#!/usr/bin/python
# -*- coding: utf-8 -*-

# SAT plugin for managing xep-0184
# Copyright (C) 2009-2016 Geoffrey POUZET (chteufleur@kingpenguin.tk)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
from sat.core.i18n import _
from sat.core.log import getLogger
from twisted.internet import reactor
from twisted.words.protocols.jabber import xmlstream
from twisted.words.xish import domish
log = getLogger(__name__)

from wokkel import disco, iwokkel
from zope.interface import implements
try:
    from twisted.words.protocols.xmlstream import XMPPHandler
except ImportError:
    from wokkel.subprotocols import XMPPHandler


NS_MESSAGE_DELIVERY_RECEIPTS = 'urn:xmpp:receipts'

MSG = 'message'

MSG_CHAT = '/'+MSG+'[@type="chat"]'
MSG_CHAT_MESSAGE_DELIVERY_RECEIPTS_REQUEST  = MSG_CHAT+'/request[@xmlns="'+NS_MESSAGE_DELIVERY_RECEIPTS+'"]'
MSG_CHAT_MESSAGE_DELIVERY_RECEIPTS_RECEIVED = MSG_CHAT+'/received[@xmlns="'+NS_MESSAGE_DELIVERY_RECEIPTS+'"]'

MSG_NORMAL = '/'+MSG+'[@type="normal"]'
MSG_NORMAL_MESSAGE_DELIVERY_RECEIPTS_REQUEST  = MSG_NORMAL+'/request[@xmlns="'+NS_MESSAGE_DELIVERY_RECEIPTS+'"]'
MSG_NORMAL_MESSAGE_DELIVERY_RECEIPTS_RECEIVED = MSG_NORMAL+'/received[@xmlns="'+NS_MESSAGE_DELIVERY_RECEIPTS+'"]'


PARAM_KEY = "Privacy"
PARAM_NAME = "Enable message delivery receipts"
ENTITY_KEY = PARAM_KEY + "_" + PARAM_NAME


PLUGIN_INFO = {
"name": "XEP-0184 Plugin",
"import_name": "XEP-0184",
"type": "XEP",
"protocols": ["XEP-0184"],
"dependencies": [],
"main": "XEP_0184",
"handler": "yes",
"description": _("""Implementation of Message Delivery Receipts""")
}


STATUS_MESSAGE_DELIVERY_RECEIVED = "delivered"
TEMPO_DELETE_WAITING_ACK_S = 300 # 5 min


class XEP_0184(object):
    """
    Implementation for XEP 0184.
    """
    params = """
    <params>
    <individual>
    <category name="%(category_name)s" label="%(category_label)s">
        <param name="%(param_name)s" label="%(param_label)s" value="false" type="bool" security="0"/>
     </category>
    </individual>
    </params>
    """ % {
        'category_name': PARAM_KEY,
        'category_label': _(PARAM_KEY),
        'param_name': PARAM_NAME,
        'param_label': _('Enable message delivery receipts')
    }

    def __init__(self, host):
        log.info(_("Plugin XEP_0184 (message delivery receipts) initialization"))
        self.host = host
        self._dictRequest = dict()

        # parameter value is retrieved before each use
        host.memory.updateParams(self.params)

        host.trigger.add("messageSend", self.messageSendTrigger)
        host.bridge.addSignal("messageState", ".plugin", signature='sss')  # message_uid, status, profile

    def getHandler(self, profile):
        return XEP_0184_handler(self, profile)

    def messageSendTrigger(self, client, mess_data, pre_xml_treatments, post_xml_treatments):
        """Install SendMessage command hook """
        def treatment(mess_data):
            message = mess_data['xml']
            message_type = message.getAttribute("type")

            if self._isActif(client.profile) and (message_type == "chat" or message_type == "normal"):
                message.addElement('request', NS_MESSAGE_DELIVERY_RECEIPTS)
                uid = mess_data['uid']
                msg_id = message.getAttribute("id")
                self._dictRequest[msg_id] = uid
                reactor.callLater(TEMPO_DELETE_WAITING_ACK_S, self._clearDictRequest, msg_id)
                log.debug(_("[XEP-0184] Request acknowledgment for message id {}".format(msg_id)))

            return mess_data

        post_xml_treatments.addCallback(treatment)
        return True


    def onMessageDeliveryReceiptsRequest(self, msg_elt, client):
        """This method is called on message delivery receipts **request** (XEP-0184 #7)
        @param msg_elt: message element
        @param client: %(doc_client)s"""

        if self._isActif(client.profile):
            received_elt_ret = domish.Element((NS_MESSAGE_DELIVERY_RECEIPTS, 'received'))
            received_elt_ret["id"] = msg_elt["id"]

            msg_result_elt = xmlstream.toResponse(msg_elt, 'result')
            msg_result_elt.addChild(received_elt_ret)
            client.xmlstream.send(msg_result_elt)

    def onMessageDeliveryReceiptsReceived(self, msg_elt, client):
        """This method is called on message delivery receipts **received** (XEP-0184 #7)
        @param msg_elt: message element
        @param client: %(doc_client)s"""
        msg_elt.handled = True
        rcv_elt = msg_elt.elements(NS_MESSAGE_DELIVERY_RECEIPTS, 'received').next()
        msg_id = rcv_elt['id']

        try:
            uid = self._dictRequest[msg_id]
            del self._dictRequest[msg_id]
            self.host.bridge.messageState(uid, STATUS_MESSAGE_DELIVERY_RECEIVED, client.profile)
            log.debug(_("[XEP-0184] Receive acknowledgment for message id {}".format(msg_id)))
        except KeyError:
            pass

    def _clearDictRequest(self, msg_id):
        try:
            del self._dictRequest[msg_id]
            log.debug(_("[XEP-0184] Delete waiting acknowledgment for message id {}".format(msg_id)))
        except KeyError:
            pass

    def _isActif(self, profile):
        return self.host.memory.getParamA(PARAM_NAME, PARAM_KEY, profile_key=profile)

class XEP_0184_handler(XMPPHandler):
    implements(iwokkel.IDisco)

    def __init__(self, plugin_parent, profile):
        self.plugin_parent = plugin_parent
        self.host = plugin_parent.host
        self.profile = profile

    def connectionInitialized(self):
        self.xmlstream.addObserver(MSG_CHAT_MESSAGE_DELIVERY_RECEIPTS_REQUEST, self.plugin_parent.onMessageDeliveryReceiptsRequest, client=self.parent)
        self.xmlstream.addObserver(MSG_CHAT_MESSAGE_DELIVERY_RECEIPTS_RECEIVED, self.plugin_parent.onMessageDeliveryReceiptsReceived, client=self.parent)

        self.xmlstream.addObserver(MSG_NORMAL_MESSAGE_DELIVERY_RECEIPTS_REQUEST, self.plugin_parent.onMessageDeliveryReceiptsRequest, client=self.parent)
        self.xmlstream.addObserver(MSG_NORMAL_MESSAGE_DELIVERY_RECEIPTS_RECEIVED, self.plugin_parent.onMessageDeliveryReceiptsReceived, client=self.parent)

    def getDiscoInfo(self, requestor, target, nodeIdentifier=''):
        return [disco.DiscoFeature(NS_MESSAGE_DELIVERY_RECEIPTS)]

    def getDiscoItems(self, requestor, target, nodeIdentifier=''):
        return []