export function normalizeFa(input: string) {
  return input
    .replace(/[\u200c\u0640]/g, '')
    .replace(/[\u064b-\u0652]/g, '')
    .replace(/[يى]/g, 'ی')
    .replace(/ك/g, 'ک')
    .replace(/[أإآٱ]/g, 'ا')
    .replace(/\s+/g, ' ')
    .trim()
    .toLowerCase();
}

export function computeStreak(streakCount: number, lastReadAt: Date | null, now: Date): number {
  if (!lastReadAt) return 1;
  const lastDate = new Date(lastReadAt);
  lastDate.setHours(0, 0, 0, 0);
  const today = new Date(now);
  today.setHours(0, 0, 0, 0);
  const diffDays = Math.floor((today.getTime() - lastDate.getTime()) / (1000 * 60 * 60 * 24));
  if (diffDays === 1) return streakCount + 1;
  if (diffDays > 1) return 1;
  return streakCount;
}

export function currentStreakIfAlive(streakCount: number, lastReadAt: Date | null, now: Date): number {
  if (!lastReadAt) return 0;
  const lastDate = new Date(lastReadAt);
  lastDate.setHours(0, 0, 0, 0);
  const today = new Date(now);
  today.setHours(0, 0, 0, 0);
  const diffDays = Math.floor((today.getTime() - lastDate.getTime()) / (1000 * 60 * 60 * 24));
  if (diffDays > 1) return 0;
  return streakCount;
}