/** 工号规则：IDE + 至少 3 位数字，如 IDE001、IDE012、IDE1000 */
const EMPLOYEE_NO_PATTERN = /^IDE(\d{3,})$/i

export function generateEmployeeNo(
  existing: Array<{ employeeNo?: string | null; EmployeeNo?: string | null }>,
): string {
  let max = 0
  for (const row of existing) {
    const raw = String(row.employeeNo ?? row.EmployeeNo ?? '').trim()
    const match = raw.match(EMPLOYEE_NO_PATTERN)
    if (match) {
      max = Math.max(max, Number.parseInt(match[1], 10))
    }
  }
  const next = max + 1
  return `IDE${String(next).padStart(3, '0')}`
}