import { format, isToday, isTomorrow, formatDistance } from 'date-fns';
import { fr } from 'date-fns/locale';

/**
 * Format a date as a short date string (e.g., "15 jun.")
 */
export function formatShortDate(date: Date | string): string {
  const dateObj = date instanceof Date ? date : new Date(date);
  return format(dateObj, 'd MMM', { locale: fr });
}

/**
 * Format a time as a 24-hour time string (e.g., "14:30")
 */
export function formatTime(date: Date | string): string {
  const dateObj = date instanceof Date ? date : new Date(date);
  return format(dateObj, 'HH:mm', { locale: fr });
}

/**
 * Format a date as a relative string (e.g., "Today", "Tomorrow", "Monday")
 */
export function formatRelativeDate(date: Date | string, includeTime: boolean = false): string {
  const dateObj = date instanceof Date ? date : new Date(date);
  
  let dateString = "";
  
  if (isToday(dateObj)) {
    dateString = "Today";
  } else if (isTomorrow(dateObj)) {
    dateString = "Tomorrow";
  } else {
    dateString = format(dateObj, 'EEEE d MMMM', { locale: fr });
  }
  
  if (includeTime) {
    dateString += ` · ${format(dateObj, 'HH:mm', { locale: fr })}`;
  }
  
  return dateString;
}

/**
 * Format a date as a relative time ago (e.g., "5 minutes ago", "2 hours ago")
 */
export function formatTimeAgo(date: Date | string): string {
  const dateObj = date instanceof Date ? date : new Date(date);
  return formatDistance(dateObj, new Date(), {
    addSuffix: true,
    locale: fr,
  });
}

/**
 * Format a date for display in isoformat
 */
export function formatISODate(date: Date | string): string {
  const dateObj = date instanceof Date ? date : new Date(date);
  return dateObj.toISOString();
}

/**
 * Check if a date string is valid
 */
export function isValidDateString(dateStr: string): boolean {
  if (!dateStr || dateStr === '0000-00-00 00:00:00') return false;
  
  try {
    const date = new Date(dateStr);
    return !isNaN(date.getTime());
  } catch (e) {
    return false;
  }
}

/**
 * Get a formatted month name
 */
export function getMonthName(month: number, short: boolean = false): string {
  const date = new Date();
  date.setMonth(month);
  return format(date, short ? 'MMM' : 'MMMM', { locale: fr });
}

/**
 * Get a formatted day name
 */
export function getDayName(day: number, short: boolean = false): string {
  const date = new Date();
  date.setDate(day);
  return format(date, short ? 'EEE' : 'EEEE', { locale: fr });
}