// ÉùÃ÷°üÃû dell_system
package dell_system;

// µ¼Èë´®¿ÚͨÐÅ¿â
import com.fazecast.jSerialComm.SerialPort;
// µ¼Èë Java º¯Êýʽ½Ó¿Ú Consumer£¬ÓÃÓÚÊý¾Ý½ÓÊջص÷
import java.util.function.Consumer;
// µ¼Èë×Ö½ÚÊý×éÊä³öÁ÷
import java.io.ByteArrayOutputStream;

/**
 * ´®¿Ú·þÎñÀà
 * ¸ºÔ𴮿ڵĴò¿ª¡¢¹Ø±Õ¡¢Êý¾ÝÊÕ·¢
 */
public class SerialPortService {

    // ´®¿Ú¶ÔÏó£¬ÓÃÓÚÓëÓ²¼þͨÐÅ
    private SerialPort port;
    // ±ê¼ÇÊÇ·ñÕýÔÚ²¶»ñÊý¾Ý£¨Ïß³ÌÔËÐÐÖУ©
    private volatile boolean capturing = false;
    // ±ê¼ÇÊÇ·ñÔÝÍ£½ÓÊÕÊý¾Ý
    private volatile boolean paused    = false;

    // Êý¾Ý¶ÁÈ¡Ïß³Ì
    private Thread readerThread;

    /**
     * ´ò¿ª´®¿Ú
     * @param portName ´®¿ÚÃû³Æ£¨Èç COM3£©
     * @param baud ²¨ÌØÂÊ£¨Èç 9600£©
     * @return ÊÇ·ñ³É¹¦´ò¿ª
     */
    public boolean open(String portName, int baud) {
        // Èç¹û´®¿ÚÒÑ´ò¿ª£¬Ö±½Ó·µ»Ø³É¹¦
        if (port != null && port.isOpen()) {
            return true;
        }

        // ¸ù¾ÝÃû³Æ»ñÈ¡´®¿ÚʵÀý
        port = SerialPort.getCommPort(portName);
        // ÉèÖô®¿Ú²ÎÊý£º²¨ÌØÂÊ¡¢Êý¾Ýλ8¡¢Í£Ö¹Î»1¡¢ÎÞУÑéλ
        port.setComPortParameters(baud, 8, 1, SerialPort.NO_PARITY);
        // ÐÞ¸ÄΪ°ë×èÈûģʽ£¬¶Á³¬Ê±1ms
        port.setComPortTimeouts(SerialPort.TIMEOUT_READ_SEMI_BLOCKING, 1, 0);

        // ´ò¿ª´®¿Ú²¢·µ»Ø½á¹û
        return port.openPort();
    }

    /**
     * ¹Ø±Õ´®¿Ú
     */
    public void close() {
        // ÏÈÍ£Ö¹Êý¾Ý½ÓÊÕÏß³Ì
        stopCapture();
        // Èç¹û´®¿ÚÒÑ´ò¿ª£¬¹Ø±ÕËü
        if (port != null && port.isOpen()) {
            port.closePort();
        }
        // ÊÍ·Å´®¿ÚÒýÓÃ
        port = null;
    }

    /**
     * Æô¶¯Êý¾Ý½ÓÊÕÏß³Ì
     * @param onReceived Êý¾Ý½ÓÊջص÷º¯Êý£¬ÊÕµ½Êý¾Ýʱµ÷ÓÃ
     */
    public void startCapture(Consumer<byte[]> onReceived) {
        if (capturing || port == null || !port.isOpen()) return;
        capturing = true;
        paused = false;

        readerThread = new Thread(() -> {
            // ´´½¨Êý¾Ý»º³åÇø
            ByteArrayOutputStream buffer = new ByteArrayOutputStream();
            // ×îºóÊÕµ½Êý¾ÝµÄʱ¼ä´Á
            long lastReceivedTime = 0;
            // ¶ÁÈ¡»º³åÇø
            byte[] readBuffer = new byte[200];
            
            while (capturing && port.isOpen()) {
                // ´¦ÀíÔÝͣ״̬
                if (paused) {
                    buffer.reset(); // Çå¿ÕÀÛ»ýÊý¾Ý
                    // Çå¿Õ´®¿Ú½ÓÊÕ»º³åÇø£¨¶ÁÈ¡²¢¶ªÆú£©
                    int len;
                    do {
                        len = port.readBytes(readBuffer, readBuffer.length);
                    } while (len > 0);
                    // ½µµÍÔÝͣ״̬ϵÄCPUÕ¼ÓÃ
                    try { Thread.sleep(100); } catch (InterruptedException ignore) {}
                    continue;
                }

                // 1. ¼ì²é³¬Ê±²¢·¢ËÍÀÛ»ýÊý¾Ý
                long currentTime = System.currentTimeMillis();
                if (buffer.size() > 0 && (currentTime - lastReceivedTime) >= 20) {
                    onReceived.accept(buffer.toByteArray());
                    buffer.reset();
                }

                // 2. ¶ÁÈ¡ÐÂÊý¾Ý
                int len = port.readBytes(readBuffer, readBuffer.length);
                currentTime = System.currentTimeMillis(); // ¸üе±Ç°Ê±¼ä

                if (len > 0) {
                    // дÈ뻺³åÇø²¢¸üÐÂʱ¼ä´Á
                    buffer.write(readBuffer, 0, len);
                    lastReceivedTime = currentTime;
                }
                
                // 3. ½µµÍCPUÕ¼ÓãºÎÞÊý¾ÝÇÒ»º³åÇø¿Õʱ¶ÌÔÝÐÝÃß
                if (len <= 0 && buffer.size() == 0) {
                    try { Thread.sleep(1); } catch (InterruptedException ignore) {}
                }
            }
            
            // Ï߳̽áÊøÇ°·¢ËÍÊ£ÓàÊý¾Ý
            if (buffer.size() > 0) {
                onReceived.accept(buffer.toByteArray());
            }
        });
        readerThread.setDaemon(true);
        readerThread.start();
    }

    /**
     * Í£Ö¹Êý¾Ý½ÓÊÕÏß³Ì
     */
    public void stopCapture() {
        // ÉèÖò¶»ñ±ê־Ϊ false£¬Í¨ÖªÏß³ÌÍ˳ö
        capturing = false;
        // Èç¹ûÏ̴߳æÔÚ£¬µÈ´ý×î¶à500msÈ·±£Ï߳̽áÊø
        if (readerThread != null) {
            try { readerThread.join(500); } catch (InterruptedException ignore) {}
            // Çå¿ÕÏß³ÌÒýÓÃ
            readerThread = null;
        }
    }

    // ÉèÖÃÔÝͣ״̬
    public void setPaused(boolean paused) {
        this.paused = paused;
    }

    // »ñÈ¡µ±Ç°ÊÇ·ñÔÝÍ£
    public boolean isPaused() {
        return paused;
    }

    // Åжϴ®¿ÚÊÇ·ñÒÑ´ò¿ª
    public boolean isOpen() {
        return port != null && port.isOpen();
    }

    /**
     * ·¢ËÍÊý¾Ý
     * @param data Òª·¢Ë͵Ä×Ö½ÚÊý×é
     * @return ÊÇ·ñ³É¹¦·¢ËÍ
     */
    public boolean send(byte[] data) {
        // Èç¹û´®¿ÚÒѳõʼ»¯ÇÒÒÑ´ò¿ª£¬·¢ËÍÊý¾Ý²¢·µ»Ø½á¹û
        return port != null && port.isOpen() && port.writeBytes(data, data.length) > 0;
    }
}