import { BUNDLE_ID } from '@scripts/define/ResDefine';
import { Asset, assetManager, AssetManager, ImageAsset, path, Prefab, Sprite, SpriteFrame, Texture2D } from 'cc';

export enum ResourceScope {
  App = 'app',
  Scene = 'scene',
  View = 'view',
}

interface RemoteRes<T> {
  url: string,
  asset?: T,
  task?: Promise<Asset>;
}

interface ResLoader<T> {
  asset: T,

}

export class ResourceManager {
  private readonly bundles = new Map<string, AssetManager.Bundle>();
  private readonly remotes = new Map<string, RemoteRes<Asset>>();
  private readonly loaders = new Map<string, Promise<Asset>>();

  private getLoaderKey(bundleName: string, path: string, typeName: string) {
    return `Bundle:${bundleName}-path:${path}-type:${typeName}`;
  }

  private async getResLoading<T extends Asset>(key: string): Promise<T> {
    if (this.loaders.has(key)) {
      const res = await this.loaders.get(key);
      return res as T;
    }
  }

  async loadBundle(name: string): Promise<AssetManager.Bundle> {
    const cached = this.bundles.get(name) ?? assetManager.getBundle(name);
    if (cached) {
      this.bundles.set(name, cached);
      return cached;
    }

    return new Promise((resolve, reject) => {
      assetManager.loadBundle(name, (error, bundle) => {
        if (error || !bundle) {
          reject(error ?? new Error(`Bundle not found: ${name}`));
          return;
        }
        this.bundles.set(name, bundle);
        resolve(bundle);
      });
    });
  }

  private async onLoad<T extends Asset>(key: string, loader: Promise<T>) {
    this.loaders.set(key, loader);
    try {
      const res = await loader;
      this.loaders.delete(key);
      return res as T;
    } catch {
      this.loaders.delete(key);
      return null;
    }
  }

  async load<T extends Asset>(bundleName: string, path: string, type: new (...args: never[]) => T): Promise<T> {
    const key = this.getLoaderKey(bundleName, path, type.name);
    if (this.loaders.has(key)) {
      const res = await this.loaders.get(key);
      return res as T;
    }

    const bundle = await this.loadBundle(bundleName);
    const loader = new Promise<T>((resolve, reject) => {
      bundle.load<T>(path, type, (error, asset) => {
        if (error || !asset) {
          console.log(`asset load error!! file:${bundleName}/${path} error:${error}`);
          resolve(null);
          return;
        }
        resolve(asset);
      });
    });

    return await this.onLoad<T>(key, loader);
  }

  loadPrefab(bundleName: string, path: string): Promise<Prefab> {
    return this.load(bundleName, path, Prefab);
  }

  releaseBundle(name: string): void {
    const bundle = this.bundles.get(name);
    if (!bundle) return;
    bundle.releaseAll();
    assetManager.removeBundle(bundle);
    this.bundles.delete(name);
  }

  async loadRemoteSp(url: string): Promise<SpriteFrame | null> {
    const key = this.getLoaderKey("RemoteAsset", url, "SpriteFrame");
    if (this.remotes.has(key)) {
      const res = this.remotes.get(key);
      if (res.task) {
        await res.task;
      }
      return res.asset as SpriteFrame;
    }

    const cache: RemoteRes<SpriteFrame> = { url };
    cache.task = this.loadRemoteRes<ImageAsset>(url, "ImageAsset");
    this.remotes.set(key, cache);

    const img = await cache.task;
    if (!img) {
      this.remotes.delete(key);
      return null;
    }

    const sp = SpriteFrame.createWithImage(img as ImageAsset);
    sp.packable = false;
    cache.asset = sp;
    delete cache.task;
    sp["_cacheKey"] = key;
    return sp;
  }

  async loadRemoteRes<T extends Asset>(url: string, type: string): Promise<T | null> {
    const key = this.getLoaderKey("RemoteAsset", url, type);
    if (this.loaders.has(key)) {
      const res = await this.loaders.get(key);
      return res as T;
    }

    const loader = new Promise<T>((resolve, reject) => {
      assetManager.loadRemote<T>(url, (err, res) => {
        if (err) {
          console.error(err, url);
          resolve(null);
          return;
        }
        resolve(res);
      });
    })

    return await this.onLoad<T>(key, loader);
  }

  async releaseRes(res: Asset) {
    res.decRef();

    const cacheKey: string = res["_cacheKey"];
    if (cacheKey && this.remotes.has(cacheKey)) {
      const cache = this.remotes.get(cacheKey);
      const refCount = cache.asset.refCount;
      if (refCount === 0) {
        // if (cache.asset) {
        //   if (cache.asset instanceof SpriteFrame) {
        //     const texture = cache.asset.texture as Texture2D;
        //     const image = texture.image;
        //     image.destroy();
        //     texture.destroy()
        //   }
        //   cache.asset.destroy();
        // }
        this.remotes.delete(cacheKey);
      }
    }
  }
}