Implement "partial" message events.

These are events that get triggered regardless of the state of the
message cache. Useful for getting data from before the bot was booted.

7 files changed, 178 insertions, 26 deletions

diff --git a/discord/__init__.py b/discord/__init__.py
index 32ff5b02..5efdd74a 100644
--- a/discord/__init__.py
+++ b/discord/__init__.py
@@ -20,7 +20,7 @@ __version__ = '1.0.0a'
 from .client import Client, AppInfo
 from .user import User, ClientUser, Profile
 from .game import Game
-from .emoji import Emoji, PartialEmoji
+from .emoji import Emoji, PartialReactionEmoji
 from .channel import *
 from .guild import Guild
 from .relationship import Relationship
diff --git a/discord/emoji.py b/discord/emoji.py
index 8c880b5d..0c161c6c 100644
--- a/discord/emoji.py
+++ b/discord/emoji.py
@@ -30,7 +30,55 @@ from collections import namedtuple
 from . import utils
 from .mixins import Hashable
 
-PartialEmoji = namedtuple('PartialEmoji', 'id name')
+class PartialReactionEmoji(namedtuple('PartialReactionEmoji', 'name id')):
+    """Represents a "partial" reaction emoji.
+
+    This model will be given in two scenarios:
+
+    - "Raw" data events such as :func:`on_raw_reaction_add`
+    - Custom emoji that the bot cannot see from e.g. :attr:`Message.reactions`
+
+    .. container:: operations
+
+        .. describe:: x == y
+
+            Checks if two emoji are the same.
+
+        .. describe:: x != y
+
+            Checks if two emoji are not the same.
+
+        .. describe:: hash(x)
+
+            Return the emoji's hash.
+
+        .. describe:: str(x)
+
+            Returns the emoji rendered for discord.
+
+    Attributes
+    -----------
+    name: str
+        The custom emoji name, if applicable, or the unicode codepoint
+        of the non-custom emoji.
+    id: Optional[int]
+        The ID of the custom emoji, if applicable.
+    """
+
+    __slots__ = ()
+
+    def __str__(self):
+        if self.id is None:
+            return self.name
+        return '<:%s:%s>' % (self.name, self.id)
+
+    def is_custom_emoji(self):
+        """Checks if this is a custom non-Unicode emoji."""
+        return self.id is not None
+
+    def is_unicode_emoji(self):
+        """Checks if this is a Unicode emoji."""
+        return self.id is None
 
 class Emoji(Hashable):
     """Represents a custom emoji.
diff --git a/discord/message.py b/discord/message.py
index 2550798f..27296117 100644
--- a/discord/message.py
+++ b/discord/message.py
@@ -198,10 +198,9 @@ class Message:
             else:
                 setattr(self, key, transform(value))
 
-    def _add_reaction(self, data):
-        emoji = self._state.get_reaction_emoji(data['emoji'])
+    def _add_reaction(self, data, emoji, user_id):
         reaction = utils.find(lambda r: r.emoji == emoji, self.reactions)
-        is_me = data['me'] = int(data['user_id']) == self._state.self_id
+        is_me = data['me'] = user_id == self._state.self_id
 
         if reaction is None:
             reaction = Reaction(message=self, data=data, emoji=emoji)
@@ -213,8 +212,7 @@ class Message:
 
         return reaction
 
-    def _remove_reaction(self, data):
-        emoji = self._state.get_reaction_emoji(data['emoji'])
+    def _remove_reaction(self, data, emoji, user_id):
         reaction = utils.find(lambda r: r.emoji == emoji, self.reactions)
 
         if reaction is None:
@@ -225,7 +223,7 @@ class Message:
         # sent bad data, or we stored improperly
         reaction.count -= 1
 
