vc-kirby-app/app/src/main/java/com/logitech/vc/kirbytest/DecoderIaq.kt

package com.logitech.vc.kirbytest

import com.google.gson.annotations.SerializedName
import kotlin.math.roundToInt


object DecoderIaq {
    private const val INVALID_CO2 = 16383
    private const val INVALID_VOC = 2047
    private const val INVALID_HUMIDITY = 1023
    private const val INVALID_TEMPERATURE = 2047
    private const val INVALID_PRESSURE = 65535
    private const val INVALID_OCCUPANCY = 3
    private const val INVALID_PM25 = 1023
    private const val INVALID_PM10 = 1023

    private val supportedMessageTypes = listOf<Number>(0, 1, 5)

    fun parseMeasurement(input: String): Uplink? {

        val inputBytes = hexStringToByteArray(input)
        val msgType = inputBytes[0].toInt() and 0xFF ushr 4

        if (!supportedMessageTypes.contains(msgType)) {
            return null
        }

        if (msgType < 3) {
            return parseIaq(msgType, inputBytes)
        } else if (msgType == 5) {
            return parseDeviceStatus(msgType, inputBytes)
        }

        return null
    }

    private fun parseDeviceStatus(msgType: Number, inputBytes: ByteArray): DeviceStatus {
        val status = DeviceStatus(msgType = msgType)

        val fwMajor = parseUnsignedIntFromBytes(inputBytes, 4, 8)
        val fwMinor = parseUnsignedIntFromBytes(inputBytes, 12, 8)
        val fwPatch = parseUnsignedIntFromBytes(inputBytes, 20, 8)
        val fwTweak = parseUnsignedIntFromBytes(inputBytes, 28, 8)

        status.firmware = "$fwMajor.$fwMinor.$fwPatch"
        if(fwTweak > 0u) {
            status.firmware += "-$fwTweak"
        }

        status.operationMode = parseUnsignedIntFromBytes(inputBytes, 36, 4).toInt()
        val batteryVoltage =  parseUnsignedIntFromBytes(inputBytes, 40, 16).toInt()
        if (batteryVoltage == 0) {
           status.usbPowered = true
        } else {
            status.batteryVoltage = batteryVoltage / 1000f
        }


        if (inputBytes.size > 7) {
            val errors =  inputBytes[7].toInt()
            val errorCo2 = (errors shr 0) and 1
            val errorVoc =  (errors shr 1) and 1
            val errorPm =  (errors shr 2) and 1
            val errorRadar = (errors shr 3) and 1
            val errorTemp =  (errors shr 4) and 1

            status.errorCo2 = errorCo2 == 1
            status.errorVoc = errorVoc == 1
            status.errorPm = errorPm == 1
            status.errorRadar = errorRadar == 1
            status.errorTemp = errorTemp == 1
        }


        return status
    }


    private fun parseIaq(msgType: Number, inputBytes: ByteArray): Measurement {
        val measurement = Measurement()
        measurement.msgType = msgType

        val co2 = parseUnsignedInt(inputBytes, 0, 3) ushr 6 and INVALID_CO2
        measurement.co2 = if (co2 == INVALID_CO2) null else co2

        val voc = parseUnsignedInt(inputBytes, 2, 4) ushr 3 and INVALID_VOC
        measurement.voc = if (co2 == INVALID_VOC) null else voc

        val humidity =
            parseUnsignedInt(inputBytes, 3, 5) ushr 1 and INVALID_HUMIDITY
        measurement.humidity = if (humidity == INVALID_HUMIDITY) null else humidity / 10

        val temperature =
            parseUnsignedInt(inputBytes, 4, 7) ushr 6 and INVALID_TEMPERATURE
        measurement.temperature =
            if (temperature == INVALID_TEMPERATURE) null else ((temperature / 10.0 - 40) * 10.0).roundToInt() / 10.0

        val pressure =
            parseUnsignedInt(inputBytes, 6, 9) ushr 6 and INVALID_PRESSURE
        measurement.pressure =
            if (pressure == INVALID_PRESSURE) null else (30000 + 19000.0 * pressure / 13107).roundToInt()

        val occupancy =
            parseUnsignedInt(inputBytes, 8, 9) ushr 4 and INVALID_OCCUPANCY
        measurement.occupancy = if (occupancy == INVALID_OCCUPANCY) null else occupancy

        if (msgType == 0) {
            val pm25 =
                parseUnsignedInt(inputBytes, 8, 10) ushr 2 and INVALID_PM25
            measurement.pm25 = if (pm25 == INVALID_PM25) null else pm25

            val pm10 = parseUnsignedInt(inputBytes, 9, 11) and INVALID_PM10
            measurement.pm10 = if (pm10 == INVALID_PM10) null else pm10
        }
        return measurement
    }


    interface Uplink {
        var deviceId: String?
        var msgType: Number?
    }

    data class Measurement(
        @SerializedName("bleAddress")
        override var deviceId: String? = null,
        override var msgType: Number? = null,
        var co2: Number? = null,
        var voc: Number? = null,
        var humidity: Number? = null,
        var temperature: Number? = null,
        var pressure: Number? = null,
        var occupancy: Number? = null,
        var pm25: Number? = null,
        var pm10: Number? = null
    ) : Uplink {
        override fun toString(): String {
            return "M{" +
                    "type=" + msgType +
                    ", co2=" + co2 +
                    ", voc=" + voc +
                    ", hum=" + humidity +
                    ", temp=" + temperature +
                    ", press=" + pressure +
                    ", pm25=" + pm25 +
                    ", pm10=" + pm10 +
                    ", occ=" + occupancy +
                    '}'
        }
    }

    data class DeviceStatus(
        @SerializedName("bleAddress")
        override var deviceId: String? = null,
        override var msgType: Number? = null,
        var firmware: String? = null,
        var operationMode: Number? = null,
        var batteryVoltage: Number? = null,
        var usbPowered: Boolean = false,
        var errorCo2: Boolean = false,
        var errorVoc: Boolean = false,
        var errorPm: Boolean = false,
        var errorRadar: Boolean = false,
        var errorTemp: Boolean = false,
    ) : Uplink {
        override fun toString(): String {
            return "S{" +
                    "type=" + msgType +
                    ", fw=" + firmware +
                    ", op=" + operationMode +
                    ", usb=" + usbPowered +
                    ", batt=" + batteryVoltage +
                    ", errTemp=" + errorTemp +
                    ", errCo2=" + errorCo2 +
                    ", errVoc=" + errorVoc +
                    ", errPm=" + errorPm +
                    ", errRad=" + errorRadar +
                    '}'
        }
    }
}