kingdoms_game/mods/voice/voice.lua

--[[
Copyright (c) 2015, Robert 'Bobby' Zenz
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--- Voice is a system to make the chat of Minetest more like a voice.
--
-- The only function that should be called from the client is activate.
voice = {
	--- Type constant for a global message.
	TYPE_GLOBAL = "global",
	
	--- Type constant for a shouted message.
	TYPE_SHOUT = "shout",
	
	--- Type constant for a talked message.
	TYPE_TALK = "talk",
	
	--- Type constant for a whispered message.
	TYPE_WHISPER = "whisper",
	
	--- If the system should be activated automatically.
	activate_automatically = settings.get_bool("voice_activate", true),
	
	--- If the system is active/has been activated.
	active = false,
	
	--- The privilege that is needed for using the global command.
	global_privilege = settings.get_string("voice_global_privilege", "voice_global"),
	
	--- The line of sight modification, which means that if the target does not
	-- have line of sight with the source, this mod will be applied to
	-- the range to limit it.
	line_of_sight_mod = settings.get_number("voice_line_of_sight_mod", 0.40),
	
	--- The callbacks for when a message is send.
	message_callbacks = List:new(),
	
	--- The parameters for talking.
	
	--- The parameters for shouting.
	shout_parameters = {
		--- Everything within this range (inclusive) will be understandable.
		understandable = settings.get_number("voice_shout_understandable", 45),
		
		--- Everything within this range (inclusive) will be abstruse, which
		-- means that only part of the message (depending on the distance) will
		-- be understandable.
		abstruse = settings.get_number("voice_shout_abstruse", 60),
		
		--- Everything within this range (inclusive) will not be understandable.
		incomprehensible = settings.get_number("voice_shout_incomprehensible", 80),
		
		-- The type of these parameters.
		type = "shout"
	},
	
	talk_parameters = {
		--- Everything within this range (inclusive) will be understandable.
		understandable = settings.get_number("voice_talk_understandable", 6),
		
		--- Everything within this range (inclusive) will be abstruse, which
		-- means that only part of the message (depending on the distance) will
		-- be understandable.
		abstruse = settings.get_number("voice_talk_abstruse", 12),
		
		--- Everything within this range (inclusive) will not be understandable.
		incomprehensible = settings.get_number("voice_talk_incomprehenisble", 17),
		
		-- The type of these parameters.
		type = "talk"
	},
	
	--- The parameters for whispering.
	whisper_parameters = {
		--- Everything within this range (inclusive) will be understandable.
		understandable = settings.get_number("voice_whisper_understandable", 3),
		
		--- Everything within this range (inclusive) will be abstruse, which
		-- means that only part of the message (depending on the distance) will
		-- be understandable.
		abstruse = settings.get_number("voice_whisper_abstruse", 4),
		
		--- Everything within this range (inclusive) will not be understandable.
		incomprehensible = settings.get_number("voice_whisper_incomprehensible", 5),
		
		-- The type of these parameters.
		type = "whisper"
	}
}


--- Abstruses the given message. That means that parts of it will be blanked,
-- based on the rate.
--
-- @param message The message to abstruse.
-- @param rate The rate at which to abstruse the message, a value between
--             0 and 1, with 1 being everything abstrused.
-- @return The abstrused message.
function voice.abstruse(message, rate)
	local abstruse_message = ""
	
	for index = 1, string.len(message), 1 do
		local piece = string.sub(message, index, index)
		
		-- Only abstruse words, leave dots, quotes etc. in place.
		if string.find(piece, "%w") ~= nil then
			if voice.random(rate) then
				abstruse_message = abstruse_message .. "."
			else
				abstruse_message = abstruse_message .. piece
			end
		else
			abstruse_message = abstruse_message .. piece
		end
	end
	
	return abstruse_message
end

--- Activates the voice system.
function voice.activate()
	if voice.activate_automatically then
		voice.activate_internal()
	end
end

--- Activates the system, without checking the configuration.
function voice.activate_internal()
	if not voice.active then
		minetest.register_privilege(voice.global_privilege, {
			description = "The privilege needed to use the global chat.",
			give_to_singleplayer = true
		})
		
		--minetest.register_on_chat_message(voice.on_chat_message)
		
		voice.register_chatcommand("t", "talk", "Talk", voice.talk_parameters)
		voice.register_chatcommand("s", "shout", "Shout", voice.shout_parameters)
		voice.register_chatcommand("w", "whisper", "Whisper", voice.whisper_parameters)
		voice.register_global_chatcommand()
		
		voice.active = true
	end
end

--- Checks if the given distance is in the given range, considering
-- the line of sight.
--
-- @param distance The distance.
-- @param range The range.
-- @param line_of_sight If there is line of sight.
-- @return true if it is in range.
function voice.in_range(distance, range, line_of_sight)
	if line_of_sight then
		return distance <= range
	else
		return distance <= (range * voice.line_of_sight_mod)
	end
end

--- Invokes all registered message callbacks.
--
-- @param player The player that is sending the message.
-- @param type The type of the message.
-- @param message The message to be send.
-- @return true if the message should be suppressed, and the second return
--         value is the modified message.
function voice.invoke_message_callbacks(player, type, message)
	local suppress = false
	voice.message_callbacks:foreach(function(callback, index)
		local modified_suppress = nil
		local modified_message = nil
		
		modified_suppress, modified_message = callback(
			player,
			type,
			suppress,
			message)
		
		if modified_suppress ~= nil then
			suppress = modified_suppress
		end
		if modified_message ~= nil then
			message = modified_message
		end
	end)
	
	return suppress, message
end

--- Muffles the given messages, meaning replaces everything with dots.
--
-- @param message The message to muffle.
-- @return The muffled message.
function voice.muffle(message)
	-- Replace only words.
	return string.gsub(message, "%w", ".")
end

