using System.Collections;
using UnityEngine;
using BaseGames.Core;
using BaseGames.Core.Events;

namespace BaseGames.Player
{
    /// <summary>
    /// 监听 EVT_CheckpointRespawn，将玩家瞬移至最近检查点坐标。
    /// 通过淡出 → 移位 → 淡入实现无视觉跳变的传送。
    ///
    /// 挂载在玩家根节点（与 Rigidbody2D 同一 GameObject）。
    /// </summary>
    public class CheckpointRespawnHandler : MonoBehaviour
    {
        [Header("事件 - 监听")]
        [Tooltip("EVT_CheckpointRespawn — 由 LethalTrap 在玩家存活且场景有检查点时触发")]
        [SerializeField] private VoidEventChannelSO _onCheckpointRespawn;

        [Header("事件 - 触发")]
        [Tooltip("EVT_FadeOutRequest — 传送前淡出屏幕")]
        [SerializeField] private VoidEventChannelSO _onFadeOutRequest;

        [Tooltip("EVT_FadeInRequest — 传送后淡入屏幕")]
        [SerializeField] private VoidEventChannelSO _onFadeInRequest;

        [Header("配置")]
        [Tooltip("淡出结束到执行位移之间的等待时长（秒，不受 TimeScale 影响）")]
        [SerializeField] private float _fadeHalfDuration = 0.2f;

        private readonly CompositeDisposable _subs = new();

        private void OnEnable()  => _onCheckpointRespawn?.Subscribe(OnCheckpointRespawn).AddTo(_subs);
        private void OnDisable() => _subs.Clear();

        private void OnCheckpointRespawn() => StartCoroutine(RespawnCoroutine());

        private IEnumerator RespawnCoroutine()
        {
            _onFadeOutRequest?.Raise();
            yield return new WaitForSecondsRealtime(_fadeHalfDuration);

            var svc = ServiceLocator.GetOrDefault<ICheckpointService>();
            if (svc != null && svc.HasCheckpoint)
            {
                // 清零速度后移位，防止物理残留动量导致滑步
                var rb = GetComponent<Rigidbody2D>();
                if (rb != null)
                {
                    rb.velocity = Vector2.zero;
                    rb.position       = svc.CheckpointPosition;
                }
                else
                {
                    transform.position = svc.CheckpointPosition;
                }
            }

            _onFadeInRequest?.Raise();
        }
    }
}