function panic(reason)
  print("PANIC: "..reason)
  -- This will trigger a restart, but not immediately
  node.restart()
end

info = function(msg)
  print("info "..msg)
end

local P = {}

local inter = require('inter')
local mq = require('mq')

local properties = {}

local function read_cfg(name, required)
  local filename = "cfg-"..name
  if not file.open(filename, "r") then
    if required then
      panic("Could not read configuration file: "..filename)
    else
      return nil
    end
  end
  local value = file.readline()
  file.close()
  if value == nil or #value == 0 then
    if required then
      panic("Empty configuration file: "..filename)
    else
      return nil
    end
  end
  return string.sub(value, 1, -2)
end

local function write_cfg(name, value)
  local filename = "cfg-"..name
  file.open(filename, "w+")
  local ok = file.writeline(value)
  file.flush()
  file.close()
  return ok
end

local function configure_wlan()
  local wlan_ssid = read_cfg("wlan-ssid", false)
  local wlan_password = read_cfg("wlan-password", false)

  if not wlan_ssid or not wlan_password then
    info("Missing SSID and/or password configuration, use 'wlan' to configure")
    return
  end

  info("Connecting to SSID: "..wlan_ssid)
  wifi.setmode(wifi.STATION)
  wifi.sta.config(wlan_ssid, wlan_password)
end

local function on_cmd(cmd, args)
  if not cmd then
    return
  end

  info("on_cmd: '"..cmd.."', #args="..tostring(table.getn(args)))
  for k, v in pairs(args) do
    info(k.."="..tostring(v))
  end

  if cmd == "reset" then
    print("ok reset")
    panic("Reset requested")
  elseif cmd == "wlan" then
    local ssid = args.ssid password = args.password

    local reconfigured = false
    if args.ssid then
      write_cfg("wlan-ssid", args.ssid)
    end
    if args.password then
      write_cfg("wlan-password", args.password)
    end
    if args.ssid and args.password then
      configure_wlan()
    end
    ssid, password, bssid_set, bssid = wifi.sta.getconfig()
    print("ok ssid="..(ssid or ''))
  elseif cmd == "network" then
    local ip = args.ip nm = args.netmask gw = args.gateway

    if args.ip then
      wifi.sta.setip({ip=ip, netmask=nm, gateway=gw})
    end

    ip, nm, gw = wifi.sta.getip()
    print("ok ip="..(ip or '').." netmask="..(nm or '').." gateway="..(gw or ''))
  elseif cmd == "set-property" then
    local id = args.id
    if not id then
      print("fail status=missing-id")
    else
      property = properties[id]

      local value_path = "property/"..id.."/value"
      local name_path = "property/"..id.."/name"
      local description_path = "property/"..id.."/description"

      if not property then
        info("new property: "..id)
        property = {}
        properties[id] = property
        mq.subscribe(name_path, function() info('message on '..path) end)
        mq.subscribe(description_path, function() info('message on '..path) end)
      end

      if args.value then
        mq.publish(value_path, args.value)
      end
      if args.name and property.name ~= args.name then
        info("publishing name")
        mq.publish(name_path, args.name)
        property.name = args.name
      end
      if args.description and property.description ~= args.description then
        info("publishing description")
        mq.publish(description_path, args.description)
        property.description = args.description
      end
    end
  elseif cmd == "publish" then
--    print("Publishing, topic="..tostring(cmd.topic)..", payload="..tostring(cmd.payload))
    ok, msg = mq.publish(cmd.topic, cmd.payload)
    if ok then
      print("ok status="..msg)
    else
      print("failed status="..msg)
    end
  else
    print("failed status=unknown-command")
  end
end

local function print_status()
  ip, nm, gw = wifi.sta.getip()
  print("status uptime="..tmr.time().." heap-left="..node.heap().." ip="..tostring(ip).." netmask="..tostring(nm).." gateway="..tostring(gw))
end

-- uart.setup(id, baud, databits, parity, stopbits, echo)
-- uart.setup(0, 115200, 8, 0, 1, 0)
-- uart.setup(0, 9600, 8, 0, 1, 0)

function P.main()
  local timers = {
    status = 0,
    inter = 1,
    mqtt = 2
  }

  configure_wlan(wlan_ssid, wlan_password)

  local mac = wifi.sta.getmac()
  local client_id = "esp8266-"..mac
  mq.init(timers.mqtt, mac, client_id)

  inter.init(on_cmd)

  tmr.alarm(timers.status, 10 * 1000, 1, print_status)

--  local majorVer, minorVer, devVer, chipId, flashId, flashSize, flashMode, flashSpeed, buildDate = node.info()
--  payload = '{"version": "'..majorVer..'.'..minorVer..'.'..devVer..'", "chipId":'..chipId..', "flashId":'..flashId..', "flashSize":'..flashSize..', "flashMode":'..flashMode..', "flashSpeed":'..flashSpeed
--
--  if buildDate then
--    payload = payload..', "buildDate": "'..buildDate..'"'
--  end
--
--  if node.info_versions then
--    major, minor, dev, buildDate, sdkVersion = node.info_versions()
--    payload = payload..'", versions": {"major": '..major..', "minor": '..minor..', "dev": '..dev..', "buildDate": "'..buildDate..'", "sdk": "'..sdkVersion..'"}'
--  end
--  payload = payload.."}"
--  P.publish("firmware", payload)

  info("init done")
end

return P