# -*- coding: ISO-8859-15 -*-
# =============================================================================
# Copyright (c) 2004, 2006 Sean C. Gillies
# Copyright (c) 2007 STFC <http://www.stfc.ac.uk>
#
# Authors : 
#          Dominic Lowe <d.lowe@rl.ac.uk>
#
# Contact email: d.lowe@rl.ac.uk
# =============================================================================

##########NOTE: Does not conform to new interfaces yet #################

from wcsBase import WCSBase, WCSCapabilitiesReader
from owslib.util import openURL, testXMLValue
from urllib import urlencode
from urllib2 import urlopen
from owslib.etree import etree
import os, errno
from owslib.coverage import wcsdecoder

def ns(tag):
    return '{http://www.opengis.net/wcs/1.1}'+tag

class ServiceException(Exception):
    pass

class WebCoverageService_1_1_0(WCSBase):
    """Abstraction for OGC Web Coverage Service (WCS), version 1.1.0
    Implements IWebCoverageService.
    """
    
    def __getitem__(self, name):
        ''' check contents dictionary to allow dict like access to service layers'''
        if name in self.__getattribute__('contents').keys():
            return self.__getattribute__('contents')[name]
        else:
            raise KeyError, "No content named %s" % name
    
    def __init__(self,url,xml, cookies):
        self.version='1.1.0'
        self.url = url   
        self.cookies=cookies
        # initialize from saved capability document or access the server
        reader = WCSCapabilitiesReader(self.version)
        if xml:
            self._capabilities = reader.readString(xml)
        else:
            self._capabilities = reader.read(self.url)
            
        #build metadata objects:
        
        #serviceIdentification metadata
        elem=self._capabilities.find('{http://www.opengis.net/wcs/1.1/ows}ServiceIdentification')
        self.identification=ServiceIdentification(elem)
        
        #serviceProvider
        elem=self._capabilities.find('{http://www.opengis.net/ows}ServiceProvider')
        self.provider=ServiceProvider(elem)
                
        #serviceOperations
        self.operations = []
        for elem in self._capabilities.findall('{http://www.opengis.net/wcs/1.1/ows}OperationsMetadata/{http://www.opengis.net/wcs/1.1/ows}Operation/'):
            self.operations.append(Operation(elem))
        
        # exceptions - ***********TO DO *************
            self.exceptions = [f.text for f \
                in self._capabilities.findall('Capability/Exception/Format')]
              
        # serviceContents: our assumption is that services use a top-level layer
        # as a metadata organizer, nothing more.
        self.contents = {}
        top = self._capabilities.find('{http://www.opengis.net/wcs/1.1}Contents/{http://www.opengis.net/wcs/1.1}CoverageSummary')
        for elem in self._capabilities.findall('{http://www.opengis.net/wcs/1.1}Contents/{http://www.opengis.net/wcs/1.1}CoverageSummary/{http://www.opengis.net/wcs/1.1}CoverageSummary'):                    
            cm=ContentMetadata(elem, top, self)
            self.contents[cm.id]=cm
            
        if self.contents=={}:
            #non-hierarchical.
            top=None
            for elem in self._capabilities.findall('{http://www.opengis.net/wcs/1.1}Contents/{http://www.opengis.net/wcs/1.1}CoverageSummary'):     
                cm=ContentMetadata(elem, top, self)
                #make the describeCoverage requests to populate the supported formats/crs attributes
                self.contents[cm.id]=cm

    def items(self):
        '''supports dict-like items() access'''
        items=[]
        for item in self.contents:
            items.append((item,self.contents[item]))
        return items
          
    #TO DECIDE: Offer repackaging of coverageXML/Multipart MIME output?
    #def getData(self, directory='outputdir', outputfile='coverage.nc',  **kwargs):
        #u=self.getCoverageRequest(**kwargs)
        ##create the directory if it doesn't exist:
        #try:
            #os.mkdir(directory)
        #except OSError, e:
            ## Ignore directory exists error
            #if e.errno <> errno.EEXIST:
                #raise          
        ##elif wcs.version=='1.1.0':
        ##Could be multipart mime or XML Coverages document, need to use the decoder...
        #decoder=wcsdecoder.WCSDecoder(u)
        #x=decoder.getCoverages()
        #if type(x) is wcsdecoder.MpartMime:
            #filenames=x.unpackToDir(directory)
            ##print 'Files from 1.1.0 service written to %s directory'%(directory)
        #else:
            #filenames=x
        #return filenames
    
