app/modules/ModbusServer.js

'use strict'
/**
 * Copyright (c) 2017~2022, OBCon Inc.
 * All rights reserved.
 */

/**
 * @file
 * @copyright 2017~2022, OBCon Inc.
 * @author gye hyun james kim [pnuskgh@gmail.com]
 */

//--- Buffer
//---     LE (Little-Endian, 리틀 엔디안) : 인텔에서 동작시 (Default)
//---         LSB (Least Significant Bit) : 낮은 단위를 앞에 저장
//---         0A0B0C0D 데이터 -> 0D, 0C, 0B, 0A 순서로 저장
//---     BE (Big-Endian, 빅 엔디안) : Network에서 처리시, Modbus에서 기본 (Modbus CRC는 LE)
//---         MSP (Most Significant Bit) : 큰 단위를 앞에 저장
//---         0A0B0C0D 데이터 -> 0A, 0B, 0C, 0D 순서로 저장
//---     
//---     생성
//---         let buf = Buffer.alloc(length, char);                             //--- 초기화 (char의 default 값은 0)
//---         let buf = Buffer.allocUnsafe(length);                             //--- 초기화 하지 않음
//---         let buf = Buffer.from([1, 2, 3]);
//---     비교 
//---         let idx = buf.indexOf(char);
//---     결합
//---         let buf = Buffer.concat([buf001, buf002]);
//---     자르기
//---         let buf = buf1.slice(idx, length);
//--- 
//---     읽기
//---         
//---         let str = buf.toString('UTF-8', start, end + 1);
//---         let uint = buf.readUInt8(idx);
//---             readUIntLE(offset, length), readUIntBE(offset, length), readIntLE(offset, length), readIntBE(offset, length)
//---             readUInt8 (0 ~ 255), readUInt16LE, readUInt16BE (0 ~ 65,535), readUInt32LE, readUInt32BE (0 ~ 4,294,967,295), readBigUInt64BE, readBigUInt64LE
//---             readInt8 (-128 ~ 127), readInt16LE, readInt16BE (–32,768 ~ 32,767), readInt32LE, readInt32BE (–2,147,483,648 ~ 2,147,483,647), readBigInt64BE, readBigInt64LE
//---             readFloatLE, readFloatBE (3.4E+/-38(7개의 자릿수), 4 bytes), readDoubleLE, readDoubleBE (1.7E+/-308(15개의 자릿수), 8 bytes)
//---     쓰기
//---         buf.fill(char);
//---         writeUIntLE(value, offset, length), writeUIntBE(value, offset, length), writeIntLE(value, offset, length), writeIntBE(value, offset, length)
//---         writeUInt8(value, offset), writeUInt16LE(value, offset), writeUInt16BE(value, offset), writeUInt32LE(value, offset), writeUInt32BE(value, offset), writeBigUInt64BE(value, offset), writeBigUInt64LE(value, offset)
//---         writeInt8(value, offset), writeInt16LE(value, offset), writeInt16BE(value, offset), writeInt32LE(value, offset), writeInt32BE(value, offset), writeBigInt64BE(value, offset), writeBigInt64LE(value, offset)
//---         writeFloatLE(value, offset), writeFloatBE(value, offset), writeDoubleLE(value, offset), writeDoubleBE(value, offset)
//---     Modbus
//---         readUInt16BE, readInt16BE
//---         writeUInt16BE, writeInt16BE
//---         in CRC
//---             readUInt16LE, readInt16LE
//---             writeUInt16LE, writeInt16LE

let net = require('net');
let jsmodbus = require("jsmodbus");
let { v1: uuidv1 } = require('uuid');
let moment = require('moment');

let ModbusServerClientClass = utils.getClass('modules', 'ModbusServerClient.js');

class ModbusServer {
    constructor() {
        this._host = null;
        this._port = null;

        this._netServer = null;                             //--- net.Server
        this._server = null;                                //--- ModbusTCPServer
        this._clients = [];                                 //--- Client와 연결된 ModbusServerClient

        //--- Modbus Object Type                                                                                         SCADA에서 용도 설정
        //---     Coil              : Read/Write,  1 bit, address - 0x0000 ~ 0xFFFF : 디지털 출력                       : 장비 데이터를 변경 한다.
        //---     Discrete input    : Read,        1 bit, address - 0x0000 ~ 0xFFFF : 디지털 입력                       : 장비 데이터를 가져 온다.              
        //---     Input register    : Read,       16 bit, address - 0x0000 ~ 0xFFFF : 아날로그 입력 또는 내부 메모리용    : 장비 설정을 가져 온다.
        //---     Holding register  : Read/Write, 16 bit, address - 0x0000 ~ 0xFFFF : 래치메모리용                      : 장비 설정을 변경 한다.
        this._coils = {
            device_100 : Buffer.from([
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
            ])
        };
        this._discrete = {
            device_100 : Buffer.from([
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
            ])
        };
        this._input = {
            device_100 : Buffer.from([
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
            ])
        };
        this._holding = {
            device_100 : Buffer.from([
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
                0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xab, 0xcd,
            ])
        };

        this._maxPos = 32;
        // this._devices = {};                                 //--- Device 저장. 'device_{id}
    }

