using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Video;

public class VideoPlayerPool
{
    private static VideoPlayerPool _instance;
    public static VideoPlayerPool Instance => _instance ??= new VideoPlayerPool();

    private readonly Queue<VideoPlayer> pool = new Queue<VideoPlayer>();
    private GameObject parent;
    private int maxCount = 5;

    // 已经分配出去的播放器（方便管理）
    private readonly HashSet<VideoPlayer> inUsePlayers = new HashSet<VideoPlayer>();

    private VideoPlayerPool()
    {
    }

    public void Init(GameObject parentObj, int maxPoolCount)
    {
        parent = parentObj;
        maxCount = maxPoolCount;

        // 先清理旧的
        foreach (var player in pool)
        {
            if (player != null) GameObject.Destroy(player.gameObject);
        }

        pool.Clear();
        inUsePlayers.Clear();

        // 创建初始播放器
        for (int i = 0; i < maxCount; i++)
        {
            var go = new GameObject($"VideoPlayer_{i}");
            go.transform.SetParent(parent.transform);
            var player = go.AddComponent<VideoPlayer>();

            player.playOnAwake = false;
            player.renderMode = VideoRenderMode.RenderTexture;

            pool.Enqueue(player);
        }
    }

    // 获取播放器
    public VideoPlayer GetPlayer()
    {
        Debug.Log($"[VideoPlayerPool] GetPlayer VideoPlayerPool===={pool.Count}");

        if (pool.Count == 0)
        {
            Debug.LogWarning("VideoPlayerPool空了，无法分配更多播放器");
            return null;
        }

        var player = pool.Dequeue();
        inUsePlayers.Add(player);
        player.gameObject.SetActive(true);
        return player;
    }

    // 归还播放器
    public void ReturnPlayer(VideoPlayer player)
    {
        if (player == null) return;

        if (inUsePlayers.Contains(player))
        {
            player.Stop();
            player.clip = null;

            if (player.targetTexture != null)
            {
                player.targetTexture.Release();
                GameObject.Destroy(player.targetTexture);
                player.targetTexture = null;
            }

            player.gameObject.SetActive(false);
            inUsePlayers.Remove(player);
            pool.Enqueue(player);
        }
        else
        {
            Debug.LogWarning("尝试归还未被分配的播放器");
        }
    }

    // 释放所有
    public void DisposeAll()
    {
        foreach (var player in pool)
        {
            if (player != null) GameObject.Destroy(player.gameObject);
        }

        foreach (var player in inUsePlayers)
        {
            if (player != null) GameObject.Destroy(player.gameObject);
        }

        pool.Clear();
        inUsePlayers.Clear();
    }
}