1 files changed, 86 insertions, 0 deletions
diff --git a/wakeup.lua b/wakeup.lua
new file mode 100644
index 0000000..9239fe1
--- /dev/null
+++ b/wakeup.lua
@@ -0,0 +1,86 @@
+local wakeup = require("+wakeup")
+
+
+--- Builds and returns a Wake-on-LAN magic packet for [[mac]] address.
+local
+function magic_packet (mac)
+	local data = ""
+	for octet in mac:gmatch("%x%x") do
+		data = data .. string.char(tonumber(octet, 16))
+	end
+	if #data ~= 6 then
+		error(string.format("Invalid MAC\t%q", mac), 2)
+	end
+	return string.char(0xff):rep(6) .. data:rep(16)
+end
+
+
+function wakeup:open ()
+	self.udp = net.createUDPSocket()
+end
+
+
+function wakeup:close ()
+	if self.udp then
+		self.udp:close()
+	end
+end
+
+
+--- Creates a new counter that has :up() method that returns true until it gets called N [[times]]. Then it returns only
+--- false.
+local
+function new_counter (times)
+	return {
+		count = 0,
+		times = times,
+		up = function (self)
+			self.count = self.count + 1
+			return self.count <= self.times
+		end,
+	}
+end
+
+
+--- Begins to send Wake-on-LAN magic packets to the broadcast [[.addr]] for selected [[.mac]]. Packets are sent several
+--- [[times]] each separated by [[interval]]. Callback is called [[after]] all packets are sent.
+function wakeup:sendout (interval, times, after)
+	self:open()
+	local count = new_counter(times)
+	return tmr.create():alarm(interval, tmr.ALARM_SEMI, function (timer)
+		if count:up() then
+			print("Waking up", self.mac, self.addr)
+			self.udp:send(self.port, self.addr, self.data)
+			timer:start()
+		else
+			timer:unregister()
+			self:close()
+			after()
+		end
+	end)
+end
+
+
+function wakeup:init ()
+	gpio.write(4, gpio.HIGH)
+	gpio.mode(4, gpio.OUTPUT)
+	self.data = magic_packet(self.mac)
+
+	wifi.eventmon.register(wifi.eventmon.STA_GOT_IP, function ()
+		gpio.write(4, gpio.LOW)
+
+		self:sendout(500, 5, function ()
+			wifi.setmode(wifi.NULLMODE, false)
+			gpio.write(4, gpio.HIGH)
+		end)
+	end)
+end
+
+
+function wakeup:run ()
+	wifi.setmode(wifi.STATION, false)
+	wifi.sta.connect()
+end
+
+
+return wakeup