packet-decoder/src/devices/PNI/PlacePod.js

SenRa Packet Decoder For IOT devices

class PlacePod {
    constructor(packet) {
        packet = packet.toUpperCase();
        this.packet_type = this.getPacketType(packet.substring(0, 2));
        this.payload = this.getPayload(packet.substring(2, 26));
        this.time_stamp = Buffer.from(packet.substring(26, 34), 'hex').readUInt32LE();
    }

    comparePacket(prev_packet) {
        if (this.payload.car_status !== prev_packet.payload.car_status) return false;
        return true;
    }

    getPacketType(packet_type) {

        switch (packet_type) {
            case '15':
                return 'CAR_DETECTOR_SENSOR';
            case '20':
                return 'CAR_DETECTOR_DATA_SENSOR';
            case '21':
                return 'CAR_DRIVE_THROUGH_SENSOR';
            case '30':
                return 'CONFIGURATION_STATE';
            case '31':
                return 'VERSION_INFO';
            case '32':
                return '16_BIT_CAR_MAG_DATA';
            case '33':
                return 'PONG';
            case '34':
                return 'VERSION';
            case '35':
                return 'CONFIGURATION_PARAMETER';
            case '36':
                return 'RADIO_STATS';
            case '37':
                return 'SELF_REPORT';
            case '38':
                return 'TIME_SYNC';
            case '39':
                return 'ALGORITHM_DEBUG';
            case 'FE':
                return 'META_EVENT';
        }
        return null;
    }

    getPayload(payload) {

        switch (this.packet_type) {
            case 'CAR_DETECTOR_SENSOR':
                return {
                    car_status: this.getResult(payload.substring(0, 2)),
                    // flag: this.getFlag(payload.substring(2, 4)),
                    temperature: Buffer.from(payload.substring(4, 12).padEnd(8, '0'), 'hex').readFloatLE(),
                    battery_status: Buffer.from(payload.substring(12, 20).padEnd(8, '0'), 'hex').readFloatLE(),
                    pkt_counter: Buffer.from(payload.substring(22, 24).padEnd(8, '0'), 'hex').readUInt8()
                };
            case 'SELF_REPORT':
                return {
                    car_status: this.getResult(payload.substring(0, 4)),
                    temperature: Buffer.from(payload.substring(8, 12).padEnd(16, '0'), 'hex').readUInt16LE() / 10,
                    battery_status: Buffer.from(payload.substring(4, 8).padEnd(16, '0'), 'hex').readUInt16LE() / 1000,
                    pkt_counter: Buffer.from(payload.substring(22, 24).padEnd(8, '0'), 'hex').readUInt8(),
                };

        }
    }

    getFlag(flag) {
        const buffer = Buffer.from(flag, 'hex');
        flag = buffer.readUInt8().toString(2).padStart(8, '0');
        return {
            confidence: Buffer.from(parseInt(flag.substring(5, 8), 2).toString(16).padStart(2, '0'), 'hex').readUInt8(),
            calibration_complete: Buffer.from(parseInt(flag.substring(4, 5), 2).toString(16).padStart(2, '0'), 'hex').readUInt8(),
            ls_mode: Buffer.from(parseInt(flag.substring(3, 4), 2).toString(16).padStart(2, '0'), 'hex').readUInt8(),
            mag_signature: Buffer.from(parseInt(flag.substring(1, 3), 2).toString(16).padStart(2, '0'), 'hex').readUInt8(),
            rfu: Buffer.from(parseInt(flag.substring(0, 1), 2).toString(16).padStart(2, '0'), 'hex').readUInt8()
        };
    }

    getResult(result) {
        const buffer = Buffer.from(result, 'hex');
        if (result.length === 2) {
            result = Number(buffer.readUInt8()).toString(16).padStart(2, '0');
        } else if (result.length === 4) {
            result = Number(buffer.readUInt16LE()).toString(16).padStart(2, '0');
        }
        switch (result) {
            case '00':
                return 'UNINITIALIZED';
            case '01':
                return 'NO_CAR';
            case '02':
                return 'CAR_ENTERING';
            case '03':
                return 'CAR_PARKED';
            case '04':
                return 'CAR_LEAVING';
        }
        return null;
    }
}

module.exports = PlacePod;