import sharp from 'sharp';
import { rgbaToThumbHash } from 'thumbhash';

const FULL_MAX = 1000;
const THUMB_MAX = 200;

export default async function processAvifImage(inputBuffer) {
  const input = Buffer.isBuffer(inputBuffer)
    ? inputBuffer
    : Buffer.from(inputBuffer);

  const meta = await sharp(input).metadata();
  const w = meta.width ?? 0;
  const h = meta.height ?? 0;
  const isAvif =
    meta.format === 'avif' ||
    (meta.format === 'heif' && meta.compression === 'av1');
  const useOriginalFull =
    isAvif && w > 0 && h > 0 && w <= FULL_MAX && h <= FULL_MAX;

  if (!useOriginalFull) {
    console.log(
      `processAvifImage: converting full image (format=${meta.format ?? 'unknown'}, ${w}×${h}, avif=${isAvif})`,
    );
  }

  const thumbPipeline = sharp(input)
    .resize(THUMB_MAX, THUMB_MAX, { fit: 'inside', withoutEnlargement: true });

  const [full, thumb, thumbRgba] = await Promise.all([
    useOriginalFull
      ? Promise.resolve({
          info: { width: w, height: h },
          data: input,
        })
      : sharp(input)
          .resize(FULL_MAX, FULL_MAX, { fit: 'inside', withoutEnlargement: true })
          .avif({ effort: 4 })
          .toBuffer({ resolveWithObject: true }),
    thumbPipeline.clone().avif({ effort: 4 }).toBuffer({ resolveWithObject: true }),
    thumbPipeline
      .clone()
      .resize(100, 100, { fit: 'inside', withoutEnlargement: true })
      .ensureAlpha()
      .raw()
      .toBuffer({ resolveWithObject: true }),
  ]);

  const thumbHashBytes = rgbaToThumbHash(
    thumbRgba.info.width,
    thumbRgba.info.height,
    thumbRgba.data,
  );

  return {
    full: {
      w: full.info.width,
      h: full.info.height,
      size: full.data.length,
      buffer: full.data,
    },
    thumb: {
      w: thumb.info.width,
      h: thumb.info.height,
      size: thumb.data.length,
      buffer: thumb.data,
      hash: Buffer.from(thumbHashBytes).toString('base64'),
    },
  };
}