const { makeTorrent, extractWebseed } = require('../src/torrent');

describe('makeTorrent + extractWebseed round-trip', () => {
  it('extracts the webseed URL back from a generated torrent', () => {
    const url = 'http://example.com/stream/abc123';
    const buf = makeTorrent({ name: 'test.mkv', size: 1024 * 1024, webseedUrl: url });
    expect(extractWebseed(buf)).toBe(url);
  });

  it('works with size 0', () => {
    const url = 'http://example.com/stream/xyz';
    const buf = makeTorrent({ name: 'empty.mkv', size: 0, webseedUrl: url });
    expect(extractWebseed(buf)).toBe(url);
  });

  it('produces a Buffer', () => {
    const buf = makeTorrent({ name: 'f.mkv', size: 100, webseedUrl: 'http://x.com/s/y' });
    expect(Buffer.isBuffer(buf)).toBe(true);
    expect(buf.length).toBeGreaterThan(0);
  });

  it('encodes name into the torrent', () => {
    const buf = makeTorrent({ name: 'movie.mkv', size: 500, webseedUrl: 'http://x.com/s/z' });
    expect(buf.toString()).toContain('movie.mkv');
  });
});

describe('extractWebseed', () => {
  it('returns null for empty buffer', () => {
    expect(extractWebseed(Buffer.alloc(0))).toBeNull();
  });

  it('returns null for non-torrent data', () => {
    expect(extractWebseed(Buffer.from('not a torrent'))).toBeNull();
  });

  it('returns null when url-list is missing', () => {
    // Bencode a dict without url-list
    const buf = makeTorrent({ name: 'f.mkv', size: 0, webseedUrl: 'http://x.com/s/a' });
    // Corrupt the url-list key to make it missing
    const str = buf.toString('binary').replace('url-list', 'url-xxxx');
    const corrupted = Buffer.from(str, 'binary');
    expect(extractWebseed(corrupted)).toBeNull();
  });

  it('handles url-list as array', () => {
    // Manually build a torrent-like bencode with url-list as list
    const { makeTorrent: mt } = require('../src/torrent');
    // We test via the actual makeTorrent which uses a string — round-trip test above covers it.
    // Here just verify the array branch: if url-list is a Buffer (string) it still returns a string.
    const url = 'http://cdn.example.com/stream/abcdef';
    const buf = mt({ name: 't.mkv', size: 50, webseedUrl: url });
    expect(typeof extractWebseed(buf)).toBe('string');
  });
});