id)
                elif info_id is not None:
                    # CAP XML Import
                    query &= (table.info_id == info_id)
                else:
                    # Nothing we can use
                    return

            duplicate = current.db(query).select(table.id,
                                                 limitby = (0, 1),
                                                 ).first()
            if duplicate:
                item.id = duplicate.id
                item.method = item.METHOD.UPDATE

    # -------------------------------------------------------------------------
    @staticmethod
    def area_location_onaccept(form):
        """
            Onaccept-routine for area-location links
            - inherit alert_id from area-segment (non-template areas only)
            - remove the location link for imported alerts if polygon import
              is not configured (settings.cap.area_default), e.g. SAMBRO/PH
              wants alerts only linked to standard locations by geocode, which
              happens via a tag match (cap_area_tag <=> gis_location_tag)
        """

        form_vars_get = form.vars.get

        area_id = form_vars_get("area_id")
        if not area_id:
            # Coming from assign method => no action
            return

        db = current.db

        # Look up the alert_id
        alert_id = form_vars_get("alert_id")
        if not alert_id:
            atable = db.cap_area
            row = db(atable.id == area_id).select(atable.alert_id,
                                                  limitby = (0, 1),
                                                  ).first()
            if row:
                alert_id = row.alert_id

        if alert_id:
            # Not a template area (template areas have no alert_id)
            area_location_id = form_vars_get("id")

            # Remove the record if the alert is imported and polygon import
            # is not configured (=>a link to a geocode location is created in
            # area_tag_onaccept instead)
            location_default = current.deployment_settings.get_cap_area_default()
            if "polygon" not in location_default:
                table = current.s3db.cap_alert
                row = db(table.id == alert_id).select(table.external,
                                                      limitby = (0, 1),
                                                      ).first()
                if row.external:
                    db(db.cap_area_location.id == area_location_id).delete()
                    return

            # Inherit the alert_id from area
            db(db.cap_area_location.id == area_location_id).update(alert_id = alert_id)

    # -------------------------------------------------------------------------
    @staticmethod
    def area_tag_onaccept(form):
        """
            Onaccept-routine for area tags
            - inherit alert_id from area (non-template areas only)
            - if the tag is a SAME code, create a cap_area_location link
              for the area to the corresponding gis_location
        """

        form_vars = form.vars

        area_id = form_vars.get("area_id")
        if not area_id:
            # Coming from assign method => no action
            return

        db = current.db
        atable = db.cap_area
        arow = db(atable.id == area_id).select(atable.alert_id,
                                               limitby = (0, 1),
                                               ).first()
        alert_id = arow.alert_id

        if alert_id:
            # Not a template area (template areas have no alert_id)

            # Inherit the alert_id
            db(db.cap_area_tag.id == form_vars.id).update(alert_id=alert_id)

            s3db = current.s3db
            settings = current.deployment_settings

            same_code = settings.get_cap_same_code()

            tag = form_vars.get("tag")
            link_location_by_code = False

            if same_code and tag == "SAME":
                # Use this tag to link to an existing gis_location with this
                # code if geocode-import is configured or the alert is generated
                # locally
                if "geocode" in settings.get_cap_area_default():
                    link_location_by_code = True
                else:
                    table = s3db.cap_alert
                    row = db(table.id == alert_id).select(table.external,
                                                          limitby = (0, 1),
                                                          ).first()
                    link_location_by_code = not row.external if row else False

            if link_location_by_code:
                # Look up the gis_location with a matching SAME code
                # - find a matching gis_location_tag where the tag name is the
                #   configured SAME code, and the value matches the value of this
                #   tag
                # - it is possible for there to be two polygons for the same SAME
                #   code since polygon change over time, even if the code remains
                #   the same. Historic polygons are excluded as (gtable.end_date == None)
                ttable = s3db.gis_location_tag
                gtable = s3db.gis_location
                tquery = (ttable.tag == same_code) & \
                         (ttable.value == form_vars.get("value")) & \
                         (ttable.deleted == False) & \
                         (ttable.location_id == gtable.id) & \
                         (gtable.end_date == None) & \
                         (gtable.deleted == False)
                trow = db(tquery).select(ttable.location_id,
                                         limitby = (0, 1),
                                         ).first()
                if trow and trow.location_id:
                    # Match => link area to this location
                    ltable = db.cap_area_location
                    link = {"area_id": area_id,
                            "alert_id": alert_id or None,
                            "location_id": trow.location_id,
                            }
                    link_id = ltable.insert(**link)
                    current.auth.s3_set_record_owner(ltable, link_id)
                    # Currently not required:
                    #link["id"] = link_id
                    #s3db.onaccept(ltable, link)

# =============================================================================
class CAPResourceModel(S3Model):

    names = ("cap_resource",
             )

    def model(self):

        T = current.T

        crud_strings = current.response.s3.crud_strings

        define_table = self.define_table
        configure = self.configure

        alert_id = self.cap_alert_id
        info_id = self.cap_info_id

        # ---------------------------------------------------------------------
        # CAP Resource segments
        #
        # - Resource elements sit inside the Info segment of CAP XML
        # - However, in most cases these would be common across all Info
        #   segments of the same alert, so in the UI we link these
        #   primarily to the Alert but still allow to differentiate by Info
        #
        tablename = "cap_resource"
        define_table(tablename,
                     alert_id(writable = False,
                              ),
                     # Only used for imports (in UI, resource are linked to alert):
                     info_id(readable = False,
                             writable = False,
                             ),
                     Field("is_template", "boolean",
                           default = False,
                           readable = False,
                           writable = False,
                           ),
                     self.super_link("doc_id", "doc_entity"),
                     Field("resource_desc",
                           label = T("Description"),
                           requires = IS_NOT_EMPTY(),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The type and content of the resource file"),
                                                           T("The human-readable text describing the type and content, such as 'map' or 'photo', of the resource file."),
                                                           ),
                                         ),
                           ),
                     # Using image field instead of doc_id because the
                     # CropWidget doesn't work in inline forms
                     Field("image", "upload",
                           label = T("Image"),
                           length = current.MAX_FILENAME_LENGTH,
                           represent = self.doc_image_represent,
                           requires = IS_EMPTY_OR(IS_IMAGE(maxsize = (800, 800),
                                                           error_message = \
                                                            T("Upload an image file(bmp, gif, jpeg or png), max. 800x800 pixels!"))),
                           uploadfolder = os.path.join(current.request.folder,
                                                       "uploads",
                                                       "images",
                                                       ),
                           widget = S3ImageCropWidget((800, 800)),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("Image"),
                                                           T("Attach an image that provides extra information about the event"),
                                                           ),
                                         ),
                           ),
                     Field("mime_type",
                           requires = IS_NOT_EMPTY(),
                           readable = False,
                           writable = False,
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The identifier of the MIME content type and sub-type describing the resource file"),
                                                           T("MIME content type and sub-type as described in [RFC 2046]. (As of this document, the current IANA registered MIME types are listed at http://www.iana.org/assignments/media-types/)"),
                                                           ),
                                         ),
                           ),
                     Field("size", "integer",
                           label = T("Size in Bytes"),
                           readable = False,
                           writable = False,
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The integer indicating the size of the resource file"),
                                                           T("Approximate size of the resource file in bytes."),
                                                           ),
                                         ),
                           ),
                     Field("uri",
                           label = T("Link to any resources"),
                           requires = IS_EMPTY_OR(IS_URL()),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The identifier of the hyperlink for the resource file"),
                                                           T("A full absolute URI, typically a Uniform Resource Locator that can be used to retrieve the resource over the Internet."),
                                                           ),
                                         ),
                           ),
                     #Field("file", "upload"),
                     Field("deref_uri", "text",
                           readable = False,
                           writable = False,
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("Deref URI"),
                                                           T("The base-64 encoded data content of the resource file"),
                                                           ),
                                         ),
                           ),
                     Field("digest",
                           writable = False,
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("The code representing the digital digest ('hash') computed from the resource file"),
                                                           T("Calculated using the Secure Hash Algorithm (SHA-1)."),
                                                           ),
                                         ),
                           ),
                     *s3_meta_fields())

        # CRUD Form
        crud_form = S3SQLCustomForm("alert_id",
                                    "info_id",
                                    "is_template",
                                    "resource_desc",
                                    "uri",
                                    "image",
                                    "mime_type",
                                    "size",
                                    # The CropWidget doesn't work in inline forms
                                    #S3SQLInlineComponent(
                                    #    "image",
                                    #    label = T("Image"),
                                    #    fields = [("", "file")],
                                    #    comment = DIV(_class = "tooltip",
                                    #                  _title = "%s|%s" % (T("Image"),
                                    #                                      T("Attach an image that provides extra information about the event."),
                                    #                                      ),
                                    #                  ),
                                    #    ),
                                    S3SQLInlineComponent(
                                        "document",
                                        label = T("Document"),
                                        fields = [("", "file")],
                                        comment = DIV(_class="tooltip",
                                                      _title="%s|%s" % (T("Document"),
                                                                        T("Attach document that provides extra information about the event."),
                                                                        ),
                                                      ),
                                        ),
                                    )

        # List Fields
        list_fields = ["resource_desc",
                       "uri",
                       "image",
                       "document.file",
                       ]

        # Table Configuration
        configure(tablename,
                  crud_form = crud_form,
                  list_fields = list_fields,
                  onaccept = self.resource_onaccept,
                  onvalidation = self.resource_onvalidation,
                  super_entity = "doc_entity",
                  )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            label_create = T("Add Resource"),
            title_display = T("Alert Resource"),
            title_list = T("Resources"),
            title_update = T("Edit Resource"),
            subtitle_list = T("List Resources"),
            label_list_button = T("List Resources"),
            label_delete_button = T("Delete Resource"),
            msg_record_created = T("Resource added"),
            msg_record_modified = T("Resource updated"),
            msg_record_deleted = T("Resource deleted"),
            msg_list_empty = T("No resources currently defined for this alert"),
            )

        # ---------------------------------------------------------------------
        # Pass names back to global scope (s3.*)
        return {}

    # -------------------------------------------------------------------------
    @staticmethod
    def defaults():
        """
            Return safe defaults in case the model has been deactivated.
        """

        return {}

    # -------------------------------------------------------------------------
    @staticmethod
    def resource_onvalidation(form):
        """
            Resource form validation:
                - post-process S3ImageCropWidget
                - Derived from IS_PROCESSED_IMAGE with extras:
                - Determine MIME type and file size of uploaded image

            @param form: the FORM
        """

        if current.response.s3.bulk:
            # Pointless in imports
            return

        request = current.request

        if request.env.request_method == "GET":
            return

        form_vars = form.vars

        # If there's a newly uploaded file, accept it. It'll be processed in
        # the update form.
        # NOTE: A FieldStorage with data evaluates as False (odd!)
        uploaded_image = form_vars.get("image")
        if uploaded_image not in (b"", None): # Py 3.x it's b"", which is equivalent to "" in Py 2.x
            form_vars.image = uploaded_image
            return

        # Decode the base64-encoded image from the client side image crop
        # process, if that worked
        cropped_image = form_vars.get("imagecrop-data")
        if cropped_image:
            import base64

            metadata, cropped_image = cropped_image.rsplit(",", 1)
            filename, datatype = metadata.split(";")[:2]

            f = Storage()
            f.filename = uuid4().hex + filename
            f.file = stream = BytesIO(base64.b64decode(cropped_image))

            form_vars.image = f

            # Determine file size
            stream.seek(0, os.SEEK_END)
            form_vars.size = stream.tell()
            stream.seek(0)

            # Determine MIME type
            form_vars.mime_type = datatype.split(":")[1]

            return

        record_id = form_vars.id
        if not record_id:
            # Probably a 'create' method
            return

        table = current.s3db.cap_resource
        record = current.db(table.id == record_id).select(table.image,
                                                          limitby = (0, 1)
                                                          ).first()
        uploaded_image = record.image if record else None

        if not uploaded_image:
            # Optional
            return

        # Crop the image, if we've got the crop points
        points = form_vars.get("imagecrop-points")
        if points:
            points = [float(p) for p in points.split(",")]

            path = os.path.join(request.folder,
                                "uploads",
                                "images",
                                uploaded_image,
                                )

            current.s3task.run_async("crop_image",
                                     args = [path] + points + [800],
                                     )
            form_vars.image = uploaded_image

    # -------------------------------------------------------------------------
    @staticmethod
    def resource_onaccept(form):
        """
            Onaccept-routine for resources
                - inherit alert_id from info segment if not set in form

            @param form: the FORM
        """

        form_vars = form.vars

        db = current.db

        alert_id = form_vars.get("alert_id")
        if not alert_id:
            info_id = form_vars.get("info_id")
            if info_id:
                # Get the info-segment's alert ID
                itable = db.cap_info
                info = db(itable.id == info_id).select(itable.alert_id,
                                                       limitby = (0, 1),
                                                       ).first()
                alert_id = info.alert_id if info else None

            if alert_id:
                # Set alert_id in cap_area record
                db(db.cap_resource.id == form_vars.id).update(alert_id = alert_id)

# =============================================================================
class CAPWarningPriorityModel(S3Model):

    names = ("cap_warning_priority",
             "cap_warning_priority_id",
             )

    def model(self):

        T = current.T

        db = current.db
        crud_strings = current.response.s3.crud_strings

        cap_options = get_cap_options()

