using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using UnityEngine;
using UnityEngine.ResourceManagement.ResourceProviders;

namespace DDD
{
    public enum SceneType
    {
        Entry = 0,
        Restaurant = 1,
        Voyage = 2
    }
    
    public class SceneManager : Singleton<SceneManager>, IManager
    {
        [SerializeField]
        private SceneTransitionHandlerSo _sceneTransitionHandlerSo;
        
        private Dictionary<SceneType, SceneInstance> _loadedScenes;
        
        private SceneInstance _currentSceneInstance;
        public Action<SceneInstance> OnSceneChanged;

        public void PreInit()
        {
            Array sceneTypeArray = Enum.GetValues(typeof(SceneType));
            _loadedScenes = new Dictionary<SceneType, SceneInstance>(sceneTypeArray.Length);
        }

        public async Task Init()
        {
            try
            {
                foreach (SceneType sceneType in Enum.GetValues(typeof(SceneType)))
                {
                    if (sceneType == SceneType.Entry) continue;
            
                    await PreloadSceneAsync(sceneType);
                }
            }
            catch (Exception e)
            {
                Debug.LogWarning($"Scene preload failed\n{e}");
            }
        }

        public void PostInit()
        {
            
        }
        
        public SceneInstance GetSceneInstance(SceneType sceneType) => _loadedScenes[sceneType];
        
        public async Task PreloadSceneAsync(SceneType sceneType)
        {
            if (_loadedScenes.ContainsKey(sceneType))
                return;

            string key = sceneType.ToString();
            SceneInstance sceneInstance = await AssetManager.LoadScene(key);
            
            if (sceneInstance.Scene.IsValid())
            {
                _loadedScenes[sceneType] = sceneInstance;

                foreach (var root in sceneInstance.Scene.GetRootGameObjects())
                {
                    root.SetActive(false);
                }
            }
            else
            {
                Debug.LogError($"[SceneManager] Failed to preload scene: {sceneType}");
            }
        }
        
        public async Task ActivateScene(SceneType sceneType)
        {
            foreach (var handler in _sceneTransitionHandlerSo.Handlers.Where(handler => handler != null))
            {
                await handler.OnBeforeSceneActivate(sceneType);
            }
            
            if (_loadedScenes.TryGetValue(sceneType, out var sceneInstance))
            {
                foreach (var root in sceneInstance.Scene.GetRootGameObjects())
                {
                    root.SetActive(true);
                }

                UnityEngine.SceneManagement.SceneManager.SetActiveScene(sceneInstance.Scene);
                _currentSceneInstance = sceneInstance;
            }
            else
            {
                Debug.LogError($"[SceneManager] Scene not loaded: {sceneType}");
            }
            
            foreach (var handler in _sceneTransitionHandlerSo.Handlers.Where(handler => handler != null))
            {
                await handler.OnAfterSceneActivate(sceneType);
            }
        }

        public void DeactivateScene(SceneType sceneType)
        {
            if (_loadedScenes.TryGetValue(sceneType, out var sceneInstance))
            {
                foreach (var root in sceneInstance.Scene.GetRootGameObjects())
                {
                    root.SetActive(false);
                }
            }
        }

        public async Task UnloadSceneAsync(SceneType sceneType)
        {
            if (_loadedScenes.TryGetValue(sceneType, out var sceneInstance))
            {
                await AssetManager.UnloadScene(GetSceneInstance(sceneType));
            }
        }
    }
}