/** The newest Android release, as the server reports it (GET /app/android/latest). */
export interface AppUpdateDTO {
  /** e.g. "1.2.0" (the release tag without its "v"). */
  version: string;
  /** Where to download the APK (through our server, so the release host can stay private). */
  apkUrl: string;
  /** Hex SHA-256 of the APK; the phone checks it before installing. */
  sha256: string;
  size: number;
  /** What's new, from the release notes. */
  notes: string | null;
  publishedAt: string;
}

/** "1.10.0" → [1, 10, 0]; null for anything that isn't a plain dotted version (an optional leading "v" is fine). */
export function parseVersion(version: string): number[] | null {
  const m = /^v?(\d+(?:\.\d+)*)$/.exec(version.trim());
  return m ? m[1]!.split('.').map(Number) : null;
}

/** True when `candidate` is a later version than `current`. Unparseable versions are never newer. */
export function isNewerVersion(candidate: string, current: string): boolean {
  const a = parseVersion(candidate);
  const b = parseVersion(current);
  if (!a || !b) return false;
  for (let i = 0; i < Math.max(a.length, b.length); i++) {
    const diff = (a[i] ?? 0) - (b[i] ?? 0);
    if (diff !== 0) return diff > 0;
  }
  return false;
}