storage: add Storage.get_reactions

This finishes basic reaction code (both inserting and putting a reaction).

SQL for instances:
```sql
DROP TABLE message_reactions;
```

Then rerun `schema.sql`

 - channel.reactions: fix partial_emoji
 - schema.sql: add message_reactions.react_ts and unique constraint
    instead of primary key

litecord/blueprints/channel/messages.py

@@ -81,7 +81,7 @@ async def get_messages(channel_id):
     result = []
 
     for message_id in message_ids:
-        msg = await app.storage.get_message(message_id['id'])
+        msg = await app.storage.get_message(message_id['id'], user_id)
 
         if msg is None:
             continue
@@ -98,7 +98,7 @@ async def get_single_message(channel_id, message_id):
     await channel_check(user_id, channel_id)
 
     # TODO: check READ_MESSAGE_HISTORY permissions
-    message = await app.storage.get_message(message_id)
+    message = await app.storage.get_message(message_id, user_id)
 
     if not message:
         raise MessageNotFound()
@@ -168,7 +168,7 @@ async def create_message(channel_id):
         MessageType.DEFAULT.value
     )
 
-    payload = await app.storage.get_message(message_id)
+    payload = await app.storage.get_message(message_id, user_id)
     
     if ctype == ChannelType.DM:
         # guild id here is the peer's ID.
@@ -218,7 +218,7 @@ async def edit_message(channel_id, message_id):
 
     # TODO: update embed
 
-    message = await app.storage.get_message(message_id)
+    message = await app.storage.get_message(message_id, user_id)
 
     # only dispatch MESSAGE_UPDATE if we actually had any update to start with
     if updated:

litecord/blueprints/channel/reactions.py

@@ -47,10 +47,11 @@ def emoji_info_from_str(emoji: str) -> tuple:
     return emoji_type, emoji_id, emoji_name
 
 
-def _partial_emoji(emoji_type, emoji_id, emoji_name) -> dict:
+def partial_emoji(emoji_type, emoji_id, emoji_name) -> dict:
+    print(emoji_type, emoji_id, emoji_name)
     return {
-        'id': None if emoji_type.UNICODE else emoji_id,
-        'name': emoji_id if emoji_type.UNICODE else emoji_name
+        'id': None if emoji_type == EmojiType.UNICODE else emoji_id,
+        'name': emoji_name if emoji_type == EmojiType.UNICODE else emoji_id
     }
 
 
@@ -88,7 +89,7 @@ async def add_reaction(channel_id: int, message_id: int, emoji: str):
         emoji_id if emoji_type == EmojiType.UNICODE else None
     )
 
-    partial = _partial_emoji(emoji_type, emoji_id, emoji_name)
+    partial = partial_emoji(emoji_type, emoji_id, emoji_name)
     payload = _make_payload(user_id, channel_id, message_id, partial)
 
     if ctype in GUILD_CHANS:
@@ -100,7 +101,7 @@ async def add_reaction(channel_id: int, message_id: int, emoji: str):
     return '', 204
 
 
-def _emoji_sql(emoji_type, emoji_id, emoji_name, param=4):
+def emoji_sql(emoji_type, emoji_id, emoji_name, param=4):
     """Extract SQL clauses to search for specific emoji
     in the message_reactions table."""
     param = f'${param}'
@@ -120,7 +121,7 @@ def _emoji_sql_simple(emoji: str, param=4):
     """Simpler version of _emoji_sql for functions that
     don't need the results from emoji_info_from_str."""
     emoji_type, emoji_id, emoji_name = emoji_info_from_str(emoji)
-    return _emoji_sql(emoji_type, emoji_id, emoji_name, param)
+    return emoji_sql(emoji_type, emoji_id, emoji_name, param)
 
 
 async def remove_reaction(channel_id: int, message_id: int,
@@ -128,7 +129,7 @@ async def remove_reaction(channel_id: int, message_id: int,
     ctype, guild_id = await channel_check(user_id, channel_id)
 
     emoji_type, emoji_id, emoji_name = emoji_info_from_str(emoji)
-    where_ext, main_emoji = _emoji_sql(emoji_type, emoji_id, emoji_name)
+    where_ext, main_emoji = emoji_sql(emoji_type, emoji_id, emoji_name)
 
     await app.db.execute(
         f"""
@@ -139,7 +140,7 @@ async def remove_reaction(channel_id: int, message_id: int,
           {where_ext}
         """, message_id, user_id, emoji_type, main_emoji)
 