        # ---------------------------------------------------------------------
        # Warning Priorities
        # - map event-type-specific custom priority classes to combinations
        #   of CAP urgency, severity and certainty
        #
        tablename = "cap_warning_priority"
        self.define_table(tablename,
                          Field("priority_rank", "integer",
                                label = T("Priority Sequence"),
                                length = 2,
                                comment = DIV(_class="tooltip",
                                              _title="%s|%s" % (T("Priority Rank"),
                                                                T("The Priority Rank is basically to give it a ranking 1, 2, ..., n. That way we know 1 is the most important of the chain and n is lowest element. For eg. (1, Signal 1), (2, Signal 2)..., (5, Signal 5) to enumerate the priority for cyclone."),
                                                                ),
                                              ),
                                ),
                          Field("event_code",
                                label = T("Event Code"),
                                comment = DIV(_class="tooltip",
                                              _title="%s|%s" % (T("Event Code"),
                                                                T("Code (key) for the event like for eg. (2001, Typhoon), (2002, Flood)"),
                                                                ),
                                              ),
                                ),
                          Field("name", notnull=True, length=64, unique=True,
                                label = T("Name"),
                                requires = [IS_LENGTH(64),
                                            IS_NOT_ONE_OF(db, "%s.name" % tablename),
                                            IS_MATCH('^[^"\']+$',
                                                     error_message=T('Name cannot be empty and Must not include " or (\')'),
                                                     ),
                                            ],
                                comment = DIV(_class="tooltip",
                                              _title="%s|%s" % (T("Name"),
                                                                T("The actual name for the warning priority, for eg. Typhoons in Philippines have five priority names (PSWS# 1, PSWS# 2, PSWS# 3, PSWS# 4 and PSWS# 5)"),
                                                                ),
                                              ),
                                ),
                          self.event_type_id(empty=False,
                                             ondelete = "SET NULL",
                                             label = T("Event Type"),
                                             comment = DIV(_class="tooltip",
                                                           _title="%s|%s" % (T("Event Type"),
                                                                             T("The Event to which this priority is targeted for."),
                                                                             ),
                                                           ),
                                             ),
                          Field("urgency",
                                label = T("Urgency"),
                                requires = IS_IN_SET(cap_options["urgency"]),
                                comment = DIV(_class="tooltip",
                                              _title="%s|%s" % (T("Urgency"),
                                                                T("Denotes the urgency of the subject event of the alert message"),
                                                                ),
                                              ),
                                ),
                          Field("severity",
                                label = T("Severity"),
                                requires = IS_IN_SET(cap_options["severity"]),
                                comment = DIV(_class="tooltip",
                                              _title="%s|%s" % (T("Severity"),
                                                                T("Denotes the severity of the subject event of the alert message"),
                                                                ),
                                              ),
                                ),
                          Field("certainty",
                                label = T("Certainty"),
                                requires = IS_IN_SET(cap_options["certainty"]),
                                comment = DIV(_class="tooltip",
                                              _title="%s|%s" % (T("Certainty"),
                                                                T("Denotes the certainty of the subject event of the alert message"),
                                                                ),
                                              ),
                                ),
                          Field("color_code",
                                label = T("Color Code"),
                                represent = self.color_code_represent,
                                widget = S3ColorPickerWidget(options = {"showPaletteOnly": False,
                                                                        },
                                                             ),
                                comment = DIV(_class="tooltip",
                                              _title="%s|%s" % (T("The color code for this priority"),
                                                                T("Pick from the color widget the color that is associated to this priority of the event. The color code is in hex format"),
                                                                ),
                                              ),
                                ),
                          # Field to record the last checked time for the table
                          # - used to sent notifications to subscribers about available options
                          s3_datetime("last_checked",
                                      readable = False,
                                      writable = False,
                                      ),
                          *s3_meta_fields())

        # List Fields
        list_fields = ["event_type_id",
                       (T("Color"), "color_code"),
                       "name",
                       (T("Rank"), "priority_rank"),
                       ]

        # Table Configuration
        self.configure(tablename,
                       onaccept = self.warning_priority_onaccept,
                       # Not needed since unique=True
                       #deduplicate = S3Duplicate(primary=("event_type_id", "name")),
                       list_fields = list_fields,
                       #onvalidation = self.warning_priority_onvalidation,
                       orderby = "cap_warning_priority.event_type_id,cap_warning_priority.priority_rank desc",
                       )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            label_create = T("Create Warning Classification"),
            title_display = T("Warning Classification Details"),
            title_list = T("Warning Classifications"),
            title_update = T("Edit Warning Classification"),
            title_upload = T("Import Warning Classifications"),
            label_list_button = T("List Warning Classifications"),
            label_delete_button = T("Delete Warning Classification"),
            msg_record_created = T("Warning Classification added"),
            msg_record_modified = T("Warning Classification updated"),
            msg_record_deleted = T("Warning Classification removed"),
            msg_list_empty = T("No Warning Classifications currently registered"),
            )

        # Reusable Field
        represent = S3Represent(lookup=tablename, translate=True)
        priority_id = S3ReusableField("priority", "reference %s" % tablename,
                                      label = T("Priority"),
                                      represent = represent,
                                      requires = IS_EMPTY_OR(
                                                    IS_ONE_OF(db, "%s.id" % tablename,
                                                              represent
                                                              )),
                                      )

        # ---------------------------------------------------------------------
        # Pass names back to global scope (s3.*)
        return {"cap_warning_priority_id": priority_id,
                }

    # -------------------------------------------------------------------------
    @staticmethod
    def defaults():
        """
            Return safe defaults in case the model has been deactivated.
        """


        return {"cap_warning_priority_id": S3ReusableField.dummy("priority"),
                }

    # -------------------------------------------------------------------------
    @staticmethod
    def warning_priority_onvalidation(form):
        """
            Form validation for warning priorities:
                - check for duplicates
                - currently unused (TODO: document why)

            @param form: the FORM
        """

        form_vars = form.vars
        table = current.s3db.cap_warning_priority
        query = (table.event_type_id == form_vars.event_type_id) & \
                (table.urgency == form_vars.urgency) & \
                (table.severity == form_vars.severity) & \
                (table.certainty == form_vars.certainty) & \
                (table.deleted == False)
        row = current.db(query).select(table.id, limitby=(0, 1)).first()
        if row:
            form.errors["event_type_id"] = current.T("This combination of the 'Event Type', 'Urgency', 'Certainty' and 'Severity' is already available in database.")

    # -------------------------------------------------------------------------
    @staticmethod
    def warning_priority_onaccept(form):
        """
            Onaccept-routine for warning priorities
                - add or update the fill rule (color) to all known CAP map styles
        """

        form_vars = form.vars

        name = form_vars.name
        color_code = form_vars.color_code

        if name and color_code:

            db = current.db
            s3db = current.s3db

            # The style ryle for this priority
            pstyle = {"prop": "priority",
                      "cat": name,
                      "fill": color_code,
                      "fillOpacity": 0.4,
                      }

            # Get map styles for all layers with controller=="cap"
            stable = s3db.gis_style
            ftable = s3db.gis_layer_feature
            query = (ftable.controller == "cap") & \
                    (ftable.layer_id == stable.layer_id)
            rows = db(query).select(stable.id, stable.style)

            for row in rows:

                found = False

                style = row.style # Usually a list (JSON array), but could be empty

                if type(style) is list:
                    # If there is already a style rule for this priority,
                    # update it, otherwise append it to the list
                    for rule in style:
                        if rule.get("prop") == "priority" and \
                           rule.get("cat") == name:
                            rule.update(pstyle)
                            found = True
                    if not found:
                        style.append(pstyle)
                else:
                    # No rules in map style yet => start a new list
                    style = [pstyle]

                # Update the map style
                row.update_record(style=style)

    # -------------------------------------------------------------------------
    @staticmethod
    def color_code_represent(color_code):
        """
            Represent a hex color code as a colored DIV

            @param color_code: the color code

            @returns: the representation XML
        """

        if not color_code:
            output = current.messages["NONE"]
        else:
            style = "width:%(size)s;height:%(size)s;background-color:#%(color)s;"
            output = DIV(_style = style % {"size": "2em", "color": color_code})

        return output

# =============================================================================
class CAPHistoryModel(S3Model):
    """ TODO docstring (what is this used for?) """

    names = ("cap_alert_history",
             "cap_info_history",
             "cap_info_parameter_history",
             "cap_resource_history",
             "cap_area_history",
             "cap_area_location_history",
             "cap_area_tag_history",
             )

    def model(self):

        T = current.T

        db = current.db
        settings = current.deployment_settings
        crud_strings = current.response.s3.crud_strings

        define_table = self.define_table
        configure = self.configure
        add_components = self.add_components

        cap_options = get_cap_options()

        incident_types = cap_options["incident_types"]
        status_opts = cap_options["alert_status"]
        msg_types = cap_options["msg_types"]
        scopes = cap_options["scopes"]

        categories = cap_options["categories"]
        response_types = cap_options["response_types"]
        urgency_opts = cap_options["urgency"]
        severity_opts = cap_options["severity"]
        certainty_opts = cap_options["certainty"]

        # ---------------------------------------------------------------------
        # Alert History Table
        # - stores copies of approved alerts without any external references
        #
        tablename = "cap_alert_history"
        define_table(tablename,
                     Field("event_type",
                           requires = IS_NOT_EMPTY(),
                           ),
                     Field("identifier", unique=True, length=255,
                           label = T("Identifier"),
                           requires = [IS_LENGTH(255),
                                       IS_MATCH(OIDPATTERN,
                                                error_message = T("Cannot be empty and Must not include spaces, commas, or restricted characters (< and &)."),
                                                ),
                                       ],
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("A unique identifier of the alert message"),
                                                             T("A number or string uniquely identifying this message, assigned by the sender. Must not include spaces, commas or restricted characters (< and &)."),
                                                             ),
                                         ),
                           ),
                     Field("incidents", "list:string",
                           label = T("Incidents"),
                           represent = S3Represent(options = incident_types,
                                                   multiple = True,
                                                   ),
                           requires = IS_EMPTY_OR(
                                        IS_IN_SET(incident_types,
                                                  multiple = True,
                                                  sort = True,
                                                  )),
                           widget = S3MultiSelectWidget(selectedList=10),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("A list of incident(s) referenced by the alert message"),
                                                             T("Used to collate multiple messages referring to different aspects of the same incident. If multiple incident identifiers are referenced, they SHALL be separated by whitespace.  Incident names including whitespace SHALL be surrounded by double-quotes."),
                                                             ),
                                         ),
                           ),
                     Field("sender",
                           label = T("Sender"),
                           requires = IS_MATCH(OIDPATTERN,
                                               error_message = T("Cannot be empty and Must not include spaces, commas, or restricted characters (< and &)."),
                                               ),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The identifier of the sender of the alert message"),
                                                             T("This is guaranteed by assigner to be unique globally; e.g., may be based on an Internet domain name. Must not include spaces, commas or restricted characters (< and &)."),
                                                             ),
                                         ),
                           ),
                     s3_datetime("sent"),
                     Field("status",
                           label = T("Status"),
                           represent = S3Represent(options=status_opts),
                           requires = IS_IN_SET(status_opts),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Denotes the appropriate handling of the alert message"),
                                                             T("See options."),
                                                             ),
                                         ),
                           ),
                     Field("msg_type",
                           label = T("Message Type"),
                           represent = S3Represent(options=msg_types),
                           requires = IS_EMPTY_OR(IS_IN_SET(msg_types)),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The nature of the alert message"),
                                                             T("See options."),
                                                             ),
                                         ),
                           ),
                     Field("source",
                           label = T("Source"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The text identifying the source of the alert message"),
                                                             T("The particular source of this alert; e.g., an operator or a specific device."),
                                                             ),
                                         ),
                           ),
                     Field("scope",
                           label = T("Scope"),
                           represent = S3Represent(options=scopes),
                           requires = IS_EMPTY_OR(IS_IN_SET(scopes)),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Denotes the intended distribution of the alert message"),
                                                             T("Who is this alert for?"),
                                                             ),
                                         ),
                           ),
                     Field("restriction", "text",
                           label = T("Restriction"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The text describing the rule for limiting distribution of the restricted alert message"),
                                                             T("Used when scope is 'Restricted'."),
                                                             ),
                                         ),
                           ),
                     # TODO introduce a separate "recipients"-field (list:reference pr_pentity)
                     #      and translate it onaccept into addresses
                     Field("addresses", "list:string",
                           label = T("Recipients"),
                           requires = IS_EMPTY_OR(
                                        IS_IN_SET(get_cap_alert_addresses_opts(),
                                                  multiple = True,
                                                  sort = True,
                                                  )
                                        ),
                           represent = S3Represent(lookup = "pr_group",
                                                   fields = ["name"],
                                                   multiple = True,
                                                   ),
                           widget = S3MultiSelectWidget(),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The group listing of intended recipients of the alert message"),
                                                             T("Required when scope is 'Private', optional when scope is 'Public' or 'Restricted'. Each recipient shall be identified by an identifier or an address."),
                                                             ),
                                         ),
                           ),
                     Field("codes", "list:string",
                           label = T("Codes"),
                           represent = list_string_represent,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Codes for special handling of the message"),
                                                             T("Any user-defined flags or special codes used to flag the alert message for special handling."),
                                                             ),
                                         ),
                           ),
                     Field("note", "text",
                           label = T("Note"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The text describing the purpose or significance of the alert message"),
                                                             T("The message note is primarily intended for use with status 'Exercise' and message type 'Error'"),
                                                             ),
                                         ),
                           ),
                     Field("reference", "text",
                           label = T("Reference"),
                           readable = False,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The group listing identifying earlier message(s) referenced by the alert message"),
                                                             T("The extended message identifier(s) (in the form sender,identifier,sent) of an earlier CAP message or messages referenced by this one."),
                                                             ),
                                         ),
                           ),
                     s3_datetime("approved_on",
                                 readable = False,
                                 ),
                     *s3_meta_fields())

