mcdiscordbot/MinecraftDiscordBot/ClientScript.lua

local secretToken = "$TOKEN"
local connectionUri = "$HOST"
local waitSeconds = 5
-- https://github.com/cc-tweaked/CC-Tweaked/blob/9cf70b10effeeed23e0e9c537bbbe0b2ff0d1a0f/src/main/java/dan200/computercraft/core/apis/http/options/AddressRule.java#L29
-- Chunk size must be less than packet size (type reply, success, chunkids, content: chunk) 16 kb for buffer
local maxMessageSize = (128 - 16) * 1024

local function chunkString(value, chunkSize)
	if not chunkSize then chunkSize = maxMessageSize end
	local length = value:len()
	local total = math.ceil(length / chunkSize)
	local chunks = {}
	if length == 0 then
		total = 1
		chunks[1] = ""
	else
		local i = 1
		for i=1,total do
			local pos = 1 + ((i - 1) * chunkSize)
			chunks[i] = value:sub(pos, pos + chunkSize - 1)
		end
	end
	return total, chunks
end

local function sendJson(socket, message)
	return socket.send(textutils.serializeJSON(message))
end

local function sendResponse(socket, id, result, success)
	if success == nil then success = 0 end

	local total, chunks = chunkString(result)
	for i, chunk in pairs(chunks) do
		sendJson(socket, { type = "reply", id = id, result = chunk, chunk = i, total = total, success = success })
	end
end

-- error: no rs system
-- return rssystem rs
local function getPeripheral(name)
	local dev = peripheral.find(name)
	if not dev then error({message = "No peripheral '"..name.."' attached to the computer!"}) end
	return dev
end

local function runRsCommand(params)
	local script, reason = loadstring("local rs = peripheral.find(\"rsBridge\") if not rs then error({message = \"RS Bridge is not attached!\"}) end return rs."..params.command)
	if not script then error({message = "Invalid command: "..reason.."!"}) end
	local result = table.pack(pcall(script))
	local success = result[1]
	if not success then error({message = "Command execution failed: "..result[2].."!"}) end

	local retvals = {}
	retvals.n = result.n - 1
	for i=1,retvals.n do retvals[tostring(i)] = result[i + 1] end
	return textutils.serializeJSON(retvals)
end

local function getPeripheralInfo(side)
	return {type = peripheral.getType(side), methods = peripheral.getMethods(side), side = side}
end

local function getPeripheralList()
	local pers = {}
	for i,side in pairs(peripheral.getNames()) do pers[side] = getPeripheralInfo(side) end
	return pers
end

-- error: any error during execution
-- return string result
local function getResponse(parsed)
	if parsed.method == "energyusage" then
		return tostring(getPeripheral("rsBridge").getEnergyUsage())
	elseif parsed.method == "energystorage" then
		return tostring(getPeripheral("rsBridge").getEnergyStorage())
	elseif parsed.method == "listitems" then
		return textutils.serializeJSON(getPeripheral("rsBridge").listItems())
	elseif parsed.method == "listfluids" then
		return textutils.serializeJSON(getPeripheral("rsBridge").listFluids())
	elseif parsed.method == "craft" then
		return tostring(getPeripheral("rsBridge").craftItem(parsed.params))
	elseif parsed.method == "getitem" then
		local item = getPeripheral("rsBridge").getItem(parsed.params)
		if not item then error({message = "Requested item not found!"}) end
		return textutils.serializeJSON(item)
	elseif parsed.method == "command" then
		return runRsCommand(parsed.params)
	elseif parsed.method == "peripherals" then
		return textutils.serializeJSON(getPeripheralList())
	elseif parsed.method == "getonline" then
		return textutils.serializeJSON(getPeripheral("playerDetector").getOnlinePlayers())
	elseif parsed.method == "whereis" then
		local pos = getPeripheral("playerDetector").getPlayerPos(parsed.params.username)
		if not pos then return "null" end
		return textutils.serializeJSON(pos)
	elseif parsed.method == "send" then
		if not parsed.params.username then
			getPeripheral("chatBox").sendMessage(parsed.params.message, parsed.params.prefix)
		else
			getPeripheral("chatBox").sendMessageToPlayer(parsed.params.message, parsed.params.username, parsed.params.prefix)
		end
		return "true"
	end

	error({message = "No message handler for method: "..parsed.method.."!"})
end

local function logJSON(json, prefix)
	if not prefix then prefix = "" end
	for k,v in pairs(json) do
		local key = prefix..k
		if type(v) == "table" then
			logJSON(v, key..".")
		else
			print(key, "=", textutils.serializeJSON(v))
		end
	end
end