    //--- Server : listen() 함수 호출시
    //---     Server : onNetListening  >  listen
    //--- 
    //--- Client : connect() 함수 호출시
    //---     Server : createServer(socket)  >  onNetConnection(socket)  >  onConnection(client)
    //---         socket                                    : client._socket
    //---         client                                    : ModbusServerClient
    //---             _server                               : ModbusTCPServer
    //---             _socket                               : Socket. 위의 socket 전달값과 동일
    //---             _requestHandler                       : 
    //---             _responseHandler                      : 
    //---     Client : onConnect()  >  connect()  >  onReady()
    //--- 
    //--- Client : connect() 함수 호출시 서버가 없을 경우
    //---     Client : onError(err)  >  onClose(hadError = true)
    //--- 
    //--- Client에서 비정상 접속 종료시
    //---     ServerClient : onError(err)  >  onClose(hadError = true)
    //--- 
    //--- Server에서 비정상 접속 종료시
    //---     Client : onError(err)  >  onClose(hadError = true)
    //--- 
    //--- 
    //--- *** modbus-server-response-handler.js 참조
    //--- Client에서 readDiscreteInputs() 함수 호출시
    //---     Client : readDiscreteInputs(start, count)  >  onData(data)  >  Client(res, err)
    //---     Server : onPreReadDiscreteInputs(request, cb)  >  onPostReadDiscreteInputs(request, cb)  >  ServerClient : onData(data)
    //--- 
    //--- Client에서 readCoils() 함수 호출시 : new jsmodbus.server.TCP(this._netServer, options)에서 지정한 options.coils의 값을 반환
    //---     Client : readCoils(start, count)  >  onData(data)  >  Client(res, err)
    //---     Server : onPreReadCoils(request, cb)  >  onPostReadCoils(request, cb)  >  ServerClient : onData(data)
    //---         request                                   : {"_id":1,"_protocol":0,"_length":6,"_unitId":245,"_body":{"_fc":1,"_start":0,"_count":13}}
    //---         res
    //---             request                               : ModbusTCPRequest - {"_id":1,"_protocol":0,"_length":6,"_unitId":245,"_body":{"_fc":1,"_start":0,"_count":13}}
    //---             response                              : ModbusTCPResponse - {"_id":1,"_protocol":0,"_bodyLength":5,"_unitId":245,"_body":{"_fc":1,"_coils:~,_numberOfBytes:2,_valueAsBuffer:~,_valueAsArray:~"}}
    //---                 _body
    //---                     _coils                        : Buffer
    //---                     _numberOfBytes                : _coils의 bytes 수
    //---                     _valueAsBuffer                : _coils에 해당하는 Buffer
    //---                     _valueAsArray                 : _coils에 해당하는 bit의 배열
    //---         err
    //--- 
    //--- Client에서 writeMultipleCoils() 함수 호출시 : 
    //---     Client : writeMultipleCoils(start, values, quantity)  >  onData(data)  > Client(res, err)
    //---     Server : onPreWriteMultipleCoils(request, cb)  >  onWriteMultipleCoils(request, cb)  >  onPostWriteMultipleCoils(request<Buffer>, cb)  >  onPostWriteMultipleCoils(request<ModbusTCPRequest>, cb)  >  ServerClient : onData(data)
    createServer() {

        this._netServer = new net.Server(function(socket) {
             logger.info(`modules/ModbusServer.js :: createServer(socket)`);
        });
        this._netServer.on('close', this.onNetClose.bind(this));
        this._netServer.on('connection', this.onNetConnection.bind(this));
        this._netServer.on('error', this.onNetError.bind(this));
        this._netServer.on('listening', this.onNetListening.bind(this));

        let options = {
            coils: false,
            discrete: false, 
            input: false, 
            holding: false,
            // coils: Buffer.from([0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef]),
            // discrete: Buffer.from([0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef]),
            // input: Buffer.from([0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef]),
            // holding: Buffer.from([0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef])
        };
        this._server = new jsmodbus.server.TCP(this._netServer, options);
        this._server.on('connection', this.onConnection.bind(this));

        //--- Data Access  >  Bit access  >  Physical Discrete Inputs  >  Read Discrete Inputs
        this._server.on('readDiscreteInputs', this.onReadDiscreteInputs.bind(this));                //--- fc : 2
        this._server.on('preReadDiscreteInputs', this.onPreReadDiscreteInputs.bind(this));
        this._server.on('postReadDiscreteInputs', this.onPostReadDiscreteInputs.bind(this));

        //--- Data Access  >  Bit access  >  Internal Bits or Physical Coils  >  Read Coils
        this._server.on('readCoils', this.onReadCoils.bind(this));                                  //--- fc : 1
        this._server.on('preReadCoils', this.onPreReadCoils.bind(this));
        this._server.on('postReadCoils', this.onPostReadCoils.bind(this));

        //--- Data Access  >  Bit access  >  Internal Bits or Physical Coils  >  Write Single Coil
        this._server.on('writeSingleCoil', this.onWriteSingleCoil.bind(this));                      //--- fc: 5
        this._server.on('preWriteSingleCoil', this.onPreWriteSingleCoil.bind(this));
        this._server.on('postWriteSingleCoil', this.onPostWriteSingleCoil.bind(this));