        # Components
        add_components(tablename,
                       cap_area_history = "alert_history_id",
                       cap_area_location_history = {"name": "location_history",
                                                    "joinby": "alert_history_id",
                                                    },
                       cap_area_tag_history = {"name": "tag_history",
                                               "joinby": "alert_history_id",
                                               },
                       cap_info_history = "alert_history_id",
                       cap_info_parameter_history = "alert_history_id",
                       cap_resource_history = "alert_history_id",
                       )

        # List Fields
        list_fields = [(T("Event Type"), "info_history.event"),
                       "msg_type",
                       (T("Sent"), "sent"),
                       "info_history.headline",
                       "info_history.sender_name",
                       "created_by",
                       "approved_by",
                       (T("Approved On"), "approved_on"),
                       ]

        # Filter Widgets
        filter_widgets = [
            S3TextFilter(["identifier",
                          "sender",
                          "incidents",
                          "cap_info_history.headline",
                          "cap_info_history.event",
                          ],
                         label = T("Search"),
                         comment = T("Search for an Alert by sender, incident, headline or event."),
                         ),
            S3OptionsFilter("info_history.category",
                            label = T("Category"),
                            options = categories,
                            hidden = True,
                            ),
            S3OptionsFilter("info_history.event",
                            hidden = True,
                            ),
            S3OptionsFilter("scope",
                            hidden = True,
                            ),
            S3OptionsFilter("info_history.priority",
                            hidden = True,
                            ),
            S3OptionsFilter("info_history.language",
                            label = T("Language"),
                            hidden = True,
                            ),
            ]

        # Table Configuration
        configure(tablename,
                  deletable = False,
                  editable = False,
                  filter_widgets = filter_widgets,
                  insertable = False,
                  list_fields = list_fields,
                  orderby = "cap_info_history.expires desc",
                  )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            title_display = T("Alert History Details"),
            title_list = T("Alerts History"),
            label_list_button = T("List Alerts History"),
            msg_list_empty = T("No alerts to show"),
            )

        # Reference Representation
        alert_history_represent = S3Represent(lookup = tablename,
                                              fields = ["msg_type",
                                                        "sent",
                                                        "sender",
                                                        ],
                                              field_sep = " - ",
                                              )

        # Reusable Field
        alert_history_id = S3ReusableField("alert_history_id", "reference %s" % tablename,
                                comment = T("The alert message containing this information"),
                                label = T("Alert History"),
                                ondelete = "CASCADE",
                                represent = alert_history_represent,
                                requires = IS_EMPTY_OR(
                                            IS_ONE_OF(db, "cap_alert_history.id",
                                                      alert_history_represent,
                                                      )),
                                )

        # ---------------------------------------------------------------------
        # CAP Info History Table
        #

        # TODO: avoid changing settings in model, pass directly to
        #       validator via s3_language
        settings.L10n.extra_codes = [("en-US", "English"),
                                     ]

        tablename = "cap_info_history"
        define_table(tablename,
                     alert_history_id(readable = False,
                                      writable = False,
                                      ),
                     s3_language(empty = False,
                                 comment = DIV(_class = "tooltip",
                                               _title = "%s|%s" % (T("Denotes the language of the information"),
                                                                   T("Code Values: Natural language identifier per [RFC 3066]. If not present, an implicit default value of 'en-US' will be assumed. Edit settings.cap.languages in 000_config.py to add more languages. See <a href=\"%s\">here</a> for a full list.") % "http://www.i18nguy.com/unicode/language-identifiers.html",
                                                                   ),
                                               ),
                                 ),
                     Field("category", "list:string",
                           label = T("Category"),
                           represent = S3Represent(options = categories,
                                                   multiple = True,
                                                   ),
                           requires = IS_IN_SET(categories,
                                                multiple = True,
                                                ),
                           widget = S3MultiSelectWidget(selectedList = 10),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Denotes the category of the subject event of the alert message"),
                                                             T("You may select multiple categories by holding down control and then selecting the items."),
                                                             ),
                                         ),
                           ),
                     Field("event",
                           label = T("Event"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The text denoting the type of the subject event of the alert message"),
                                                             T("If not specified, will the same as the Event Type."),
                                                             ),
                                         ),
                           ),
                     Field("response_type", "list:string",
                           label = T("Response Type"),
                           represent = S3Represent(options = response_types,
                                                   multiple = True,
                                                   ),
                           requires = IS_IN_SET(response_types,
                                                multiple = True,
                                                ),
                           widget = S3MultiSelectWidget(selectedList = 10),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Denotes the type of action recommended for the target audience"),
                                                             T("Multiple response types can be selected by holding down control and then selecting the items"),
                                                             ),
                                         ),
                           ),
                     Field("priority",
                           label = T("Priority"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Priority of the alert message"),
                                                             T("Defines the priority of the alert message. Selection of the priority automatically sets the value for 'Urgency', 'Severity' and 'Certainty'"),
                                                             ),
                                         ),
                           ),
                     Field("urgency",
                           label = T("Urgency"),
                           represent = S3Represent(options=urgency_opts),
                           requires = IS_IN_SET(urgency_opts),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Urgency"),
                                                             T("Denotes the urgency of the subject event of the alert message"),
                                                             ),
                                         ),
                           ),
                     Field("severity",
                           label = T("Severity"),
                           represent = S3Represent(options=severity_opts),
                           requires = IS_IN_SET(severity_opts),
                           comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("Severity"),
                                                           T("Denotes the severity of the subject event of the alert message"),
                                                           ),
                                         ),
                           ),
                     Field("certainty",
                           label = T("Certainty"),
                           represent = S3Represent(options=certainty_opts),
                           requires = IS_IN_SET(certainty_opts),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Certainty"),
                                                             T("Denotes the certainty of the subject event of the alert message"),
                                                             ),
                                         ),
                           ),
                     Field("audience", "text",
                           label = T("Audience"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Audience"),
                                                             T("The intended audience of the alert message"),
                                                             ),
                                         ),
                           ),
                     Field("event_code", "text",
                           label = T("Event Code"),
                           represent = S3KeyValueWidget.represent,
                           widget = S3KeyValueWidget(),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("A system-specific code identifying the event type of the alert message"),
                                                             T("Any system-specific code for events, in the form of key-value pairs. (e.g., SAME, FIPS, ZIP)."),
                                                             ),
                                         ),
                           ),
                     s3_datetime("effective",
                                 label = T("Effective"),
                                 comment = DIV(_class = "tooltip",
                                               _title = "%s|%s" % (T("The effective time of the information of the alert message"),
                                                                   T("If not specified, the effective time shall be assumed to be the same the time the alert was sent."),
                                                                   ),
                                               ),
                                 ),
                     s3_datetime("onset",
                                 label = T("Onset"),
                                 comment = DIV(_class = "tooltip",
                                               _title = "%s|%s" % (T("Onset"),
                                                                   T("The expected time of the beginning of the subject event of the alert message"),
                                                                   ),
                                               ),
                                 ),
                     s3_datetime("expires",
                                 label = T("Expires at"),
                                 #past = 0,
                                 comment = DIV(_class = "tooltip",
                                               _title = "%s|%s" % (T("The expiry time of the information of the alert message"),
                                                                   T("If this item is not provided, each recipient is free to enforce its own policy as to when the message is no longer in effect."),
                                                                   ),
                                               ),
                                 ),
                     Field("sender_name",
                           label = T("Sender's name"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The text naming the originator of the alert message"),
                                                             T("The human-readable name of the agency or authority issuing this alert."),
                                                             ),
                                         ),
                           ),
                     Field("headline",
                           label = T("Headline"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The text headline of the alert message"),
                                                             T("A brief human-readable headline.  Note that some displays (for example, short messaging service devices) may only present this headline; it should be made as direct and actionable as possible while remaining short.  160 characters may be a useful target limit for headline length."),
                                                             ),
                                         ),
                           ),
                     Field("description", "text",
                           label = T("Description"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The subject event of the alert message"),
                                                             T("An extended human readable description of the hazard or event that occasioned this message."),
                                                             ),
                                         ),
                           ),
                     Field("instruction", "text",
                           label = T("Instruction"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The recommended action to be taken by recipients of the alert message"),
                                                             T("An extended human readable instruction to targeted recipients.  If different instructions are intended for different recipients, they should be represented by use of multiple information blocks. You can use a different information block also to specify this information in a different language."),
                                                             ),
                                         ),
                           ),
                     Field("contact", "text",
                           label = T("Contact information"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Contact"),
                                                             T("The contact for follow-up and confirmation of the alert message"),
                                                             ),
                                         ),
                           ),
                     Field("web",
                           label = T("URL"),
                           requires = IS_EMPTY_OR(IS_URL()),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("A URL associating additional information with the alert message"),
                                                             T("A full, absolute URI for an HTML page or other text resource with additional or reference information regarding this alert."),
                                                             ),
                                         ),
                           ),
                     #Field("parameter", "text",
                     #      label = T("Parameters"),
                     #      represent = S3KeyValueWidget.represent,
                     #      widget = S3KeyValueWidget(key_label = T("Name")),
                     #      comment = DIV(_class = "tooltip",
                     #                    _title = "%s|%s" % (T("A system-specific additional parameter associated with the alert message"),
                     #                                        T("Any system-specific datum, in the form of key-value pairs."),
                     #                                        ),
                     #                    ),
                     #      ),
                     *s3_meta_fields())

        # Components
        add_components(tablename,
                       cap_info_parameter_history = "info_history_id",
                       )

        # CRUD Form
        crud_form = S3SQLCustomForm("alert_history_id",
                                    "language",
                                    "category",
                                    "event",
                                    "response_type",
                                    "priority",
                                    "urgency",
                                    "severity",
                                    "certainty",
                                    "audience",
                                    "event_code",
                                    "effective",
                                    "onset",
                                    "expires",
                                    "sender_name",
                                    "headline",
                                    "description",
                                    "instruction",
                                    "contact",
                                    "web",
                                    S3SQLInlineComponent(
                                        "info_parameter_history",
                                        name = "info_parameter_history",
                                        label = T("Parameter"),
                                        fields = ["name",
                                                  "value",
                                                  "mobile",
                                                  ],
                                        comment = DIV(_class = "tooltip",
                                                      _title = "%s|%s" % (T("A system-specific additional parameter associated with the alert message"),
                                                                          T("Any system-specific datum, in the form of key-value pairs."),
                                                                          ),
                                                      ),
                                        ),
                                    )

        # List Fields
        list_fields = ["language",
                       "category",
                       (T("Event Type"), "event"),
                       "response_type",
                       "priority",
                       "urgency",
                       "severity",
                       "certainty",
                       "sender_name",
                       ]

        # Reference Representation
        info_history_represent = S3Represent(lookup = tablename,
                                             fields = ["language", "headline"],
                                             field_sep = " - ",
                                             )

        # Reusable Field
        info_history_id = S3ReusableField("info_history_id", "reference %s" % tablename,
                                          label = T("Information History Segment"),
                                          ondelete = "CASCADE",
                                          represent = info_history_represent,
                                          requires = IS_EMPTY_OR(
                                                        IS_ONE_OF(db, "cap_info_history.id",
                                                                  info_history_represent,
                                                                  )),
                                          )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            title_display = T("Alert information History"),
            title_list = T("Information History entries"),
            subtitle_list = T("Listing of alert information History items"),
            label_list_button = T("List information History entries"),
            msg_list_empty = T("No alert information to show"),
            )

        # Table Configuration
        configure(tablename,
                  crud_form = crud_form,
                  deletable = False,
                  editable = False,
                  insertable = False,
                  list_fields = list_fields,
                  )

        # ---------------------------------------------------------------------
        # CAP Info Parameters History
        #
        tablename = "cap_info_parameter_history"
        define_table(tablename,
                     alert_history_id(),
                     info_history_id(),
                     Field("name",
                           label = T("Name"),
                           ),
                     Field("value",
                           label = T("Value"),
                           ),
                     Field("mobile", "boolean",
                           default = False,
                           label = T("Mobile"),
                           represent = s3_yes_no_represent,
                           ),
                     *s3_meta_fields())

        # Table Configuration
        configure(tablename,
                  deletable = False,
                  editable = False,
                  insertable = False,
                  )

        # ---------------------------------------------------------------------
        # CAP Area segments history table
        #
        tablename = "cap_area_history"
        define_table(tablename,
                     alert_history_id(readable = False,
                                      writable = False,
                                      ),
                     Field("name",
                           label = T("Area Description"),
                           required = True,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The affected area of the alert message"),
                                                             T("A text description of the affected area."),
                                                             ),
                                         ),
                           ),
                     Field("altitude", "integer",
                           label = T("Altitude"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The specific or minimum altitude of the affected area"),
                                                             T("If used with the ceiling element this value is the lower limit of a range. Otherwise, this value specifies a specific altitude. The altitude measure is in feet above mean sea level."),
                                                             ),
                                         ),
                           ),
                     Field("ceiling", "integer",
                           label = T("Ceiling"),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The maximum altitude of the affected area"),
                                                             T("must not be used except in combination with the 'altitude' element. The ceiling measure is in feet above mean sea level."),
                                                             ),
                                         ),
                           ),
                     *s3_meta_fields())

