# Miro - an RSS based video player application
# Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011
# Participatory Culture Foundation
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
#
# In addition, as a special exception, the copyright holders give
# permission to link the code of portions of this program with the OpenSSL
# library.
#
# You must obey the GNU General Public License in all respects for all of
# the code used other than OpenSSL. If you modify file(s) with this
# exception, you may extend this exception to your version of the file(s),
# but you are not obligated to do so. If you do not wish to do so, delete
# this exception statement from your version. If you delete this exception
# statement from all source files in the program, then also delete it here.

"""miro.frontends.shell -- A quick shell for debugging Miro
innards.
"""

import readline
import rlcompleter
import code

from miro import app
from miro import startup
from miro import messages
from miro import signals

def run_application():
    app.info_updater = InfoUpdater()
    messages.FrontendMessage.install_handler(MessageHandler())
    startup.startup()
    print 'startup exit'

class MessageHandler(messages.MessageHandler):
    def handle(self, message):
        if isinstance(message, messages.StartupSuccess):
            self.run_shell()
        else:
            print 'got message: ', message

    def run_shell(self):
        print
        print '** starting shell**'
        print
        imported_objects = {}
        for mod in ('database', 'feed', 'item', 'models'):
            imported_objects[mod] = getattr(__import__('miro.%s' % mod), mod)
        readline.set_completer(
            rlcompleter.Completer(imported_objects).complete)
        readline.parse_and_bind("tab:complete")
        code.interact(local=imported_objects)

        app.controller.shutdown()

class InfoUpdaterCallbackList(object):
    """Tracks the list of callbacks for InfoUpdater.
    """

    def __init__(self):
        self._callbacks = {}

    def add(self, type_, id_, callback):
        """Adds the callback to the list for ``type_`` ``id_``.

        :param type_: the type of the thing (feed, site, ...)
        :param id_: the id for the thing
        :param callback: the callback function to add
        """
        key = (type_, id_)
        self._callbacks.setdefault(key, set()).add(callback)

    def remove(self, type_, id_, callback):
        """Removes the callback from the list for ``type_`` ``id_``.

        :param type_: the type of the thing (feed, site, ...)
        :param id_: the id for the thing
        :param callback: the callback function to remove
        """
        key = (type_, id_)
        callback_set = self._callbacks[key]
        callback_set.remove(callback)
        if len(callback_set) == 0:
            del self._callbacks[key]

    def get(self, type_, id_):
        """Get the list of callbacks for ``type_``, ``id_``.

        :param type_: the type of the thing (feed, site, ...)
        :param id_: the id for the thing
        """
        key = (type_, id_)
        if key not in self._callbacks:
            return []
        else:
            # return a new list of callbacks, so that if we iterate over the
            # return value, we don't have to worry about callbacks being
            # removed midway.
            return list(self._callbacks[key])

class InfoUpdater(signals.SignalEmitter):
    def __init__(self):
        signals.SignalEmitter.__init__(self)
        for prefix in ('feeds', 'sites', 'playlists'):
            self.create_signal('%s-added' % prefix)
            self.create_signal('%s-changed' % prefix)
            self.create_signal('%s-removed' % prefix)

        self.item_list_callbacks = InfoUpdaterCallbackList()
        self.item_changed_callbacks = InfoUpdaterCallbackList()

    def handle_items_changed(self, message):
        callback_list = self.item_changed_callbacks
        for callback in callback_list.get(message.type, message.id):
            callback(message)

    def handle_item_list(self, message):
        callback_list = self.item_list_callbacks
        for callback in callback_list.get(message.type, message.id):
            callback(message)

    def handle_tabs_changed(self, message):
        if message.type == 'feed':
            signal_start = 'feeds'
        elif message.type == 'site':
            signal_start = 'sites'
        elif message.type == 'playlist':
            signal_start = 'playlists'
        else:
            return
        if message.added:
            self.emit('%s-added' % signal_start, message.added)
        if message.changed:
            self.emit('%s-changed' % signal_start, message.changed)
        if message.removed:
            self.emit('%s-removed' % signal_start, message.removed)