        //--- Data Access  >  Bit access  >  Internal Bits or Physical Coils  >  Write Multiple Coils
        this._server.on('writeMultipleCoils', this.onWriteMultipleCoils.bind(this));                //--- fc : 15
        this._server.on('preWriteMultipleCoils', this.onPreWriteMultipleCoils.bind(this));
        this._server.on('postWriteMultipleCoils', this.onPostWriteMultipleCoils.bind(this));

        //--- Data Access  >  16-bit access  >  Physical Input Registers  >  Read Input Register
        this._server.on('readInputRegisters', this.onReadInputRegisters.bind(this));                //--- fc : 4
        this._server.on('preReadInputRegisters', this.onPreReadInputRegisters.bind(this));
        this._server.on('postReadInputRegisters', this.onPostReadInputRegisters.bind(this));

        //--- Data Access  >  16-bit access  >  Internal Registers or Physical Output Registers  >  Read Multiple Holding Registers, fc : 3
        this._server.on('readHoldingRegisters', this.onReadHoldingRegisters.bind(this));
        this._server.on('preReadHoldingRegisters', this.onPreReadHoldingRegisters.bind(this));
        this._server.on('postReadHoldingRegisters', this.onPostReadHoldingRegisters.bind(this));

        //--- Data Access  >  16-bit access  >  Internal Registers or Physical Output Registers  >  Write Single Holding Register, fc : 6
        this._server.on('writeSingleRegister', this.onWriteSingleRegister.bind(this));
        this._server.on('preWriteSingleRegister', this.onPreWriteSingleRegister.bind(this));
        this._server.on('postWriteSingleRegister', this.onPostWriteSingleRegister.bind(this));

        //--- Data Access  >  16-bit access  >  Internal Registers or Physical Output Registers  >  Write Multiple Holding Registers, fc : 16
        this._server.on('writeMultipleRegisters', this.onWriteMultipleRegisters.bind(this));
        this._server.on('preWriteMultipleRegisters', this.onPreWriteMultipleRegisters.bind(this));
        this._server.on('postWriteMultipleRegisters', this.onPostWriteMultipleRegisters.bind(this));

        //--- Data Access  >  16-bit access  >  Internal Registers or Physical Output Registers  >  Read/Write Multiple Registers, fc : 23
        //--- Data Access  >  16-bit access  >  Internal Registers or Physical Output Registers  >  Mask Write Register, fc : 22
        //--- Data Access  >  16-bit access  >  Internal Registers or Physical Output Registers  >  Read FIFO Queue, fc : 24

        //--- Data Access  >  File Record Access  > Read File Record , fc : 20
        //--- Data Access  >  File Record Access  > Write File Record , fc : 21

        //--- Diagnostics  >  Read Exception Status, fc : 7, serial only
        //--- Diagnostics  >  Diagnostic, fc : 8, serial only
        //--- Diagnostics  >  Get Com Event Counter, fc : 11, serial only
        //--- Diagnostics  >  Get Com Event Log, fc : 12, serial only
        //--- Diagnostics  >  Report Server ID, fc : 17, serial only
        //--- Diagnostics  >  Read Device Identification, fc : 43, serial only

        //--- Other  >  Encapsulated Interface Transport, fc : 43 
    }

    listen(host, port) {
        this._host = host;
        this._port = port;

        this._netServer.listen(this._port, this._host, function() {
            logger.info(`modules/ModbusServer.js :: listen()`);
            logger.info(' ');
        }.bind(this));
    }

    //----------------------------------------------------------------------------------------------
    //--- Modbus Server 처리 함수
    //----------------------------------------------------------------------------------------------
    //--- on(event: 'connection', listener: (client: ModbusServerClient<any, any, any>) => void): this;
    //--- on(event: 'connection', listener: (socket: Socket) => void): this;
    onConnection(client) {
        client._guid = uuidv1();
        this._clients.push(client);
        logger.info(`modules/ModbusServer.js :: onConnection(client), client count : ${this._clients.length}`);
        this._displayClients();
        logger.info(' ');

        let serverClient = new ModbusServerClientClass(this, client);
    }

    //--- 장비로부터 데이터를 읽어서 값을 반환 한다.
    _getCoils(request) {
        if (typeof(this._coils[`device_${request.unitId}`]) != 'undefined') {
            return this._coils[`device_${request.unitId}`];
        }
        return null;
    }

    //--- Client로부터 받은 값으로 장비를 설정 한다.
    _setCoils(unitId, newValue) {
        this._coils[`device_${unitId}`] = newValue;
    }

    _getDiscrete(request) {
        if (typeof(this._discrete[`device_${request.unitId}`]) != 'undefined') {
            return this._discrete[`device_${request.unitId}`];
        }
        return null;
    }

    _SetDiscrete(unitId, newValue) {
        this._discrete[`device_${unitId}`] = newValue;
    }

    _getInput(request) {
        if (typeof(this._input[`device_${request.unitId}`]) != 'undefined') {
            return this._input[`device_${request.unitId}`];
        }
        return null;
    }

    _SetInput(unitId, newValue) {
        this._input[`device_${unitId}`] = newValue;
    }

    _getHolding(request) {
        if (typeof(this._holding[`device_${request.unitId}`]) != 'undefined') {
            return this._holding[`device_${request.unitId}`];
        }
        return null;
    }