-        if int(data['user_id']) == self._state.self_id:
+        if user_id == self._state.self_id:
             reaction.me = False
         if reaction.count == 0:
             # this raises ValueError if something went wrong as well.
diff --git a/discord/reaction.py b/discord/reaction.py
index 833f1b3d..91c606d9 100644
--- a/discord/reaction.py
+++ b/discord/reaction.py
@@ -67,7 +67,7 @@ class Reaction:
 
     def __init__(self, *, message, data, emoji=None):
         self.message = message
-        self.emoji = message._state.get_reaction_emoji(data['emoji']) if emoji is None else emoji
+        self.emoji = emoji or message._state.get_reaction_emoji(data['emoji'])
         self.count = data.get('count', 1)
         self.me = data.get('me')
 
diff --git a/discord/state.py b/discord/state.py
index aaa3aa54..67f8f763 100644
--- a/discord/state.py
+++ b/discord/state.py
@@ -26,7 +26,7 @@ DEALINGS IN THE SOFTWARE.
 
 from .guild import Guild
 from .user import User, ClientUser
-from .emoji import Emoji, PartialEmoji
+from .emoji import Emoji, PartialReactionEmoji
 from .message import Message
 from .relationship import Relationship
 from .channel import *
@@ -35,6 +35,7 @@ from .role import Role
 from .enums import ChannelType, try_enum, Status
 from .calls import GroupCall
 from . import utils, compat
+from .embeds import Embed
 
 from collections import deque, namedtuple
 import copy, enum, math
@@ -314,20 +315,27 @@ class ConnectionState:
 
     def parse_message_delete(self, data):
         message_id = int(data['id'])
+        channel_id = int(data['channel_id'])
+        self.dispatch('raw_message_delete', message_id, channel_id)
+
         found = self._get_message(message_id)
         if found is not None:
             self.dispatch('message_delete', found)
             self._messages.remove(found)
 
     def parse_message_delete_bulk(self, data):
-        message_ids = set(map(int, data.get('ids', [])))
-        to_be_deleted = list(filter(lambda m: m.id in message_ids, self._messages))
+        message_ids = { int(x) for x in data.get('ids', []) }
+        channel_id = int(data['channel_id'])
+        self.dispatch('raw_bulk_message_delete', message_ids, channel_id)
+        to_be_deleted = [message for message in self._messages if message.id in message_ids]
         for msg in to_be_deleted:
             self.dispatch('message_delete', msg)
             self._messages.remove(msg)
 
     def parse_message_update(self, data):
-        message = self._get_message(int(data['id']))
+        message_id = int(data['id'])
+        self.dispatch('raw_message_edit', message_id, data)
+        message = self._get_message(message_id)
         if message is not None:
             older_message = copy.copy(message)
             if 'call' in data:
@@ -335,36 +343,61 @@ class ConnectionState:
                 message._handle_call(data['call'])
             elif 'content' not in data:
                 # embed only edit
-                message.embeds = data['embeds']
+                message.embeds = [Embed.from_data(d) for d in data['embeds']]
             else:
                 message._update(channel=message.channel, data=data)
 
             self.dispatch('message_edit', older_message, message)
 
     def parse_message_reaction_add(self, data):
-        message = self._get_message(int(data['message_id']))
+        message_id = int(data['message_id'])
+        user_id = int(data['user_id'])
+        channel_id = int(data['channel_id'])
+
+        emoji_data = data['emoji']
+        emoji_id = utils._get_as_snowflake(emoji_data, 'id')
+        emoji = PartialReactionEmoji(id=emoji_id, name=emoji_data['name'])
+        self.dispatch('raw_reaction_add', emoji, message_id, channel_id, user_id)
+
+        # rich interface here
+        message = self._get_message(message_id)
         if message is not None:
-            reaction = message._add_reaction(data)
-            user = self._get_reaction_user(message.channel, int(data['user_id']))
+            emoji = self._upgrade_partial_emoji(emoji)
+            reaction = message._add_reaction(data, emoji, user_id)
+            user = self._get_reaction_user(message.channel, user_id)
             if user:
                 self.dispatch('reaction_add', reaction, user)
 
