/**
 * Payload Decoder for Milesight Network Server
 *
 * Copyright 2023 Milesight IoT
 *
 * @product WT101
 */
function Decode(fPort, bytes) {
    return milesight(bytes);
}

function milesight(bytes) {
    var decoded = {};

    for (var i = 0; i < bytes.length; ) {
        var channel_id = bytes[i++];
        var channel_type = bytes[i++];
        // BATTERY
        if (channel_id === 0x01 && channel_type === 0x75) {
            decoded.battery = bytes[i];
            i += 1;
        }
        // TEMPERATURE
        else if (channel_id === 0x03 && channel_type === 0x67) {
            decoded.temperature = readInt16LE(bytes.slice(i, i + 2)) / 10;
            i += 2;
        }
        // TEMPERATURE TARGET
        else if (channel_id === 0x04 && channel_type === 0x67) {
            decoded.temperature_target = readInt16LE(bytes.slice(i, i + 2)) / 10;
            i += 2;
        }
        // VALVE OPENING
        else if (channel_id === 0x05 && channel_type === 0x92) {
            decoded.valve_opening = readUInt8(bytes[i]);
            i += 1;
        }
        // INSTALLATION STATUS
        else if (channel_id === 0x06 && channel_type === 0x00) {
            decoded.tamper_status = bytes[i] === 0 ? "installed" : "uninstalled";
            i += 1;
        }
        // FEENSTRATION STATUS
        else if (channel_id === 0x07 && channel_type === 0x00) {
            decoded.window_detection = bytes[i] === 0 ? "normal" : "open";
            i += 1;
        }
        // MOTOR STORKE CALIBRATION STATUS
        else if (channel_id === 0x08 && channel_type === 0xe5) {
            decoded.motor_calibration_result = readMotorCalibration(bytes[i]);
            i += 1;
        }
        // MOTOR STROKE
        else if (channel_id === 0x09 && channel_type === 0x90) {
            decoded.motor_storke = readUInt16LE(bytes.slice(i, i + 2));
            i += 2;
        }
        // FROST PROTECTION
        else if (channel_id === 0x0a && channel_type === 0x00) {
            decoded.freeze_protection = bytes[i] === 0 ? "normal" : "triggered";
            i += 1;
        }
        // MOTOR CURRENT POSTION
        else if (channel_id === 0x0b && channel_type === 0x90) {
            decoded.motor_position = readUInt16LE(bytes.slice(i, i + 2));
            i += 2;
        } else {
            break;
        }
    }

    return decoded;
}

function readUInt8(bytes) {
    return bytes & 0xff;
}

function readInt8(bytes) {
    var ref = readUInt8(bytes);
    return ref > 0x7f ? ref - 0x100 : ref;
}

function readUInt16LE(bytes) {
    var value = (bytes[1] << 8) + bytes[0];
    return value & 0xffff;
}

function readInt16LE(bytes) {
    var ref = readUInt16LE(bytes);
    return ref > 0x7fff ? ref - 0x10000 : ref;
}

function readMotorCalibration(type) {
    switch (type) {
        case 0x00:
            return "success";
        case 0x01:
            return "fail: out of range";
        case 0x02:
            return "fail: uninstalled";
        case 0x03:
            return "calibration cleared";
        case 0x04:
            return "temperature control disabled";
        default:
            return "unknown";
    }
}