    _setHolding(unitId, newValue) {
        this._holding[`device_${unitId}`] = newValue;
    }

    //--- readDiscreteInputs(start, count) : Client에서 bit 단위의 discrete(디지털 입력)을 가져 온다.
    //---     start : 시작 주소 (0, 1, 2, ...)
    //---     count : bits 수
    //--- onReadDiscreteInputs(request, cb)
    //---     request   : ModbusTCPRequest
    //---     cb        : 인수로 받은 Buffer를 Client로 전송 한다.
    //--- this._server.discrete가 false인 경우, onReadDiscreteInputs()가 호출된다.
    //--- this._server.discrete가 Buffer인 경우, modbus-server-response-handler.js에 정의된대로 실행 된다.
    //---
    //--- Data Access  >  Bit access  >  Physical Discrete Inputs  >  Read Discrete Inputs
    //--- on(event: 'readDiscreteInputs', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onReadDiscreteInputs(request, cb) {
        logger.info(`modules/ModbusServer.js :: onReadDiscreteInputs, ${JSON.stringify(request)}`);
        this._errorResponse(request, cb, 0x01);

        // let discrete = this._getDiscrete(request);
        // if (discrete != null) {
        //     const responseBody = jsmodbus.responses.ReadDiscreteInputsResponseBody.fromRequest(request.body, discrete);
        //     const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
        //     const payload = response.createPayload();
        //     cb(payload);
        // }
    }

    //--- on(event: 'preReadDiscreteInputs', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPreReadDiscreteInputs(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPreReadDiscreteInputs, ${JSON.stringify(request)}`);
    }

    //--- on(event: 'postReadDiscreteInputs', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPostReadDiscreteInputs(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPostReadDiscreteInputs, ${JSON.stringify(request)}`);
    }

    //--- readCoils(start, count) : Client에서 bit 단위의 coils(디지털 출력)을 가져 온다.
    //---     start : 시작 주소 (0, 1, 2, ...)
    //---     count : bits 수
    //--- Data Access  >  Bit access  >  Internal Bits or Physical Coils  >  Read Coils
    //--- on(event: 'readCoils', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onReadCoils(request, cb) {
        logger.info(`modules/ModbusServer.js :: onReadCoils, ${JSON.stringify(request)}`);
        this._errorResponse(request, cb, 0x01);

        // let coils = this._getCoils(request);
        // if (coils != null) {
        //     const responseBody = jsmodbus.responses.ReadCoilsResponseBody.fromRequest(request.body, coils);
        //     const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
        //     const payload = response.createPayload();
        //     cb(payload);
        // }
    }

    //--- on(event: 'preReadCoils', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPreReadCoils(request, cb) {
        logger.info('');
        logger.info(`modules/ModbusServer.js :: onPreReadCoils(request, cb), ${JSON.stringify(request)}`);
        //--- request : {"_id":1,"_protocol":0,"_length":6,"_unitId":245,"_body":{"_fc":1,"_start":0,"_count":13}}
    }

    //--- on(event: 'postReadCoils', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPostReadCoils(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPostReadCoils(request, cb), ${JSON.stringify(request)}`);
        //--- request : {"_id":1,"_protocol":0,"_length":6,"_unitId":245,"_body":{"_fc":1,"_start":0,"_count":13}}
    }

    //--- writeSingleCoil(address, value) : Client에서 하나의 bit를 coils(디지털 출력)에 기록 한다.
    //---     address : 주소
    //---     value : 값 (true, false) 또는 new Buffer(0x01)
    //--- Data Access  >  Bit access  >  Internal Bits or Physical Coils  >  Write Single Coil
    // on(event: 'writeSingleCoil', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onWriteSingleCoil(request, cb) {
        logger.info(`modules/ModbusServer.js :: onWriteSingleCoil, ${JSON.stringify(request)}`);
        this._errorResponse(request, cb, 0x01);

        // let coils = this._getCoils(request);
        // if (coils != null) {
        //     const responseBody = jsmodbus.responses.WriteSingleCoilResponseBody.fromRequest(request.body);
        //     const address = request.body.address;
        //     const oldValue = coils.readUInt8(Math.floor(address / 8));
        //     let newValue;
        //     if ((request.body.value !== 0xFF00) && (request.body.value !== 0x0000)) {
        //         const exceptionBody = new jsmodbus.responses.ExceptionResponseBody(request.body.fc, 0x03);
        //         const exceptionResponse = jsmodbus.ModbusTCPResponse.fromRequest(request, exceptionBody);
        //         cb(exceptionResponse.createPayload());
        //         return;
        //     }
        //     if (request.body.value === 0xFF00) {
        //         newValue = oldValue | Math.pow(2, address % 8);
        //     }
        //     else {
        //         newValue = oldValue & ~Math.pow(2, address % 8);
        //     }
        //     // logger.info(`    ${address}, ${request.body.value} -> ${oldValue}, ${newValue}`);
        //     if (responseBody.address / 8 > coils.length) {
        //         const exceptionBody = new jsmodbus.responses.ExceptionResponseBody(request.body.fc, 0x02);
        //         const exceptionResponse = jsmodbus.ModbusTCPResponse.fromRequest(request, exceptionBody);
        //         cb(exceptionResponse.createPayload());
        //         return;
        //     }
        //     else {
        //         coils.writeUInt8(newValue, Math.floor(address / 8));
        //         this._setCoils(request.unitId, coils);
        //     }
        //     const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
        //     const payload = response.createPayload();
        //     cb(payload);
        // }
    }

