/**
 * Returns true if the given inspection expiry date string is within 1 month
 * from today (or already past).
 * @param {string} inspectionExpiry - ISO date string (YYYY-MM-DD) or empty
 * @returns {boolean}
 */
export function isInspectionExpirySoon(inspectionExpiry) {
  if (!inspectionExpiry) return false;
  const expiry = new Date(inspectionExpiry);
  const oneMonthLater = new Date();
  oneMonthLater.setMonth(oneMonthLater.getMonth() + 1);
  return expiry <= oneMonthLater;
}

/**
 * Formats a date range with optional AM/PM periods into a display string.
 * @param {string} startDate - ISO date string (YYYY-MM-DD)
 * @param {string} startPeriod - '午前', '午後', or ''
 * @param {string} endDate - ISO date string (YYYY-MM-DD)
 * @param {string} endPeriod - '午前', '午後', or ''
 * @returns {string}
 */
export function formatDateRange(startDate, startPeriod, endDate, endPeriod) {
  const start = startDate.slice(5) + (startPeriod ? ' ' + startPeriod : '');
  const end = endDate.slice(5) + (endPeriod ? ' ' + endPeriod : '');
  return `${start} 〜 ${end}`;
}

/**
 * Formats a reservation tooltip string with full dates and optional periods.
 * @param {object} r - reservation object
 * @returns {string}
 */
export function formatReservationTooltip(r) {
  const start = r.start_date + (r.start_period ? ' ' + r.start_period : '');
  const end = r.end_date + (r.end_period ? ' ' + r.end_period : '');
  return `${r.customer_name || '予約'}\n${start} 〜 ${end}${r.notes ? '\n' + r.notes : ''}`;
}