package homein;

import java.io.File;
import java.io.IOException;
import java.nio.channels.FileChannel;
import java.nio.channels.FileLock;
import java.nio.file.StandardOpenOption;

public class WenJianSuo {
    private static FileLock lock;
    private static FileChannel channel;
    private static final String LOCK_FILE_NAME = "homein.lock";
    
    // 检查程序是否已经运行
    public static boolean isAlreadyRunning() {
        try {
            File lockFile = new File(LOCK_FILE_NAME);
            channel = FileChannel.open(lockFile.toPath(), 
                StandardOpenOption.CREATE, StandardOpenOption.WRITE);
            lock = channel.tryLock();
            
            // 如果获取不到锁，说明程序已经在运行
            return lock == null;
        } catch (IOException e) {
            return true; // 发生异常也认为程序已在运行
        }
    }
    
    // 释放文件锁
    public static void releaseLock() {
        try {
            if (lock != null) {
                lock.release();
            }
            if (channel != null) {
                channel.close();
            }
            // 删除锁文件
            File lockFile = new File(LOCK_FILE_NAME);
            if (lockFile.exists()) {
                lockFile.delete();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}