    // on(event: 'preWriteSingleCoil', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPreWriteSingleCoil(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPreWriteSingleCoil, ${JSON.stringify(request)}`);
    }

    // on(event: 'postWriteSingleCoil', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPostWriteSingleCoil(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPostWriteSingleCoil, ${JSON.stringify(request)}`);
    }

    //--- Data Access  >  Bit access  >  Internal Bits or Physical Coils  >  Write Multiple Coils
    //--- on(event: 'writeMultipleCoils', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    //--- on(event: 'writeMultipleCoils', listener: (coils: Buffer, oldStatus: BooleanArray) => void): this;
    //--- xx request : this._server의 coils의 Buffer
    //--- xx cb : this._server의 coils의 bits 배열
    async onWriteMultipleCoils(request, cb) {
        logger.info(`modules/ModbusServer.js :: onWriteMultipleCoils(request<Buffer>, cb)`);
        this._errorResponse(request, cb, 0x01);

        // let coils = this._getCoils(request);
        // if (coils != null) {
        //     const responseBody = jsmodbus.responses.WriteMultipleCoilsResponseBody.fromRequest(request.body);
        //     const oldStatus = this.bufferToArrayStatus(coils);
        //     const requestCoilValues = this.bufferToArrayStatus(request.body.valuesAsBuffer);
        //     const start = request.body.address;
        //     const end = start + request.body.quantity;
        //     const newStatus = oldStatus.map((byte, i) => {
        //         let value = byte;
        //         const inRange = (i >= start && i < end);
        //         if (inRange) {
        //             const newValue = requestCoilValues.shift();
        //             value = (newValue !== undefined) ? newValue : byte;
        //         }
        //         return value;
        //     });
        //     // this._server.emit('writeMultipleCoils', coils, oldStatus);
        //     coils.fill(this.arrayStatusToBuffer(newStatus));
        //     this._setCoils(request.unitId, coils);
        //     // this._server.emit('postWriteMultipleCoils', coils, newStatus);
        //     const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
        //     const payload = response.createPayload();
        //     cb(payload);
        // }
    }

    //--- on(event: 'preWriteMultipleCoils', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    //--- request : ModbusTCPRequest
    async onPreWriteMultipleCoils(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPreWriteMultipleCoils(request<ModbusTCPRequest>, cb)`);
        // logger.info(`    request<ModbusTCPRequest> : ${JSON.stringify(request)}`);
        // logger.info(`    cb : ${JSON.stringify(cb)}`);
        // logger.info(request);
    }

    //--- on(event: 'postWriteMultipleCoils', listener: (coils: Buffer, newStatus: BooleanArray) => void): this;
    //--- on(event: 'postWriteMultipleCoils', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPostWriteMultipleCoils(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPostWriteMultipleCoils(request<ModbusTCPRequest>, cb)`);
        // if (request instanceof Buffer) {
        //     logger.info(`modules/ModbusServer.js :: onPostWriteMultipleCoils(request<Buffer>, cb)`);
        //     logger.info(`    request<Buffer> : ${this._bufferToHex(request)}`);         //--- request : Buffer
        //     logger.info(`    cb : ${JSON.stringify(cb)}`);
        // } else {
        //     logger.info(`modules/ModbusServer.js :: onPostWriteMultipleCoils(request<ModbusTCPRequest>, cb)`);
        //     logger.info(`    request<ModbusTCPRequest> : ${JSON.stringify(request)}`);            //--- request : ModbusTCPRequest
        //     logger.info(`    cb : ${JSON.stringify(cb)}`);
        // }
    }

    //--- Data Access  >  16-bit access  >  Physical Input Registers  >  Read Input Register
    // on(event: 'readInputRegisters', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onReadInputRegisters(request, cb) {
        logger.info(`modules/ModbusServer.js :: onReadInputRegisters, ${JSON.stringify(request)}`);
        logger.info(`modules/ModbusServer.js :: onReadInputRegisters, unitId : ${request.unitId}, start : ${request.body.start}, count : ${request.body.count}`);

        let modbusId = Math.floor(request.body.start / request.unitId);
        let buf = await this._getDeviceData(modbusId, request.unitId);
        if (buf == null) {
            this._errorResponse(request, cb, 0x03);
        } else {
            const responseBody = jsmodbus.responses.ReadInputRegistersResponseBody.fromRequest(request.body, buf);
            const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
            const payload = response.createPayload();
            cb(payload);
        }

