# -*- coding:utf-8 -*-
## This file is part of Gajim.
##
## Gajim 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 3 only.
##
## Gajim 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 Gajim. If not, see <http://www.gnu.org/licenses/>.
##


"""
Handles  Jingle File Transfer (XEP 0234)
"""

import gajim
import xmpp
from jingle_content import contents, JingleContent
from jingle_transport import JingleTransportICEUDP, JingleTransportSocks5
from common import helpers
from common.socks5 import Socks5Receiver, Socks5Sender
from common.connection_handlers_events import FileRequestReceivedEvent

import logging
log = logging.getLogger('gajim.c.jingle_ft')

STATE_NOT_STARTED = 0
STATE_INITIALIZED = 1
STATE_ACCEPTED = 2
STATE_TRANSPORT_INFO = 3
STATE_PROXY_ACTIVATED = 4
# We send the candidates and we are waiting for a reply
STATE_CAND_SENT_PENDING_REPLY = 5
# We received the candidates and we are waiting to reply
STATE_CAND_RECEIVED_PENDING_REPLY = 6
# We have sent and received the candidates
# This also includes any candidate-error received or sent
STATE_CAND_SENT_AND_RECEIVED = 7
# We are transfering the file
STATE_TRANSFERING = 8
STATE_TRANSPORT_REPLACE = 9


class JingleFileTransfer(JingleContent):
    def __init__(self, session, transport=None, file_props=None,
    use_security=False):
        JingleContent.__init__(self, session, transport)

        log.info("transport value: %s" % transport)

        # events we might be interested in
        self.callbacks['session-initiate'] += [self.__on_session_initiate]
        self.callbacks['content-add'] += [self.__on_session_initiate]
        self.callbacks['session-accept'] += [self.__on_session_accept]
        self.callbacks['session-terminate'] += [self.__on_session_terminate]
        self.callbacks['transport-accept'] += [self.__on_transport_accept]
        self.callbacks['transport-replace'] += [self.__on_transport_replace]
        self.callbacks['session-accept-sent'] += [self._listen_host]
        # fallback transport method
        self.callbacks['transport-reject'] += [self.__on_transport_reject]
        self.callbacks['transport-info'] += [self.__on_transport_info]
        self.callbacks['iq-result'] += [self.__on_iq_result]

        self.state = STATE_NOT_STARTED

        self.use_security = use_security

        self.file_props = file_props
        if file_props is None:
            self.weinitiate = False
        else:
            self.weinitiate = True

        if self.file_props is not None:
            self.file_props['sender'] = session.ourjid
            self.file_props['receiver'] = session.peerjid
            self.file_props['session-type'] = 'jingle'
            self.file_props['session-sid'] = session.sid
            self.file_props['transfered_size'] = []

        log.info("FT request: %s" % file_props)

        if transport is None:
            self.transport = JingleTransportSocks5()
        self.transport.set_connection(session.connection)
        self.transport.set_file_props(self.file_props)
        self.transport.set_our_jid(session.ourjid)
        log.info('ourjid: %s' % session.ourjid)

        if self.file_props is not None:
            self.file_props['sid'] = self.transport.sid

        self.session = session
        self.media = 'file'
        self.nominated_cand = {}

    def __on_session_initiate(self, stanza, content, error, action):
        gajim.nec.push_incoming_event(FileRequestReceivedEvent(None,
            conn=self.session.connection, stanza=stanza, jingle_content=content,
            FT_content=self))

    def __on_session_accept(self, stanza, content, error, action):
        log.info("__on_session_accept")
        con = self.session.connection
        security = content.getTag('security')
        if not security: # responder can not verify our fingerprint
            self.use_security = False


        if self.state == STATE_TRANSPORT_REPLACE:
            # We ack the session accept
            response = stanza.buildReply('result')
            con.connection.send(response)
            # We send the file
            con.files_props[self.file_props['sid']] = self.file_props
            fp = open(self.file_props['file-name'], 'r')
            con.OpenStream( self.transport.sid, self.session.peerjid,
                            fp,    blocksize=4096)
            raise xmpp.NodeProcessed

