package com.example.livestreaming;

import android.os.Bundle;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.media3.common.MediaItem;
import androidx.media3.common.PlaybackException;
import androidx.media3.common.Player;
import androidx.media3.exoplayer.ExoPlayer;

import com.example.livestreaming.databinding.ActivityPlayerBinding;

public class PlayerActivity extends AppCompatActivity {

    public static final String EXTRA_PLAY_URL = "extra_play_url";
    public static final String EXTRA_TITLE = "extra_title";

    private ActivityPlayerBinding binding;
    private ExoPlayer player;
    private boolean triedAltUrl = false;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = ActivityPlayerBinding.inflate(getLayoutInflater());
        setContentView(binding.getRoot());

        String t = getIntent().getStringExtra(EXTRA_TITLE);
        setTitle(t != null ? t : "Live");
    }

    @Override
    protected void onStart() {
        super.onStart();
        String url = getIntent().getStringExtra(EXTRA_PLAY_URL);
        if (url == null || url.trim().isEmpty()) return;

        triedAltUrl = false;

        // 创建低延迟播放器配置
        ExoPlayer exo = new ExoPlayer.Builder(this)
                .setLoadControl(new androidx.media3.exoplayer.DefaultLoadControl.Builder()
                        // 减少缓冲区大小，降低延迟
                        .setBufferDurationsMs(
                                1000,    // 最小缓冲时长 1秒
                                3000,    // 最大缓冲时长 3秒  
                                500,     // 播放缓冲时长 0.5秒
                                1000     // 播放后缓冲时长 1秒
                        )
                        .build())
                .build();
        
        // 设置播放器视图
        binding.playerView.setPlayer(exo);
        
        // 启用低延迟模式
        binding.playerView.setUseController(true);
        binding.playerView.setControllerAutoShow(false);

        String altUrl = getAltHlsUrl(url);
        exo.addListener(new Player.Listener() {
            @Override
            public void onPlayerError(PlaybackException error) {
                if (triedAltUrl) return;
                if (altUrl == null || altUrl.trim().isEmpty()) return;
                triedAltUrl = true;

                exo.setMediaItem(MediaItem.fromUri(altUrl));
                exo.prepare();
                exo.setPlayWhenReady(true);
            }
        });

        exo.setMediaItem(MediaItem.fromUri(url));
        exo.prepare();
        exo.setPlayWhenReady(true);
        player = exo;
    }

    @Override
    protected void onStop() {
        super.onStop();
        if (player != null) {
            player.release();
            player = null;
        }
    }

    private String getAltHlsUrl(String url) {
        if (!url.endsWith(".m3u8")) return null;
        if (url.contains("/index.m3u8")) return null;

        return url.substring(0, url.length() - ".m3u8".length()) + "/index.m3u8";
    }
}