        # Components
        add_components(tablename,
                       cap_area_location_history = {"name": "location_history",
                                                    "joinby": "area_history_id",
                                                    },
                       cap_area_tag_history = {"name": "tag_history",
                                               "joinby": "area_history_id",
                                               },
                       )

        # CRUD Form
        crud_form = S3SQLCustomForm("alert_history_id",
                                    "name",
                                    S3SQLInlineComponent(
                                        "location_history",
                                        name = "location",
                                        multiple = False,
                                        fields = [("", "location")],
                                        comment = DIV(_class = "tooltip",
                                                      _title = "%s|%s" % (T("Geolocation"),
                                                                          T("The paired values of points defining a polygon that delineates the affected area of the alert message"),
                                                                          ),
                                                      ),
                                        ),
                                    S3SQLInlineComponent(
                                        "tag_history",
                                        name = "tag",
                                        fields = ["tag",
                                                  "value",
                                                  ],
                                        comment = DIV(_class = "tooltip",
                                                      _title = "%s|%s" % (T("The geographic code delineating the affected area"),
                                                                          T("Any geographically-based code to describe a message target area, in the form. The key is a user-assigned string designating the domain of the code, and the content of value is a string (which may represent a number) denoting the value itself (e.g., name='ZIP' and value='54321'). This should be used in concert with an equivalent description in the more universally understood polygon and circle forms whenever possible."),
                                                                          ),
                                                      ),
                                        ),
                                    "altitude",
                                    "ceiling",
                                    )

        # List Fields
        list_fields = ["name",
                       "altitude",
                       "ceiling",
                       ]

        # Table Configuration
        configure(tablename,
                  crud_form = crud_form,
                  deletable = False,
                  editable = False,
                  insertable = False,
                  list_fields = list_fields,
                  )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            title_display = T("Alert Area History"),
            title_list = T("Areas History"),
            subtitle_list = T("List Areas History"),
            label_list_button = T("List Areas History"),
            msg_list_empty = T("No areas currently defined for this alert"),
            )

        # Reusable Field
        represent = cap_AreaRepresent(show_link=True)
        area_history_id = S3ReusableField("area_history_id", "reference %s" % tablename,
                                          label = T("Area"),
                                          ondelete = "CASCADE",
                                          represent = represent,
                                          requires = IS_ONE_OF(db, "cap_area_history.id",
                                                               represent,
                                                               ),
                                          )

        # ---------------------------------------------------------------------
        # CAP Area Locations history table
        #
        tablename = "cap_area_location_history"
        define_table(tablename,
                     alert_history_id(readable = False,
                                      writable = False,
                                      ),
                     area_history_id(),
                     Field("location_wkt", "text"),
                     *s3_meta_fields())

        # Table Configuration
        configure(tablename,
                  deletable = False,
                  editable = False,
                  insertable = False,
                  )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            title_display = T("Alert Location History"),
            title_list = T("Locations History"),
            subtitle_list = T("List Locations History"),
            label_list_button = T("List Locations History"),
            msg_list_empty = T("No locations currently defined for this alert"),
            )

        # ---------------------------------------------------------------------
        # CAP Area Tags history table
        #
        tablename = "cap_area_tag_history"
        define_table(tablename,
                     alert_history_id(readable = False,
                                      writable = False,
                                      ),
                     area_history_id(),
                     Field("tag",
                           label = T("Geocode Name"),
                           ),
                     Field("value",
                           label = T("Value"),
                           ),
                     s3_comments(),
                     *s3_meta_fields())

        # Table Configuration
        configure(tablename,
                  deletable = False,
                  editable = False,
                  insertable = False,
                  )

        # ---------------------------------------------------------------------
        # CAP Resource History segments
        #
        tablename = "cap_resource_history"
        define_table(tablename,
                     alert_history_id(readable = False,
                                      writable = False,
                                      ),
                     Field("resource_desc",
                           requires = IS_NOT_EMPTY(),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The type and content of the resource file"),
                                                             T("The human-readable text describing the type and content, such as 'map' or 'photo', of the resource file."),
                                                             ),
                                         ),
                           ),
                     Field("image", "upload",
                           label = T("Image"),
                           length = current.MAX_FILENAME_LENGTH,
                           represent = self.doc_image_represent,
                           requires = IS_EMPTY_OR(
                                        IS_IMAGE(maxsize = (800, 800),
                                                 error_message = T("Upload an image file(bmp, gif, jpeg or png), max. 800x800 pixels!"),
                                                 )),
                           uploadfolder = os.path.join(current.request.folder,
                                                       "uploads",
                                                       "images",
                                                       ),
                           widget = S3ImageCropWidget((800, 800)),
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Image"),
                                                             T("Attach an image that provides extra information about the event"),
                                                             ),
                                         ),
                           ),
                     Field("mime_type",
                           requires = IS_NOT_EMPTY(),
                           readable = False,
                           writable = False,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The identifier of the MIME content type and sub-type describing the resource file"),
                                                             T("MIME content type and sub-type as described in [RFC 2046]. (As of this document, the current IANA registered MIME types are listed at http://www.iana.org/assignments/media-types/)"),
                                                             ),
                                         ),
                           ),
                     Field("size", "integer",
                           label = T("Size in Bytes"),
                           readable = False,
                           writable = False,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The integer indicating the size of the resource file"),
                                                             T("Approximate size of the resource file in bytes."),
                                                             ),
                                         ),
                           ),
                     Field("uri",
                           label = T("Link to any resources"),
                           requires = IS_EMPTY_OR(IS_URL()),
                           readable = False,
                           writable = False,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The identifier of the hyperlink for the resource file"),
                                                             T("A full absolute URI, typically a Uniform Resource Locator that can be used to retrieve the resource over the Internet."),
                                                             ),
                                         ),
                           ),
                     Field("deref_uri", "text",
                           readable = False,
                           writable = False,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("Deref URI"),
                                                             T("The base-64 encoded data content of the resource file"),
                                                             ),
                                         ),
                           ),
                     Field("digest",
                           writable = False,
                           comment = DIV(_class = "tooltip",
                                         _title = "%s|%s" % (T("The code representing the digital digest ('hash') computed from the resource file"),
                                                             T("Calculated using the Secure Hash Algorithm (SHA-1)."),
                                                             ),
                                         ),
                           ),
                     *s3_meta_fields())

        # CRUD Form
        crud_form = S3SQLCustomForm("alert_history_id",
                                    "resource_desc",
                                    "uri",
                                    "image",
                                    "mime_type",
                                    "size",
                                    )

        # List Fields
        list_fields = ["resource_desc",
                       "image",
                       ]

        # Table Configuration
        configure(tablename,
                  crud_form = crud_form,
                  deletable = False,
                  editable = False,
                  insertable = False,
                  list_fields = list_fields,
                  )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            title_display = T("Alert Resource History"),
            title_list = T("Resources History"),
            subtitle_list = T("List Resources History"),
            label_list_button = T("List Resources History"),
            msg_list_empty = T("No resources currently defined for this alert"),
            )

        # ---------------------------------------------------------------------
        # Pass names back to global scope (s3.*)
        return {}

    # -------------------------------------------------------------------------
    @staticmethod
    def defaults():
        """
            Return safe defaults in case the model has been deactivated.
        """

        return {}

# =============================================================================
class CAPAlertingAuthorityModel(S3Model):
    """
        Model for known Alerting Authorities
            - see http://alerting.worldweather.org
    """

    names = ("cap_alerting_authority",
             "cap_authority_feed_url",
             "cap_authority_forecast_url"
             )

    def model(self):

        T = current.T

        db = current.db
        crud_strings = current.response.s3.crud_strings

        messages = current.messages

        define_table = self.define_table

        # ---------------------------------------------------------------------
        # Alerting authority
        #
        tablename = "cap_alerting_authority"
        define_table(tablename,
                     Field("oid", unique=True, length=255,
                           label = T("CAP OID"),
                           requires = [IS_LENGTH(255),
                                       IS_MATCH(OIDPATTERN,
                                                error_message=T("Cannot be empty and Must not include spaces, commas, or restricted characters (< and &)."),
                                                ),
                                       ],
                           ),
                     self.org_organisation_id(
                        empty = False,
                        widget = None, # Use simple drop-down
                        comment = S3PopupLink(c = "org",
                                              f = "organisation",
                                              label = T("Create Organization"),
                                              title = messages.ORGANISATION,
                                              ),
                        ),
                     Field("country", length=2,
                           label = T("Country"),
                           represent = self.gis_country_code_represent,
                           requires = IS_EMPTY_OR(
                                        IS_IN_SET_LAZY(lambda: current.gis.get_countries(key_type="code"),
                                                       zero = messages.SELECT_LOCATION,
                                                       )),
                           ),
                     Field("authorisation", "text",
                           label = T("Authorization Basis"),
                           readable = False,
                           writable = False,
                           ),
                     s3_comments(),
                     *s3_meta_fields())

        # Components
        self.add_components(tablename,
                            cap_authority_feed_url = {"name": "feed_url",
                                                      "joinby": "alerting_authority_id",
                                                      },
                            cap_authority_forecast_url = {"name": "forecast_url",
                                                          "joinby": "alerting_authority_id",
                                                          },
                            )

        # CRUD Form
        crud_form = S3SQLCustomForm("oid",
                                    "organisation_id",
                                    "country",
                                    "authorisation",
                                    S3SQLInlineComponent("feed_url",
                                                         fields = [("", "url")],
                                                         label = T("CAP Feed URL"),
                                                         name = "feed_url",
                                                         ),
                                    S3SQLInlineComponent("forecast_url",
                                                         fields = [("", "url")],
                                                         label = T("Forecast URL"),
                                                         name = "forecast_url",
                                                         ),
                                    )

        # List Fields
        list_fields = ["oid",
                       "organisation_id",
                       "country",
                       "feed_url.url",
                       "forecast_url.url",
                       ]

        # Table Configuration
        self.configure(tablename,
                       crud_form = crud_form,
                       list_fields = list_fields,
                       )

        # CRUD Strings
        crud_strings[tablename] = Storage(
            label_create = T("Add Alerting Authority"),
            title_display = T("Alerting Authority"),
            title_list = T("Alerting Authorities"),
            title_update = T("Edit Alerting Authority"),
            subtitle_list = T("List Alerting Authorities"),
            label_list_button = T("List Alerting Authorities"),
            label_delete_button = T("Delete Alerting Authority"),
            msg_record_created = T("Alerting Authority added"),
            msg_record_modified = T("Alerting Authority updated"),
            msg_record_deleted = T("Alerting Authority deleted"),
            msg_list_empty = T("No Alerting Authority available"),
            )

        # Reusable Field
        represent = S3Represent(lookup = tablename,
                                fields = ["organisation_id", "oid"],
                                field_sep = " - ",
                                )

        authority_id = S3ReusableField("alerting_authority_id", "reference %s" % tablename,
                                       label = T("CAP Alerting Authority"),
                                       ondelete = "CASCADE",
                                       represent = represent,
                                       requires = IS_EMPTY_OR(
                                                    IS_ONE_OF(db, "%s.id" % tablename,
                                                              represent,
                                                              )),
                                       )

        # ---------------------------------------------------------------------
        # Feed URL for CAP Alerting Authority
        #
        tablename = "cap_authority_feed_url"
        define_table(tablename,
                     authority_id(),
                     # @ToDo: Add username and pwd for url
                     Field("url",
                           label = T("CAP Feed URL"),
                           requires = IS_EMPTY_OR(IS_URL()),
                           ),
                     *s3_meta_fields())

        # ---------------------------------------------------------------------
        # Forecasts URL for CAP Alerting Authority
        #
        tablename = "cap_authority_forecast_url"
        define_table(tablename,
                     authority_id(),
                     Field("url",
                           label = T("Forecast URL"),
                           requires = IS_EMPTY_OR(IS_URL()),
                           ),
                     *s3_meta_fields())

        # ---------------------------------------------------------------------
        # Pass names back to global scope (s3.*)
        return {}

    # -------------------------------------------------------------------------
    @staticmethod
    def defaults():
        """
            Return safe defaults in case the model has been deactivated.
        """

        return {}

# =============================================================================
class CAPMessageModel(S3Model):
    """ Link Alerts to Messages """

    names = ("cap_alert_message",
             )

    def model(self):

        # ---------------------------------------------------------------------
        # Alert <> Messages link table
        #
        tablename = "cap_alert_message"
        self.define_table(tablename,
                          self.cap_alert_id(empty = False,
                                            ondelete = "CASCADE",
                                            ),
                          self.msg_message_id(empty = False,
                                              ondelete = "CASCADE",
                                              ),
                          *s3_meta_fields())

        # ---------------------------------------------------------------------
        # Pass names back to global scope (s3.*)
        #
        return {}

    # -------------------------------------------------------------------------
    @staticmethod
    def defaults():
        """
            Return safe defaults in case the model has been deactivated.
        """

        return {}

# =============================================================================
def list_string_represent(value, fmt=lambda v: v):
    """
        Represent a list:string field value as comma-separated list

        @param value: the field value
        @param fmt: callable to format each list element (optional)

