# Slixmpp: The Slick XMPP Library
# Copyright (C) 2011 Nathanael C. Fritz, Lance J.T. Stout
# This file is part of Slixmpp.
# See the file LICENSE for copying permission.
import logging

from slixmpp.stanza import Message
from slixmpp.xmlstream import register_stanza_plugin
from slixmpp.xmlstream.handler import Callback
from slixmpp.xmlstream.matcher import StanzaPath
from slixmpp.plugins import BasePlugin
from slixmpp.plugins.xep_0224 import stanza


log = logging.getLogger(__name__)


class XEP_0224(BasePlugin):

    """
    XEP-0224: Attention
    """

    name = 'xep_0224'
    description = 'XEP-0224: Attention'
    dependencies = {'xep_0030'}
    stanza = stanza

    def plugin_init(self):
        """Start the XEP-0224 plugin."""
        register_stanza_plugin(Message, stanza.Attention)

        self.xmpp.register_handler(
                Callback('Attention',
                    StanzaPath('message/attention'),
                    self._handle_attention))

    def plugin_end(self):
        self.xmpp['xep_0030'].del_feature(feature=stanza.Attention.namespace)
        self.xmpp.remove_handler('Attention')

    def session_bind(self, jid):
        self.xmpp['xep_0030'].add_feature(stanza.Attention.namespace)

    def request_attention(self, to, mfrom=None, mbody=''):
        """
        Send an attention message with an optional body.

        Arguments:
            to    -- The attention request recipient's JID.
            mfrom -- Optionally specify the sender of the attention request.
            mbody -- An optional message body to include in the request.
        """
        m = self.xmpp.Message()
        m['to'] = to
        m['type'] = 'headline'
        m['attention'] = True
        if mfrom:
            m['from'] = mfrom
        m['body'] = mbody
        m.send()

    def _handle_attention(self, msg):
        """
        Raise an event after receiving a message with an attention request.

        Arguments:
            msg -- A message stanza with an attention element.
        """
        log.debug("Received attention request from: %s", msg['from'])
        self.xmpp.event('attention', msg)