-- return bool success
local function handleMessage(socket, message)
	local parsed, reason = textutils.unserializeJSON(message)
	if not parsed then
		print("Received message:", message)
		printError("Message could not be parsed:", reason)
		return false
	end

	pcall(function() print("Received JSON:") logJSON(parsed) end)

	if parsed.type == "request" then
		local success, result = pcall(function() return getResponse(parsed) end)
		if not success then
			if not result.message then
				sendResponse(socket, parsed.id, result, 2)
			else
				sendResponse(socket, parsed.id, result.message, 1)
			end
		else
			sendResponse(socket, parsed.id, result, 0)
		end
		return true
	end

	printError("Invalid message type:", parsed.type)
	return false
end

local function responder(socket)
	while true do
		local message, binary = socket.receive()
		if not not message and not binary then
			if message == "outdated" then
				printError("Current script is outdated! Please update from the host!")
				return
			end
			handleMessage(socket, message)
		end
	end
end

local function termWaiter()
	os.pullEvent("terminate")
end

local function chatEventListener(socket)
	while true do
		event, username, message, uuid, hidden = os.pullEvent("chat")
		sendJson(socket, {type = "chat", username = username, message = message, uuid = uuid, hidden = hidden})
		print("Chat event relayed!")
	end
end

local function peripheralDetachEventListener(socket)
	while true do
		event, side = os.pullEvent("peripheral_detach")
		sendJson(socket, {type = "peripheral_detach", side = side})
		print("Peripheral was detached!")
	end
end

local function peripheralAttachEventListener(socket)
	while true do
		event, side = os.pullEvent("peripheral")
		sendJson(socket, {type = "peripheral", peripheral = getPeripheralInfo(side) })
		print("Peripheral was attached!")
	end
end

local function listAsSet(list)
	local asSet = {}
	for i,elem in pairs(list) do asSet[elem] = true end
	return asSet
end

local function joinSets(a, b)
	local joined = {}
	for elem,exists in pairs(a) do if exists then joined[elem] = true end end
	for elem,exists in pairs(b) do if exists then joined[elem] = true end end
	return joined
end

local function playerStatusEventListener(socket)
	local players = {}
	while true do
		local pd = peripheral.find("playerDetector")
		if not not pd then
			players = listAsSet(pd.getOnlinePlayers())
			break
		end
		printError("playerDetector not connected!")
		sleep(5)
	end
	while true do
		local pd = peripheral.find("playerDetector")
		if not not pd then
			local newPlayers = listAsSet(pd.getOnlinePlayers())
			for player,_ in pairs(joinSets(players, newPlayers)) do
				if players[player] and (not newPlayers[player]) then
					sendJson(socket, {type = "playerstatus", player = player, status = false})
				elseif (not players[player]) and newPlayers[player] then
					sendJson(socket, {type = "playerstatus", player = player, status = true})
				end
			end
			players = newPlayers
		end
		sleep(1)
	end
end

local function eventListeners(socket)
	parallel.waitForAny(
		termWaiter,
		function() chatEventListener(socket) end,
		function() playerStatusEventListener(socket) end,
		function() peripheralDetachEventListener(socket) end,
		function() peripheralAttachEventListener(socket) end
	)
end

local function socketClient()
	print("Connecting to the socket server at "..connectionUri.."...")
	local socket, reason = http.websocket(connectionUri)
	if not socket then error("Socket server could not be reached: "..reason) end
	print("Connection successful!")

	socket.send("login="..secretToken)
	parallel.waitForAny(
		function() responder(socket) end,
		function() eventListeners(socket) end
	)
	socket.close()
end

local function main()
	while true do
		local status, error = pcall(socketClient)
		if status then break end
		printError("An uncaught exception was raised:", error)
		printError("Restarting in", waitSeconds, "seconds...")
		sleep(waitSeconds)
	end
end

local oldPullEvent = os.pullEvent
os.pullEvent = os.pullEventRaw
pcall(main)
os.pullEvent = oldPullEvent