Modify README and add .toggle_main

Add docs into README.md and add `.toggle_main` to hide messages from #main. if #main has been renamed, `.toggle_main` will reflect those changes.

README.md

@@ -1 +1,32 @@
-chat-channels
+# chat_channels
+
+A client-side mod for Minetest that adds chat channels, inspired by
+  [beerchat](https://github.com/evrooije/beerchat).
+
+## Chat channels
+
+Channels are sent via PMs to users.
+Anyone can add you to a channel without your permission, and channels are not
+  synced between users.
+Chat channels are created automatically when adding the first user and deleted
+  when removing the last user.
+
+The following channel prefixes exist:
+
+ - `@`: A PM. This will PM the user after the `@`.
+ - `#`: A channel. This is just a group PM prefixed with the channel name. If
+   a user in the channel uses chat_channels and has you in a channel with the
+   same name, the message will display as a chat message in the channel.
+   Otherwise, it will display as a PM prefixed in `-#channel-`.
+
+## Added commands
+
+ - `.add_to_channel <victim> [channel]`: Adds `<victim>` to the channel. If
+   `[channel]` is not specified, the current channel will be used instead.
+ - `.delete_channel <channel>`: Deletes a channel.
+ - `.list_channels`: Displays a list of channels.
+ - `.toggle_main`: Toggles between showing and hiding messages from #main.
+ - `.remove_from_channel <victim> [channel]`: The same as `.add_to_channel`,
+   except removes users instead.
+ - `.who [channel]`: Displays a list of users in the channel. If `[channel]` is
+   not specified, the current channel will be used.

init.lua

@@ -12,6 +12,7 @@ local messages_sent = 0
 local buffer = {}
 local msgprefix
 local localplayer = '[you]'
+local show_main_channel = true
 
 if storage:get_string('channels') then
     channels = loadstring(storage:get_string('channels'))()
@@ -59,12 +60,14 @@ local get_channel_users = function(c)
             if u then
                 channels[name] = false
             end
+            show_main_channel = true
             channel = main_channel
             return false
         end
     elseif prefix == '@' then
         return {name}
     else
+        show_main_channel = true
         channel = main_channel
         return false
     end
@@ -84,6 +87,9 @@ minetest.register_on_sending_chat_messages(function(msg)
             if cmdprefix == '@' or channels[msg:sub(2)] or msg == main_channel
               then
                 channel = msg
+                if channel == main_channel then 
+                    show_main_channel = true
+                end
                 minetest.display_chat_message('You have changed chat channels to '
                     .. channel)
                 return true
@@ -92,6 +98,7 @@ minetest.register_on_sending_chat_messages(function(msg)
             msg = ''
         end
         if c == main_channel then
+            show_main_channel = true
             minetest.send_chat_message(msg)
             return true
         elseif cmdprefix == '#' and not channels[c:sub(2)] then
@@ -124,6 +131,7 @@ minetest.register_on_receiving_chat_messages(function(msg)
           return true
         end
     elseif m:sub(1, 1) == '<' then
+        if not show_main_channel then return true end
         local hijack = false
         if channel == main_channel then
             for _ in pairs(channels) do
@@ -254,6 +262,26 @@ minetest.register_chatcommand('delete_channel', {
     end
 })
 
+minetest.register_chatcommand('toggle_' .. main_channel:sub(2), {
+    params = "",
+    description = "Toggle between showing and hiding messages from "
+        .. main_channel .. ".",
+    func = function(c)
+        if not show_main_channel then
+            show_main_channel = true
+            return true, "You will now start to receive messages from "
+                .. main_channel .. "."
+        elseif channel == main_channel then
+            return false, "You are currently in " .. main_channel
+                .. "! Please change channels first."
+        else
+            show_main_channel = false
+            return true, "You will no longer receive messages from "
+                .. main_channel .. "."
+        end
+    end
+})
+
 minetest.register_chatcommand('who', {
     params = "[channel]",
     description = "List players in the current chat channel.",