using System.Collections;
using AibisDream.Framework;
using AibisDream.Kit;
using AibisDream.FixSystem;
using AibisDream.UI;
using UnityEngine.AddressableAssets;
using UnityEngine.ResourceManagement.AsyncOperations;
using UnityEngine.SceneManagement;
using DG.Tweening;

namespace AibisDream
{
    public class SceneLoader : Singleton<SceneLoader>
    {
        #region 场景转换参数
        
        private AsyncOperationHandle _loadHandle;
        private string _sceneToLoad;
        private bool _isLoading;

        private string _currentSceneName;

        public string CurrentSceneName => _currentSceneName;
        public bool IsLoading => _isLoading;

        public override void OnSingletonInit()
        {
        }

        #endregion

        /// <summary>
        /// 同步场景转换
        /// </summary>
        /// <param name="targetScene">目标场景</param>
        public void LoadScene(string targetScene)
        {
            StartCoroutine(LoadSceneAsync(targetScene));
        }

        /// <summary>
        /// 异步场景转换
        /// </summary>
        /// <param name="targetScene">目标场景</param>
        /// <returns></returns>
        public IEnumerator LoadSceneAsync(string targetScene)
        {
            if (_isLoading)
            {
                yield return null;
            }
            else
            {
                // 场景转换参数
                _isLoading = true;
                UIManager.Instance.ShowPreferredLoading();
                _sceneToLoad = targetScene;
                
                // 在卸载场景前清理所有系统
                if (!string.IsNullOrEmpty(_currentSceneName))
                {
                    DOTween.KillAll();
                    
                    if (FixSystemCenter.SystemDic != null)
                    {
                        FixSystemCenter.SystemDic.Clear();
                    }

                    // 释放场景级资源（在卸载场景之前）
                    ResourceSystem.ReleaseSceneLoader();

                    yield return Addressables.UnloadSceneAsync(_loadHandle);
                }

                // 显式创建 Scene Loader（在所有业务组件 Start 之前）
                ResourceSystem.CreateSceneLoader();

                _loadHandle = Addressables.LoadSceneAsync(_sceneToLoad, LoadSceneMode.Additive);
                while (!_loadHandle.IsDone)
                {
                    UIManager.Instance.SetPreferredLoadingProgress(_loadHandle.PercentComplete);
                    yield return null;
                }
                UIManager.Instance.SetPreferredLoadingProgress(1f);

                // 场景加载完成，通知各系统
                EnumEventSystem.Global.Send(EventEnum.SceneLoad, _sceneToLoad);
                _currentSceneName = _sceneToLoad;
                UIManager.Instance.HidePreferredLoading();
                _isLoading = false;
            }
        }

        public IEnumerator UnloadSceneAsync()
        {
            if (_isLoading)
            {
                yield return null;
            }
            else
            {
                _isLoading = true;

                if (_loadHandle.IsValid())
                {
                    DOTween.KillAll();
                    ResourceSystem.ReleaseSceneLoader();

                    yield return Addressables.UnloadSceneAsync(_loadHandle);
                    _currentSceneName = null;
                }

                _isLoading = false;
            }
        }
    }

}