text: # Slixmpp: The Slick XMPP Library
  # Copyright (C) 2012 Nathanael C. Fritz,
  # Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
  # This file is part of Slixmpp.
  # See the file LICENSE for copying permission.
  import logging
  import hashlib
  
  from asyncio import Future
  from typing import Optional
  
  from slixmpp import JID
  from slixmpp.stanza import Iq, Message, Presence
  from slixmpp.xmlstream.handler import CoroutineCallback
  from slixmpp.xmlstream.matcher import StanzaPath
  from slixmpp.xmlstream import register_stanza_plugin
  from slixmpp.plugins.base import BasePlugin
  from slixmpp.plugins.xep_0231 import BitsOfBinary
  
  
  log = logging.getLogger(__name__)
  
  
  class XEP_0231(BasePlugin):
  
      """
      XEP-0231 Bits of Binary
      """
  
      name = 'xep_0231'
      description = 'XEP-0231: Bits of Binary'
      dependencies = {'xep_0030'}
  
      def plugin_init(self):
          self._cids = {}
  
          register_stanza_plugin(Iq, BitsOfBinary)
          register_stanza_plugin(Message, BitsOfBinary)
          register_stanza_plugin(Presence, BitsOfBinary)
  
          self.xmpp.register_handler(
              CoroutineCallback('Bits of Binary - Iq',
                  StanzaPath('iq/bob'),
                  self._handle_bob_iq))
  
          self.xmpp.register_handler(
              CoroutineCallback('Bits of Binary - Message',
                  StanzaPath('message/bob'),
                  self._handle_bob))
  
          self.xmpp.register_handler(
              CoroutineCallback('Bits of Binary - Presence',
                  StanzaPath('presence/bob'),
                  self._handle_bob))
  
          self.api.register(self._get_bob, 'get_bob', default=True)
          self.api.register(self._set_bob, 'set_bob', default=True)
          self.api.register(self._del_bob, 'del_bob', default=True)
  
      def plugin_end(self):
          self.xmpp['xep_0030'].del_feature(feature='urn:xmpp:bob')
          self.xmpp.remove_handler('Bits of Binary - Iq')
          self.xmpp.remove_handler('Bits of Binary - Message')
          self.xmpp.remove_handler('Bits of Binary - Presence')
  
      def session_bind(self, jid):
          self.xmpp['xep_0030'].add_feature('urn:xmpp:bob')
  
      async def set_bob(self, data: bytes, mtype: str, cid: Optional[str] = None,
                        max_age: Optional[int] = None) -> str:
          """Register a blob of binary data as a BOB.
  
          .. versionchanged:: 1.8.0
              If ``max_age`` is specified, the registered data will be destroyed
              after that time.
              This function is now a coroutine.
  
          :param data: Data to register.
          :param mtype: Mime Type of the data (e.g. ``image/jpeg``).
          :param cid: Content-ID (will be auto-generated if left out).
          :param max_age: Duration of content availability.
          :returns: The cid value.
          """
          if cid is None:
              cid = 'sha1+%s@bob.xmpp.org' % hashlib.sha1(data).hexdigest()
  
          bob = BitsOfBinary()
          bob['data'] = data
          bob['type'] = mtype
          bob['cid'] = cid
          if max_age is not None:
              bob['max_age'] = max_age
  
          await self.api['set_bob'](args=bob)
          # Schedule destruction of the data
          if max_age is not None and max_age > 0:
              self.xmpp.loop.call_later(max_age, self.del_bob,  cid)
          return cid
  
      async def get_bob(self, jid: Optional[JID] = None, cid: Optional[str] = None,
                        cached: bool = True, ifrom: Optional[JID] = None,
                        **iqkwargs) -> Iq:
          """Get a BOB.
  
          .. versionchanged:: 1.8.0
              Results not in cache do not raise an error when ``cached`` is True.
              This function is now a coroutine.
  
          :param jid: JID to fetch the BOB from.
          :param cid: Content ID (actually required).
          :param cached: To fetch the BOB from the local cache first (from CID only)
          """
          if cached:
              data = await self.api['get_bob'](None, None, ifrom, args=cid)
              if data is not None:
                  if not isinstance(data, Iq):
                      iq = self.xmpp.Iq()
                      iq.append(data)
                      return iq
                  return data
  
          iq = self.xmpp.make_iq_get(ito=jid, ifrom=ifrom)
          iq['bob']['cid'] = cid
          return await iq.send(**iqkwargs)
  
      def del_bob(self, cid: str) -> Future:
          """Delete a stored BoB.
  
          .. versionchanged:: 1.8.0
              This function now returns a Future.
          """
          return self.api['del_bob'](args=cid)
  
      async def _handle_bob_iq(self, iq: Iq):
          cid = iq['bob']['cid']
  
          if iq['type'] == 'result':
              await self.api['set_bob'](iq['from'], None, iq['to'], args=iq['bob'])
              self.xmpp.event('bob', iq)
          elif iq['type'] == 'get':
              data = await self.api['get_bob'](iq['to'], None, iq['from'], args=cid)
              if isinstance(data, Iq):
                  data['id'] = iq['id']
                  data.send()
                  return
  
              iq = iq.reply()
              iq.append(data)
              iq.send()
  
      async def _handle_bob(self, stanza):
          await self.api['set_bob'](
              stanza['from'], None,
              stanza['to'], args=stanza['bob']
          )
          self.xmpp.event('bob', stanza)
  
      # =================================================================
  
      def _set_bob(self, jid, node, ifrom, bob):
          self._cids[bob['cid']] = bob
  
      def _get_bob(self, jid, node, ifrom, cid):
          if cid in self._cids:
              return self._cids[cid]
  
      def _del_bob(self, jid, node, ifrom, cid):
          if cid in self._cids:
              del self._cids[cid]
  