From 915b6224e949e628c1a994a72baf38fe2f7ec777 Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Sun, 2 Dec 2018 18:09:00 -0300
Subject: [PATCH] permissions: fix overwrite fetching in compute_overwrites

 - pubsub.guild: only send a chan action to channels user can read
---
 litecord/permissions.py  |  5 +++--
 litecord/pubsub/guild.py | 28 +++++++++++++++++-----------
 2 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/litecord/permissions.py b/litecord/permissions.py
index 2c7cee6..21369d8 100644
--- a/litecord/permissions.py
+++ b/litecord/permissions.py
@@ -177,7 +177,8 @@ async def role_permissions(guild_id: int, role_id: int,
     return perms
 
 
-async def compute_overwrites(base_perms, user_id, channel_id: int,
+async def compute_overwrites(base_perms: Permissions,
+                             user_id, channel_id: int,
                              guild_id: int = None, storage=None):
     """Compute the permissions in the context of a channel."""
     if not storage:
@@ -195,7 +196,7 @@ async def compute_overwrites(base_perms, user_id, channel_id: int,
         guild_id = await storage.guild_from_channel(channel_id)
 
     # make it a map for better usage
-    overwrites = {o['id']: o for o in overwrites}
+    overwrites = {int(o['id']): o for o in overwrites}
 
     perms = overwrite_find_mix(perms, overwrites, guild_id)
 
diff --git a/litecord/pubsub/guild.py b/litecord/pubsub/guild.py
index c53eb60..c687d25 100644
--- a/litecord/pubsub/guild.py
+++ b/litecord/pubsub/guild.py
@@ -3,6 +3,7 @@ from typing import Any
 from logbook import Logger
 
 from .dispatcher import DispatcherWithState
+from litecord.permissions import get_permissions
 
 log = Logger(__name__)
 
@@ -12,13 +13,26 @@ class GuildDispatcher(DispatcherWithState):
     KEY_TYPE = int
     VAL_TYPE = int
 
-    async def _chan_action(self, action: str, guild_id: int, user_id: int):
+    async def _chan_action(self, action: str,
+                           guild_id: int, user_id: int):
         """Send an action to all channels of the guild."""
         chan_ids = await self.app.storage.get_channel_ids(guild_id)
 
-        # TODO: check READ_MESSAGE permissions for the user
-
         for chan_id in chan_ids:
+
+            # only do an action for users that can
+            # actually read the channel to start with.
+            chan_perms = await get_permissions(
+                user_id, chan_id,
+                storage=self.main_dispatcher.app.storage)
+
+            print(user_id, chan_id, chan_perms.bits.read_messages)
+
+            if not chan_perms.bits.read_messages:
+                log.debug('skipping cid={}, no read messages',
+                          chan_id)
+                continue
+
             log.debug('sending raw action {!r} to chan={}',
                       action, chan_id)
 
@@ -42,19 +56,11 @@ class GuildDispatcher(DispatcherWithState):
     async def sub(self, guild_id: int, user_id: int):
         """Subscribe a user to the guild."""
         await super().sub(guild_id, user_id)
-
-        # when subbing a user to the guild, we should sub them
-        # to every channel they have access to, in the guild.
-
-        # TODO: check for permissions
-
         await self._chan_action('sub', guild_id, user_id)
 
     async def unsub(self, guild_id: int, user_id: int):
         """Unsubscribe a user from the guild."""
         await super().unsub(guild_id, user_id)
-
-        # same thing happening from sub() happens on unsub()
         await self._chan_action('unsub', guild_id, user_id)
 
     async def dispatch_filter(self, guild_id: int, func,