        self.file_props['streamhosts'] = self.transport.remote_candidates
        for host in self.file_props['streamhosts']:
                host['initiator'] = self.session.initiator
                host['target'] = self.session.responder
                host['sid'] = self.file_props['sid']

        response = stanza.buildReply('result')
        con.connection.send(response)

        if not gajim.socks5queue.get_file_props(
           self.session.connection.name, self.file_props['sid']):
            gajim.socks5queue.add_file_props(self.session.connection.name,
                                            self.file_props)
        fingerprint = None
        if self.use_security:
            fingerprint = 'client'
        gajim.socks5queue.connect_to_hosts(self.session.connection.name,
                       self.file_props['sid'], self.send_candidate_used,
                         self._on_connect_error, fingerprint=fingerprint,
                         receiving=False)

        raise xmpp.NodeProcessed

    def __on_session_terminate(self, stanza, content, error, action):
        log.info("__on_session_terminate")

    def __on_transport_accept(self, stanza, content, error, action):
        log.info("__on_transport_accept")

    def __on_transport_replace(self, stanza, content, error, action):
        log.info("__on_transport_replace")

    def __on_transport_reject(self, stanza, content, error, action):
        log.info("__on_transport_reject")

    def __on_transport_info(self, stanza, content, error, action):
        log.info("__on_transport_info")

        #if not self.weinitiate: # proxy activated from initiator
        #    return
        if content.getTag('transport').getTag('candidate-error'):
            self.nominated_cand['peer-cand'] = False
            if self.state == STATE_CAND_SENT_PENDING_REPLY:
                if not self.nominated_cand['our-cand'] and \
                   not self.nominated_cand['peer-cand']:
                    if not self.weinitiate:
                        return
                    self.session.transport_replace()
                else:
                    response = stanza.buildReply('result')
                    self.session.connection.connection.send(response)
                    self.start_transfer()
                    raise xmpp.NodeProcessed
            else:
                self.state = STATE_CAND_RECEIVED_PENDING_REPLY

            return

        if content.getTag('transport').getTag('activated'):
            self.state = STATE_TRANSFERING
            jid = gajim.get_jid_without_resource(self.session.ourjid)
            gajim.socks5queue.send_file(self.file_props,
                self.session.connection.name, 'client')
            return

        streamhost_cid = content.getTag('transport').getTag('candidate-used').\
            getAttr('cid')
        streamhost_used = None
        for cand in self.transport.candidates:
            if cand['candidate_id'] == streamhost_cid:
                streamhost_used = cand
                break
        if streamhost_used == None:
            log.info("unknow streamhost")
            return
        # We save the candidate nominated by peer
        self.nominated_cand['peer-cand'] = streamhost_used
        if self.state == STATE_CAND_SENT_PENDING_REPLY:
            response = stanza.buildReply('result')
            self.session.connection.connection.send(response)
            self.start_transfer()
            raise xmpp.NodeProcessed
        else:
            self.state = STATE_CAND_RECEIVED_PENDING_REPLY



    def __on_iq_result(self, stanza, content, error, action):
        log.info("__on_iq_result")

