web/src/decrypt/raw.ts

import { AudioMimeType, GetArrayBuffer, GetCoverFromFile, GetMetaFromFile, SniffAudioExt } from '@/decrypt/utils';

import { DecryptResult } from '@/decrypt/entity';

import { parseBlob as metaParseBlob } from 'music-metadata-browser';

export async function Decrypt(
  file: Blob,
  raw_filename: string,
  raw_ext: string,
  detect: boolean = true,
): Promise<DecryptResult> {
  let ext = raw_ext;
  if (detect) {
    const buffer = new Uint8Array(await GetArrayBuffer(file));
    ext = SniffAudioExt(buffer, raw_ext);
    if (ext !== raw_ext) file = new Blob([buffer], { type: AudioMimeType[ext] });
  }
  const tag = await metaParseBlob(file);
  const { title, artist } = GetMetaFromFile(raw_filename, tag.common.title, tag.common.artist);

  return {
    title,
    artist,
    ext,
    album: tag.common.album,
    picture: GetCoverFromFile(tag),
    file: URL.createObjectURL(file),
    blob: file,
    mime: AudioMimeType[ext],
  };
}