Update a local.

.luacheckrc

@@ -3,7 +3,7 @@ allow_defined_top = true
 
 read_globals = {
 	"DIR_DELIM",
-	"minetest", "core",
+	"core",
 	"dump",
 	"vector", "nodeupdate",
 	"VoxelManip", "VoxelArea",
@@ -11,5 +11,10 @@ read_globals = {
 	"intllib",
 	"default",
 	"rules",
+	"email",
 	table = { fields = { "copy", "getn" } }
 }
+
+globals = {
+	"minetest"
+}

depends.txt

@@ -1 +0,0 @@
-rules?

description.txt

@@ -1 +0,0 @@
-A chat filter for servers.

init.lua

@@ -25,7 +25,7 @@
 
 ]]--
 
-filter = {}
+filter = { registered_on_violations = {} }
 local words = {}
 local muted = {}
 local violations = {}
@@ -57,6 +57,10 @@ function filter.import_file(filepath)
 	end
 end
 
+function filter.register_on_violation(func)
+	table.insert(filter.registered_on_violations, func)
+end
+
 function filter.check_message(name, message)
 	for _, w in ipairs(words) do
 		if string.find(message:lower(), "%f[%a]" .. w .. "%f[%A]") then
@@ -73,22 +77,27 @@ function filter.mute(name, duration)
 		privs.shout = nil
 		minetest.set_player_privs(name, privs)
 	end
+
 	minetest.chat_send_player(name, "Watch your language! You have been temporarily muted")
 
 	muted[name] = true
 
 	minetest.after(duration * 60, function()
+		local privs = minetest.get_player_privs(name)
+		if privs.shout == true then
+			return
+		end
+
 		muted[name] = nil
 		minetest.chat_send_player(name, "Chat privilege reinstated. Please do not abuse chat.")
 
-		local privs = minetest.get_player_privs(name)
 		privs.shout = true
 		minetest.set_player_privs(name, privs)
 	end)
 end
 
 function filter.show_warning_formspec(name)
-	local formspec = "size[7,3]bgcolor[#080808BB;true]" .. default.gui_bg .. default.gui_bg_img .. [[
+	local formspec = "size[7,3]bgcolor[#080808BB;true]" .. [[
 		image[0,0;2,2;filter_warning.png]
 		label[2.3,0.5;Please watch your language!]
 	]]
@@ -111,21 +120,39 @@ function filter.on_violation(name, message)
 
 	local resolution
 
-	if violations[name] == 1 and minetest.get_player_by_name(name) then
-		resolution = "warned"
-		filter.show_warning_formspec(name)
-	elseif violations[name] <= 3 then
-		resolution = "muted"
-		filter.mute(name, 1)
-	else
-		resolution = "kicked"
-		minetest.kick_player(name, "Please mind your language!")
+	for _, cb in pairs(filter.registered_on_violations) do
+		if cb(name, message, violations) then
+			resolution = "custom"
+		end
 	end
 
-	minetest.log("action", "VIOLATION (" .. resolution .. "): <" .. name .. "> "..  message)
+	if not resolution then
+		if violations[name] == 1 and minetest.get_player_by_name(name) then
+			resolution = "warned"
+			filter.show_warning_formspec(name)
+		elseif violations[name] <= 3 then
+			resolution = "muted"
+			filter.mute(name, 1)
+		else
+			resolution = "kicked"
+			minetest.kick_player(name, "Please mind your language!")
+		end
+	end
+
+	local logmsg = "VIOLATION (" .. resolution .. "): <" .. name .. "> "..  message
+	minetest.log("action", logmsg)
+
+	local email_to = minetest.settings:get("filter.email_to")
+	if email_to and minetest.global_exists("email") then
+		email.send_mail(name, email_to, logmsg)
+	end
 end
 
 table.insert(minetest.registered_on_chat_messages, 1, function(name, message)
+	if message:sub(1, 1) == "/" then
+		return
+	end
+
 	local privs = minetest.get_player_privs(name)
 	if not privs.shout and muted[name] then
 		minetest.chat_send_player(name, "You are temporarily muted.")
@@ -138,6 +165,33 @@ table.insert(minetest.registered_on_chat_messages, 1, function(name, message)
 	end
 end)
 
+
+local function make_checker(old_func)
+	return function(name, param)
+		if not filter.check_message(name, param) then
+			filter.on_violation(name, param)
+			return false
+		end
+
+		return old_func(name, param)
+	end
+end
+
+for name, def in pairs(minetest.registered_chatcommands) do
+	if def.privs and def.privs.shout then
+		def.func = make_checker(def.func)
+	end
+end
+
+local old_register_chatcommand = minetest.register_chatcommand
+function minetest.register_chatcommand(name, def)
+	if def.privs and def.privs.shout then
+		def.func = make_checker(def.func)
+	end
+	return old_register_chatcommand(name, def)
+end
+
+
 local function step()
 	for name, v in pairs(violations) do
 		violations[name] = math.floor(v * 0.5)
@@ -145,9 +199,9 @@ local function step()
 			violations[name] = nil
 		end
 	end
-	minetest.after(2*60, step)
+	minetest.after(10*60, step)
 end
-minetest.after(2*60, step)
+minetest.after(10*60, step)
 
 minetest.register_chatcommand("filter", {
 	params = "filter server",
@@ -184,4 +238,12 @@ if minetest.global_exists("rules") and rules.show then
 	end)
 end
 
+minetest.register_on_shutdown(function()
+	for name, _ in pairs(muted) do
+		local privs = minetest.get_player_privs(name)
+		privs.shout = true
+		minetest.set_player_privs(name, privs)
+	end
+end)
+
 filter.init()

mod.conf

@@ -1 +1,3 @@
 name = filter
+description = A chat filter for servers.
+optional_depends = rules,email

readme.md

@@ -1,5 +1,4 @@
-
-## filter mod
+# filter mod
 
 This mod adds a simple chat filter. There is no default word list,
 and adding words to the filter list is done through the `/filter`
@@ -14,7 +13,26 @@ muted for 1 minute. After that, their `shout` privilege is restored.
 If they leave, their `shout` privilege is still restored, but only after
 the time expires, not before.
 
-## Bugs
+## API
 
-- the `shout` priv is permanently lost if the server shuts down while
-a player is muted.
+### Callbacks
+
+* filter.register_on_violation(func(name, message, violations))
+	* Violations is the value of the player's violation counter - which is
+	  incremented on a violation, and halved every 10 minutes.
+	* Return true if you've handled the violation. No more callbacks will be
+	  executation, and the default behaviour (warning/mute/kick) on violation
+	  will be skipped.
+
+### Methods
+
+* filter.import_file(path)
+	* Input bad words from a file (`path`) where each line is a new word.
+* filter.check_message(name, message)
+	* Checks message for violation. Returns true if okay, false if bad.
+	  If it returns false, you should cancel the sending of the message and
+	  call filter.on_violation()
+* filter.on_violation(name, message)
+	* Increments violation count, runs callbacks, and punishes the players.
+* filter.mute(name, duration)
+* filter.show_warning_formspec(name)