rfid-database/src/lib/rfid/uid.ts

/**
 * Normalize RFID UIDs to uppercase hex without separators.
 * Accepts common forms: "04:A1:B2:C3", "04 A1 B2 C3", "04a1b2c3".
 */
export function normalizeUid(input: string): string {
  const cleaned = input.replace(/[^0-9a-fA-F]/g, "").toUpperCase();
  if (cleaned.length < 4 || cleaned.length % 2 !== 0) {
    throw new Error(
      `Invalid UID "${input}": expected even-length hex of at least 2 bytes`
    );
  }
  return cleaned;
}

/** Display form with colon separators: 04:A1:B2:C3 */
export function formatUid(uid: string): string {
  const normalized = normalizeUid(uid);
  return normalized.match(/.{1,2}/g)?.join(":") ?? normalized;
}

export function tryNormalizeUid(input: string): string | null {
  try {
    return normalizeUid(input);
  } catch {
    return null;
  }
}