import mpMastercard from '../assets/img/mp_mastercard.png';
import mpVisa from '../assets/img/mp_visa.png';
import mpAmex from '../assets/img/mp_amex.jpg';
import mpTroy from '../assets/img/mp_troy.png';
import mpOther from '../assets/img/mp_other.png';

export const formatCardNumber = (value: string): string => {
  const cleanValue = value.replace(/\D/g, '');

  const formatted = cleanValue.replace(/(\d{4})(?=\d)/g, '$1 ');

  return formatted.substring(0, 23);
};

export const formatExpiryDate = (value: string): string => {
  const cleanValue = value.replace(/\D/g, '');

  if (cleanValue.length >= 2) {
    return `${cleanValue.substring(0, 2)}/${cleanValue.substring(2, 4)}`;
  }

  return cleanValue;
};

export const formatCVV = (value: string): string => {
  return value.replace(/\D/g, '').substring(0, 4);
};

export const detectCardType = (cardNumber: string): string => {
  const cleanNumber = cardNumber.replace(/\D/g, '');

  if (/^4/.test(cleanNumber)) {
    return 'visa';
  }

  if (/^5[1-5]/.test(cleanNumber) || /^2[2-7]/.test(cleanNumber)) {
    return 'mastercard';
  }

  if (/^3[47]/.test(cleanNumber)) {
    return 'amex';
  }

  if (/^6(?:011|5)/.test(cleanNumber)) {
    return 'discover';
  }

  if (/^9792/.test(cleanNumber)) {
    return 'troy';
  }

  return 'unknown';
};

export const getCvcLength = (cardType: string): number => {
  return cardType === 'amex' ? 4 : 3;
};

export const maskCardNumber = (cardNumber: string): string => {
  const cleanNumber = cardNumber.replace(/\D/g, '');
  if (cleanNumber.length < 4) return cardNumber;

  const lastFour = cleanNumber.slice(-4);
  const masked = '*'.repeat(cleanNumber.length - 4);

  return `${masked}${lastFour}`.replace(/(.{4})/g, '$1 ').trim();
};

export const validateCardNumber = (cardNumber: string): boolean => {
  const cleanNumber = cardNumber.replace(/\D/g, '');

  if (cleanNumber.length < 13 || cleanNumber.length > 19) {
    return false;
  }

  let sum = 0;
  let isEven = false;

  for (let i = cleanNumber.length - 1; i >= 0; i--) {
    let digit = parseInt(cleanNumber.charAt(i), 10);

    if (isEven) {
      digit *= 2;
      if (digit > 9) {
        digit -= 9;
      }
    }

    sum += digit;
    isEven = !isEven;
  }

  return sum % 10 === 0;
};

export const getCardBIN = (cardNumber: string): string => {
  const cleanNumber = cardNumber.replace(/\D/g, '');
  return cleanNumber.substring(0, 6);
};

export const getCardIcon = (cardBin: string) => {
  if (cardBin.startsWith('34') || cardBin.startsWith('37')) {
    return mpAmex;
  }

  if (cardBin.startsWith('9792')) {
    return mpTroy;
  }

  const bin2 = parseInt(cardBin.slice(0, 2));
  const bin4 = parseInt(cardBin.slice(0, 4));
  if ((bin2 >= 51 && bin2 <= 55) || (bin4 >= 2221 && bin4 <= 2720)) {
    return mpMastercard;
  }

  if (cardBin.startsWith('4')) {
    return mpVisa;
  }

  return mpOther;
};