    #TO DO: Handle rest of the  WCS 1.1.0 keyword parameters e.g. GridCRS etc. 
    def getCoverage(self, identifier=None, bbox=None, time=None, format = None, store=False, rangesubset=None, gridbaseCRS=None, gridtype=None, gridCS=None, gridorigin=None, gridoffsets=None, method='Get',**kwargs):
        """Request and return a coverage from the WCS as a file-like object
        note: additional **kwargs helps with multi-version implementation
        core keyword arguments should be supported cross version
        example:
        cvg=wcs.getCoverageRequest(identifier=['TuMYrRQ4'], timeSequence=['2792-06-01T00:00:00.0'], bbox=(-112,36,-106,41),format='application/netcdf', store='true')

        is equivalent to:
        http://myhost/mywcs?SERVICE=WCS&REQUEST=GetCoverage&IDENTIFIER=TuMYrRQ4&VERSION=1.1.0&BOUNDINGBOX=-180,-90,180,90&TIMESEQUENCE=[bb&FORMAT=application/netcdf
        
        if store = true, returns a coverages XML file
        if store = false, returns a multipart mime
        """
        self.log.debug('WCS 1.1.0 DEBUG: Parameters passed to GetCoverage: identifier=%s, bbox=%s, time=%s, format=%s,        rangesubset=%s, gridbaseCRS=%s, gridtype=%s, gridCS=%s, gridorigin=%s, gridoffsets=%s, method=%s, other_arguments=%s'%(identifier, bbox, time, format, rangesubset, gridbaseCRS, gridtype, gridCS, gridorigin, gridoffsets, method, str(kwargs)))
        
        
        if method == 'Get':
            method='{http://www.opengis.net/wcs/1.1/ows}Get'
        base_url = self.getOperationByName('GetCoverage').methods[method]['url']


        #process kwargs
        request = {'version': self.version, 'request': 'GetCoverage', 'service':'WCS'}
        assert len(identifier) > 0
        request['identifier']=identifier
        #request['identifier'] = ','.join(identifier)
        if bbox:
            request['boundingbox']=','.join([repr(x) for x in bbox])
        if time:
            request['timesequence']=','.join(time)
        request['format']=format
        request['store']=store
        
        #rangesubset: untested - require a server implementation
        if rangesubset:
            request['RangeSubset']=rangesubset
        
        #GridCRS structure: untested - require a server implementation
        if gridbaseCRS:
            request['gridbaseCRS']=gridbaseCRS
        if gridtype:
            request['gridtype']=gridtype
        if gridCS:
            request['gridCS']=gridCS
        if gridorigin:
            request['gridorigin']=gridorigin
        if gridoffsets:
            request['gridoffsets']=gridoffsets
       
       #anything else e.g. vendor specific parameters must go through kwargs
        if kwargs:
            for kw in kwargs:
                request[kw]=kwargs[kw]
        
        #encode and request
        data = urlencode(request)
        
        u=openURL(base_url, data, method, self.cookies)
        return u
        
        
    def getOperationByName(self, name):
        """Return a named operation item."""
        for item in self.operations:
            if item.name == name:
                return item
        raise KeyError, "No operation named %s" % name
        
class Operation(object):
    """Abstraction for operation metadata    
    Implements IOperationMetadata.
    """
    def __init__(self, elem):
        self.name = elem.get('name')       
        self.formatOptions = [f.text for f in elem.findall('{http://www.opengis.net/wcs/1.1/ows}Parameter/{http://www.opengis.net/wcs/1.1/ows}AllowedValues/{http://www.opengis.net/wcs/1.1/ows}Value')]
        methods = []
        for verb in elem.findall('{http://www.opengis.net/wcs/1.1/ows}DCP/{http://www.opengis.net/wcs/1.1/ows}HTTP/*'):
            url = verb.attrib['{http://www.w3.org/1999/xlink}href']
            methods.append((verb.tag, {'url': url}))
        self.methods = dict(methods)

class ServiceIdentification(object):
    """ Abstraction for ServiceIdentification Metadata 
    implements IServiceIdentificationMetadata"""
    def __init__(self,elem):        
        self.service="WCS"
        self.version="1.1.0"
        self.title=testXMLValue(elem.find('{http://www.opengis.net/ows}Title'))
        if self.title is None:  #may have used the wcs ows namespace:
            self.title=testXMLValue(elem.find('{http://www.opengis.net/wcs/1.1/ows}Title'))
        
