From 34f83532dd46d852452f86196841cc3ca0ce1952 Mon Sep 17 00:00:00 2001
From: andrei <b1naryth1ef@gmail.com>
Date: Tue, 12 Apr 2016 22:25:41 -0700
Subject: [PATCH] Fix channelMap not being filled for bot users/>100 guilds

Previously we only filled the channelMap inside of READY. Because of
lazy guild loading, this was not valid for the majority of users (e.g.
bot users and users with more than 100 guilds). We now properly handle
both cases, by filling in the channelMap on GUILD_CREATE.

This commit also refactors the way we do locking inside of GUILD_CREATE
and CHANNEL_CREATE to be a bit cleaner.
---
 state.go | 32 +++++++++++++-------------------
 1 file changed, 13 insertions(+), 19 deletions(-)

diff --git a/state.go b/state.go
index 3f7ede5..9ee0f0c 100644
--- a/state.go
+++ b/state.go
@@ -45,7 +45,6 @@ func (s *State) OnReady(r *Ready) error {
 
 		for _, c := range g.Channels {
 			c.GuildID = g.ID
-
 			s.channelMap[c.ID] = c
 		}
 	}
@@ -64,16 +63,17 @@ func (s *State) GuildAdd(guild *Guild) error {
 		return ErrNilState
 	}
 
-	// Update the channels to point to the right guild
+	s.Lock()
+	defer s.Unlock()
+
+	// Update the channels to point to the right guild, adding them to the channelMap as we go
 	for _, c := range guild.Channels {
 		c.GuildID = guild.ID
+		s.channelMap[c.ID] = c
 	}
 
 	// If the guild exists, replace it.
-	if g, err := s.Guild(guild.ID); err == nil {
-		s.Lock()
-		defer s.Unlock()
-
+	if g, ok := s.guildMap[guild.ID]; ok {
 		// If this guild already exists with data, don't stomp on props.
 		if g.Unavailable != nil && !*g.Unavailable {
 			guild.Members = g.Members
@@ -86,9 +86,6 @@ func (s *State) GuildAdd(guild *Guild) error {
 		return nil
 	}
 
-	s.Lock()
-	defer s.Unlock()
-
 	s.Guilds = append(s.Guilds, guild)
 	s.guildMap[guild.ID] = guild
 
@@ -224,11 +221,11 @@ func (s *State) ChannelAdd(channel *Channel) error {
 		return ErrNilState
 	}
 
-	// If the channel exists, replace it.
-	if c, err := s.Channel(channel.ID); err == nil {
-		s.Lock()
-		defer s.Unlock()
+	s.Lock()
+	defer s.Unlock()
 
+	// If the channel exists, replace it
+	if c, ok := s.channelMap[channel.ID]; ok {
 		channel.Messages = c.Messages
 		channel.PermissionOverwrites = c.PermissionOverwrites
 
@@ -236,15 +233,12 @@ func (s *State) ChannelAdd(channel *Channel) error {
 		return nil
 	}
 
-	s.Lock()
-	defer s.Unlock()
-
 	if channel.IsPrivate {
 		s.PrivateChannels = append(s.PrivateChannels, channel)
 	} else {
-		guild, err := s.Guild(channel.GuildID)
-		if err != nil {
-			return err
+		guild, ok := s.guildMap[channel.GuildID]
+		if !ok {
+			return errors.New("Guild for channel not found.")
 		}
 
 		guild.Channels = append(guild.Channels, channel)