using System;
using System.Collections.Generic;
using GameFramework.Resource;
using GeometryTD.CustomUtility;
using UnityEngine;
using UnityGameFramework.Runtime;

namespace GeometryTD.CustomComponent
{
    public class SpriteCacheComponent : GameFrameworkComponent
    {
        [SerializeField] private float _pixelsPerUnit = 100f;
        [SerializeField] private Vector2 _defaultPivot = new(0.5f, 0.5f);

        private Dictionary<string, Sprite> _spriteCache;
        private Dictionary<string, List<Action<Sprite>>> _pendingCallbacks;
        private ResourceComponent _resource;

        void Start()
        {
            _spriteCache = new Dictionary<string, Sprite>();
            _pendingCallbacks = new Dictionary<string, List<Action<Sprite>>>();
            _resource = GameEntry.Resource;
        }

        public void GetSprite(string assetName, Action<Sprite> callback)
        {
            if (_spriteCache.TryGetValue(assetName, out var sprite))
            {
                callback?.Invoke(sprite);
                return;
            }

            if (_pendingCallbacks.TryGetValue(assetName, out var pendingList))
            {
                pendingList.Add(callback);
                return;
            }

            _pendingCallbacks[assetName] = new List<Action<Sprite>> { callback };
            _resource.LoadAsset
            (
                AssetUtility.GetTextureAsset(assetName),
                Constant.AssetPriority.UIFormAsset,
                new LoadAssetCallbacks(
                    (resourcePath, asset, duration, userData) =>
                    {
                        Log.Debug(resourcePath);
                        Texture2D texture = asset as Texture2D;
                        Sprite loadedSprite = null;

                        if (texture != null)
                        {
                            loadedSprite = Sprite.Create(
                                texture,
                                new Rect(0, 0, texture.width, texture.height),
                                _defaultPivot,
                                _pixelsPerUnit);

                            _spriteCache[assetName] = loadedSprite;
                        }

                        if (_pendingCallbacks.TryGetValue(assetName, out var callbacks))
                        {
                            _pendingCallbacks.Remove(assetName);
                            for (int i = 0; i < callbacks.Count; i++)
                            {
                                callbacks[i]?.Invoke(loadedSprite);
                            }
                        }
                    },
                    (resourcePath, status, errorMessage, userData) =>
                    {
                        Log.Error("Can not load icon '{0}' from '{1}' with error message '{2}'.",
                            assetName,
                            resourcePath,
                            errorMessage);

                        if (_pendingCallbacks.TryGetValue(assetName, out var callbacks))
                        {
                            _pendingCallbacks.Remove(assetName);
                            for (int i = 0; i < callbacks.Count; i++)
                            {
                                callbacks[i]?.Invoke(null);
                            }
                        }
                    }
                )
            );
        }

        private void OnDestroy()
        {
            _spriteCache.Clear();
            _pendingCallbacks.Clear();
            _resource = null;
        }
    }
}