        self.abstract=testXMLValue(elem.find('{http://www.opengis.net/ows}Abstract'))
        if self.abstract is None:#may have used the wcs ows namespace:
            self.abstract=testXMLValue(elem.find('{http://www.opengis.net/wcs/1.1/ows}Abstract'))
        if elem.find('{http://www.opengis.net/ows}Abstract') is not None:
            self.abstract=elem.find('{http://www.opengis.net/ows}Abstract').text
        else:
            self.abstract = None
        self.keywords = [f.text for f in elem.findall('{http://www.opengis.net/ows}Keywords/{http://www.opengis.net/ows}Keyword')]
        #self.link = elem.find('{http://www.opengis.net/wcs/1.1}Service/{http://www.opengis.net/wcs/1.1}OnlineResource').attrib.get('{http://www.w3.org/1999/xlink}href', '')
               
        if elem.find('{http://www.opengis.net/wcs/1.1/ows}Fees') is not None:            
            self.fees=elem.find('{http://www.opengis.net/wcs/1.1/ows}Fees').text
        else:
            self.fees=None
        
        if  elem.find('{http://www.opengis.net/wcs/1.1/ows}AccessConstraints') is not None:
            self.accessConstraints=elem.find('{http://www.opengis.net/wcs/1.1/ows}AccessConstraints').text
        else:
            self.accessConstraints=None
       
       
class ServiceProvider(object):
    """ Abstraction for ServiceProvider metadata 
    implements IServiceProviderMetadata """
    def __init__(self,elem):
        name=elem.find('{http://www.opengis.net/ows}ProviderName')
        if name is not None:
            self.name=name.text
        else:
            self.name=None
        #self.contact=ServiceContact(elem.find('{http://www.opengis.net/ows}ServiceContact'))
        self.contact =ContactMetadata(elem)
        self.url=self.name # no obvious definitive place for url in wcs, repeat provider name?

class ContactMetadata(object):
    ''' implements IContactMetadata'''
    def __init__(self, elem):
        try:
            self.name = elem.find('{http://www.opengis.net/ows}ServiceContact/{http://www.opengis.net/ows}IndividualName').text
        except AttributeError:
            self.name = None
        
        try:
            self.organization=elem.find('{http://www.opengis.net/ows}ProviderName').text 
        except AttributeError:
            self.organization = None
        
        try:
            self.address = elem.find('{http://www.opengis.net/ows}ServiceContact/{http://www.opengis.net/ows}ContactInfo/{http://www.opengis.net/ows}Address/{http://www.opengis.net/ows}DeliveryPoint').text
        except AttributeError:
            self.address = None
        try:
            self.city=  elem.find('{http://www.opengis.net/ows}ServiceContact/{http://www.opengis.net/ows}ContactInfo/{http://www.opengis.net/ows}Address/{http://www.opengis.net/ows}City').text
        except AttributeError:
            self.city = None
        
        try:
            self.region= elem.find('{http://www.opengis.net/ows}ServiceContact/{http://www.opengis.net/ows}ContactInfo/{http://www.opengis.net/ows}Address/{http://www.opengis.net/ows}AdministrativeArea').text
        except AttributeError:
            self.region = None
        
        try:
            self.postcode= elem.find('{http://www.opengis.net/ows}ServiceContact/{http://www.opengis.net/ows}ContactInfo/{http://www.opengis.net/ows}Address/{http://www.opengis.net/ows}PostalCode').text
        except AttributeError:
            self.postcode = None
        
        try:
            self.country= elem.find('{http://www.opengis.net/ows}ServiceContact/{http://www.opengis.net/ows}ContactInfo/{http://www.opengis.net/ows}Address/{http://www.opengis.net/ows}Country').text
        except AttributeError:
            self.country = None
        
        try:
            self.email =            elem.find('{http://www.opengis.net/ows}ServiceContact/{http://www.opengis.net/ows}ContactInfo/{http://www.opengis.net/ows}Address/{http://www.opengis.net/ows}ElectronicMailAddress').text
        except AttributeError:
            self.email = None

class ContentMetadata(object):
    """Abstraction for WCS ContentMetadata
    Implements IContentMetadata
    """
    def __init__(self, elem, parent, service):
        """Initialize."""
        #TODO - examine the parent for bounding box info.
        