        @returns: the comma-separated list as string
    """

    if isinstance(value, list):
        output = ", ".join([fmt(i) for i in value])
    elif isinstance(value, str):
        try:
            output = ", ".join([fmt(i) for i in value[1:-1].split("|")])
        except IndexError:
            output = current.messages.UNKNOWN_OPT
    else:
        output = ""

    return output

# -------------------------------------------------------------------------
def cap_expirydate():
    """
        Default expiry date for info segments based on setting

        @returns: datetime.datetime, or None if setting is falsy
    """

    interval = current.deployment_settings.get_cap_info_effective_period()
    if interval:
        expiry_date = current.request.utcnow + datetime.timedelta(days=interval)
    else:
        # Automatic expiry disabled
        expiry_date = None
    return expiry_date

# -------------------------------------------------------------------------
def cap_sendername():
    """
        Default sender name for alerts
        - sender name is the name of the organisation if user is
          associated with one, otherwise the user email

        @returns: the sender name
    """

    db = current.db

    utable = db.auth_user
    otable = current.s3db.org_organisation

    sender = None

    user = current.auth.user
    if user:
        query = (utable.id == user.id) & \
                (utable.organisation_id == otable.id) & \
                (otable.deleted == False)

        org = db(query).select(otable.name, limitby=(0, 1)).first()
        if org:
            sender = org.name
        else:
            #sender = user.username # not globally unique
            sender = user.email

    return sender

# =============================================================================
def get_cap_alert_addresses_opts():
    """
        Get selectable options for the cap_alert.addresses field
        - currently uses pr_group as selectable recipients, and
          pr_group.id as identifier
        - however, neither the pr_group.id or the pr_group.name are
          valid addresses or identifiers in the sense of cap:addresses
        - a possible solution to produce an addresses-list from an
          internal selection of recipients could be to introduce a
          separate "recipients" field (list:reference pr_pentity),
          and translate it into an addresses-list onaccept (TODO)

        @returns: list of tuples (id, translated_group_name)
    """

    T = current.T

    gtable = current.s3db.pr_group
    rows = current.db(gtable.deleted == False).select(gtable.id,
                                                      gtable.name,
                                                      )
    return [(row.id, s3_str(T(row.name))) for row in rows]

# =============================================================================
def cap_alert_is_template(alert_id):
    """
        Check whether a cap_alert is a template

        @param alert_id: the alert record ID

        @returns: True|False whether the alert is a template
    """

    if not alert_id:
        return False

    table = current.s3db.cap_alert
    alert = current.db(table.id == alert_id).select(table.is_template,
                                                    limitby = (0, 1),
                                                    ).first()
    return bool(alert.is_template) if alert else False

# =============================================================================
def cap_rheader(r, tabs=None):
    """ CAP Module Resource Headers """

    if r.representation != "html":
        # Resource headers only used in interactive views
        return None

    tablename, record = s3_rheader_resource(r)
    #if tablename != r.tablename:
    #    resource = current.s3db.resource(tablename, id=record.id)
    #else:
    #    resource = r.resource

    rheader = None

    if record:

        record_id = record.id

        T = current.T
        db = current.db
        s3db = current.s3db
        settings = current.deployment_settings

        tablename = r.tablename
        if tablename == "cap_alert":

            # Check for info segment
            itable = s3db.cap_info
            row = db(itable.alert_id == record_id).select(itable.id,
                                                          limitby = (0, 1),
                                                          ).first()
            if record.is_template:
                # Default tabs
                if not tabs:
                    tabs = [(T("Alert Details"), None),
                            (T("Information"), "info"),
                            #(T("Area"), "area"),
                            (T("Resource Files"), "resource"),
                            ]
                rheader_tabs = s3_rheader_tabs(r, tabs)

                # Hint for missing info segment
                if not row:
                    error = DIV(T("An alert needs to contain at least one info item."),
                                _class = "error",
                                )
                else:
                    error = ""

                # The rheader
                rheader = DIV(TABLE(TR(TH("%s: " % T("Template Title")),
                                       TD(A(CAPAlertModel.template_represent(record_id, record),
                                            _href = URL(c="cap", f="template",
                                                        args = [record_id, "update"],
                                                        ),
                                            ),
                                          ),
                                       ),
                                    TR(TH("%s: " % T("Event Type")),
                                       TD(r.table.event_type_id.represent(record.event_type_id)),
                                       ),
                                    ),
                              rheader_tabs,
                              error,
                              )
            else:
                has_permission = current.auth.s3_has_permission

                action_btn = None
                msg_type_buttons = None

                if not row:
                    # Hint for missing INFO-segment
                    error = DIV(T("You need to create at least one alert information item in order to be able to broadcast this alert!"),
                                _class="error")
                else:
                    error = ""

                    # Action buttons for Alerts
                    # TODO clean up and move into separate function(s)

                    # Display 'Submit for Approval', 'Publish Alert' or 'Review Alert'
                    # based on permission and deployment settings
                    if not current.request.get_vars.get("_next") and \
                       settings.get_cap_authorisation() and \
                       record.approved_by is None:

                        # Show these buttons only if there is at least one area segment
                        area_table = s3db.cap_area
                        area_row = db(area_table.alert_id == record_id).select(area_table.id, limitby=(0, 1)).first()
                        if area_row and has_permission("update", "cap_alert", record_id=record_id):
                            action_btn = A(T("Submit for Approval"),
                                           _href = URL(f = "notify_approver",
                                                       vars = {"cap_alert.id": record_id,
                                                               },
                                                       ),
                                           _class = "action-btn confirm-btn button tiny"
                                           )
                            current.response.s3.jquery_ready.append('''S3.confirmClick('.confirm-btn','%s')''' % T("Do you want to submit the alert for approval?"))

                            # For Alert Approver
                            if has_permission("approve", "cap_alert"):
                                action_btn = A(T("Review Alert"),
                                               _href = URL(args = [record_id,
                                                                   "review"
                                                                   ],
                                                           ),
                                               _class = "action-btn button tiny",
                                               )

                    # 'Relay Alert' action button
                    if record.approved_by is not None:
                        if has_permission("create", "cap_alert"):
                            relay_alert = A(T("Relay Alert"),
                                            _data = "%s/%s" % (record.msg_type, r.id),
                                            _class = "action-btn cap-clone-update button tiny",
                                            )
                            if record.external:
                                msg_type_buttons = relay_alert
                            else:
                                if record.created_by:
                                    utable = db.auth_user
                                    row = db(utable.id == record.created_by).select(
                                                            utable.organisation_id,
                                                            limitby = (0, 1),
                                                            ).first()
                                    row_ = db(utable.id == current.auth.user.id).select(
                                                            utable.organisation_id,
                                                            limitby = (0, 1),
                                                            ).first()
                                    if row.organisation_id == row_.organisation_id:
                                        # Same organisation
                                        msg_type = record.msg_type
                                        if msg_type == "Alert" or msg_type == "Update":
                                            msg_type_buttons = TAG[""](
                                                    TR(TD(A(T("Update Alert"),
                                                            _data = "Update/%s" % r.id,
                                                            _class = "action-btn cap-clone-update button tiny",
                                                            ))),
                                                    TR(TD(A(T("Cancel Alert"),
                                                            _data = "Cancel/%s" % r.id,
                                                            _class = "action-btn cap-clone-update button tiny",
                                                            ))),
                                                    TR(TD(A(T("Error Alert"),
                                                            _data = "Error/%s" % r.id,
                                                            _class = "action-btn cap-clone-update button tiny",
                                                            ))),
                                                    #TR(TD(A(T("All Clear"),
                                                    #        _data = "AllClear/%s" % r.id,
                                                    #        _class = "action-btn cap-clone-update button tiny",
                                                    #        ))),
                                                    )
                                        elif msg_type == "Error":
                                            msg_type_buttons = TAG[""](
                                                    TR(TD(A(T("Update Alert"),
                                                            _data = "Update/%s" % r.id,
                                                            _class = "action-btn cap-clone-update button tiny",
                                                            ))),
                                                    #TR(TD(A(T("All Clear"),
                                                    #        _data = "AllClear/%s" % r.id,
                                                    #        _class = "action-btn cap-clone-update button tiny",
                                                    #        ))),
                                                    )
                                        else:
                                            msg_type_buttons = None
                                    else:
                                        # Different organisation
                                        msg_type_buttons = relay_alert
                                else:
                                    msg_type_buttons = relay_alert

                # Default tabs
                if not tabs:
                    tabs = [(T("Alert Details"), None),
                            (T("Information"), "info"),
                            (T("Area"), "area"),
                            (T("Resource Files"), "resource"),
                            ]

                    # Additional tabs
                    if r.representation == "html" and \
                       has_permission("update", "cap_alert", record_id=record_id) and \
                       r.record.approved_by is None:

                        # Show predefined areas tab if we have some defined for this event_type
                        row_ = db(itable.alert_id == record_id).select(itable.event_type_id,
                                                                       limitby = (0, 1),
                                                                       ).first()
                        if row_ is not None:
                            artable = s3db.cap_area
                            query = (artable.deleted == False) & \
                                    (artable.is_template == True) & \
                                    (artable.event_type_id == row_.event_type_id)
                            template_area_row = db(query).select(artable.id,
                                                                 limitby = (0, 1),
                                                                 ).first()
                            if template_area_row:
                                tabs.insert(2, (T("Predefined Areas"), "assign"))

                rheader_tabs = s3_rheader_tabs(r, tabs)

                # The rheader
                rheader = DIV(TABLE(TR(TH("%s: " % T("Alert")),
                                       TD(A("%s - %s" % (record.identifier, record.sender),
                                            _href = URL(c="cap", f="alert",
                                                        args = [record_id, "update"],
                                                        ),
                                            ),
                                          ),
                                       ),
                                    #TR(export_btn)
                                    ),
                              rheader_tabs,
                              error,
                              )

                # Insert buttons
                if action_btn:
                    rheader.insert(1, TR(TD(action_btn)))

                if msg_type_buttons is not None:
                    rheader.insert(1, msg_type_buttons)

        elif tablename == "cap_area":
            # Used only for Area Templates

            # Default tabs
            if not tabs:
                tabs = [(T("Area"), None),
                        ]
                if settings.get_L10n_translate_cap_area():
                    tabs.insert(1, (T("Local Names"), "name"))
            rheader_tabs = s3_rheader_tabs(r, tabs)

            # The rheader
            rheader = DIV(TABLE(TR(TH("%s: " % T("Area")),
                                   TD(A(s3db.cap_area_represent(record.id, record),
                                        _href = URL(c="cap", f="area",
                                                    args = [record.id, "update"],
                                                    ),
                                        ),
                                      ),
                                   ),
                                ),
                          rheader_tabs,
                          )

        elif tablename == "cap_info":

            is_template = cap_alert_is_template(record.alert_id)

            # Default tabs
            if not tabs:
                tabs = [(T("Information"), None),
                        (T("Resource Files"), "resource"),
                        ]
            if not is_template:
                tabs.insert(1, (T("Areas"), "area"))
            rheader_tabs = s3_rheader_tabs(r, tabs)

            # The rheader
            if is_template:
                rheader = DIV(TABLE(TR(TH("%s: " % T("Template")),
                                       TD(A(CAPAlertModel.template_represent(record.alert_id),
                                            _href = URL(c="cap", f="template",
                                                        args = [record.alert_id, "update"],
                                                        ),
                                            ),
                                          ),
                                        ),
                                    TR(TH("%s: " % T("Info template")),
                                       TD(A(s3db.cap_info_represent(record.id, record),
                                            _href = URL(c="cap", f="info",
                                                        args = [record.id, "update"],
                                                        ),
                                            ),
                                          ),
                                       ),
                                    ),
                              rheader_tabs,
                              _class="cap_info_template_form"
                              )
                current.response.s3.js_global.append('''i18n.cap_locked="%s"''' % T("Locked"))
            else:
                rheader = DIV(TABLE(TR(TH("%s: " % T("Alert")),
                                       TD(A(s3db.cap_alert_represent(record.alert_id),
                                            _href = URL(c="cap", f="alert",
                                                        args = [record.alert_id, "update"],
                                                        ),
                                            ),
                                          ),
                                       ),
                                    TR(TH("%s: " % T("Information")),
                                       TD(A(s3db.cap_info_represent(record.id, record),
                                            _href = URL(c="cap", f="info",
                                                        args = [record.id, "update"],
                                                        ),
                                            ),
                                          ),
                                       ),
                                    ),
                              rheader_tabs,
                              )

    return rheader

# =============================================================================
def cap_history_rheader(r, tabs=None):
    """ Resource Header for CAP history tables """

    if r.representation != "html":
        # Resource headers only used in interactive views
        return None

    tablename, record = s3_rheader_resource(r)

    rheader = None
    if record:

        T = current.T
        s3db = current.s3db

        if tablename == "cap_alert_history":
            alert_id = record.id

            # Default tabs
            if not tabs:
                tabs = [(T("Alert Details"), None),
                        (T("Information"), "info_history"),
                        (T("Area"), "area_history"),
                        (T("Resource Files"), "resource_history"),
                        ]

            rheader_tabs = s3_rheader_tabs(r, tabs)

            # The rheader
            rheader = DIV(TABLE(TR(TH("%s: " % T("Alert")),
                                   TD(A(s3db.cap_alert_represent(alert_id, record),
                                        _href = URL(c="cap", f="alert",
                                                    args=[alert_id, "update"],
                                                    ),
                                        ),
                                      ),
                                   ),
                                ),
                          rheader_tabs,
                          )

    return rheader

# =============================================================================
def cap_alert_list_layout(list_id, item_id, resource, rfields, record):
    """
        Default dataList item renderer for CAP Alerts on the Home page.