        if self.weinitiate and self.state == STATE_NOT_STARTED:
            self.state = STATE_INITIALIZED
            self.session.connection.files_props[self.file_props['sid']] = \
                self.file_props
            # Listen on configured port for file transfer
            self._listen_host()
        elif not self.weinitiate and self.state == STATE_NOT_STARTED:
            # session-accept iq-result
            if not self.negotiated:
                return
            self.state = STATE_ACCEPTED
            if not gajim.socks5queue.get_file_props(
            self.session.connection.name, self.file_props['sid']):
                gajim.socks5queue.add_file_props(self.session.connection.name,
                    self.file_props)
            fingerprint = None
            if self.use_security:
                fingerprint = 'client'
            gajim.socks5queue.connect_to_hosts(self.session.connection.name,
                self.file_props['sid'], self.send_candidate_used,
                self._on_connect_error, fingerprint=fingerprint)
        elif not self.weinitiate and self.state == STATE_ACCEPTED:
            # transport-info iq-result
            self.state = STATE_TRANSPORT_INFO
        elif self.weinitiate and self.state == STATE_INITIALIZED:
            # proxy activated
            self.state = STATE_PROXY_ACTIVATED
        elif self.state == STATE_CAND_SENT_AND_RECEIVED:
            if not self.nominated_cand['our-cand'] and \
            not self.nominated_cand['peer-cand']:
                if not self.weinitiate:
                    return
                self.session.transport_replace()
                return
            # initiate transfer
            self.start_transfer()

    def send_candidate_used(self, streamhost):
        """
        send candidate-used stanza
        """
        log.info('send_candidate_used')
        if streamhost is None:
            return

        self.nominated_cand['our-cand'] = streamhost
        if self.state == STATE_CAND_RECEIVED_PENDING_REPLY:
            self.state = STATE_CAND_SENT_AND_RECEIVED
        else:
            self.state = STATE_CAND_SENT_PENDING_REPLY

        content = xmpp.Node('content')
        content.setAttr('creator', 'initiator')
        content.setAttr('name', self.name)

        transport = xmpp.Node('transport')
        transport.setNamespace(xmpp.NS_JINGLE_BYTESTREAM)
        transport.setAttr('sid', self.transport.sid)

        candidateused = xmpp.Node('candidate-used')
        candidateused.setAttr('cid', streamhost['cid'])

        transport.addChild(node=candidateused)
        content.addChild(node=transport)

        self.session.send_transport_info(content)


    def _on_connect_error(self, sid):
        self.nominated_cand['our-cand'] = False
        self.send_error_candidate()

        if self.state == STATE_CAND_RECEIVED_PENDING_REPLY:
            self.state = STATE_CAND_SENT_AND_RECEIVED
        else:
            self.state = STATE_CAND_SENT_PENDING_REPLY


        log.info('connect error, sid=' + sid)

    def _fill_content(self, content):
        description_node = xmpp.simplexml.Node(
            tag=xmpp.NS_JINGLE_FILE_TRANSFER + ' description')

        sioffer = xmpp.simplexml.Node(tag='offer')
        file_tag = sioffer.setTag('file', namespace=xmpp.NS_FILE)
        file_tag.setAttr('name', self.file_props['name'])
        file_tag.setAttr('size', self.file_props['size'])
        desc = file_tag.setTag('desc')
        if 'desc' in self.file_props:
            desc.setData(self.file_props['desc'])

        description_node.addChild(node=sioffer)

        if self.use_security:
            security = xmpp.simplexml.Node(
                tag=xmpp.NS_JINGLE_XTLS + ' security')
            # TODO: add fingerprint element
            for m in ('x509', ): # supported authentication methods
                method = xmpp.simplexml.Node(tag='method')
                method.setAttr('name', m)
                security.addChild(node=method)
            content.addChild(node=security)

        content.addChild(node=description_node)

    def _store_socks5_sid(self, sid, hash_id):
        # callback from socsk5queue.start_listener
        self.file_props['hash'] = hash_id

    def _listen_host(self, stanza=None, content=None, error=None
                     , action=None):

        receiver = self.file_props['receiver']
        sender = self.file_props['sender']
        sha_str = helpers.get_auth_sha(self.file_props['sid'], sender,
                receiver)
        self.file_props['sha_str'] = sha_str

        port = gajim.config.get('file_transfers_port')

        fingerprint = None
        if self.use_security:
            fingerprint = 'server'

