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

# SAT plugin for Jingle File Transfer (XEP-0234)
# Copyright (C) 2009, 2010, 2011, 2012, 2013, 2014, 2015 Jérôme Poisson (goffi@goffi.org)

# 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 _, D_
from sat.core.constants import Const as C
from sat.core.log import getLogger
log = getLogger(__name__)
from sat.core import exceptions
from sat.tools import xml_tools
from wokkel import disco, iwokkel
from zope.interface import implements
from sat.tools import utils
import os.path
from twisted.words.xish import domish
from twisted.words.protocols.jabber import jid
from twisted.python import failure

try:
    from twisted.words.protocols.xmlstream import XMPPHandler
except ImportError:
    from wokkel.subprotocols import XMPPHandler


NS_JINGLE_FT = 'urn:xmpp:jingle:apps:file-transfer:4'
CONFIRM = D_(u'{entity} wants to send the file "{name}" to you:\n{desc}\n\nThe file has a size of {size_human}\n\nDo you accept ?')
CONFIRM_TITLE = D_(u'Confirm file transfer')
CONFIRM_OVERWRITE = D_(u'File {} already exists, are you sure you want to overwrite ?')
CONFIRM_OVERWRITE_TITLE = D_(u'File exists')

PLUGIN_INFO = {
    "name": "Jingle File Transfer",
    "import_name": "XEP-0234",
    "type": "XEP",
    "protocols": ["XEP-0234"],
    "dependencies": ["XEP-0166", "XEP-0300", "FILE"],
    "main": "XEP_0234",
    "handler": "yes",
    "description": _("""Implementation of Jingle File Transfer""")
}


class XEP_0234(object):

    def __init__(self, host):
        log.info(_("plugin Jingle File Transfer initialization"))
        self.host = host
        self._j = host.plugins["XEP-0166"] # shortcut to access jingle
        self._j.registerApplication(NS_JINGLE_FT, self)
        self._f = host.plugins["FILE"]
        host.bridge.addMethod("fileJingleSend", ".plugin", in_sign='sssss', out_sign='', method=self._fileJingleSend)

    def getHandler(self, profile):
        return XEP_0234_handler()

    def _fileJingleSend(self, to_jid, filepath, name="", file_desc="", profile=C.PROF_KEY_NONE):
        return self.fileJingleSend(jid.JID(to_jid), filepath, name or None, file_desc or None, profile)

    def fileJingleSend(self, to_jid, filepath, name=None, file_desc=None, profile=C.PROF_KEY_NONE):
        self._j.initiate(to_jid,
                         [{'app_ns': NS_JINGLE_FT,
                           'app_kwargs': {'filepath': filepath,
                                          'name': name,
                                          'file_desc': file_desc},
                         }],
                         profile=profile)


    # Dialogs with user
    # the overwrite check is done here

    def _getDestDir(self, session, content_data, profile):
        """Request confirmation and destination dir to user

        if transfer is confirmed, session is filled
        @param session(dict): jingle session data
        @param content_data(dict): content informations
        @param profile: %(doc_profile)s
        return (defer.Deferred): True if transfer is accepted
        """
        file_data = content_data['file_data']
        d = xml_tools.deferDialog(self.host,
            _(CONFIRM).format(entity=session['to_jid'].full(), **file_data),
            _(CONFIRM_TITLE),
            type_=C.XMLUI_DIALOG_FILE,
            options={C.XMLUI_DATA_FILETYPE: C.XMLUI_DATA_FILETYPE_DIR},
            profile=profile)
        d.addCallback(self._gotConfirmation, session, content_data, profile)
        return d

    def _gotConfirmation(self, data, session, content_data, profile):
        """Called when the permission and dest path have been received

        @param data(dict): xmlui data received from file dialog
        return (bool): True if copy is wanted and OK
            False if user wants to cancel
            if fill exists ask confirmation and call again self._getDestDir if needed
        """
        if data.get('cancelled', False):
            return False
        file_data = content_data['file_data']
        path = data['path']
        file_data['file_path'] = file_path = os.path.join(path, file_data['name'])
        log.debug(u'destination file path set to {}'.format(file_path))