     def parse_message_reaction_remove_all(self, data):
-        message =  self._get_message(int(data['message_id']))
+        message_id = int(data['message_id'])
+        channel_id = int(data['channel_id'])
+        self.dispatch('raw_reaction_clear', message_id, channel_id)
+
+        message =  self._get_message(message_id)
         if message is not None:
             old_reactions = message.reactions.copy()
             message.reactions.clear()
             self.dispatch('reaction_clear', message, old_reactions)
 
     def parse_message_reaction_remove(self, data):
-        message = self._get_message(int(data['message_id']))
+        message_id = int(data['message_id'])
+        user_id = int(data['user_id'])
+        channel_id = int(data['channel_id'])
+
+        emoji_data = data['emoji']
+        emoji_id = utils._get_as_snowflake(emoji_data, 'id')
+        emoji = PartialReactionEmoji(id=emoji_id, name=emoji_data['name'])
+        self.dispatch('raw_reaction_remove', emoji, message_id, channel_id, user_id)
+
+        message = self._get_message(message_id)
         if message is not None:
+            emoji = self._upgrade_partial_emoji(emoji)
             try:
-                reaction = message._remove_reaction(data)
+                reaction = message._remove_reaction(data, emoji, user_id)
             except (AttributeError, ValueError) as e: # eventual consistency lol
                 pass
             else:
-                user = self._get_reaction_user(message.channel, int(data['user_id']))
+                user = self._get_reaction_user(message.channel, user_id)
                 if user:
                     self.dispatch('reaction_remove', reaction, user)
 
@@ -790,7 +823,13 @@ class ConnectionState:
         try:
             return self._emojis[emoji_id]
         except KeyError:
-            return PartialEmoji(id=emoji_id, name=data['name'])
+            return PartialReactionEmoji(id=emoji_id, name=data['name'])
+
+    def _upgrade_partial_emoji(self, emoji):
+        try:
+            return self._emojis[emoji.id]
+        except KeyError:
+            return emoji
 
     def get_channel(self, id):
         if id is None:
diff --git a/discord/utils.py b/discord/utils.py
index 35044836..06aa5a35 100644
--- a/discord/utils.py
+++ b/discord/utils.py
@@ -237,9 +237,7 @@ def _get_as_snowflake(data, key):
     except KeyError:
         return None
     else:
-        if value is None:
-            return value
-        return int(value)
+        return value and int(value)
 
 def _get_mime_type_for_image(data):
     if data.startswith(b'\x89\x50\x4E\x47\x0D\x0A\x1A\x0A'):
diff --git a/docs/api.rst b/docs/api.rst
index cb0716a0..53ce4051 100644
--- a/docs/api.rst
+++ b/docs/api.rst
@@ -232,6 +232,23 @@ to handle it, which defaults to print a traceback and ignoring the exception.
 
     :param message: A :class:`Message` of the deleted message.
 
+.. function:: on_raw_message_delete(message_id, channel_id)
+
+    Called when a message is deleted. Unlike :func:`on_message_delete`, this is
+    called regardless of the message being in the internal message cache or not.
+
+    :param int message_id: The message ID of the message being deleted.
+    :param int channel_id: The channel ID where the message was deleted.
+
+.. function:: on_raw_bulk_message_delete(message_ids, channel_id)
+
+    Called when a bulk delete is triggered. This event is called regardless
+    of the message IDs being in the internal message cache or not.
+
+    :param message_ids: The message IDs that were bulk deleted.
+    :type message_ids: Set[int]
+    :param int channel_id: The channel ID where the messages were deleted.
+
 .. function:: on_message_edit(before, after)
 
     Called when a :class:`Message` receives an update event. If the message is not found
@@ -252,6 +269,22 @@ to handle it, which defaults to print a traceback and ignoring the exception.
     :param before: A :class:`Message` of the previous version of the message.
     :param after: A :class:`Message` of the current version of the message.
 
