Function parseCliArgs

src/cli.ts:181–313

(argv: string[])

};

const parseCliArgs = (argv: string[]): ParsedOptions | null => {
  if (argv.length === 0 || argv.includes('-h') || argv.includes('--help')) {
    return null;
  }

  let commandArg = argv[0];
  if (commandArg.startsWith('--')) {
    commandArg = commandArg.slice(2);
  }
  if (commandArg !== 'riff' && commandArg !== 'chord' && commandArg !== 'arp') {
    throw new TypeError(
      `First argument must be riff/chord/arp (or --riff/--chord/--arp), received "${argv[0]}"`
    );
  }

  const positionals: string[] = [];
  const options: ParsedOptions = {
    command: commandArg,
    positionals,
    outfile: 'music.mid',
    fitPattern: true,
  };

  let i = 1;
  while (i < argv.length) {
    const token = argv[i];
    if (!token.startsWith('--')) {
      positionals.push(token);
      i++;
      continue;
    }

    if (token === '--outfile') {
      options.outfile = argv[i + 1];
      i += 2;
      continue;
    }

    if (token === '--bpm') {
      options.bpm = Number(argv[i + 1]);
      i += 2;
      continue;
    }

    if (token === '--subdiv') {
      options.subdiv = argv[i + 1];
      i += 2;
      continue;
    }

    if (token === '--sizzle') {
      const styleOrNum = argv[i + 1];
      const maybeNum = argv[i + 2];
      if (!styleOrNum || styleOrNum.startsWith('--')) {
        options.sizzle = true;
        i += 1;
        continue;
      }