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

namespace BaseGames.Core
{
    /// <summary>
    /// 死亡/复活流程服务接口。
    /// </summary>
    public interface IDeathRespawnService
    {
        /// <summary>玩家死亡时由 GameManager 调用，启动死亡演出流程。</summary>
        IEnumerator StartDeathSequenceCoroutine();

        /// <summary>DeathScreen 确认按钮点击后调用，执行复活流程。</summary>
        IEnumerator StartRespawnCoroutine();

        /// <summary>SteelSoul 模式：HP 归零后直接清档并返回主菜单。</summary>
        IEnumerator StartGameOverCoroutine();
    }

    /// <summary>
    /// 死亡/复活流程独立服务（Phase 0 骨架，Phase 1 完整实现）。
    /// </summary>
    public class DeathRespawnService : MonoBehaviour, IDeathRespawnService
    {
        [Header("Config")]
        [SerializeField] private float _deathAnimDuration   = 1.2f;
        [SerializeField] private float _deathScreenDelay    = 0.5f;
        [SerializeField] private float _respawnFadeDuration = 0.4f;

        [Header("Event Channels - Raise")]
        [SerializeField] private VoidEventChannelSO _onRespawnStarted;
        [SerializeField] private VoidEventChannelSO _onRespawnCompleted;

        [Header("Event Channels - Listen")]
        [SerializeField] private VoidEventChannelSO _onDeathScreenConfirmed;

        private bool _deathConfirmed;

        private void OnEnable()
        {
            if (_onDeathScreenConfirmed != null)
                _onDeathScreenConfirmed.OnEventRaised += HandleDeathScreenConfirmed;
        }

        private void OnDisable()
        {
            if (_onDeathScreenConfirmed != null)
                _onDeathScreenConfirmed.OnEventRaised -= HandleDeathScreenConfirmed;
        }

        private void HandleDeathScreenConfirmed() => _deathConfirmed = true;

        public IEnumerator StartDeathSequenceCoroutine()
        {
            yield return new WaitForSeconds(_deathAnimDuration);
            yield return new WaitForSeconds(_deathScreenDelay);
            _deathConfirmed = false;
            yield return new WaitUntil(() => _deathConfirmed);
        }

        public IEnumerator StartRespawnCoroutine()
        {
            _onRespawnStarted?.Raise();
            yield return new WaitForSeconds(_respawnFadeDuration);
            // Phase 1：加载存档场景（TODO）
            yield return new WaitForSeconds(_respawnFadeDuration);
            _onRespawnCompleted?.Raise();
        }

        public IEnumerator StartGameOverCoroutine()
        {
            // Phase 1：SteelSoul 清档并返回主菜单（TODO）
            yield return null;
        }
    }
}