-- ***************************************************************************
-- Yeelink Updata Libiary Version 0.1.2 r1
--
-- Written by Martin
-- but based on a script of zhouxu_o from bbs.nodemcu.com
--
-- MIT license, http://opensource.org/licenses/MIT
-- ***************************************************************************
--==========================Module Part======================

local moduleName = ...
local M = {}
_G[moduleName] = M
--=========================Local Args=======================
local dns = "0.0.0.0"

local device = ""
local sensor = ""
local apikey = ""

--================================
local debug = true --<<<<<<<<<<<<< Don't forget to "false" it before using
--================================
local sk = net.createConnection(net.TCP, 0)

local datapoint = 0


--====DNS the yeelink ip advance(in order to save RAM)=====

if wifi.sta.getip() == nil then
    print("Please Connect WIFI First")
    local wifiTimer = tmr.create()
    wifiTimer:alarm(1000, tmr.ALARM_AUTO,function ()
        if wifi.sta.getip() ~= nil then
            wifiTimer:stop()
            sk:dns("api.yeelink.net",function(_,ip)
            dns=ip
            print("DNS YEELINK OK... IP: "..dns)
            end)
        end
    end)
end

sk:dns("api.yeelink.net",function(conn, ip) -- luacheck: no unused
  dns = ip
  print("DNS YEELINK OK... IP: "..dns)
end)

--========Set the init function===========
--device->number
--sensor->number
-- apikey must be -> string <-
-- e.g. xxx.init(00000,00000,"123j12b3jkb12k4b23bv54i2b5b3o4")
--========================================
function M.init(_device, _sensor, _apikey)
    device = tostring(_device)
    sensor = tostring(_sensor)
    apikey = _apikey
    if dns == "0.0.0.0" then
      tmr.create():alarm(5000,tmr.ALARM_AUTO,function ()
        if dns == "0.0.0.0" then
          print("Waiting for DNS...")
        end
      end)
    return false
    else
        return dns
    end
end
--========Check the DNS Status===========
--if DNS success, return the address(string)
--if DNS fail(or processing), return nil
--
--
--========================================
function  M.getDNS()

    if dns == "0.0.0.0" then
        return nil
    else
        return dns
    end

end

--=====Update to Yeelink Sever(At least 10s per sencods))=====
--  datapoint->number
--
--e.g. xxx.update(233.333)
--============================================================
function M.update(_datapoint)

    datapoint = tostring(_datapoint)

    sk:on("connection", function()

        print("connect OK...")


    local a=[[{"value":]]
    local b=[[}]]

    local st=a..datapoint..b

        sk:send("POST /v1.0/device/"..device.."/sensor/"..sensor.."/datapoints HTTP/1.1\r\n"
.."Host: www.yeelink.net\r\n"
.."Content-Length: "..string.len(st).."\r\n"--the length of json is important
.."Content-Type: application/x-www-form-urlencoded\r\n"
.."U-ApiKey:"..apikey.."\r\n"
.."Cache-Control: no-cache\r\n\r\n"
..st.."\r\n" )

    end)

    sk:on("receive", function(conn, content) -- luacheck: no unused

    if debug then
    print("\r\n"..content.."\r\n")
    else
    print("Date Receive")
    end

    end)

    sk:connect(80,dns)


end
--================end==========================
return M