"""
The B{0install add-feed} command-line interface.
"""

# Copyright (C) 2011, Thomas Leonard
# See the README file for details, or visit http://0install.net.

from __future__ import print_function

from zeroinstall import SafeException, _
from zeroinstall.support import tasks
from zeroinstall.cmd import UsageError
from zeroinstall.injector import model, writer

syntax = "[INTERFACE] NEW-FEED"

def add_options(parser):
	parser.add_option("-o", "--offline", help=_("try to avoid using the network"), action='store_true')

def find_feed_import(iface, feed_url):
	for f in iface.extra_feeds:
		if f.uri == feed_url:
			return f
	return None

def handle(config, options, args, add_ok = True, remove_ok = False):
	if len(args) == 2:
		iface = config.iface_cache.get_interface(model.canonical_iface_uri(args[0]))
		feed_url = model.canonical_iface_uri(args[1])

		feed_import = find_feed_import(iface, feed_url)
		if feed_import:
			raise SafeException(_('Interface %(interface)s already has a feed %(feed)s') %
						{'interface': iface.uri, 'feed': feed_url})
		iface.extra_feeds.append(model.Feed(feed_url, arch = None, user_override = True))
		writer.save_interface(iface)
		return
	elif len(args) != 1: raise UsageError()

	x = args[0]

	print(_("Feed '%s':") % x + '\n')
	x = model.canonical_iface_uri(x)
	if options.offline:
		config.network_use = model.network_offline

	if config.network_use != model.network_offline and config.iface_cache.is_stale(x, config.freshness):
		blocker = config.fetcher.download_and_import_feed(x, config.iface_cache)
		print(_("Downloading feed; please wait..."))
		tasks.wait_for_blocker(blocker)
		print(_("Done"))

	candidate_interfaces = config.iface_cache.get_feed_targets(x)
	assert candidate_interfaces
	interfaces = []
	for i in range(len(candidate_interfaces)):
		iface = candidate_interfaces[i]
		if find_feed_import(iface, x):
			if remove_ok:
				print(_("%(index)d) Remove as feed for '%(uri)s'") % {'index': i + 1, 'uri': iface.uri})
				interfaces.append(iface)
		else:
			if add_ok:
				print(_("%(index)d) Add as feed for '%(uri)s'") % {'index': i + 1, 'uri': iface.uri})
				interfaces.append(iface)
	if not interfaces:
		if remove_ok:
			raise SafeException(_("%(feed)s is not registered as a feed for %(interface)s") %
						{'feed': x, 'interface': candidate_interfaces[0]})
		else:
			raise SafeException(_("%(feed)s already registered as a feed for %(interface)s") %
						{'feed': x, 'interface': candidate_interfaces[0]})
	print()
	while True:
		try:
			i = raw_input(_('Enter a number, or CTRL-C to cancel [1]: ')).strip()
		except KeyboardInterrupt:
			print()
			raise SafeException(_("Aborted at user request."))
		if i == '':
			i = 1
		else:
			try:
				i = int(i)
			except ValueError:
				i = 0
		if i > 0 and i <= len(interfaces):
			break
		print(_("Invalid number. Try again. (1 to %d)") % len(interfaces))
	iface = interfaces[i - 1]
	feed_import = find_feed_import(iface, x)
	if feed_import:
		iface.extra_feeds.remove(feed_import)
	else:
		iface.extra_feeds.append(model.Feed(x, arch = None, user_override = True))
	writer.save_interface(iface)
	print('\n' + _("Feed list for interface '%s' is now:") % iface.get_name())
	if iface.extra_feeds:
		for f in iface.extra_feeds:
			print("- " + f.uri)
	else:
		print(_("(no feeds)"))