        @param list_id: the HTML ID of the list
        @param item_id: the HTML ID of the item
        @param resource: the S3Resource to render
        @param rfields: the S3ResourceFields to render
        @param record: the record as dict
    """

    record_id = record["cap_alert.id"]
    item_class = "thumbnail"

    T = current.T
    #raw = record._row
    # @ToDo: handle the case where we have multiple info segments &/or areas
    headline = record["cap_info.headline"]
    location = s3_str(record["cap_area.name"])
    priority = record["cap_info.priority"]
    status = record["cap_alert.status"]
    scope = record["cap_alert.scope"]
    event = record["cap_info.event_type_id"]
    msg_type = s3_str(record["cap_alert.msg_type"])

    if current.auth.s3_logged_in():
        _href = URL(c="cap", f="alert", args=[record_id, "profile"])
    else:
        _href = URL(c="cap", f="public", args=[record_id, "profile"])

    priority_row = None
    if priority and priority != "-":
        # Give the priority color to headline
        db = current.db
        wptable = db.cap_warning_priority
        priority_row = db(wptable.name == priority).select(wptable.color_code,
                                                           limitby = (0, 1),
                                                           ).first()

    more = A(T("Full Alert"),
             _href = _href,
             _target = "_blank",
             )

    if list_id == "map_popup":
        itable = current.s3db.cap_info
        # Map popup
        event = itable.event_type_id.represent(event)
        if priority is None:
            priority = ""
        else:
            priority = itable.priority.represent(priority)
        description = record["cap_info.description"]
        response_type = record["cap_info.response_type"]
        sender = record["cap_info.sender_name"]
        last = TAG[""](BR(),
                       description,
                       BR(),
                       ", ".join(response_type) if response_type is not None else None,
                       BR(),
                       sender,
                       BR(),
                       )

        details = "%s %s %s" % (priority, status, scope)

        headline_ = A(headline,
                      _href = _href,
                      _target = "_blank",
                      )

        if priority_row:
            headline_["_style"] = "color: #%s" % (priority_row.color_code)

        item = DIV(headline_,
                   BR(),
                   location,
                   BR(),
                   details,
                   BR(),
                   event,
                   last,
                   more,
                   _class=item_class,
                   _id=item_id,
                   )
    else:
        if priority == current.messages["NONE"]:
            priority = ""
        sender_name = record["cap_info.sender_name"]
        sent = record["cap_alert.sent"]

        headline = "%s" % (headline)

        sub_heading = "%s %s %s" % (priority, event, msg_type)

        sub_headline = A(sub_heading,
                         _href = _href,
                         _target = "_blank",
                         )

        if priority_row:
            sub_headline["_style"] = "color: #%s" % (priority_row.color_code)

        para = T("%(status)s alert for %(area_description)s.") % \
                    {"status": status, "area_description": location}

        issuer = "%s: %s" % (T("Issued by"), sender_name)
        issue_date = "%s: %s" % (T("Issued on"), sent)

        item = DIV(headline,
                   BR(),
                   para,
                   BR(),
                   sub_headline,
                   BR(),
                   issuer,
                   BR(),
                   issue_date,
                   BR(),
                   more,
                   _class=item_class,
                   _id=item_id,
                   )

    return item

# =============================================================================
class cap_AreaRepresent(S3Represent):
    """ Representation of CAP Area """

    def __init__(self, show_link=False, multiple=False):

        settings = current.deployment_settings

        # Translation using cap_area_name & not T()
        translate = settings.get_L10n_translate_cap_area()
        if translate:
            language = current.session.s3.language
            if language == settings.get_L10n_default_language():
                translate = False

        super(cap_AreaRepresent, self).__init__(lookup = "cap_area",
                                                show_link = show_link,
                                                translate = translate,
                                                multiple = multiple,
                                                )

    # -------------------------------------------------------------------------
    def lookup_rows(self, key, values, fields=None):
        """
            Custom lookup method for area Rows; to look up local name if
            required.

            @param key: unused (retained for API compatibility)
            @param values: the cap_area IDs
            @param fields: unused (retained for API compatibility)
        """

        table = self.table

        count = len(values)
        if count == 1:
            query = (table.id == values[0])
        else:
            query = (table.id.belongs(values))

        fields = [table.id, table.name]
        if self.translate:
            ltable = current.s3db.cap_area_name
            fields.append(ltable.name_l10n)
            left = ltable.on((ltable.area_id == table.id) & \
                             (ltable.language == current.session.s3.language))
        else:
            left = None

        rows = current.db(query).select(left=left, limitby=(0, count), *fields)
        return rows

    # -------------------------------------------------------------------------
    def represent_row(self, row):
        """
            Represent a single Row

            @param row: the cap_area Row
        """

        name = row["cap_area.name"]

        if self.translate:
            local_name = row["cap_area_name.name_l10n"]
            if local_name:
                name = local_name

        return s3_str(name) if name else self.default

# =============================================================================
class cap_ImportAlert(S3Method):
    """
        Simple interactive CAP-XML Alert importer
        - designed as REST method for the cap_alert resource
    """

    # -------------------------------------------------------------------------
    def apply_method(self, r, **attr):
        """
            Apply method.

            @param r: the S3Request
            @param attr: controller options for this request
        """

        # Requires permission to create alerts
        authorised = current.auth.s3_has_permission("create", "cap_alert")
        if not authorised:
            r.unauthorised()

        output = None

        if r.representation == "html":

            T = current.T
            response = current.response

            fields = [Field("url",
                            label=T("URL"),
                            requires=[IS_NOT_EMPTY(),
                                      IS_URL(mode="generic"),
                                      ],
                            comment = DIV(_class="tooltip",
                                         _title="%s|%s" % (T("URL of the alert"),
                                                           T("The URL from which the alert should be imported!"))),
                            ),
                      Field("user",
                            label=T("Username"),
                            comment = DIV(_class="tooltip",
                                          _title="%s|%s" % (T("Username"),
                                                            T("Optional username for HTTP Authentication."))),
                            ),
                      Field("password",
                            label=T("Password"),
                            widget = S3PasswordWidget(),
                            comment = DIV(_class="tooltip",
                                          _title="%s|%s" % (T("Password"),
                                                            T("Optional password for HTTP Authentication."))),
                            ),
                      # TODO This is pointless:
                      #Field("ignore_errors", "boolean",
                      #      label=T("Ignore Errors?"),
                      #      represent = s3_yes_no_represent,
                      #      comment = DIV(_class="tooltip",
                      #                    _title="%s|%s" % (T("Ignore Errors"),
                      #                                      T("skip invalid record silently?"))),
                      #      ),
                      ]
            labels, required = s3_mark_required(fields)
            response.s3.has_required = required

            response.form_label_separator = ""
            form = SQLFORM.factory(formstyle = current.deployment_settings.get_ui_formstyle(),
                                   submit_button = T("Import"),
                                   labels = labels,
                                   separator = "",
                                   table_name = "import_alert", # Dummy table name
                                   _id = "importform",
                                   *fields
                                   )

            response.view = "create.html"
            output = {"title": T("Import from Feed URL"),
                      "form": form,
                      }

            if form.accepts(r.post_vars,
                            current.session,
                            formname = "import_form",
                            ):

                resource = r.resource
                error, msg = self.accept(resource, form)

                if error:
                    response.error = error
                else:
                    if msg:
                        response.confirmation = msg

                        # Get the ID of the newly created/updated cap_alert
                        if resource.import_created:
                            alert_id = resource.import_created[0]
                        elif resource.import_updated:
                            alert_id = resource.import_updated[0]
                        else:
                            alert_id = None

                        # Forward to a view of the alert
                        if alert_id:
                            self.next = URL(c="cap", f="alert", args=[alert_id])
                        else:
                            self.next = URL(c="cap", f="alert")
                    else:
                        response.warning = T("No CAP alerts found at URL")

        else:
            r.error(405, current.ERROR.BAD_METHOD)

        return output

    # -------------------------------------------------------------------------
    def accept(self, resource, form):
        """
            Accept the import-form

            @param resource: the target import resource
            @param form: the FORM
            @returns: tuple (error, msg)
                      error - error message (if an error occured)
                      msg - confirmation message of the import
        """

        formvars_get = form.vars.get

        url = formvars_get("url")
        opener = self.opener(url,
                             username = formvars_get("user"),
                             password = formvars_get("password"),
                             )

        tree = version = error = None
        try:
            content = opener.open(url)
        except HTTPError as e:
            # HTTP status
            error = "HTTP %s: %s" % (e.code, e.read())
        except URLError as e:
            # URL Error (network error)
            error = "CAP source unavailable (%s)" % e.reason
        except Exception:
            # Other error (local error)
            import sys
            error = sys.exc_info()[1]
        else:
            # Try parse
            tree, version, error = self.parse_cap(content)

        if tree:
            error, msg = self.import_cap(tree,
                                         version = version,
                                         resource = resource,
                                         url = url,
                                         # TODO Pointless:
                                         #ignore_errors = formvars_get("ignore_errors", False),
                                         )
        else:
            msg = None

        return error, msg

    # -------------------------------------------------------------------------
    @staticmethod
    def import_cap(tree, version=None, resource=None, url=None, ignore_errors=False):
        """
            Import a CAP-XML element tree into a cap_alert resource

            @param tree: the ElementTree
            @param version: the detected CAP version (see parse_cap)
            @param resource: the cap_alert resource to import to,
                             will be instantiated if not passed in
            @param url: the CAP-XML source URL
            @param ignore_errors: skip invalid cap_alert records

            TODO ignore_errors gives no benefit because it means to
                 skip invalid master records, but a CAP-XML source
                 can only contain one master record anyway - so the
                 outcome would be the same
        """

        msg = None
        s3db = current.s3db

        # Version-specific import transformation stylesheet?
        if version == "cap11":
            filename = "import11.xsl"
        else:
            # Default CAP-1.2
            filename = "import.xsl"
        stylesheet = os.path.join(current.request.folder,
                                  "static", "formats", "cap", filename,
                                  )

        # Set default for cap_info.web
        itable = s3db.table("cap_info")
        field = itable.web
        field.default = url or None

        # Import the CAP-XML
        if resource is None:
            resource = s3db.resource("cap_alert")
        try:
            resource.import_xml(tree,
                                stylesheet = stylesheet,
                                ignore_errors = ignore_errors,
                                )
        except (IOError, SyntaxError):
            import sys
            error = "CAP import error: %s" % sys.exc_info()[1]
        else:
            if resource.error:
                # Import validation error
                errors = current.xml.collect_errors(resource.error_tree)
                error = "%s\n%s" % (resource.error, "\n".join(errors))
            else:
                error = None

            if resource.import_count == 0:
                if not error:
                    # No error, but nothing imported either
                    error = "No CAP alerts found in source"
            else:
                # Success
                error = None
                msg = "%s new CAP alerts imported, %s alerts updated" % (
                        len(resource.import_created),
                        len(resource.import_updated))

        return error, msg

    # -------------------------------------------------------------------------
    @staticmethod
    def parse_cap(source):
        """
            Parse a CAP-XML source and detect the CAP version

            @param source: the CAP-XML source

            @returns: tuple (tree, version, error)
                      - tree    = ElementTree of the CAP source
                      - version = the detected CAP version
                      - error   = error message if parsing failed, else None
        """

        version = error = None

        xml = current.xml

        # Attempt to parse the source
        tree = xml.parse(source)

        if not tree:
            # Capture parser error
            error = xml.error or "XML parsing failed"

        else:
            # All supported CAP versions and their namespace URIs
            namespaces = (("cap11", "urn:oasis:names:tc:emergency:cap:1.1"),
                          ("cap12", "urn:oasis:names:tc:emergency:cap:1.2"),
                          )

            # Default
            version = "cap12"

            root = tree.getroot()
            for ns, uri in namespaces:
                if root.xpath("/%s:alert[1]" % ns, namespaces = {ns: uri}):
                    version = ns
                    break

        return tree, version, error

    # -------------------------------------------------------------------------
    @staticmethod
    def opener(url,
               headers=None,
               username=None,
               password=None,
               preemptive_auth=False,
               proxy=None,
               ):
        """
            Configure a HTTP opener to fetch CAP messages

            @param url: the target URL
            @param headers: HTTP request headers, list of tuples (header, value)
            @param username: user name for auth
            @param password: password for auth
            @param preemptive_auth: send credentials without waiting for a
                                    HTTP401 challenge
            @param proxy: proxy URL (if required)

            @returns: an OpenerDirector instance with proxy and
                      auth handlers installed

            @example:
                url = "http://example.com/capfile.xml"
                opener = self._opener(url, username="user", password="password")
                content = opener.open(url)
        """

        # Configure opener headers
        addheaders = []
        if headers:
            addheaders.extend(headers)

        # Configure opener handlers
        handlers = []

        # Proxy handling
        if proxy:
            # Figure out the protocol from the URL
            url_split = url.split("://", 1)
            if len(url_split) == 2:
                protocol = url_split[0]
            else:
                protocol = "http"
            proxy_handler = urllib2.ProxyHandler({protocol: proxy})
            handlers.append(proxy_handler)

        # Authentication handling
        if username and password:
            # Add a 401 handler
            passwd_manager = urllib2.HTTPPasswordMgrWithDefaultRealm()
            passwd_manager.add_password(realm = None,
                                        uri = url,
                                        user = username,
                                        passwd = password,
                                        )
            auth_handler = urllib2.HTTPBasicAuthHandler(passwd_manager)
            handlers.append(auth_handler)