-    partial = _partial_emoji(emoji_type, emoji_id, emoji_name)
+    partial = partial_emoji(emoji_type, emoji_id, emoji_name)
     payload = _make_payload(user_id, channel_id, message_id, partial)
 
     if ctype in GUILD_CHANS:

litecord/storage.py

@@ -5,6 +5,9 @@ from logbook import Logger
 
 from .enums import ChannelType, RelationshipType
 from .schemas import USER_MENTION, ROLE_MENTION
+from litecord.blueprints.channel.reactions import (
+    emoji_info_from_str, EmojiType, emoji_sql, partial_emoji
+)
 
 
 log = Logger(__name__)
@@ -553,7 +556,72 @@ class Storage:
 
         return res
 
-    async def get_message(self, message_id: int) -> Dict:
+    async def get_reactions(self, message_id: int, user_id=None) -> List:
+        """Get all reactions in a message."""
+        reactions = await self.db.fetch("""
+        SELECT user_id, emoji_type, emoji_id, emoji_text
+        FROM message_reactions
+        ORDER BY react_ts
+        """)
+
+        # ordered list of emoji
+        emoji = []
+
+        # the current state of emoji info
+        react_stats = {}
+
+        # to generate the list, we pass through all
+        # all reactions and insert them all.
+
+        # we can't use a set() because that
+        # doesn't guarantee any order.
+        for row in reactions:
+            etype = EmojiType(row['emoji_type'])
+            eid, etext = row['emoji_id'], row['emoji_text']
+
+            # get the main key to use, given
+            # the emoji information
+            _, main_emoji = emoji_sql(etype, eid, etext)
+
+            if main_emoji in emoji:
+                continue
+
+            # maintain order (first reacted comes first
+            # on the reaction list)
+            emoji.append(main_emoji)
+
+            react_stats[main_emoji] = {
+                'count': 0,
+                'me': False,
+                'emoji': partial_emoji(etype, eid, etext)
+            }
+
+        # then the 2nd pass, where we insert
+        # the info for each reaction in the react_stats
+        # dictionary
+        for row in reactions:
+            etype = EmojiType(row['emoji_type'])
+            eid, etext = row['emoji_id'], row['emoji_text']
+
+            # same thing as the last loop,
+            # extracting main key
+            _, main_emoji = emoji_sql(etype, eid, etext)
+
+            stats = react_stats[main_emoji]
+            stats['count'] += 1
+
+            print(row['user_id'], user_id)
+            if row['user_id'] == user_id:
+                stats['me'] = True
+
+        # after processing reaction counts,
+        # we get them in the same order
+        # they were defined in the first loop.
+        print(emoji)
+        print(react_stats)
+        return list(map(react_stats.get, emoji))
+
+    async def get_message(self, message_id: int, user_id=None) -> Dict:
         """Get a single message's payload."""
         row = await self.db.fetchrow("""
         SELECT id::text, channel_id::text, author_id, content,
@@ -614,6 +682,8 @@ class Storage:
         res['mention_roles'] = await self._msg_regex(
             ROLE_MENTION, _get_role_mention, content)
 
+        res['reactions'] = await self.get_reactions(message_id, user_id)
+
         # TODO: handle webhook authors
         res['author'] = await self.get_user(res['author_id'])
         res.pop('author_id')
@@ -624,9 +694,6 @@ class Storage:
         # TODO: res['embeds']
         res['embeds'] = []
 
-        # TODO: res['reactions']
-        res['reactions'] = []
-
         # TODO: res['pinned']
         res['pinned'] = False
 

schema.sql

@@ -528,15 +528,18 @@ CREATE TABLE IF NOT EXISTS message_reactions (
     message_id bigint REFERENCES messages (id),
     user_id bigint REFERENCES users (id),
 
+    react_ts timestamp without time zone default (now() at time zone 'utc'),
+
     -- emoji_type = 0 -> custom emoji
     -- emoji_type = 1 -> unicode emoji
     emoji_type int DEFAULT 0,
     emoji_id bigint REFERENCES guild_emoji (id),
-    emoji_text text,
-
-    PRIMARY KEY (message_id, user_id, emoji_id, emoji_text)
+    emoji_text text
 );
 
+ALTER TABLE message_reactions ADD CONSTRAINT message_reactions_main_uniq
+    UNIQUE (message_id, user_id, emoji_id, emoji_text);
+
 CREATE TABLE IF NOT EXISTS channel_pins (
     channel_id bigint REFERENCES channels (id) ON DELETE CASCADE,
     message_id bigint REFERENCES messages (id) ON DELETE CASCADE,