--- Callback for if a chat message is send.
--
-- @param name The name of the sending player.
-- @param message The message that is send.
-- @return true if the message has been handled and should not be send.
function voice.on_chat_message(name, message)
	local player = minetest.get_player_by_name(name)
	
	voice.speak(player, message, voice.talk_parameters)
	
	-- Do not send the message further, we've done that.
	return true
end

--- Gets a random chance based on the given rate.
--
-- @param rate The rate. A number between 0 and 1, with 1 being always true.
-- @return true if there is a chance.
function voice.random(rate)
	return (random.next_int(0, 100) / 100) <= rate
end

--- Registers a chat chommand.
--
-- @param short The short command.
-- @param long The long command.
-- @param description The description of the command.
-- @param parameters The parameters to use.
function voice.register_chatcommand(short, long, description, parameters)
	local command = {
		description = description,
		params = "<message>",
		func = function(player_name, message)
			local player = minetest.get_player_by_name(player_name)
			
			voice.speak(player, message, parameters)
			
			return true
		end
	}
	
	minetest.register_chatcommand(short, command)
	minetest.register_chatcommand(long, command)
end

--- Registers the chat command for global messaging.
function voice.register_global_chatcommand()
	minetest.register_privilege("voice_global", {
		description = "Allows the player to send global messages.",
		give_to_singleplayer = true
	})
	
	local command = {
		description = "Global",
		params = "<message>",
		privs = { [voice.global_privilege] = true },
		func = function(player_name, message)
			local suppress, message = voice.invoke_message_callbacks(
				minetest.get_player_by_name(player_name),
				voice.TYPE_GLOBAL,
				message)
			
			if suppress then
				return true
			end
			
			minetest.chat_send_all("<" .. player_name .. ">(Global): " .. message)
                        minetest.log("CHAT: <" .. player_name .. ">(Global): " .. message)
                        irc:say("<" .. player_name .. ">(Global): " .. message)
			
			return true
		end
	}
	
	minetest.register_chatcommand("g", command)
	minetest.register_chatcommand("global", command)
end

--- Registers a callback that is invoked for every message that is send.
--
-- @param callback The callback that is to be registered, a function that
--                 accepts the player (Player object), the type of the message
--                 (TYPE_* constants), if the message is going to be send and
--                 the message itself. The callback can return two values,
--                 the first, a boolean that is true if the message should
--                 be suppressed, and the second being a message to be sent
--                 instead. The last callback can determine if the message
--                 should actually be send or not.
function voice.register_on_message(callback)
	voice.message_callbacks:add(callback)
end

--- Speaks the given message.
--
-- @param speaking_player The speaking player, a Player Object.
-- @param message The message that is spoken.
-- @param parameters The speak parameters, like talk_parameters.
function voice.speak(speaking_player, message, parameters)
	local suppress, message = voice.invoke_message_callbacks(
		speaking_player,
		parameters.type,
		message)
	
	if suppress then
		return
	end
	
	local source_name = speaking_player:get_player_name()
	local source_pos = speaking_player:getpos()
        local short = string.sub(parameters.type, 1, 1)
	
	for index, player in ipairs(minetest.get_connected_players()) do
		local target_name = player:get_player_name()
		
		if source_name ~= target_name then
			local target_pos = player:getpos()
			local distance = mathutil.distance(source_pos, target_pos)
			
			-- Test now if we're even in range, minor optimization.
			if distance <= parameters.incomprehensible then
				-- TODO The y+1 thing is to emulate players height, might be wrong.
				local line_of_sight = minetest.line_of_sight({
					x = source_pos.x,
					y = source_pos.y + 1,
					z = source_pos.z
				}, {
					x = target_pos.x,
					y = target_pos.y + 1,
					z = target_pos.z
				})
				local short_type = string.sub(parameters.type, 1, 1)
                                short = short_type
				
				if voice.in_range(distance, parameters.understandable, line_of_sight) then
					minetest.chat_send_player(
						target_name,
						"<" .. source_name .. "> (" .. short_type .. ") " .. message)
				elseif voice.in_range(distance, parameters.abstruse, line_of_sight) then
					local rate = transform.linear(distance, parameters.understandable, parameters.abstruse)
					
					-- Here we have a random chance that the player name is muffeld.
					if voice.random(rate) then
						minetest.chat_send_player(
							target_name,
							"<" .. voice.muffle(source_name) .. ">(" .. short_type .. "): " ..  voice.abstruse(message, rate))
					else
						minetest.chat_send_player(
							target_name,
							"<" .. source_name .. ">(" .. short_type .. "): " .. voice.abstruse(message, rate))
					end
				elseif voice.in_range(distance, parameters.incomprehensible, line_of_sight) then
					minetest.chat_send_player(
					target_name,
					"<" .. voice.muffle(source_name) .. ">(" .. short_type .. "): " .. voice.muffle(message))
				end
			end
		end
	end
        minetest.log("CHAT: <" .. source_name .. "> (" .. short .. ") " .. message)
		if not minetest.get_player_privs(source_name).interact then
        --irc:say("<" .. source_name .. "> (" .. short .. ") " .. message)
		end
end