# -*- coding: utf-8 -*-
"""
OpenLP - Open Source Lyrics Projection

Copyright (c) 2008 Raoul Snyman

Portions copyright (c) 2008-2009 Martin Thompson, Tim Bentley,

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; version 2 of the License.

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., 59 Temple
Place, Suite 330, Boston, MA 02111-1307 USA
"""
import logging

from PyQt4 import QtCore

class EventReceiver(QtCore.QObject):
    """
    Class to allow events to be passed from different parts of the system.
    This is a private class and should not be used directly but via the Receiver class

    ``stop_import``
        Stops the Bible Import
    ``pre_load_bibles``
        Triggers the plugin to relaod the bible lists
    ``process_events``
        Requests the Application to flush the events queue
    ``{preview|live}_slide_first``
        display the first slide on the list
    ``{preview|live}_slide_previous``
        display the previous slide on the list
    ``{preview|live}_slide_next``
        display the next slide on the list
    ``{preview|live}_slide_last``
        display the last slide on the list
    ``{plugin}_add_service_item ``
        ask the plugin to push the selected items to the service item
    ``update_themes ``
        send out message with new themes
    ``update_global_theme ``
        Tell the components we have a new global theme
    ``load_song_list``
        Tells the the song plugin to reload the song list

    """
    global log
    log = logging.getLogger(u'EventReceiver')

    def __init__(self):
        QtCore.QObject.__init__(self)

    def send_message(self, event, msg=None):
        log.debug(u'Event %s passed with payload %s' % (event, msg))
        self.emit(QtCore.SIGNAL(event), msg)

class Receiver():
    """
    Class to allow events to be passed from different parts of the system.
    This is a static wrapper around the EventReceiver class.
    As there is only one instance of it in the systems the QT signal/slot architecture
    can send messages across the system

    ``Send message``
       Receiver().send_message(u'<<Message ID>>', data)

    ``Receive Message``
        QtCore.QObject.connect(Receiver().get_receiver(),QtCore.SIGNAL(u'<<Message ID>>'),<<ACTION>>)
    """
    eventreceiver = EventReceiver()

    @staticmethod
    def send_message(event, msg=None):
        Receiver.eventreceiver.send_message(event, msg)

    @staticmethod
    def get_receiver():
        return Receiver.eventreceiver