SenseCAP_LoRaWAN_V4_Decoder_For_Datacake.js

function Decoder(bytes, port) {
    var bytesString = bytes2HexString(bytes).toLocaleUpperCase();
    var datacakeFields = []
    var measurement = messageAnalyzed(bytesString);
    datacakeFields = measurement;
    return datacakeFields;
}

function messageAnalyzed(messageValue) {
    try {
        var frames = unpack(messageValue);
        var measurementResultArray = [];
        for (var i = 0; i < frames.length; i++) {
            var item = frames[i];
            var dataId = item.dataId;
            var dataValue = item.dataValue;
            var measurementArray = deserialize(dataId, dataValue);
            measurementResultArray = measurementResultArray.concat(measurementArray);
        }
        return measurementResultArray;
    } catch (e) {
        return e.toString();
    }
}

function unpack(messageValue) {
    var frameArray = [];

    for (var i = 0; i < messageValue.length; i++) {
        var remainMessage = messageValue;
        var dataId = remainMessage.substring(0, 2);
        var dataValue;
        var dataObj = {};
        switch (dataId) {
            case '01':
                dataValue = remainMessage.substring(2, 94);
                messageValue = remainMessage.substring(94);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '02':
                dataValue = remainMessage.substring(2, 32);
                messageValue = remainMessage.substring(32);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '03':
                break;
            case '04':
                dataValue = remainMessage.substring(2, 20);
                messageValue = remainMessage.substring(20);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '05':
                dataValue = remainMessage.substring(2, 10);
                messageValue = remainMessage.substring(10);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '06':
                dataValue = remainMessage.substring(2, 44);
                messageValue = remainMessage.substring(44);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '07':
                dataValue = remainMessage.substring(2, 76);
                messageValue = remainMessage.substring(76);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '08':
                dataValue = remainMessage.substring(2, 70);
                messageValue = remainMessage.substring(70);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '09':
                dataValue = remainMessage.substring(2, 36);
                messageValue = remainMessage.substring(36);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '0A':
                dataValue = remainMessage.substring(2, 68);
                messageValue = remainMessage.substring(68);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '0B':
                dataValue = remainMessage.substring(2, 62);
                messageValue = remainMessage.substring(62);
                dataObj = {
                    'dataId': dataId, 'dataValue': dataValue
                };
                break;
            case '0C':
                break;
            default:
                dataValue = '';
                break;
        }
        if (dataValue.length < 2) {
            break;
        }
        frameArray.push(dataObj);
    }
    return frameArray;
}

function deserialize(dataId, dataValue) {
    var measurementArray = [];
    switch (dataId) {
        case '01':
            measurementArray = getUpShortInfo(dataValue);
            break;
        case '02':
            measurementArray = getUpShortInfo(dataValue);
            break;
        case '05':
            measurementArray = [{ field: 'BATTERY', value: getBattery(dataValue.substring(0, 2)) }];
            break;
        case '06':
            measurementArray = [{ field: 'DEVICE_LOCATION', value: '(' + getSensorValue(dataValue.substring(24, 32), 1000000) + ',' + getSensorValue(dataValue.substring(16, 24), 1000000) + ')' }, { field: 'AIR_TEMPERATURE', value: getSensorValue(dataValue.substring(32, 36), 10) }, { field: 'LIGHT', value: getSensorValue(dataValue.substring(36, 40)) }, { field: 'Battery', value: getBattery(dataValue.substring(40, 42)) }];
            break;
        case '09':
            measurementArray = [{ field: 'DEVICE_LOCATION', value: '(' + getSensorValue(dataValue.substring(24, 32), 1000000) + ',' + getSensorValue(dataValue.substring(16, 24), 1000000) + ')' }, { field: 'Battery', value: getBattery(dataValue.substring(32, 34)) }];
            break;
    }
    return measurementArray;
}

function getUpShortInfo(messageValue) {
    return [{
        field: 'BATTERY', value: getBattery(messageValue.substring(0, 2))
    }, {
        field: 'HARDWARE_VERSION', value: getSoftVersion(messageValue.substring(2, 6))
    }, {
        field: 'FIRMWARE_VERSION', value: getHardVersion(messageValue.substring(6, 10))
    }, {
        field: 'HEARTBEAT_INTERVAL', value: getOneWeekInterval(messageValue.substring(14, 18))
    }, {
        field: 'UPLINK_INTERVAL', value: getOneWeekInterval(messageValue.substring(18, 22))
    }];
}
function getBattery(batteryStr) {
    return loraWANV2DataFormat(batteryStr);
}
function getSoftVersion(softVersion) {
    return loraWANV2DataFormat(softVersion.substring(0, 2)) + '.' + loraWANV2DataFormat(softVersion.substring(2, 4));
}
function getHardVersion(hardVersion) {
    return loraWANV2DataFormat(hardVersion.substring(0, 2)) + '.' + loraWANV2DataFormat(hardVersion.substring(2, 4));
}

function getOneWeekInterval(str) {
    return loraWANV2DataFormat(str);
}
function getSensorValue(str, dig) {
    if (str === '8000') {
        return null;
    } else {
        return loraWANV2DataFormat(str, dig);
    }
}

function bytes2HexString(arrBytes) {
    var str = '';
    for (var i = 0; i < arrBytes.length; i++) {
        var tmp;
        var num = arrBytes[i];
        if (num < 0) {
            tmp = (255 + num + 1).toString(16);
        } else {
            tmp = num.toString(16);
        }
        if (tmp.length === 1) {
            tmp = '0' + tmp;
        }
        str += tmp;
    }
    return str;
}
function loraWANV2DataFormat(str) {
    var divisor = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 1;

    var strReverse = bigEndianTransform(str);
    var str2 = toBinary(strReverse);
    if (str2.substring(0, 1) === '1') {
        var arr = str2.split('');
        var reverseArr = arr.map(function (item) {
            if (parseInt(item) === 1) {
                return 0;
            } else {
                return 1;
            }
        });
        str2 = parseInt(reverseArr.join(''), 2) + 1;
        return '-' + str2 / divisor;
    }
    return parseInt(str2, 2) / divisor;
}

function bigEndianTransform(data) {
    var dataArray = [];
    for (var i = 0; i < data.length; i += 2) {
        dataArray.push(data.substring(i, i + 2));
    }
    return dataArray;
}

function toBinary(arr) {
    var binaryData = arr.map(function (item) {
        var data = parseInt(item, 16).toString(2);
        var dataLength = data.length;
        if (data.length !== 8) {
            for (var i = 0; i < 8 - dataLength; i++) {
                data = '0' + data;
            }
        }
        return data;
    });
    var ret = binaryData.toString().replace(/,/g, '');
    return ret;
}