        // let input = this._getInput(request);
        // if (input != null) {
        //     const responseBody = jsmodbus.responses.ReadHoldingRegistersResponseBody.fromRequest(request.body, input);
        //     const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
        //     const payload = response.createPayload();
        //     cb(payload);
        // }
    }

    async _getDeviceData(modbusId, unitId) {
        try {
            logger.info(`modules/ModbusServer.js :: _getDeviceData, modbusId : ${modbusId}`);
            let query = { where: { modbusId: modbusId, site: config.modbus.kwater.site, deleted: false } };
            let device = await modules.devices.model.table.findOne(query);
            if (device == null) {
                logger.error(`modules/ModbusServer.js :: _getDeviceData, modbusId : ${modbusId}, device not found.`);
                return null;
            }

            query = { 
                where: { deviceKey: device.deviceKey },
                order: [ ['id', 'DESC'] ],
                limit: 1
            };
            let devicedata2s = await modules.devicedata2s.model.table.findAll(query);
            if (devicedata2s.length != 1) {
                logger.error(`modules/ModbusServer.js :: _getDeviceData, modbusId : ${modbusId}, devicedata2s not found.`);
                return null;
            }
            let devicedata2 = devicedata2s[0];

            let address = modbusId * unitId;
            let buf = Buffer.alloc((modbusId + 1) * (2 * unitId), 0x00);
            buf.write(devicedata2.siteKey, 2 * address, 'UTF-8');                                   address = address + 1;
            buf.write(' ' + devicedata2.type, 2 * address, 'UTF-8');                                address = address + 1;
            buf.write(devicedata2.deviceKey, 2 * address, 'UTF-8');                                 address = address + 2;

            buf.write(devicedata2.statusDatetime.substring(2), 2 * address, 'UTF-8');               address = address + 6;
            buf.writeFloatBE(devicedata2.ac, 2 * address);                                          address = address + 2;
            buf.writeFloatBE(devicedata2.preventPotential, 2 * address);                            address = address + 2;
            buf.writeFloatBE(devicedata2.batteryVoltage, 2 * address);                              address = address + 2;
            buf.writeFloatBE(devicedata2.sensitivity, 2 * address);                                 address = address + 2;

            buf.write(' ' + devicedata2.dataMode, 2 * address, 'UTF-8');                            address = address + 1;
            buf.writeInt16BE(devicedata2.dataCycle, 2 * address);                                   address = address + 1;
            buf.writeInt16BE(devicedata2.networkCycle, 2 * address);                                address = address + 1;

            switch (device.interfaceVersion) {
            case '1.00':
                buf.write(0x0000, 2 * address, 'UTF-8');                                            address = address + 1;
                buf.write(0x0000, 2 * address, 'UTF-8');                                            address = address + 1;
                buf.write(0x0000, 2 * address, 'UTF-8');                                            address = address + 1;
                break;
            default:
                buf.writeFloatBE(devicedata2.temperature, 2 * address);                             address = address + 2;
                buf.writeInt16BE(devicedata2.humidity, 2 * address);                                address = address + 1;
                break;
            }

            address = address + (17 - 1);
            buf.write('' + devicedata2.dataMode, 2 * address, 'UTF-8');                             address = address + 1;
            buf.writeInt16BE(devicedata2.dataCycle, 2 * address);                                   address = address + 1;
            buf.writeInt16BE(devicedata2.networkCycle, 2 * address);                                address = address + 1;
            return buf;
        } catch (err) {
            return null;
        }
    }

    // on(event: 'preReadInputRegisters', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPreReadInputRegisters(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPreReadInputRegisters, ${JSON.stringify(request)}`);
    }

    // on(event: 'postReadInputRegisters', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPostReadInputRegisters(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPostReadInputRegisters, ${JSON.stringify(request)}`);
    }

    //--- Data Access  >  16-bit access  >  Internal Registers or Physical Output Registers  >  Read Multiple Holding Registers, fc : 3
    // on(event: 'readHoldingRegisters', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onReadHoldingRegisters(request, cb) {
        logger.info(`modules/ModbusServer.js :: onReadHoldingRegisters, ${JSON.stringify(request)}`);

        let modbusId = Math.floor(request.body.start / request.unitId);
        let buf = await this._getDeviceData(modbusId, request.unitId);
        if (buf == null) {
            this._errorResponse(request, cb, 0x03);
        } else {
            const responseBody = jsmodbus.responses.ReadHoldingRegistersResponseBody.fromRequest(request.body, buf);
            const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
            const payload = response.createPayload();
            cb(payload);
        }

        // let holding = this._getHolding(request);
        // if (holding != null) {
        //     const responseBody = jsmodbus.responses.ReadHoldingRegistersResponseBody.fromRequest(request.body, holding);
        //     const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
        //     const payload = response.createPayload();
        //     cb(payload);
        // }
    }

    // on(event: 'preReadHoldingRegisters', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPreReadHoldingRegisters(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPreReadHoldingRegisters, ${JSON.stringify(request)}`);
    }

    // on(event: 'postReadHoldingRegisters', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPostReadHoldingRegisters(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPostReadHoldingRegisters, ${JSON.stringify(request)}`);
    }

    //--- Data Access  >  16-bit access  >  Internal Registers or Physical Output Registers  >  Write Single Holding Register, fc : 6
    // on(event: 'writeSingleRegister', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onWriteSingleRegister(request, cb) {
        logger.info(`modules/ModbusServer.js :: onWriteSingleRegister, ${JSON.stringify(request)}`);
        this._errorResponse(request, cb, 0x01);

