using System.Collections;
using System.Collections.Generic;
using Convention;
using UnityEngine;

namespace Demo.Game
{
    public class SkyUpdatement : Updatement<int>, IAssetBundleLoader
    {
        public static SkyUpdatement Make()
        {
            return new GameObject().AddComponent<SkyUpdatement>();
        }

        private readonly Dictionary<string, int> NameCache = new();
        private readonly Dictionary<int, Material> MaterialCache = new();

        public string SkyAssetBundlePath;
        public AssetBundle SkyAssetBundle;

        protected override int Lerp(int begin, int end, float t)
        {
            return begin;
        }

        [Content, SerializeField] private int Cache;

        protected override void UpdateData(int data)
        {
            if (string.IsNullOrEmpty(SkyAssetBundlePath))
                return;
            if (Cache < 0)
                return;
            if (Cache != data)
            {
                RenderSettings.skybox = MaterialCache[data];
                Cache = data;
            }
        }

        public override IEnumerator UnloadScript()
        {
            Cache = -1;
            if (string.IsNullOrEmpty(SkyAssetBundlePath) == false)
                yield return this.UnloadAssetBundle(SkyAssetBundlePath);
            SkyAssetBundlePath = "";
            yield return base.UnloadScript();
        }

        /// <summary>
        /// 对应ab包名称，自动匹配对应平台
        /// </summary>
        /// <param name="ab"></param>
        [Convention.RScript.Variable.Attr.Method]
        public IEnumerator Load(string ab)
        {
            yield return this.LoadAssetBundle(ab, x =>
            {
                SkyAssetBundlePath = ab;
                SkyAssetBundle = x;
            });
        }

        /// <summary>
        /// 在指定时刻切换天空
        /// </summary>
        /// <param name="time"></param>
        /// <param name="sky"></param>
        [Convention.RScript.Variable.Attr.Method]
        public IEnumerator Add(float time, string sky)
        {
            var ir = SkyAssetBundle.LoadAssetAsync<Material>(sky);
            ir.completed += delegate
            {
                var mat = ir.asset as Material;
                if (NameCache.TryGetValue(sky, out int id) == false)
                {
                    id = NameCache.Count;
                    NameCache[sky] = id;
                }
                MaterialCache[id] = mat;
                ManualAddEntry(time, id, default);
            };
            yield return ir;
        }
    }
}