package com.mes.device;

import com.fazecast.jSerialComm.SerialPort;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.math.BigInteger;
import java.util.HashMap;
import java.util.Map;

/**
 * 继电器驱动（Modbus RTU串口通信）
 * 用于控制继电器开关
 */
public class RelayDriver implements IDeviceDriver {
    private static final Logger log = LoggerFactory.getLogger(RelayDriver.class);

    private SerialPort serialPort;
    private String portName = "COM2";
    private int baudrate = 38400;
    private String openCommand = "010600000000";   // 开继电器命令
    private String closeCommand = "010600000001";  // 关继电器命令

    private volatile boolean connected = false;

    public RelayDriver() {
    }

    public RelayDriver(String portName, int baudrate) {
        this.portName = portName;
        this.baudrate = baudrate;
    }

    @Override
    public void connect(Map<String, Object> config) {
        if (config != null) {
            if (config.containsKey("port")) {
                this.portName = config.get("port").toString();
            }
            if (config.containsKey("baudrate")) {
                this.baudrate = ((Number) config.get("baudrate")).intValue();
            }
            if (config.containsKey("open_command")) {
                this.openCommand = config.get("open_command").toString();
            }
            if (config.containsKey("close_command")) {
                this.closeCommand = config.get("close_command").toString();
            }
        }

        try {
            serialPort = SerialPort.getCommPort(portName);
            serialPort.setComPortParameters(baudrate, 8, SerialPort.ONE_STOP_BIT, SerialPort.NO_PARITY);
            serialPort.setComPortTimeouts(SerialPort.TIMEOUT_READ_BLOCKING, 1000, 0);

            if (serialPort.openPort()) {
                connected = true;
                log.info("继电器串口{}打开成功", portName);
            } else {
                connected = false;
                log.error("继电器串口{}打开失败", portName);
            }
        } catch (Exception e) {
            log.error("继电器连接失败: {}", e.getMessage());
            connected = false;
        }
    }

    @Override
    public void disconnect() {
        if (serialPort != null && serialPort.isOpen()) {
            serialPort.closePort();
            log.info("继电器串口已关闭");
        }
        connected = false;
    }

    @Override
    public boolean isConnected() {
        return connected && serialPort != null && serialPort.isOpen();
    }

    /**
     * 开继电器
     */
    public void open() {
        sendCommand(openCommand);
        log.info("继电器已开启");
    }

    /**
     * 关继电器
     */
    public void close() {
        sendCommand(closeCommand);
        log.info("继电器已关闭");
    }

    /**
     * 发送命令
     */
    private void sendCommand(String command) {
        if (!isConnected()) {
            reconnect();
        }
        if (!isConnected()) {
            log.error("继电器未连接，无法发送命令");
            return;
        }

        try {
            String crc = getCRC16ModbusStr(command);
            byte[] writeBuffer = hexStringToByteArray(command + crc);
            serialPort.writeBytes(writeBuffer, writeBuffer.length);

            // 读取响应
            byte[] readBuffer = new byte[512];
            int numRead = serialPort.readBytes(readBuffer, readBuffer.length);
            log.debug("继电器响应: {} bytes", numRead);
        } catch (Exception e) {
            log.error("发送继电器命令失败: {}", e.getMessage());
        }
    }

    /**
     * 重新连接
     */
    private void reconnect() {
        disconnect();
        Map<String, Object> config = new HashMap<>();
        config.put("port", portName);
        config.put("baudrate", baudrate);
        connect(config);
    }

    /**
     * CRC16 Modbus校验
     */
    private String getCRC16ModbusStr(String data) {
        data = data.replace(" ", "");
        int len = data.length();
        if (len % 2 != 0) {
            return "0000";
        }
        int num = len / 2;
        byte[] para = new byte[num];
        for (int i = 0; i < num; i++) {
            int value = Integer.valueOf(data.substring(i * 2, 2 * (i + 1)), 16);
            para[i] = (byte) value;
        }
        return getCRC(para);
    }

    private String getCRC(byte[] bytes) {
        int CRC = 0x0000ffff;
        int POLYNOMIAL = 0x0000a001;
        for (byte b : bytes) {
            CRC ^= ((int) b & 0x000000ff);
            for (int j = 0; j < 8; j++) {
                if ((CRC & 0x00000001) != 0) {
                    CRC >>= 1;
                    CRC ^= POLYNOMIAL;
                } else {
                    CRC >>= 1;
                }
            }
        }
        String result = Integer.toHexString(CRC).toUpperCase();
        if (result.length() != 4) {
            StringBuilder sb = new StringBuilder("0000");
            result = sb.replace(4 - result.length(), 4, result).toString();
        }
        return result.substring(2, 4) + result.substring(0, 2);
    }

    private byte[] hexStringToByteArray(String hexString) {
        hexString = hexString.trim();
        if (hexString.length() % 2 != 0) {
            throw new IllegalArgumentException("Invalid hex string");
        }
        BigInteger bigInt = new BigInteger(hexString, 16);
        byte[] byteArray = bigInt.toByteArray();
        if (byteArray.length > hexString.length() / 2) {
            byte[] trimmedArray = new byte[hexString.length() / 2];
            System.arraycopy(byteArray, 1, trimmedArray, 0, trimmedArray.length);
            return trimmedArray;
        }
        return byteArray;
    }

    // 以下方法继电器驱动不支持
    @Override public void signalReady() { }
    @Override public void startHeartbeat() { }
    @Override public void stopHeartbeat() { }
    @Override public Map<String, Object> readStatus() { return new HashMap<>(); }
    @Override public boolean isWorkComplete() { return false; }
    @Override public int getPresetCount() { return 0; }
    @Override public int getFinishedCount() { return 0; }
    @Override public int getQualifiedCount() { return 0; }
    @Override public void setPresetCount(int count) { }
    @Override public void writeRegister(int address, int value) { }
    @Override public int readRegister(int address) { return 0; }

    @Override
    public String getDriverType() {
        return "relay";
    }

    // Getters & Setters
    public String getPortName() { return portName; }
    public void setPortName(String portName) { this.portName = portName; }
    public int getBaudrate() { return baudrate; }
    public void setBaudrate(int baudrate) { this.baudrate = baudrate; }
    public String getOpenCommand() { return openCommand; }
    public void setOpenCommand(String openCommand) { this.openCommand = openCommand; }
    public String getCloseCommand() { return closeCommand; }
    public void setCloseCommand(String closeCommand) { this.closeCommand = closeCommand; }
}