        // let holding = this._getHolding(request);
        // if (holding != null) {
        //     const responseBody = jsmodbus.responses.WriteSingleRegisterResponseBody.fromRequest(request.body);
        //     if (responseBody.address * 2 > holding.length) {
        //         const exceptionBody = new jsmodbus.responses.ExceptionResponseBody(request.body.fc, 0x02);
        //         const exceptionResponse = jsmodbus.ModbusTCPResponse.fromRequest(request, exceptionBody);
        //         cb(exceptionResponse.createPayload());
        //         return;
        //     }
        //     else {
        //         holding.writeUInt16BE(responseBody.value, responseBody.address * 2);
        //         this._setHolding(request.unitId, holding);
        //     }
        //     const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
        //     const payload = response.createPayload();
        //     cb(payload);
        // }
    }

    // on(event: 'preWriteSingleRegister', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPreWriteSingleRegister(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPreWriteSingleRegister, ${JSON.stringify(request)}`);
    }

    // on(event: 'postWriteSingleRegister', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPostWriteSingleRegister(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPostWriteSingleRegister, ${JSON.stringify(request)}`);
    }

    //--- Data Access  >  16-bit access  >  Internal Registers or Physical Output Registers  >  Write Multiple Holding Registers, fc : 16
    // on(event: 'writeMultipleRegisters', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    // on(event: 'writeMultipleRegisters', listener: (holdingRegisters: Buffer) => void): this;
    async onWriteMultipleRegisters(request, cb) {
        logger.info(`modules/ModbusServer.js :: onWriteMultipleRegisters, ${JSON.stringify(request)}`);

        try {
            let modbusId = Math.floor(request.body.address / request.unitId);
            let address = request.body.address - modbusId * request.unitId;
            logger.info(`modules/ModbusServer.js :: onWriteMultipleRegisters, modbusId : ${modbusId}, ${address}`);

            //--- To-Do : 시작 주소가 18이 아니라도 18 ~ 20 address가 포함된 경우 write 처리할 것
            if (address != 18) {
                this._errorResponse(request, cb, 0x02);
                return;
            }
            if (request.body.quantity != 3) {
                this._errorResponse(request, cb, 0x03);
                return;
            }

            let buf = request.body.valuesAsBuffer;
            let dataMode = buf.toString('UTF-8', 0, 2).trim();
            let dataCycle = buf.readUInt16BE(2);
            let networkCycle = buf.readUInt16BE(4);
            logger.info(`Data Mode       : [${dataMode}]`);
            logger.info(`수집주기         : [${dataCycle}]`);
            logger.info(`통신주기         : [${networkCycle}]`);

            let query = { where: { modbusId: modbusId, site: config.modbus.kwater.site, deleted: false } };
            let device = await modules.devices.model.table.findOne(query);
            if (device == null) {
                logger.error(`modules/ModbusServer.js :: onWriteMultipleRegisters, modbusId : ${modbusId}, device not found.`);
                this._errorResponse(request, cb, 0x02);
                return;
            }

            // let isApply = this._getFlagString(device.apply, 2);
            // if (isApply == '0') {
            //     //--- 수정 사항을 장비에 적용하기 전에 원본 데이터 백업
            //     this._devices[`device_${device.id}`] = device;
            // }

            let networkCycleUnit = '분';
            let dataCycleUnit = '분';
            switch (dataMode) {
            case '0':
            case '4':
                networkCycleUnit = '분';
                dataCycleUnit = '분';
                break;
            case '1':
                networkCycleUnit = '시';
                dataCycleUnit = '분';
                break;
            case '2':
                networkCycleUnit = '시';
                dataCycleUnit = '시';
                break;
            case '9':
                break;
            default:
                this._errorResponse(request, cb, 0x03);
                return;
            }

            let item = {
                dataMode: dataMode,
                networkCycle: networkCycle,
                networkCycleUnit: networkCycleUnit,
                dataCycle: dataCycle,
                dataCycleUnit: dataCycleUnit,
                setDatetimeReq: moment().format('YYYY-MM-DDTHH:mm:ss'),
                apply: this._setFlagString(device.apply, 2, '1')
            };

            let results = await modules.devices.model.table.update(item, { where: { id: device.id, deleted: false } });
            if (results[0] != 1) {
                this._errorResponse(request, cb, 0x03);
                return;
            }

            const responseBody = jsmodbus.responses.WriteMultipleRegistersResponseBody.fromRequest(request.body);
            const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
            const payload = response.createPayload();
            cb(payload);
        } catch (err) {
            this._errorResponse(request, cb, 0x02);
        }

        // let holding = this._getHolding(request);
        // if (holding != null) {
        //     const responseBody = jsmodbus.responses.WriteMultipleRegistersResponseBody.fromRequest(request.body);
        //     if (((request.body.address * 2) + request.body.values.length) > holding.length) {
        //         this._errorResponse(request, cb, 0x02);
        //         return;
        //     }
        //     else {
        //         // this._server.emit('writeMultipleRegisters', holding);
        //         holding.fill(new Uint8Array(request.body.values), request.body.address * 2, request.body.address * 2 + request.body.values.length);
        //         this._setHolding(request.unitId, holding);
        //         // this._server.emit('postWriteMultipleRegisters', holding);
        //     }
        //     const response = jsmodbus.ModbusTCPResponse.fromRequest(request, responseBody);
        //     const payload = response.createPayload();
        //     cb(payload);
        // }
    }

