import * as plugins from './plugins.js';
import * as pluginsTyped from './plugins.typed.js';

export interface IAssetVariation {
  format?: 'avif' | 'webp' | 'png';
  width?: number;
  height?: number;
  invert?: boolean;
}

export interface ISmartJimpOptions {
  mode: 'sharp' | 'jimp';
}

export class SmartJimp {
  public levelCache = new plugins.levelcache.LevelCache({
    cacheId: 'mastercache',
    maxMemoryStorageInMB: 100,
    maxDiskStorageInMB: 5000,
  });

  public options: ISmartJimpOptions;
  constructor(optionsArg: ISmartJimpOptions) {
    this.options = optionsArg;
  }

  /**
   * get a key that is unique for a wanted asset variation
   */
  private getCacheKey(
    sourceTypeArg: 'streamfile' | 'smartfile',
    sourceIdArg: string,
    assetVariationArg?: IAssetVariation
  ) {
    return `${sourceTypeArg}_${sourceIdArg}_${
      assetVariationArg
        ? `${assetVariationArg.width || 'auto'}x${assetVariationArg.height || 'auto'}`
        : 'original'
    }`;
  }

  sharpMod: typeof pluginsTyped.sharpType.default;
  public async getSharpMod(): Promise<
    typeof pluginsTyped.sharpType.default
  > {
    if (!this.sharpMod) {
      this.sharpMod = (await import('sharp')).default;
    }
    return this.sharpMod;
  }

  jimpMod: typeof pluginsTyped.jimpType;
  public async getJimpMod(): Promise<typeof pluginsTyped.jimpType.default> {
    if (!this.jimpMod) {
      this.jimpMod = await import('jimp');
    }
    return this.jimpMod.default;
  }

  public async computeAssetVariation(assetBufferArg: Buffer, assetVariationArg: IAssetVariation) {
    if (this.options.mode === 'sharp') {
      const sharp = await this.getSharpMod();
      if (!assetVariationArg) {
        return assetBufferArg;
      }
      let sharpImage = sharp(assetBufferArg);
      sharpImage = sharpImage.resize(assetVariationArg.width, assetVariationArg.height);
      const resultResize = sharpImage.resize(assetVariationArg.width, assetVariationArg.height);
      if (assetVariationArg.invert) {
        // TODO: implement invert
      }
      switch (assetVariationArg.format) {
        case 'avif':
          sharpImage = resultResize.avif();
        case 'webp':
          sharpImage = resultResize.webp();
        case 'png':
          sharpImage = resultResize.png();
      }
      return sharpImage.toBuffer();
    } else if (this.options.mode === 'jimp') {
      const jimp = await this.getJimpMod();
      let jimpImage = await jimp.read(assetBufferArg);
      if (assetVariationArg.width || assetVariationArg.height) {
        jimpImage = jimpImage.resize(assetVariationArg.width, assetVariationArg.height);
      }
      if (assetVariationArg.invert) {
        jimpImage = jimpImage.invert();
      }
      switch (assetVariationArg.format) {
        case 'png':
          return await jimpImage.getBufferAsync(jimp.MIME_PNG);
        default:
          return await jimpImage.getBufferAsync(jimp.MIME_JPEG);
      }
    }
  }

  public async getFromSmartfile(
    smartfileArg: plugins.smartfile.SmartFile,
    wantedDimensionsArg?: IAssetVariation
  ) {
    const cacheKey = this.getCacheKey(
      'smartfile',
      await smartfileArg.getHash(),
      wantedDimensionsArg
    );
    const existingCacheEntry = await this.levelCache.retrieveCacheEntryByKey(cacheKey);
    if (existingCacheEntry) {
      return existingCacheEntry.contents;
    } else {
      const computedAssetBuffer = await this.computeAssetVariation(
        smartfileArg.contentBuffer,
        wantedDimensionsArg
      );
      this.levelCache.storeCacheEntryByKey(
        cacheKey,
        new plugins.levelcache.CacheEntry({
          contents: computedAssetBuffer,
          ttl: 600000,
        })
      );
      return computedAssetBuffer;
    }
  }

  public async createAvifImageFromBuffer(bufferArg: Buffer) {
    const sharp = await this.getSharpMod();
    const sharpImage = sharp(bufferArg);
    const result = await sharpImage.avif().toBuffer();
    return result;
  }
}