        if self.weinitiate:
            listener = gajim.socks5queue.start_listener(port, sha_str,
                    self._store_socks5_sid, self.file_props,
                    fingerprint=fingerprint, type='sender')
        else:
            listener = gajim.socks5queue.start_listener(port, sha_str,
                    self._store_socks5_sid, self.file_props,
                    fingerprint=fingerprint, type='receiver')

        if not listener:
        # send error message, notify the user
            return
    def isOurCandUsed(self):
        '''
        If this method returns true then the candidate we nominated will be
        used, if false, the candidate nominated by peer will be used
        '''

        if self.nominated_cand['peer-cand'] == False:
            return True
        if self.nominated_cand['our-cand'] == False:
            return False

        peer_pr = int(self.nominated_cand['peer-cand']['priority'])
        our_pr = int(self.nominated_cand['our-cand']['priority'])

        if peer_pr != our_pr:
            return our_pr > peer_pr
        else:
            return self.weinitiate


    def start_transfer(self):

        self.state = STATE_TRANSFERING
        
        # It tells wether we start the transfer as client or server
        type = None

        if self.isOurCandUsed():
            type = 'client'
            streamhost_used = self.nominated_cand['our-cand']
        else:
            type = 'server'
            streamhost_used = self.nominated_cand['peer-cand']
            
        if streamhost_used['type'] == 'proxy':
            self.file_props['is_a_proxy'] = True
            if self.weinitiate:
                self.file_props['proxy_sender'] = streamhost_used['initiator']
                self.file_props['proxy_receiver'] = streamhost_used['target']
            else:
                self.file_props['proxy_sender'] = streamhost_used['target']
                self.file_props['proxy_receiver'] = streamhost_used['initiator']

        if not self.weinitiate and streamhost_used['type'] == 'proxy':
            r = gajim.socks5queue.readers
            for reader in r:
                if r[reader].host == streamhost_used['host'] and \
                r[reader].connected:
                    return

        if self.weinitiate and streamhost_used['type'] == 'proxy':
            s = gajim.socks5queue.senders
            for sender in s:
                if s[sender].host == streamhost_used['host'] and \
                s[sender].connected:
                    return

        if streamhost_used['type'] == 'proxy': 
            self.file_props['streamhost-used'] = True
            streamhost_used['sid'] = self.file_props['sid']
            self.file_props['streamhosts'] = []
            self.file_props['streamhosts'].append(streamhost_used)
            self.file_props['proxyhosts'] = []
            self.file_props['proxyhosts'].append(streamhost_used)

            if self.weinitiate:
                gajim.socks5queue.idx += 1
                idx = gajim.socks5queue.idx
                sockobj = Socks5Sender(gajim.idlequeue, idx,
                                       gajim.socks5queue, 
                                       mode='client', 
                                       _sock=None,
                                       host=str(streamhost_used['host']), 
                                       port=int(streamhost_used['port']),
                                       fingerprint=None, 
                                       connected=False, 
                                       file_props=self.file_props)
            else:
                sockobj = Socks5Receiver(gajim.idlequeue, streamhost_used,
                    sid=self.file_props['sid'], mode='client',
                    file_props=self.file_props, fingerprint=None)
            sockobj.proxy = True
            sockobj.streamhost = streamhost_used             
            gajim.socks5queue.add_sockobj(self.session.connection.name, 
                                           sockobj, 'sender')
            streamhost_used['idx'] = sockobj.queue_idx
            # If we offered the nominated candidate used, we activate
            # the proxy
            if not self.isOurCandUsed():
                gajim.socks5queue.on_success[self.file_props['sid']] = \
                self.transport._on_proxy_auth_ok
            # TODO: add on failure
        else:
            jid = gajim.get_jid_without_resource(self.session.ourjid)
            gajim.socks5queue.send_file(self.file_props,
                self.session.connection.name, type)

def get_content(desc):
    return JingleFileTransfer

contents[xmpp.NS_JINGLE_FILE_TRANSFER] = get_content