export const isValidExpDate = (expDate: string): boolean => { if (typeof expDate !== 'string' || expDate.length !== 5) return false; const [monthStr, yearStr] = expDate.split('/'); if (!monthStr || !yearStr) return false; const month = parseInt(monthStr, 10); const year = parseInt(yearStr, 10); if (isNaN(month) || isNaN(year) || month < 1 || month > 12) return false; const currentDate = new Date(); const currentYear = currentDate.getFullYear() % 100; const currentMonth = currentDate.getMonth() + 1; return year > currentYear || (year === currentYear && month >= currentMonth); };