    _initFlagString(source) {
        let tmpStr = source + '0000000000000000000000000000000000000000';
        return tmpStr.substring(0, this._maxPos);
    }

    _getFlagString(source, pos) {
        let tmpStr = this._initFlagString(source);
        tmpStr = tmpStr.substring(pos - 1, pos);
        return tmpStr;
    }

    _setFlagString(source, pos, set) {
        let tmpStr = this._initFlagString(source);
        tmpStr = tmpStr.substring(0, pos - 1) + set + tmpStr.substring(pos, this._maxPos);
        return tmpStr;
    }

    // export declare const ErrorMessages: {
    //     readonly 0x01: "ILLEGAL FUNCTION";
    //     readonly 0x02: "ILLEGAL DATA ADDRESS";
    //     readonly 0x03: "ILLEGAL DATA VALUE";
    //     readonly 0x04: "SLAVE DEVICE FAILURE";
    //     readonly 0x05: "ACKNOWLEDGE";
    //     readonly 0x06: "SLAVE DEVICE BUSY";
    //     readonly 0x08: "MEMORY PARITY ERROR";
    //     readonly 0x0A: "GATEWAY PATH UNAVAILABLE";
    //     readonly 0x0B: "GATEWAY TARGET DEVICE FAILED TO RESPOND";
    // };
    _errorResponse(request, cb, errorCode) {
        const exceptionBody = new jsmodbus.responses.ExceptionResponseBody(request.body.fc, errorCode);
        const exceptionResponse = jsmodbus.ModbusTCPResponse.fromRequest(request, exceptionBody);
        cb(exceptionResponse.createPayload());
    }

    // on(event: 'preWriteMultipleRegisters', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPreWriteMultipleRegisters(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPreWriteMultipleRegisters, ${JSON.stringify(request)}`);
    }

    // on(event: 'postWriteMultipleRegisters', listener: (holdingRegisters: Buffer) => void): this;
    // on(event: 'postWriteMultipleRegisters', listener: (request: AbstractRequest, cb: BufferCB) => void): this;
    async onPostWriteMultipleRegisters(request, cb) {
        logger.info(`modules/ModbusServer.js :: onPostWriteMultipleRegisters, ${JSON.stringify(request)}`);
    }

    //----------------------------------------------------------------------------------------------
    //--- Server Socket 처리 함수
    //----------------------------------------------------------------------------------------------
    // this._netServer.on(event: 'close', listener: () => void): this;
    onNetClose() {
        logger.info(`modules/ModbusServer.js :: onNetClose`);
    }

    //--- this._netServer.on(event: 'connection', listener: (socket: Socket) => void): this;
    onNetConnection(socket) {
        logger.info(`modules/ModbusServer.js :: onNetConnection(socket)`);
    }

    // this._netServer.on(event: 'error', listener: (err: Error) => void): this;
    onNetError(err) {
        logger.info(`modules/ModbusServer.js :: onNetError, ${JSON.stringify(err)}`);
    }

    // this._netServer.on(event: 'listening', listener: () => void): this;
    onNetListening() {
        logger.info(`modules/ModbusServer.js :: onNetListening`);
    }

    //----------------------------------------------------------------------------------------------
    //--- 일반 함수
    //----------------------------------------------------------------------------------------------
    _displayClients() {
        for (let idx = 0; idx < this._clients.length; idx++) {
            logger.info(`    client ${idx + 1} : guid - ${this._clients[idx]._guid}`);
        }
    }

    _deleteClient(guid) {
        logger.info(`modules/ModbusServer.js :: _deleteClient, guid : ${guid}`);
        this._clients = this._clients.filter((client) => client._guid != guid);
        this._displayClients();
        logger.info(' ');
    }

    _bufferToHex(buf) {
        let hex = buf.toString('hex');
        let data = [];
        for (let idx = 0; idx < hex.length; idx = idx + 2) {
            data.push(hex.substring(idx, idx + 2));
        }
        return data.join(' ');
    }

    bufferToArrayStatus(buffer) {
        const statusArray = [];
        let pos;
        let curByteIdx;
        let curByte;
        if (!(buffer instanceof Buffer)) {
            return statusArray;
        }
        for (let i = 0; i < buffer.length * 8; i += 1) {
            pos = i % 8;
            curByteIdx = Math.floor(i / 8);
            curByte = buffer.readUInt8(curByteIdx);
            const value = ((curByte & Math.pow(2, pos)) > 0);
            statusArray.push(value ? 1 : 0);
        }
        return statusArray;
    }

    arrayStatusToBuffer(array) {
        const byteCount = array instanceof Array ? Math.ceil(array.length / 8) : 0;
        const buffer = Buffer.alloc(byteCount);
        if (!(array instanceof Array)) {
            return buffer;
        }
        let byteOffset;
        let bitOffset;
        let byte;
        for (let i = 0; i < array.length; i += 1) {
            byteOffset = Math.floor(i / 8);
            bitOffset = i % 8;
            byte = buffer.readUInt8(byteOffset);
            byte += array[i] ? Math.pow(2, bitOffset) : 0;
            buffer.writeUInt8(byte, byteOffset);
        }
        return buffer;
    }
}

module.exports = ModbusServer;