package hottisGy21

import (
  //"log"
  "fmt"
  "bytes"
  "encoding/base64"
  "encoding/binary"
  "udi/database"
)

type hottisGy21Values struct {
  Connected uint8
  Status uint8
  RawHumidity uint16
  RawTemperature uint16
}


func Parse(fPort int, _ []byte, frmPayload string, variables *map[string]database.VariableType, attributes *map[string]interface{}, _ *database.Device) error {
  if fPort != 2 {
    return fmt.Errorf("Unexpected fPort %d", fPort)
  }

  b, err := base64.StdEncoding.DecodeString(frmPayload)
  if err != nil {
    return fmt.Errorf("Unable to base64-decode payload: %v", err)
  }

  var values hottisGy21Values
  err = binary.Read(bytes.NewReader(b), binary.LittleEndian, &values)
  if err != nil {
    return fmt.Errorf("Unable to cast into struct: %v", err)
  }
  var temperature float32 = -46.85 + 175.72 * (float32(values.RawTemperature) / 65536.0)
  var humidity float32 = -6 + 125 * (float32(values.RawHumidity) / 65536.0);

  // log.Printf("CO2: %f, Temp: %f, Hum: %f, Status: %d", co2concentration, temperature, humidity, values.Status)

  (*variables)["Humidity"] = database.VariableType {
    Label: "Humidity",
    Variable: "Humidity",
    Unit: "%",
    Value: humidity,
  }
  (*variables)["Temperature"] = database.VariableType {
    Label: "Temperature",
    Variable: "Temperature",
    Unit: "°C",
    Value: temperature,
  }

  (*attributes)["Status"] = values.Status
  return nil
}