From 03e7b0511a6515b1ff20db9da68e699ffa77018c Mon Sep 17 00:00:00 2001
From: Alessandro <4512372+Ale32bit@users.noreply.github.com>
Date: Sat, 26 Jan 2019 01:07:24 +0100
Subject: [PATCH] Create node.lua

---
 node.lua | 205 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 205 insertions(+)
 create mode 100644 node.lua

diff --git a/node.lua b/node.lua
new file mode 100644
index 0000000..89342c0
--- /dev/null
+++ b/node.lua
@@ -0,0 +1,205 @@
+-- Node.lua
+-- By Ale32bit
+
+-- https://git.ale32bit.me/Ale32bit/Node.lua
+
+-- MIT License
+-- Copyright (c) 2019 Alessandro "Ale32bit"
+
+-- Full license
+-- https://git.ale32bit.me/Ale32bit/Node.lua/src/branch/master/LICENSE
+
+local node = {}
+
+-- utils
+
+local function genHex()
+	local rand = math.floor(math.random() * math.floor(16^8))
+	
+	return rand
+end
+
+-- coroutine manager
+
+local procs = {}
+
+local function spawn(func)
+	local id = #procs + 1
+	procs[id] = {
+		kill = false,
+		thread = coroutine.create(func),
+		filter = nil,
+	}
+	return id
+end
+
+local function kill(pid)
+	procs[pid].kill = true
+end
+
+-- Node functions
+
+function node.on(event, func)
+	assert(type(event) == "string", "bad argument #1 (expected string, got ".. type(func) ..")")
+	assert(type(func) == "function", "bad argument #2 (expected function, got ".. type(func) ..")")
+	local listener = {}
+	listener.event = event
+	listener.func = func
+	listener.id = genHex()
+	listener.run = true
+	listener.stopped = false
+	listener.pid = spawn(function()
+		while listener.run do
+			local ev = {os.pullEvent(event)}
+			listener.func(unpack(ev, 2))
+		end
+	end)
+	
+	listener = setmetatable(listener, {
+		__tostring = function()
+			return string.format("Listener 0x%x [%s] (%s)", listener.id, event, string.match(tostring(func),"%w+$"))
+		end,
+	})
+	
+	return listener
+end
+
+function node.removeListener(listener)
+	assert(type(listener) == "table", "bad argument #1 (expected listener, got ".. type(listener) ..")")
+	local id = listener.id
+	assert(id, "bad argument #1 (expected listener, got ".. type(listener) ..")")
+	
+	if listener.stopped then
+		return false
+	end
+	
+	listener.run = false
+	listener.stopped = true
+	kill(listener.pid)
+	return true
+end
+
+function node.setInterval(func, s, ...)
+	assert(type(func) == "function", "bad argument #1 (expected function, got ".. type(func) ..")")
+	s = s or 0
+	assert(type(s) == "number", "bad argument #2 (expected number, got ".. type(s) ..")")
+	local interval = {}
+	interval.interval = s
+	interval.func = func
+	interval.args = {...}
+	interval.id = genHex()
+	interval.run = true
+	interval.stopped = false
+	interval.pid = spawn(function()
+		while interval.run do
+			local timer = os.startTimer(interval.interval)
+			local _, p = os.pullEvent("timer")
+			if p == timer then
+				spawn(function()
+					interval.func(unpack(interval.args))
+				end)
+			end
+		end
+	end)
+	
+	interval = setmetatable(interval, {
+		__tostring = function()
+			return string.format("Interval 0x%x [%s]s (%s)", interval.id, s, string.match(tostring(func),"%w+$"))
+		end,
+	})
+	
+	return interval
+end
+
+function node.clearInterval(interval)
+	assert(type(interval) == "table", "bad argument #1 (expected interval, got ".. type(interval) ..")")
+	local id = interval.id
+	assert(id, "bad argument #1 (expected interval, got ".. type(interval) ..")")
+	
+	if interval.stopped then
+		return false
+	end
+	
+	interval.run = false
+	interval.stopped = true
+	kill(interval.pid)
+	return true
+end
+
+function node.setTimeout(func, s, ...)
+	assert(type(func) == "function", "bad argument #1 (expected function, got ".. type(func) ..")")
+	s = s or 0
+	assert(type(s) == "number", "bad argument #2 (expected number, got ".. type(s) ..")")
+	local interval = {}
+	interval.timeout = s
+	interval.func = func
+	interval.args = {...}
+	interval.id = genHex()
+	interval.stopped = false
+	interval.pid = spawn(function()
+		local timer = os.startTimer(interval.timeout)
+		local _, p = os.pullEvent("timer")
+		if p == timer then
+			spawn(function()
+				interval.func(unpack(interval.args))
+				interval.stopped = true
+			end)
+		end
+	end)
+	
+	interval = setmetatable(interval, {
+		__tostring = function()
+			return string.format("Timeout 0x%x [%s]s (%s)", interval.id, s, string.match(tostring(func),"%w+$"))
+		end,
+	})
+	
+	return interval
+end
+
+function node.clearTimeout(interval)
+	assert(type(interval) == "table", "bad argument #1 (expected timeout, got ".. type(interval) ..")")
+	local id = interval.id
+	assert(id, "bad argument #1 (expected timeout, got ".. type(interval) ..")")
+	
+	if interval.stopped then
+		return false
+	end
+	
+	interval.stopped = true
+	kill(interval.pid)
+	return true
+end
+
+function node.init()
+	while (function() 
+		local c = 0
+		for k,v in pairs(procs) do
+			c = c+1
+		end
+		
+		return c > 0
+	end)() do
+		local event = {coroutine.yield()}
+		for pid, proc in pairs(procs) do
+			if proc.kill then -- remove process if killed
+				procs[pid] = nil
+			else
+				if proc.filter == nil or proc.filter == event[1] or event[1] == "terminate" then
+					local ok, par = coroutine.resume( proc.thread, unpack(event))
+					if not ok then
+						error(par, 0)
+						break
+					else
+						procs[pid].filter = par
+					end
+				end
+				if coroutine.status(proc.thread) == "dead" then
+					procs[pid] = nil
+				end
+			end
+		end
+	end
+end
+
+
+return node