#!/usr/bin/lua

function getConfig()

  local uci=require("uci")
  local cur=uci.cursor()
  local config="weathermon"

  web_url  = cur.get(config,"web","url")
  web_user = cur.get(config,"web","user")
  web_pass = cur.get(config,"web","password")
  web_devid = cur.get(config,"web","devid")

  web_iface = cur.get(config,"web","iface")

  if web_iface then
  
    command = '/sbin/ifconfig '..web_iface..' | grep \'\\<inet\\>\' | sed -n \'1p\' | tr -s \' \' | cut -d \' \' -f3 | cut -d \':\' -f2'
    f=io.popen(command,'r')
    ip_addr=f:read()
  
  end

  if not web_devid then
  
    if web_iface then
      io.input("/sys/class/net/"..web_iface.."/address")
    else
      io.input("/sys/class/net/eth0/address")
    end

    mac = io.read("*line")
    mac = mac:gsub(":","")
    mac = mac:upper()

    web_devid = mac

  end

  logging = cur.get(config,"logging","enabled") 

  serial_port = cur.get(config,"serial","port")
  serial_baud = cur.get(config,"serial","baud")

  input_file = cur.get(config,"input","file")
  input_exec = cur.get(config,"input","exec")
  alarm_exec = cur.get(config,"alarm","exec")

  if serial_port then

    command = "stty -F  "..serial_port.." "..serial_baud
    os.execute(command)

  end

  mqtt_host = cur.get(config,"mqtt","host")
  mqtt_port = cur.get(config,"mqtt","port")
  mqtt_id = cur.get(config,"mqtt","id")
  mqtt_topic = cur.get(config,"mqtt","topic")
  mqtt_alarm_topic = cur.get(config,"mqtt","alarm_topic")

  mqtt_user = cur.get(config,"mqtt","user")
  mqtt_passwd = cur.get(config,"mqtt","password")

  if mqtt_host and not mqtt_id then
    mqtt_id="weather-"..web_devid
  end

  if mqtt_host and not mqtt_port then
    mqtt_port = 1883
  end

  if mqtt_host and not mqtt_topic then
    mqtt_topic = 'weathermon/{dev}/{type}/{id}/{param}'
  end

  if mqtt_host and not mqtt_alarm_topic then
    mqtt_alarm_topic = 'alarm/{dev}/{type}/{id}'
  end

end

require "socket"

function sleep(sec)
  socket.select(nil, nil, sec)
end

function splitStr(str,char)

  local res = {}
  local idx = 1


  while str:len()>0 do
    pos = str:find(char); 
    if pos == nil then
      res[idx]=str
      str=""
    else
      res[idx]=str:sub(1,pos-1)
      idx=idx+1
      str=str:sub(pos+1)
    end
  end

  return res

end

function printLog(str)
  print(str)
  if logging=="on" then
    os.execute("logger -t weathermon "..str)
  end 
end

function submitValue(type,id,param,val)

  url = web_url.."?stype="..type.."&sid="..id.."&param="..param.."&value="..val

  command = "curl"

  if web_iface then
    command = command.." --interface "..ip_addr
  end

  if web_user then
    command = command.." -u "..web_user..":"..web_pass
  end

  command = command.." \""..url.."\""

  os.execute(command)
  print()

end

function processLine(str)

  msg=splitStr(line,':')
  msg_type=msg[1] or nil
  msg_body=msg[2] or nil
  if msg_type=="STATUS" then
    printLog("Status: "..msg_body)
  elseif msg_type=="ERROR" then
    printLog("Error: "..msg_body)  
  elseif msg_type=="SENSOR" then
    printLog("SENSOR: "..msg_body)  
    sens = splitStr(msg_body,",")
    sensor = {}
    idx = 1
    sensor_type = nil
    sensor_id = web_devid
    for i,rec in ipairs(sens) do
      recrd=splitStr(rec,'=')
      key=recrd[1] or nil
      value=recrd[2] or nil
      if value then
        if key=="TYPE" then
          sensor_type=value
        elseif key=="ID" then
          sensor_id=value
        else
          sensor[key]=value
        end
      end
    end
    for k,v in pairs(sensor) do
      printLog("Type = "..sensor_type..", ID = "..sensor_id..", Param = "..k..", Value = "..v)
      submitValue(sensor_type,sensor_id,k,v)
      if mqtt_client then
        mqtt_path=string.gsub(mqtt_topic,"{(.-)}", 
          function (name) 
            if name=="dev" then
              return web_devid
            elseif name=="type" then
              return sensor_type
            elseif name=="id" then
              return sensor_id
            elseif name=="param" then
              return k
            else
              return '{'..name..'}'
            end      
          end)
        mqtt_client:publish(mqtt_path,v)
      end  
    end
  elseif msg_type=="ALARM" then
    printLog("ALARM: "..msg_body)  
    sens = splitStr(msg_body,",")
    sensor = {}
    idx = 1
    sensor_type = nil
    sensor_id = web_devid
    mqtt_param = {}
    for i,rec in ipairs(sens) do
      recrd=splitStr(rec,'=')
      key=recrd[1] or nil
      value=recrd[2] or nil
      if value then
        if key=="TYPE" then
          alarm_type=value
        elseif key=="ID" then
          alarm_id=value
        end
      end
    end
    if mqtt_client then
      mqtt_path=string.gsub(mqtt_alarm_topic,"{(.-)}", 
        function (name) 
          if name=="dev" then
            return web_devid
          elseif name=="type" then
            return sensor_type
          elseif name=="id" then
            return sensor_id
          else
            return '{'..name..'}'
          end      
        end)
      mqtt_client:publish(mqtt_path,msg_body)
    end
    if alarm_exec then
      command=alarm_exec..
        " \""..string.gsub(alarm_type,"\"","\\\"")..
        "\" \""..string.gsub(alarm_id,"\"","\\\"")..
        "\" \""..string.gsub(msg_body,"\"","\\\"").."\""
      os.execute(command)
    end
  end

end

getConfig()

if mqtt_host then
  MQTT = require "paho.mqtt"
  mqtt_client = MQTT.client.create(mqtt_host, mqtt_port)
  if mqtt_user then
    mqtt_client:auth(mqtt_user, mqtt_passwd)
  end
  mqtt_client:connect(mqtt_id)
  json = require( "json" )
end

if serial_port then
  serialin=io.open(serial_port,"r")
elseif input_file == "-" then
  serialin=io.stdin;
elseif input_file then
  serialin=io.open(input_file,"r")
elseif input_exec then
  serialin=io.popen(input_exec,"r")
else
  printLog("No input selected")
  return
end  
while 1 do
  line=serialin:read()
  print(line)
  processLine(line)
end