/**
 * Payload Decoder for The Things Network
 *
 * Copyright 2023 Milesight IoT
 *
 * @product WS203
 */
function Decoder(bytes, port) {
    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;

            // ℉
            // decoded.temperature = readInt16LE(bytes.slice(i, i + 2)) / 10 * 1.8 + 32;
            // i +=2;
        }
        // HUMIDITY
        else if (channel_id === 0x04 && channel_type === 0x68) {
            decoded.humidity = bytes[i] / 2;
            i += 1;
        }
        // OCCUPANCY
        else if (channel_id === 0x05 && channel_type === 0x00) {
            decoded.occupancy = bytes[i] === 0 ? "vacant" : "occupied";
            i += 1;
        }
        // TEMPERATURE WITH ABNORMAL
        else if (channel_id === 0x83 && channel_type === 0x67) {
            decoded.temperature = readInt16LE(bytes.slice(i, i + 2)) / 10;
            decoded.temperature_abnormal = bytes[i + 2] === 0 ? "normal" : "abnormal";
            i += 3;
        }
        // HISTORICAL DATA
        else if (channel_id === 0x20 && channel_type === 0xce) {
            var data = {};
            data.timestamp = readUInt32LE(bytes.slice(i, i + 4));
            var report_type = bytes[i + 4];
            data.report_type = ["temperature resume", "temperature threshold", "pir idle", "pir occupancy", "period"][report_type & 0x07];
            data.occupancy = bytes[i + 5] === 0 ? "vacant" : "occupied";
            data.temperature = readInt16LE(bytes.slice(i + 6, i + 8)) / 10;
            data.humidity = bytes[i + 8] / 2;
            i += 9;

            decoded.history = decoded.history || [];
            decoded.history.push(data);
        } 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 readUInt32LE(bytes) {
    var value = (bytes[3] << 24) + (bytes[2] << 16) + (bytes[1] << 8) + bytes[0];
    return (value & 0xffffffff) >>> 0;
}

function readInt32LE(bytes) {
    var ref = readUInt32LE(bytes);
    return ref > 0x7fffffff ? ref - 0x100000000 : ref;
}