/**
 * DateDisplay
 * 
 * Deterministic date formatting for display.
 * Avoids Intl and toLocaleString to prevent SSR/hydration mismatches.
 */

export class DateDisplay {
  private static readonly MONTHS = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
  private static readonly FULL_MONTHS = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];
  private static readonly DAYS = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'];
  private static readonly FULL_DAYS = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'];

  /**
   * Formats a date as "MMM D, YYYY" (e.g., "Jan 1, 2024")
   */
  static formatShort(date: Date | string): string {
    const d = typeof date === 'string' ? new Date(date) : date;
    return `${this.MONTHS[d.getMonth()]} ${d.getDate()}, ${d.getFullYear()}`;
  }

  /**
   * Formats a date as "YYYY-MM-DD"
   */
  static formatIso(date: Date | string): string {
    const d = typeof date === 'string' ? new Date(date) : date;
    const month = (d.getMonth() + 1).toString().padStart(2, '0');
    const day = d.getDate().toString().padStart(2, '0');
    return `${d.getFullYear()}-${month}-${day}`;
  }

  /**
   * Formats a date as "Weekday, Month Day, Year"
   */
  static formatFull(date: Date | string): string {
    const d = typeof date === 'string' ? new Date(date) : date;
    return `${this.FULL_DAYS[d.getDay()]}, ${this.FULL_MONTHS[d.getMonth()]} ${d.getDate()}, ${d.getFullYear()}`;
  }

  /**
   * Formats a date as "MMM YYYY" (e.g., "Jan 2024")
   */
  static formatMonthYear(date: Date | string): string {
    const d = typeof date === 'string' ? new Date(date) : date;
    return `${this.MONTHS[d.getMonth()]} ${d.getFullYear()}`;
  }
}