package com.ard.work.sdk.zlxd.record;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import java.io.*;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.TimeUnit;

@Slf4j
@Component
public class RtspToMP4 {

    private Process process;
    private Thread logThread;
    private volatile boolean running = false;

    /**
     * 开始录制
     *
     * @param streamUrl rtsp地址
     * @param filePath 输出路径
     * @param maxFileSizeBytes 最大文件大小(可传null)
     * @param maxDurationSec 最大录制秒(可传null)
     */
    public synchronized void start(String streamUrl, String filePath, Long maxFileSizeBytes, Integer maxDurationSec) {

        if (running) {
            log.warn("录制已在运行中");
            return;
        }

        try {
            List<String> command = new ArrayList<>();

            command.add("ffmpeg");
            command.add("-rtsp_transport");
            command.add("tcp");
            command.add("-y");
            command.add("-i");
            command.add(streamUrl);

            // 视频直接copy（CPU最低）
            command.add("-c:v");
            command.add("copy");

            // 禁止音频（避免pcm_mulaw问题）
            command.add("-an");

            // 最大文件大小限制
            if (maxFileSizeBytes != null) {
                command.add("-fs");
                command.add(String.valueOf(maxFileSizeBytes));
            }

            // 最大时长限制
            if (maxDurationSec != null) {
                command.add("-t");
                command.add(String.valueOf(maxDurationSec));
            }

            // MP4优化（避免损坏）
            command.add("-movflags");
            command.add("faststart");

            command.add(filePath);

            log.info("启动FFmpeg：{}", command);

            ProcessBuilder pb = new ProcessBuilder(command);
            pb.redirectErrorStream(true);

            process = pb.start();
            running = true;

            startLogThread(process.getInputStream());

            // 等待进程结束（异步）
            new Thread(() -> {
                try {
                    int exitCode = process.waitFor();
                    log.info("FFmpeg退出，code={}", exitCode);
                } catch (Exception e) {
                    log.error("等待进程异常", e);
                } finally {
                    running = false;
                    process = null;
                }
            }).start();

        } catch (Exception e) {
            running = false;
            log.error("启动录制失败", e);
        }
    }

    /**
     * 停止录制（优雅停止）
     */
    public synchronized void stop() {

        if (!running || process == null) {
            log.warn("录制未运行");
            return;
        }

        log.info("开始停止录制...");

        try {
            // 发送q优雅退出
            OutputStream os = process.getOutputStream();
            os.write('q');
            os.flush();
            os.close();

            // 等待3秒
            if (!process.waitFor(3, TimeUnit.SECONDS)) {
                log.warn("FFmpeg未退出，强制关闭");
                process.destroy();

                if (!process.waitFor(1, TimeUnit.SECONDS)) {
                    process.destroyForcibly();
                }
            }

        } catch (Exception e) {
            log.error("停止录制异常", e);
            process.destroyForcibly();
        } finally {
            running = false;
            process = null;
        }

        // 停止日志线程
        if (logThread != null && logThread.isAlive()) {
            logThread.interrupt();
        }

        log.info("录制已停止");
    }

    /**
     * 是否运行
     */
    public boolean isRunning() {
        return running;
    }

    /**
     * 启动日志线程
     */
    private void startLogThread(InputStream inputStream) {

        logThread = new Thread(() -> {
            try (BufferedReader br =
                         new BufferedReader(new InputStreamReader(inputStream))) {

                String line;
                while ((line = br.readLine()) != null && running) {
                    log.debug("FFmpeg: {}", line);
                }

            } catch (Exception e) {
                if (running) {
                    log.error("日志线程异常", e);
                }
            }
        });

        logThread.setDaemon(true);
        logThread.start();
    }
}