        # we manage case where file already exists
        if os.path.exists(file_path):
            def check_overwrite(overwrite):
                if overwrite:
                    assert 'file_obj' not in content_data
                    content_data['file_obj'] = open(file_path, 'w')
                    return True
                else:
                    return self._getDestDir(session, content_data, profile)

            exists_d = xml_tools.deferConfirm(
                self.host,
                _(CONFIRM_OVERWRITE).format(file_path),
                _(CONFIRM_OVERWRITE_TITLE),
                profile=profile)
            exists_d.addCallback(check_overwrite)
            return exists_d

        assert 'file_obj' not in content_data
        content_data['file_obj'] = open(file_path, 'w')
        return True

    # jingle callbacks

    def jingleSessionInit(self, session, content_name, filepath, name=None, file_desc=None, profile=C.PROF_KEY_NONE):
        content_data = session['contents'][content_name]
        assert 'file_path' not in content_data
        content_data['file_path'] = filepath
        file_data = content_data['file_data'] = {}
        file_data['date'] = utils.xmpp_date()
        file_data['desc'] = file_desc or ''
        file_data['media-type'] = "application/octet-stream" # TODO
        file_data['name'] = os.path.basename(filepath) if name is None else name
        file_data['size'] = os.path.getsize(filepath)
        desc_elt = domish.Element((NS_JINGLE_FT, 'description'))
        file_elt = desc_elt.addElement("file")
        for name in ('date', 'desc', 'media-type', 'name', 'size'):
            file_elt.addElement(name, content=unicode(file_data[name]))
        file_elt.addElement("range") # TODO
        file_elt.addChild(self.host.plugins["XEP-0300"].buidHash())
        return desc_elt

    def jingleRequestConfirmation(self, action, session, content_name, desc_elt, profile):
        """This method request confirmation for a jingle session"""
        content_data = session['contents'][content_name]
        # first we grab file informations
        try:
            file_elt = desc_elt.elements(NS_JINGLE_FT, 'file').next()
        except StopIteration:
            raise failure.Failure(exceptions.DataError)
        file_data = {}
        for name in ('date', 'desc', 'media-type', 'name', 'range', 'size'):
            try:
                file_data[name] = unicode(file_elt.elements(NS_JINGLE_FT, name).next())
            except StopIteration:
                file_data[name] = ''

        try:
            size = file_data['size'] = int(file_data['size'])
        except ValueError:
            raise failure.Failure(exceptions.DataError)
        else:
            # human readable size
            file_data['size_human'] = u'{:.6n} Mio'.format(float(size)/(1024**2))

        name = file_data['name']
        if '/' in name or '\\' in name:
            log.warning(u"File name contain path characters, we replace them: {}".format(name))
            file_data['name'] = name.replace('/', '_').replace('\\', '_')

        # TODO: parse hash using plugin XEP-0300

        content_data['file_data'] = file_data

        # now we actualy request permission to user
        return self._getDestDir(session, content_data, profile)


    def jingleHandler(self, action, session, content_name, desc_elt, profile):
        content_data = session['contents'][content_name]
        if action in (self._j.A_SESSION_INITIATE, self._j.A_ACCEPTED_ACK):
            pass
        elif action == self._j.A_SESSION_ACCEPT:
            assert not 'file_obj' in content_data
            file_path = content_data['file_path']
            size = content_data['file_data']['size']
            file_obj = content_data['file_obj'] = self._f.File(self.host,
                                                  file_path,
                                                  size=size,
                                                  profile=profile
                                                  )
            file_obj.eof.addCallback(lambda dummy: file_obj.close())
        else:
            log.warning(u"FIXME: unmanaged action {}".format(action))
        return desc_elt


class XEP_0234_handler(XMPPHandler):
    implements(iwokkel.IDisco)

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

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