Allow customizing chat message format (#8529)

builtin/game/chat.lua

@@ -1,4 +1,29 @@
--- Minetest: builtin/game/chatcommands.lua
+-- Minetest: builtin/game/chat.lua
+
+--
+-- Chat message formatter
+--
+
+-- Implemented in Lua to allow redefinition
+function core.format_chat_message(name, message)
+	local str = core.settings:get("chat_message_format")
+	local error_str = "Invalid chat message format - missing %s"
+	local i
+
+	str, i = str:gsub("@name", name, 1)
+	if i == 0 then
+		error(error_str:format("@name"), 2)
+	end
+
+	str, i = str:gsub("@message", message, 1)
+	if i == 0 then
+		error(error_str:format("@message"), 2)
+	end
+
+	str = str:gsub("@timestamp", os.date("%H:%M:%S", os.time()), 1)
+
+	return str
+end
 
 --
 -- Chat command handler

builtin/game/init.lua

@@ -24,7 +24,7 @@ dofile(gamepath.."misc.lua")
 dofile(gamepath .. "privileges.lua")
 dofile(gamepath .. "auth.lua")
 dofile(commonpath .. "chatcommands.lua")
-dofile(gamepath.."chatcommands.lua")
+dofile(gamepath .. "chat.lua")
 dofile(commonpath .. "information_formspecs.lua")
 dofile(gamepath .. "static_spawn.lua")
 dofile(gamepath .. "detached_inventory.lua")

builtin/settingtypes.txt

@@ -1058,6 +1058,10 @@ disable_anticheat (Disable anticheat) bool false
 #    This option is only read when server starts.
 enable_rollback_recording (Rollback recording) bool false
 
+#    Format of player chat messages. The following strings are valid placeholders:
+#    @name, @message, @timestamp (optional)
+chat_message_format (Chat message format) string <@name> @message
+
 #    A message to be displayed to all clients when the server shuts down.
 kick_msg_shutdown (Shutdown message) string Server shutting down.
 

doc/lua_api.txt

@@ -4156,6 +4156,12 @@ Chat
 
 * `minetest.chat_send_all(text)`
 * `minetest.chat_send_player(name, text)`
+* `minetest.format_chat_message(name, message)`
+    * Used by the server to format a chat message, based on the setting `chat_message_format`.
+      Refer to the documentation of the setting for a list of valid placeholders.
+    * Takes player name and message, and returns the formatted string to be sent to players.
+    * Can be redefined by mods if required, for things like colored names or messages.
+    * **Only** the first occurrence of each placeholder will be replaced.
 
 Environment access
 ------------------

minetest.conf.example

@@ -1277,6 +1277,11 @@
 #    type: bool
 # enable_rollback_recording = false
 
+#    Format of player chat messages. The following strings are valid placeholders:
+#    @name, @message, @timestamp (optional)
+#    type: string
+chat_message_format = <@name> @message
+
 #    A message to be displayed to all clients when the server shuts down.
 #    type: string
 # kick_msg_shutdown = Server shutting down.

src/defaultsettings.cpp

@@ -356,6 +356,7 @@ void set_default_settings(Settings *settings)
 	settings->setDefault("kick_msg_crash", "This server has experienced an internal error. You will now be disconnected.");
 	settings->setDefault("ask_reconnect_on_crash", "false");
 
+	settings->setDefault("chat_message_format", "<@name> @message");
 	settings->setDefault("profiler_print_interval", "0");
 	settings->setDefault("active_object_send_range_blocks", "4");
 	settings->setDefault("active_block_range", "3");

src/gettime.h

@@ -19,7 +19,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #pragma once
 
-#include "irrlichttypes.h"
 #include <ctime>
 #include <string>
 

src/script/cpp_api/s_server.cpp

@@ -168,3 +168,25 @@ void ScriptApiServer::on_shutdown()
 	runCallbacks(0, RUN_CALLBACKS_MODE_FIRST);
 }
 
+std::string ScriptApiServer::formatChatMessage(const std::string &name,
+	const std::string &message)
+{
+	SCRIPTAPI_PRECHECKHEADER
+
+	// Push function onto stack
+	lua_getglobal(L, "core");
+	lua_getfield(L, -1, "format_chat_message");
+
+	// Push arguments onto stack
+	lua_pushstring(L, name.c_str());
+	lua_pushstring(L, message.c_str());
+
+	// Actually call the function
+	lua_call(L, 2, 1);
+
+	// Fetch return value
+	std::string ret = lua_tostring(L, -1);
+	lua_pop(L, 1);
+
+	return ret;
+}

src/script/cpp_api/s_server.h

@@ -36,6 +36,10 @@ public:
 	// Calls on_shutdown handlers
 	void on_shutdown();
 
+	// Calls core.format_chat_message
+	std::string formatChatMessage(const std::string &name,
+		const std::string &message);
+
 	/* auth */
 	bool getAuth(const std::string &playername,
 		std::string *dst_password,

src/server.cpp

@@ -2912,10 +2912,8 @@ std::wstring Server::handleChat(const std::string &name, const std::wstring &wna
 		line += L"-!- You don't have permission to shout.";
 		broadcast_line = false;
 	} else {
-		line += L"<";
-		line += wname;
-		line += L"> ";
-		line += wmessage;
+		line += narrow_to_wide(m_script->formatChatMessage(name,
+				wide_to_narrow(wmessage)));
 	}
 
 	/*