Guild leaving / deleting didn't clean up properly

Too many wrong IFs that prevented anything from happening at all and the
chatview wasn't properly cleaned up with the corresponding function.

ui/guildlist.go

@@ -105,17 +105,12 @@ func (g *GuildList) SetOnGuildSelect(handler func(guildID string)) {
 // RemoveGuild removes the node that refers to the given guildID.
 func (g *GuildList) RemoveGuild(guildID string) {
 	children := g.GetRoot().GetChildren()
-	indexToRemove := -1
 	for index, node := range children {
 		if node.GetReference() == guildID {
-			indexToRemove = index
+			g.GetRoot().SetChildren(append(children[:index], children[index+1:]...))
 			break
 		}
 	}
-
-	if indexToRemove != -1 {
-		g.GetRoot().SetChildren(append(children[:indexToRemove], children[indexToRemove+1:]...))
-	}
 }
 
 // AddGuild adds a new node that references the given guildID and shows the
@@ -128,11 +123,9 @@ func (g *GuildList) AddGuild(guildID, name string) {
 
 // UpdateName updates the name of the guild with the given ID.
 func (g *GuildList) UpdateName(guildID, newName string) {
-	for _, node := range g.GetRoot().GetChildren() {
-		if node.GetReference() == guildID {
-			node.SetText(tviewutil.Escape(newName))
-			break
-		}
+	node := tviewutil.GetNodeByReference(guildID, g.TreeView)
+	if node != nil {
+		node.SetText(tviewutil.Escape(newName))
 	}
 }
 
@@ -144,7 +137,7 @@ func (g *GuildList) setNotificationCount(count int) {
 	}
 }
 
-func (g *GuildList) amountOfUnreadGuilds() int {
+func (g *GuildList) countUnreadGuilds() int {
 	var unreadCount int
 	for _, child := range g.GetRoot().GetChildren() {
 		if !readstate.HasGuildBeenRead((child.GetReference()).(string)) {
@@ -158,7 +151,7 @@ func (g *GuildList) amountOfUnreadGuilds() int {
 // UpdateUnreadGuildCount finds the number of guilds containing unread
 // channels and updates the title accordingly.
 func (g *GuildList) UpdateUnreadGuildCount() {
-	g.setNotificationCount(g.amountOfUnreadGuilds())
+	g.setNotificationCount(g.countUnreadGuilds())
 }
 
 // MarkAsLoaded selects the guild and marks it as loaded.

ui/window.go

@@ -1879,25 +1879,25 @@ func (window *Window) registerGuildHandlers() {
 
 	go func() {
 		for guildRemove := range guildRemoveChannel {
-			if window.selectedGuild == nil {
-				continue
-			}
-
 			if window.previousChannel != nil && window.previousChannel.GuildID == guildRemove.ID {
 				window.previousChannel = nil
 			}
 
-			if window.selectedGuild.ID == guildRemove.ID {
-				guildID := guildRemove.ID
+			guildID := guildRemove.ID
+			window.guildList.RemoveGuild(guildID)
+
+			selectedGuild := window.selectedGuild
+			if selectedGuild != nil && selectedGuild.ID == guildID {
 				window.app.QueueUpdateDraw(func() {
 					if window.selectedChannel != nil && window.selectedChannel.GuildID == guildID {
-						window.chatView.ClearViewAndCache()
-						window.selectedChannel = nil
+						window.UnloadChannel()
+						//Unload channel sets the selectedChannel as the previous
+						//one, which isn't correct.
+						window.previousChannel = nil
 					}
 
 					window.channelTree.Clear()
 					window.userList.Clear()
-					window.guildList.RemoveGuild(guildID)
 					window.selectedGuild = nil
 				})
 			}