+.. function:: on_raw_message_edit(message_id, data)
+
+    Called when a message is edited. Unlike :func:`on_message_edit`, this is called
+    regardless of the state of the internal message cache.
+
+    Due to the inherently raw nature of this event, the data parameter coincides with
+    the raw data given by the `gateway <https://discordapp.com/developers/docs/topics/gateway#message-update>`_
+
+    Since the data payload can be partial, care must be taken when accessing stuff in the dictionary.
+    One example of a common case of partial data is when the ``'content'`` key is inaccessible. This
+    denotes an "embed" only edit, which is an edit in which only the embeds are updated by the Discord
+    embed server.
+
+    :param int message_id: The message ID of the message being edited.
+    :param dict data: The raw data being passed to the MESSAGE_UPDATE gateway event.
+
 .. function:: on_reaction_add(reaction, user)
 
     Called when a message has a reaction added to it. Similar to on_message_edit,
@@ -265,6 +298,17 @@ to handle it, which defaults to print a traceback and ignoring the exception.
     :param reaction: A :class:`Reaction` showing the current state of the reaction.
     :param user: A :class:`User` or :class:`Member` of the user who added the reaction.
 
+.. function:: on_raw_reaction_add(emoji, message_id, channel_id, user_id)
+
+    Called when a reaction has a reaction added. Unlike :func:`on_reaction_add`, this is
+    called regardless of the state of the internal message cache.
+
+    :param emoji: The custom or unicode emoji being reacted to.
+    :type emoji: :class:`PartialReactionEmoji`
+    :param int message_id: The message ID of the message being reacted.
+    :param int channel_id: The channel ID where the message belongs to.
+    :param int user_id: The user ID of the user who did the reaction.
+
 .. function:: on_reaction_remove(reaction, user)
 
     Called when a message has a reaction removed from it. Similar to on_message_edit,
@@ -278,15 +322,34 @@ to handle it, which defaults to print a traceback and ignoring the exception.
     :param reaction: A :class:`Reaction` showing the current state of the reaction.
     :param user: A :class:`User` or :class:`Member` of the user who removed the reaction.
 
+.. function:: on_raw_reaction_remove(emoji, message_id, channel_id, user_id)
+
+    Called when a reaction has a reaction removed. Unlike :func:`on_reaction_remove`, this is
+    called regardless of the state of the internal message cache.
+
+    :param emoji: The custom or unicode emoji that got un-reacted.
+    :type emoji: :class:`PartialReactionEmoji`
+    :param int message_id: The message ID of the message being un-reacted.
+    :param int channel_id: The channel ID where the message belongs to.
+    :param int user_id: The user ID of the user who removed the reaction.
+
 .. function:: on_reaction_clear(message, reactions)
 
-    Called when a message has all its reactions removed from it. Similar to on_message_edit,
+    Called when a message has all its reactions removed from it. Similar to :func:`on_message_edit`,
     if the message is not found in the :attr:`Client.messages` cache, then this event
     will not be called.
 
     :param message: The :class:`Message` that had its reactions cleared.
     :param reactions: A list of :class:`Reaction`\s that were removed.
 
+.. function:: on_raw_reaction_clear(message_id, channel_id)
+
+    Called when a message has all its reactions removed. Unlike :func:`on_reaction_clear`,
+    this is called regardless of the state of the internal message cache.
+
+    :param int message_id: The message ID of the message having its reactions removed.
+    :param int channel_id: The channel ID of where the message belongs to.
+
 .. function:: on_private_channel_delete(channel)
               on_private_channel_create(channel)
 
@@ -1687,6 +1750,12 @@ Emoji
 .. autoclass:: Emoji
     :members:
 
+PartialReactionEmoji
+~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: PartialReactionEmoji
+    :members:
+
 Role
 ~~~~~