        self._service=service
        self._elem=elem
        self._parent=parent
        self.id=self._checkChildAndParent('{http://www.opengis.net/wcs/1.1}Identifier')
        self.description =self._checkChildAndParent('{http://www.opengis.net/wcs/1.1}Description')           
        self.title =self._checkChildAndParent('{http://www.opengis.net/ows}Title')
        self.abstract =self._checkChildAndParent('{http://www.opengis.net/ows}Abstract')
        
        #keywords.
        self.keywords=[]
        for kw in elem.findall('{http://www.opengis.net/ows}Keywords/{http://www.opengis.net/ows}Keyword'):
            if kw is not None:
                self.keywords.append(kw.text)
        
        #also inherit any keywords from parent coverage summary (if there is one)
        if parent is not None:
            for kw in parent.findall('{http://www.opengis.net/ows}Keywords/{http://www.opengis.net/ows}Keyword'):
                if kw is not None:
                    self.keywords.append(kw.text)
            
        self.boundingBox=None #needed for iContentMetadata harmonisation
        self.boundingBoxWGS84 = None
        b = elem.find('{http://www.opengis.net/ows}WGS84BoundingBox')
        if b is not None:
            lc=b.find('{http://www.opengis.net/ows}LowerCorner').text
            uc=b.find('{http://www.opengis.net/ows}UpperCorner').text
            self.boundingBoxWGS84 = (
                    float(lc.split()[0]),float(lc.split()[1]),
                    float(uc.split()[0]), float(uc.split()[1]),
                    )
                
        # bboxes - other CRS 
        self.boundingboxes = []
        for bbox in elem.findall('{http://www.opengis.net/ows}BoundingBox'):
            if bbox is not None:
                try:
                    lc=b.find('{http://www.opengis.net/ows}LowerCorner').text
                    uc=b.find('{http://www.opengis.net/ows}UpperCorner').text
                    boundingBox =  (
                            float(lc.split()[0]),float(lc.split()[1]),
                            float(uc.split()[0]), float(uc.split()[1]),
                            b.attrib['crs'])
                    self.boundingboxes.append(boundingBox)
                except:
                     pass

        #others not used but needed for iContentMetadata harmonisation
        self.styles=None
        self.crsOptions=None
                
        #SupportedCRS
        self.supportedCRS=[]
        for crs in elem.findall('{http://www.opengis.net/wcs/1.1}SupportedCRS'):
            self.supportedCRS.append(crs.text)
            
            
        #SupportedFormats         
        self.supportedFormats=[]
        for format in elem.findall('{http://www.opengis.net/wcs/1.1}SupportedFormat'):
            self.supportedFormats.append(format.text)
            
    #grid is either a gml:Grid or a gml:RectifiedGrid if supplied as part of the DescribeCoverage response.
    def _getGrid(self):
        grid=None
        #TODO- convert this to 1.1 from 1.0
        #if not hasattr(self, 'descCov'):
                #self.descCov=self._service.getDescribeCoverage(self.id)
        #gridelem= self.descCov.find(ns('CoverageOffering/')+ns('domainSet/')+ns('spatialDomain/')+'{http://www.opengis.net/gml}RectifiedGrid')
        #if gridelem is not None:
            #grid=RectifiedGrid(gridelem)
        #else:
            #gridelem=self.descCov.find(ns('CoverageOffering/')+ns('domainSet/')+ns('spatialDomain/')+'{http://www.opengis.net/gml}Grid')
            #grid=Grid(gridelem)
        return grid
    grid=property(_getGrid, None)
        
        
        
    #time limits/postions require a describeCoverage request therefore only resolve when requested
    def _getTimeLimits(self):
         timelimits=[]
         for elem in self._service.getDescribeCoverage(self.id).findall(ns('CoverageDescription/')+ns('Domain/')+ns('TemporalDomain/')+ns('TimePeriod/')):
             subelems=elem.getchildren()
             timelimits=[subelems[0].text,subelems[1].text]
         return timelimits
    timelimits=property(_getTimeLimits, None)
    
    #TODO timepositions property
    def _getTimePositions(self):
        return []
    timepositions=property(_getTimePositions, None)
    
    def _checkChildAndParent(self, path):
        ''' checks child coverage  summary, and if item not found checks higher level coverage summary'''
        try:
            value = self._elem.find(path).text
        except:
            try:
                value = self._parent.find(path).text
            except:
                value = None
        return value  
