using System.Collections.Generic;
using SLSUtilities.General;
using UnityEngine;

namespace SLSUtilities.Feedback
{
    /// <summary>
    /// 全局 Feedback 播放管理器（Singleton）。
    /// 集中驱动所有注册的 FeedbackPlayer，提供 Play / Stop 快捷 API。
    /// 适用于不绑定特定角色时间缩放的"全局反馈"（如后处理效果、UI 反馈等）。
    /// 需要角色级时间缩放的反馈仍由 FeedbackSubcontroller 手动驱动。
    /// </summary>
    public class FeedbackManager : Singleton<FeedbackManager>
    {
        private const int INITIAL_CAPACITY = 64;

        private readonly List<FeedbackPlayer> _activePlayers = new List<FeedbackPlayer>(INITIAL_CAPACITY);

        /// <summary>
        /// 当前活跃的 Player 数量。
        /// </summary>
        public int ActiveCount => _activePlayers.Count;

        /// <summary>
        /// 以全局方式播放一个 FeedbackData，不绑定任何 owner 或 timeProvider。
        /// </summary>
        public FeedbackPlayer Play(FeedbackData data)
        {
            return Play(data, null, null);
        }

        /// <summary>
        /// 播放一个 FeedbackData，指定时间提供者和 owner。
        /// </summary>
        public FeedbackPlayer Play(FeedbackData data, IFeedbackTimeProvider timeProvider, Transform owner)
        {
            if (data == null)
            {
                Debug.LogWarning("[FeedbackManager] Cannot play: FeedbackData is null.");
                return null;
            }

            var player = new FeedbackPlayer(data, timeProvider, owner);
            player.Play();
            _activePlayers.Add(player);
            return player;
        }

        /// <summary>
        /// 注册一个已有的 FeedbackPlayer 由管理器驱动。
        /// 适用于外部创建 Player 后需要交给管理器集中管理的场景。
        /// </summary>
        public void Register(FeedbackPlayer player)
        {
            if (player == null || _activePlayers.Contains(player)) return;
            _activePlayers.Add(player);
        }

        /// <summary>
        /// 停止并移除指定的 FeedbackPlayer。
        /// </summary>
        public void Stop(FeedbackPlayer player)
        {
            if (player == null) return;

            player.Stop();
            _activePlayers.Remove(player);
        }

        /// <summary>
        /// 停止所有活跃的 FeedbackPlayer。
        /// </summary>
        public void StopAll()
        {
            for (int i = _activePlayers.Count - 1; i >= 0; i--)
            {
                _activePlayers[i].Stop();
            }
            _activePlayers.Clear();
        }

        private void Update()
        {
            float dt = Time.unscaledDeltaTime;

            for (int i = _activePlayers.Count - 1; i >= 0; i--)
            {
                FeedbackPlayer player = _activePlayers[i];
                player.Tick(dt);

                if (player.IsCompleted || !player.IsActive)
                {
                    _activePlayers.RemoveAt(i);
                }
            }
        }
    }
}