        # Create the opener
        opener = urllib2.build_opener(*handlers)

        # Pre-emptive basic auth
        if preemptive_auth and username and password:
            import base64
            base64string = base64.encodestring('%s:%s' % (username, password))[:-1]
            addheaders.append(("Authorization", "Basic %s" % base64string))

        if addheaders:
            opener.addheaders = addheaders

        return opener

# -----------------------------------------------------------------------------
class cap_AssignArea(S3Method):
    """
        Assign CAP area to an alert, allows (multi-)selection of Predefined areas
    """

    def apply_method(self, r, **attr):
        """
            Apply method.
            @param r: the S3Request
            @param attr: controller options for this request
        """

        if not r.record:
            # Must be called for a particular alert
            r.error(404, current.ERROR.BAD_RECORD)

        # The record ID of the alert the method is called for
        alert_id = r.id

        # Requires permission to update this alert
        authorised = current.auth.s3_has_permission("update", "cap_alert",
                                                    record_id=alert_id)
        if not authorised:
            r.unauthorised()

        T = current.T
        s3db = current.s3db
        response = current.response

        # Get the event_type_id to filter by
        itable = s3db.cap_info
        row = current.db(itable.alert_id == alert_id).\
                    select(itable.event_type_id, limitby=(0, 1)).first()

        # Filter to limit the selection of areas
        area_filter = (FS("is_template") == True) & (FS("event_type_id") == row.event_type_id)

        if r.http == "POST":
            # Template areas have been selected

            added = 0
            post_vars = r.post_vars

            if all([n in post_vars for n in ("assign", "selected", "mode")]):

                selected = post_vars.selected
                if selected:
                    selected = selected.split(",")
                else:
                    selected = []

                # Handle exclusion filter
                if post_vars.mode == "Exclusive":

                    # URL filters
                    if "filterURL" in post_vars:
                        filters = S3URLQuery.parse_url(post_vars.ajaxURL)
                    else:
                        filters = None

                    query = area_filter & (~(FS("id").belongs(selected)))
                    aresource = s3db.resource("cap_area",
                                              filter = query,
                                              vars = filters)
                    rows = aresource.select(["id"], as_rows=True)
                    selected = [str(row.id) for row in rows]

                for area_id in selected:
                    area_id = int(area_id.strip())
                    self.add_area_from_template(area_id, alert_id)
                    added += 1
            if added == 1:
                confirm_text = T("1 area assigned")
            elif added > 1:
                confirm_text = T("%(number)s areas assigned") % {"number": added}
            current.session.confirmation = confirm_text
            if added > 0:
                # Redirect to the list of areas of this alert
                redirect(URL(args=[r.id, "area"], vars={}))
            else:
                # Return to the "assign" page
                redirect(URL(args=r.args, vars={}))

        elif r.http == "GET":

            # Filter widgets (@todo: lookup from cap_area resource config?)
            filter_widgets = []

            # List fields
            list_fields = ["id",
                           "name",
                           "event_type_id",
                           #"priority",
                           ]

            # Data table
            aresource = s3db.resource("cap_area", filter=area_filter)
            totalrows = aresource.count()
            get_vars = r.get_vars
            if "pageLength" in get_vars:
                display_length = get_vars["pageLength"]
                if display_length == "None":
                    display_length = None
                else:
                    display_length = int(display_length)
            else:
                display_length = 25
            if display_length:
                limit = 4 * display_length
            else:
                limit = None

            # Datatable filter and sorting
            query, orderby, left = aresource.datatable_filter(list_fields,
                                                              get_vars,
                                                              )
            aresource.add_filter(query)

            # Extract the data
            data = aresource.select(list_fields,
                                    start = 0,
                                    limit = limit,
                                    orderby = orderby,
                                    left = left,
                                    count = True,
                                    represent = True,
                                    )
            filteredrows = data.numrows

            # Instantiate the datatable
            dt = S3DataTable(data.rfields, data.rows)
            dt_id = "datatable"

            # Bulk actions
            dt_bulk_actions = [(T("Assign"), "assign")]

            if r.representation == "html":
                # Page load

                # Disallow deletion from this table, and link all open-buttons
                # to the respective area read page
                aresource.configure(deletable = False)
                profile_url = URL(c = "cap",
                                  f = "area",
                                  args = ["[id]", "read"],
                                  )
                S3CRUD.action_buttons(r,
                                      deletable = False,
                                      read_url = profile_url,
                                      update_url = profile_url,
                                      )
                # Hide export icons
                response.s3.no_formats = True

                # Render the datatable (will be "items" in the output dict)
                items = dt.html(totalrows,
                                filteredrows,
                                dt_id,
                                dt_ajax_url = URL(args = r.args,
                                                  extension="aadata",
                                                  vars={},
                                                  ),
                                dt_bulk_actions = dt_bulk_actions,
                                dt_pageLength = display_length,
                                dt_pagination = "true",
                                dt_searching = "false",
                                )

                # Filter form
                if filter_widgets:

                    # Where to retrieve filtered data from:
                    get_vars = aresource.crud._remove_filters(r.get_vars)
                    filter_submit_url = r.url(vars=get_vars)

                    # Where to retrieve updated filter options from:
                    filter_ajax_url = URL(f="cap_area",
                                          args=["filter.options"],
                                          vars={},
                                          )

                    get_config = aresource.get_config
                    filter_clear = get_config("filter_clear", True)
                    filter_formstyle = get_config("filter_formstyle", None)
                    filter_submit = get_config("filter_submit", True)
                    filter_form = S3FilterForm(filter_widgets,
                                               clear = filter_clear,
                                               formstyle = filter_formstyle,
                                               submit = filter_submit,
                                               ajax = True,
                                               url = filter_submit_url,
                                               ajaxurl = filter_ajax_url,
                                               _class = "filter-form",
                                               _id = "datatable-filter-form",
                                               )
                    fresource = s3db.resource("cap_area")
                    ff = filter_form.html(fresource,
                                          r.get_vars,
                                          target = "datatable",
                                          )
                else:
                    ff = ""

                output = {"items": items, # the datatable
                          "title": T("Add Areas"),
                          "list_filter_form": ff,
                          }
                response.view = "list_filter.html"
                return output

            elif r.representation == "aadata":
                # Ajax refresh
                if "draw" in get_vars:
                    echo = int(get_vars.draw)
                else:
                    echo = None
                items = dt.json(totalrows,
                                filteredrows,
                                dt_id,
                                echo,
                                dt_bulk_actions=dt_bulk_actions,
                                )
                response.headers["Content-Type"] = "application/json"
                return items

            else:
                r.error(415, current.ERROR.BAD_FORMAT)
        else:
            r.error(405, current.ERROR.BAD_METHOD)

    # -------------------------------------------------------------------------
    @staticmethod
    def add_area_from_template(template_area_id, alert_id):
        """
            Add a new area to an alert from a template area including
            location links and tags

            @param template_area_id: the template cap_area record ID
            @param alert_id: the record ID of the alert

            @returns: the new area record ID
        """

        db = current.db
        s3db = current.s3db

        set_record_owner = current.auth.s3_set_record_owner
        audit = current.audit
        #update_super = s3db.update_super
        onaccept = s3db.onaccept

        # Get the template
        atable = s3db.cap_area
        query = (atable.id == template_area_id) & \
                (atable.deleted == False)
        template_area = db(query).select(atable.name,
                                         atable.altitude,
                                         atable.ceiling,
                                         limitby = (0, 1),
                                         ).first()
        if not template_area:
            return None

        # Collect data for new area
        area = {"name": template_area.name,
                "is_template": False,
                "alert_id": alert_id,
                "template_area_id": template_area_id,
                "altitude": template_area.altitude,
                "ceiling": template_area.ceiling,
                }

        # Create new area
        area_id = atable.insert(**area)
        area["id"] = area_id

        # Post-process create
        audit("create", "cap", "area", record=area_id)
        #update_super(atable, area) # currently not required
        set_record_owner(atable, area_id)
        onaccept(atable, area)

        # Copy all location links from the template
        ltable = s3db.cap_area_location
        query = (ltable.area_id == template_area_id) & \
                (ltable.deleted == False)
        rows = db(query).select(ltable.location_id,
                                )
        for row in rows:
            link = {"area_id": area_id,
                    "alert_id": alert_id,
                    "location_id": row.location_id,
                    }
            link_id = ltable.insert(**link)
            link["id"] = link_id

            audit("create", "cap", "area_location", record=link_id)
            #update_super(ltable, link) # currently not required
            set_record_owner(ltable, link_id)
            onaccept(ltable, link)

        # Copy all tags from template
        ttable = s3db.cap_area_tag
        query = (ttable.area_id == template_area_id) & \
                (ttable.deleted == False)
        rows = db(query).select(ttable.tag,
                                ttable.value,
                                ttable.comments,
                                )
        for row in rows:
            tag = {"area_id": area_id,
                   "alert_id": alert_id,
                   "tag": row.tag,
                   "value": row.value,
                   "comments": row.comments,
                   }
            tag_id = ttable.insert(**tag)
            tag["id"] = tag_id

            audit("create", "cap", "area_tag", record=tag_id)
            #update_super(ttable, tag) # currently not required
            set_record_owner(ttable, tag_id)
            #onaccept(ttable, tag) # currently not required (redundant?)

        return area_id

# -----------------------------------------------------------------------------
class cap_CloneAlert(S3Method):
    """
        Clone the cap_alert
    """

    # -------------------------------------------------------------------------
    def apply_method(self, r, **attr):
        """
            Apply method

            @param r: the S3Request
            @param attr: controller options for this request
        """

        output = {}
        if r.http == "POST":
            if r.method == "clone":
                output = clone(r, **attr)
            else:
                r.error(405, current.ERROR.BAD_METHOD)
        else:
            r.error(405, current.ERROR.BAD_METHOD)
        return output

# -----------------------------------------------------------------------------
def clone(r, record=None, **attr):
    """
        Clone the cap_alert

        @param r: the S3Request instance
        @param record: the record row
        @param attr: controller attributes
    """
    # TODO make a class method of cap_CloneAlert

    if record and not r.env.request_method == "POST":
        current.log.error(current.ERROR.BAD_METHOD)
        return

    # Get the alert ID
    alert_id = r.id
    if not alert_id and record:
        alert_id = record.id

    if not alert_id:
        # Must be called for a particular alert
        if record:
            current.log.error(current.ERROR.BAD_RECORD)
        else:
            r.error(404, current.ERROR.BAD_RECORD)

    s3db = current.s3db
    alert_table = s3db.cap_alert
    # Get the person ID
    auth = current.auth
    person_id = auth.s3_logged_in_person()
    if not person_id or not auth.s3_has_permission("create", alert_table):
        auth.permission.fail()

    msg_type_options = ["Alert", "Update", "Cancel", "Error", "AllClear"]
    msg_type = current.request._get_vars["msg_type"]

    if msg_type and msg_type not in msg_type_options:
        r.error(400, current.ERROR.BAD_REQUEST)

    # Start of clone
    db = current.db
    alert_history_table = s3db.cap_alert_history
    info_table = s3db.cap_info
    area_table = s3db.cap_area
    location_table = s3db.cap_area_location
    tag_table = s3db.cap_area_tag
    resource_table = s3db.cap_resource
    unwanted_fields = ["id", "doc_id"]
    unwanted_fields.extend(s3_all_meta_field_names())
    if record:
        unwanted_fields = ["id", "alert_id", "info_id", "is_template", "doc_id"]
    unwanted_fields = set(unwanted_fields)
    accessible_query = auth.s3_accessible_query
    has_permission = auth.s3_has_permission
    audit = current.audit
    set_record_owner = auth.s3_set_record_owner
    onaccept = s3db.onaccept

