export const isValidPhone = (value: string) => /^[0-9]{10}$/.test(value.replace(/\D/g, ''));

export const isValidOtp = (value: string) => /^[0-9]{6}$/.test(value);

/**
 * Single source of truth for how many digits an MPIN has. The backend accepts
 * 4 or 6; this app standardises on 4, so the keypad, the validators and the
 * stored-profile handling all read from here rather than each hard-coding it.
 */
export const MPIN_LENGTH = 4;

/**
 * The backend refuses an all-same-digit MPIN. That rule is checked after
 * decryption server-side, so it comes back as a `VALIDATION_ERROR` with a
 * message rather than a field map — cheaper and clearer to catch it here
 * before spending a round trip.
 */
export const isValidMpin = (value: string) =>
  new RegExp(`^[0-9]{${MPIN_LENGTH}}$`).test(value) && !isRepeatedDigits(value);

export const isRepeatedDigits = (value: string) =>
  value.length > 0 && /^(\d)\1*$/.test(value);

/** Constraints as the API documents them, not as any one bank formats them. */
export const isValidAccountNumber = (value: string) => /^[0-9]{5,20}$/.test(value);

export const isValidIfsc = (value: string) => /^[A-Za-z0-9]{6,15}$/.test(value);

export const isValidMmid = (value: string) => /^[0-9]{7}$/.test(value);

export const isValidNickname = (value: string) => value.length <= 60;

export const isValidAmount = (value: string) => {
  const amount = Number(value);
  return Number.isFinite(amount) && amount > 0;
};