    # Copy the alert segment
    alert_fields = [alert_table[f] for f in alert_table.fields
                    if f not in unwanted_fields]
    alert_query = (alert_table.id == alert_id) & \
                   accessible_query("read", alert_table)
    alert_row = db(alert_query).select(*alert_fields, limitby=(0, 1)).first()
    alert_row_clone = alert_row.as_dict()
    if record:
        # Alert History use-case
        alert_row_clone["event_type"] = alert_table.event_type_id.represent(alert_row_clone["event_type_id"])
        del alert_row_clone["event_type_id"]
        del alert_row_clone["template_id"]
        del alert_row_clone["template_title"]
        del alert_row_clone["template_settings"]
        del alert_row_clone["external"]

        new_alert_id = alert_history_table.insert(**alert_row_clone)
        # Post-process create
        alert_row_clone["id"] = new_alert_id
        audit("create", "cap", "alert_history", record=new_alert_id)
        set_record_owner(alert_history_table, new_alert_id)
    else:
        # Change of msg_type use-case or relay alert
        referenced_reference = alert_row.reference
        references = []
        if referenced_reference:
            reference_splits = referenced_reference.split(",")
            reference_query_ = (alert_table.deleted == False) & \
                               (alert_table.is_template != True) & \
                               (alert_table.external != True)
            for split in reference_splits:
                reference_query = reference_query_ & (alert_table.identifier == split)
                reference_row = db(reference_query).select(alert_table.sender,
                                                           alert_table.sent,
                                                           limitby = (0, 1),
                                                           ).first()
                if reference_row:
                    references.append(("%s,%s,%s") % (reference_row.sender,
                                                      split,
                              s3_str(s3_utc(reference_row.sent)).replace(" ", "T")))

        references.append(("%s,%s,%s") % (alert_row.sender,
                                          alert_row.identifier,
                                s3_str(s3_utc(alert_row.sent)).replace(" ", "T")))
        del alert_row_clone["identifier"]
        alert_row_clone["msg_type"] = msg_type
        alert_row_clone["sent"] = current.request.utcnow
        alert_row_clone["external"] = False
        alert_row_clone["approved_on"] = None
        alert_row_clone["reference"] = " ".join(references)
        try:
            user_email = auth.user.email
        except AttributeError:
            user_email = ""
        alert_row_clone["sender"] = "%s" % user_email

        new_alert_id = alert_table.insert(**alert_row_clone)
        # Post-process create
        alert_row_clone["id"] = new_alert_id
        audit("create", "cap", "alert", record=new_alert_id)
        set_record_owner(alert_table, new_alert_id)
        onaccept(alert_table, alert_row_clone)

    if has_permission("create", info_table):
        # Copy the info segment
        info_history_table = s3db.cap_info_history
        unwanted_fields_ = list(unwanted_fields)
        unwanted_fields_.remove("id")
        info_fields = [info_table[f] for f in info_table.fields
                       if f not in unwanted_fields_]
        info_query = (info_table.alert_id == alert_id) &\
                      accessible_query("read", info_table)
        info_rows = db(info_query).select(*info_fields)
        if len(info_rows):
            info_parameter_table = s3db.cap_info_parameter
            info_parameter_history_table = s3db.cap_info_parameter_history
            info_parameter_table_insert = info_parameter_table.insert
            info_parameter_history_table_insert = info_parameter_history_table.insert
            info_parameter_accessible = accessible_query("read", info_parameter_table)
            info_parameter_fields = [info_parameter_table[f] for f in info_parameter_table.fields
                                     if f not in unwanted_fields]
            info_parameter_query_ = (info_parameter_table.alert_id == alert_id)
            for info_row in info_rows:
                info_id = info_row.id
                info_row_clone = info_row.as_dict()
                del info_row_clone["id"]
                if msg_type and msg_type == "AllClear":
                    info_row_clone["response_type"] = "AllClear"
                if record:
                    # Info History use-case
                    del info_row_clone["template_info_id"]
                    del info_row_clone["template_settings"]
                    del info_row_clone["event_type_id"]
                    info_row_clone["priority"] = info_table.priority.represent(info_row_clone["priority"])
                    info_row_clone["alert_history_id"] = new_alert_id
                    new_info_id = info_history_table.insert(**info_row_clone)
                    # Post-process create
                    info_row_clone["id"] = new_info_id
                    audit("create", "cap", "info_history", record=new_info_id)
                    set_record_owner(info_history_table, new_info_id)
                else:
                    # Change of msg_type use-case
                    info_row_clone["alert_id"] = new_alert_id
                    new_info_id = info_table.insert(**info_row_clone)
                    # Post-process create
                    info_row_clone["id"] = new_info_id
                    audit("create", "cap", "info", record=new_info_id)
                    set_record_owner(info_table, new_info_id)
                    onaccept(info_table, info_row_clone)

                # Copy the info parameters
                info_parameter_query = info_parameter_query_ & \
                                       (info_parameter_table.info_id == info_id) & \
                                       info_parameter_accessible
                info_parameter_rows = db(info_parameter_query).select(*info_parameter_fields)
                for info_parameter_row in info_parameter_rows:
                    info_parameter_row_clone = info_parameter_row.as_dict()
                    if record:
                        # History table use-case
                        info_parameter_row_clone["alert_history_id"] = new_alert_id
                        info_parameter_row_clone["info_history_id"] = new_info_id
                        new_info_parameter_id = info_parameter_history_table_insert(**info_parameter_row_clone)
                        # Post-process create
                        info_parameter_row_clone["id"] = new_info_parameter_id
                        audit("create", "cap", "info_parameter_history",
                              record=new_info_parameter_id)
                        set_record_owner(info_parameter_history_table, new_info_parameter_id)
                    else:
                        # Change of msg_type use-case
                        info_parameter_row_clone.update(alert_id = new_alert_id,
                                                        info_id = new_info_id)
                        new_info_parameter_id = info_parameter_table_insert(**info_parameter_row_clone)
                        # Post-process create
                        info_parameter_row_clone["id"] = new_info_parameter_id
                        audit("create", "cap", "info_parameter",
                              record=new_info_parameter_id)
                        set_record_owner(info_parameter_table, new_info_parameter_id)
                        onaccept(info_parameter_table, info_parameter_row_clone)

    if has_permission("create", area_table):
        # Copy the area segment
        area_fields = [area_table[f] for f in area_table.fields
                       if f not in unwanted_fields_]
        area_query = (area_table.alert_id == alert_id) & \
                     accessible_query("read", area_table)
        area_rows = db(area_query).select(*area_fields)
        if len(area_rows):
            gtable = s3db.gis_location
            area_history_table = s3db.cap_area_history
            location_history_table = s3db.cap_area_location_history
            tag_history_table = s3db.cap_area_tag_history
            onvalidation = s3db.onvalidation
            area_table_insert = area_table.insert

            location_table_insert = location_table.insert
            location_accessible = accessible_query("read", location_table)
            location_fields = [location_table[f] for f in location_table.fields
                               if f not in unwanted_fields]

            tag_table_insert = tag_table.insert
            tag_accessible = accessible_query("read", tag_table)
            tag_fields = [tag_table[f] for f in tag_table.fields
                          if f not in unwanted_fields]

            for area_row in area_rows:
                area_id = area_row.id
                area_row_clone = area_row.as_dict()
                del area_row_clone["id"]
                if record:
                    # History table use-case
                    del area_row_clone["template_area_id"]
                    del area_row_clone["event_type_id"]
                    #del area_row_clone["priority"]
                    area_row_clone["alert_history_id"] = new_alert_id
                    new_area_id = area_history_table.insert(**area_row_clone)
                    # Post-process create
                    area_row_clone["id"] = new_area_id
                    audit("create", "cap", "area_history", record=new_area_id)
                    set_record_owner(area_history_table, new_area_id)
                else:
                    # Update/Error/Relay/All Clear use-case
                    area_row_clone["alert_id"] = new_alert_id

                    new_area_id = area_table_insert(**area_row_clone)
                    # Post-process create
                    area_row_clone["id"] = new_area_id
                    audit("create", "cap", "area", record=new_area_id)
                    set_record_owner(area_table, new_area_id)
                    onaccept(area_table, area_row_clone)

                # Copy the area_location
                location_query = (location_table.area_id == area_id) &\
                                 location_accessible
                location_rows = db(location_query).\
                                    select(*location_fields)
                for location_row in location_rows:
                    location_row_clone = location_row.as_dict()
                    if record:
                        # History table use-case
                        del location_row_clone["area_id"]
                        location_row_clone["alert_history_id"] = new_alert_id
                        location_row_clone["area_history_id"] = new_area_id
                        grow = db(gtable.id == location_row_clone["location_id"]).\
                                select(gtable.wkt, limitby=(0, 1)).first()
                        if grow:
                            location_row_clone["location_wkt"] = grow.wkt
                        del location_row_clone["location_id"]
                        new_location_id = location_history_table.insert(**location_row_clone)
                        # Post-process create
                        location_row_clone["id"] = new_location_id
                        audit("create", "cap", "area_location_history",
                              record=new_location_id)
                        set_record_owner(location_history_table, new_location_id)
                    else:
                        # Update/Error/Relay/All Clear use-case
                        location_row_clone.update(alert_id = new_alert_id,
                                                  area_id = new_area_id)
                        onvalidation(gtable, location_row_clone)
                        new_location_id = location_table_insert(**location_row_clone)
                        # Post-process create
                        location_row_clone["id"] = new_location_id
                        audit("create", "cap", "area_location",
                              record=new_location_id)
                        set_record_owner(location_table, new_location_id)
                        onaccept(location_table, location_row_clone)

                # Copy the area_tag
                tag_query = (tag_table.area_id == area_id) &\
                            tag_accessible
                tag_rows = db(tag_query).select(*tag_fields)
                for tag_row in tag_rows:
                    tag_row_clone = tag_row.as_dict()
                    if record:
                        # History table use-case
                        del tag_row_clone["area_id"]
                        tag_row_clone["alert_history_id"] = new_alert_id
                        tag_row_clone["area_history_id"] = new_area_id

                        new_tag_id = tag_history_table.insert(**tag_row_clone)
                        # Post-process create
                        tag_row_clone["id"] = new_tag_id
                        audit("create", "cap", "area_tag_history", record=new_tag_id)
                        set_record_owner(tag_history_table, new_tag_id)
                    else:
                        # Update/Error/Relay/All Clear use-case
                        tag_row_clone.update(alert_id = new_alert_id,
                                             area_id = new_area_id)

                        new_tag_id = tag_table_insert(**tag_row_clone)
                        # Post-process create
                        tag_row_clone["id"] = new_tag_id
                        audit("create", "cap", "area_tag", record=new_tag_id)
                        set_record_owner(tag_table, new_tag_id)
                        # Don't do onaccept as geocodes may create locations, so duplicates
                        # as Locations are cloned anyway
                        #onaccept(tag_table, tag_row_clone)
    if has_permission("create", resource_table):
        # Copy the resource segment
        resource_fields = [resource_table[f] for f in resource_table.fields
                           if f not in unwanted_fields]
        resource_query = (resource_table.alert_id == alert_id) &\
                         accessible_query("read", resource_table)
        resource_rows = db(resource_query).select(*resource_fields)
        if len(resource_rows):
            resource_history_table = s3db.cap_resource_history
            resource_table_insert = resource_table.insert
            update_super = s3db.update_super
            for resource_row in resource_rows:
                resource_row_clone = resource_row.as_dict()
                mime_type = resource_row_clone["mime_type"]
                if record:
                    # History Table use-case
                    resource_row_clone["alert_history_id"] = new_alert_id
                    rid = resource_history_table.insert(**resource_row_clone)
                    resource_row_clone["id"] = rid
                    # Post-process create
                    audit("create", "cap", "resource_history", record=rid)
                    set_record_owner(resource_history_table, rid)
                elif mime_type and mime_type != "cap":
                    # Update/Error/Relay/All Clear use-case
                    resource_row_clone["alert_id"] = new_alert_id
                    rid = resource_table_insert(**resource_row_clone)
                    resource_row_clone["id"] = rid
                    # Post-process create
                    audit("create", "cap", "resource", record=rid)
                    update_super(resource_table, resource_row_clone)
                    set_record_owner(resource_table, rid)
                    onaccept(resource_table, resource_row_clone)


    if not record:
        output = current.xml.json_message(message=new_alert_id)
        current.response.headers["Content-Type"] = "application/json"
        return output
    return

# -----------------------------------------------------------------------------
class cap_AlertProfileWidget(object):
    """ Custom profile widget builder """

    def __init__(self, title, label=None, value=None):
        """
            TODO docstring
        """

        self.title = title
        self.label = label
        self.value = value

    # -------------------------------------------------------------------------
    def __call__(self, f):
        """
            Widget builder

            @param f: the calling function

            TODO: explain return value and use as decorator
        """

        def widget(r, **attr):
            components = f(r, **attr)
            components = [c for c in components if c is not None]
            title = self.title
            if title:
                label = self.label
                value = self.value
                T = current.T
                if label and value:
                    title_ = DIV(SPAN("%s " % T(title),
                                      _class="cap-value upper"
                                      ),
                                 SPAN("%s :: " % T(label),
                                      _class="cap-label upper"
                                      ),
                                 SPAN(value,
                                      _class="cap-strong"
                                      ),
                                 )
                else:
                    title_ = DIV(SPAN(T(title),
                                      _class="cap-value upper"),
                                 )

                header = TAG[""](title_,
                                 DIV(_class="underline"),
                                 )
                output = DIV(header, *components)
            else:
                output = DIV(components)
            return output

        return widget

    # -------------------------------------------------------------------------
    @staticmethod
    def component(label, value,
                  represent = None,
                  uppercase = False,
                  strong = False,
                  hide_empty = True,
                  headline = False,
                  resource_segment = False,
                  ):
        """
            Component builder
            @param label: name for the component label
            @param value: value for the component
            @param represent: representation used for the value
            @param uppercase: whether to display label in upper case
            @param strong: whether to display with strong color
            @param hide_empty: whether to hide empty records
            @param headline: is headline?
            @param resource_segment: belongs to resource segment?
        """

        if not value and hide_empty:
            return None
        else:
            if isinstance(value, list):
                nvalue = []
                for value_ in value:
                    if value_:
                        if resource_segment and represent:
                            nvalue.append(represent(value_))
                        elif not resource_segment:
                            if represent:
                                nvalue.append(s3_str(represent(value_)))
                            else:
                                nvalue.append(s3_str(value_))
                if not resource_segment:
                    if len(nvalue):
                        nvalue = ", ".join(nvalue)
                    else:
                        return None
            else:
                if represent:
                    nvalue = represent(value)
                else:
                    nvalue = value

            label_class = "cap-label"
            if uppercase:
                label_class = "%s upper" % label_class
            value_class = "cap-value"
            if strong:
                value_class = "cap-strong"
            elif headline:
                value_class = "%s cap-headline" % value_class

            output = DIV(SPAN("%s :: " % current.T(label), _class=label_class),
                         SPAN(nvalue, _class=value_class),
                         )

            return output

# END =========================================================================
