/* Title      - Credit Card Type
 * File name  - Lab18
 * Programmer - 415 Erich Musick
 * IPO        - Input   - User inputs a credit card number
 *              Process - The program determines, based on the first few numbers
 *                of the credit card, what type of credit card the number
 *                identifies
 *              Output  - The type of credit card is displayed
*/

/*************************** H E A D E R  F I L E S ***************************/
//#include "iostream.h"
#include "waittoclose.h"      // Add to project waittoclose.cpp
//#include "apstring.h"       // Add to project apstring.cpp
//#include "randgen.h"        // Add to project randgen.cpp
#pragma hdrstop
#include "apvector.h"       // DO NOT ADD TO PROJECT apvector.cpp
//#include "apmatrix.h"       // DO NOT ADD TO PROJECT apmatrix.cpp

/******************** F U N C T I O N  P R O T O T Y P E S ********************/
char CreditCardType(apvector cardNumber);

/****************************** F U N C T I O N S *****************************/
// CREDIT CARD TYPE
 /* purpose    - Determine the type of credit card using the account number
  * parameters - cardNumber - apvector of chars containing user's account
  *               (credit card) number
  * input      - None.
  * process    - The program uses a switch statement to determine the card type,
  *               based on the first few numbers of the account number
  * output     - None.
  * return     - cardType - char containing a letter representing the card type
  *               Possible values - V (if account is a Visa account)
  *                               - M (if account is a Mastercard account)
  *                               - A (if account is an American Express acct)
  *                               - D (if account is a Discover account)
  *                               - X (if account is none of the above)
  */
char CreditCardType(apvector cardNumber) {
  char cardType;
  int index;

  switch (cardNumber[0]) {
    case '4':               // If first number is 4, card type is Visa
      cardType = 'V';
      break;

    case '5':               // If first number is 5, card type is Mastercard
      cardType = 'M';
      break;

    case '3':               // If first number is 3, test second number
      switch (cardNumber[1]) {
        case '7':           // If second number is 7, card is American Express
          cardType = 'A';
          break;

        default:
          cardType = 'X';   // Default card type is Unknown
          break;
      }
      break;

    case '6':               // If first number is 6, test second number
      switch (cardNumber[1]) {
        case '0':           // If second number is 0, test third number
          switch (cardNumber[2]) {
            case '1':       // If third number is 1, test fourth number
              switch (cardNumber[3]) {
                case '1':   // If fourth number is 1, card type is Discover
                  cardType = 'D';
                  break;

                default:    // Default card type is Unknown
                  cardType = 'X';
                  break;
              }
              break;

            default:        // Default card type is Unknown
              cardType = 'X';
              break;
          }
          break;

        default:            // Default card type is Unknown
          cardType = 'X';
          break;
      }
      break;

    default:               // Default card type is Unknown
      cardType = 'X';
      break;
  }

  return cardType;
}

int main() {
  char goAgain;                   // Contains user input (calculate another?)
  apvector cardNumber(16);  // Contains credit card number
  char cardType;                  // Contains card type
  int index;                      // vector index

  cout << "CREDIT CARD TYPE";
  cout << endl;
  cout << "Given a credit card number, this program determines type of ";
  cout << " credit card. The";
  cout << endl;
  cout << "program only recognizes American Express, Discover, Mastercard, and";
  cout << " Visa cards.";
  cout << endl;
  cout << endl;

  do {
    // USER INPUT: get credit card number
    cout << "                                   ";
    cout << "1234567890123456";
    cout << endl;
    cout << "Enter 16-digit credit card number: ";
    for (index=0; index < 16; index++) {
      cin >> cardNumber[index];
    }
    cin.ignore(80,'\n');

    // PROCESS: determine credit card type
    cardType = CreditCardType(cardNumber);

    // DISPLAY: display card number and type
    cout << endl;

    cout << "Card Number:";
    for (index=0; index < 16; index++) {
      if ((index % 4) == 0) {     // Display a space after every four digits
        cout << " ";
      }
      cout << cardNumber[index];
    }
    cout << endl;

    cout << "Card Type: ";
    switch (cardType) {
      case 'A':
        cout << "American Express";
        break;

      case 'D':
        cout << "Discover";
        break;

      case 'M':
        cout << "Mastercard";
        break;

      case 'V':
        cout << "Visa";
        break;

      default:
        cout << "Unknown";
        break;
    }
    cout << endl;
    cout << endl;

    // USER INPUT: Loop through again?
    cout << "Again (y/n)? ";
    cin >> goAgain;
    cin.ignore(80,'\n');

    // DISPLAY: Leave an extra space if user would like to loop through again.
    if (goAgain == 'y' || goAgain == 'Y') {
      cout << endl;
    }
  } while (goAgain == 'y' || goAgain == 'Y');

  return 0;
}

/************************** S A M P L E  O U T P U T **************************/
/*               LAB18 by 415 ERICH MUSICK   10:52 on Dec  4 2001

CREDIT CARD TYPE
Given a credit card number, this program determines type of  credit card. The
program only recognizes American Express, Discover, Mastercard, and Visa cards.

                                   1234567890123456
Enter 16-digit credit card number: 3756432165865435

Card Number: 3756 4321 6586 5435
Card Type: American Express

Again (y/n)? y

                                   1234567890123456
Enter 16-digit credit card number: 3856432154846543

Card Number: 3856 4321 5484 6543
Card Type: Unknown

Again (y/n)? y

                                   1234567890123456
Enter 16-digit credit card number: 4658465132165445

Card Number: 4658 4651 3216 5445
Card Type: Visa

Again (y/n)? y

                                   1234567890123456
Enter 16-digit credit card number: 5654846513213465

Card Number: 5654 8465 1321 3465
Card Type: Mastercard

Again (y/n)? y

                                   1234567890123456
Enter 16-digit credit card number: 6011548946513214

Card Number: 6011 5489 4651 3214
Card Type: Discover

Again (y/n)? n

'Esc' closes window.*/

/*               LAB18 by 415 ERICH MUSICK   10:52 on Dec  4 2001

CREDIT CARD TYPE
Given a credit card number, this program determines type of  credit card. The
program only recognizes American Express, Discover, Mastercard, and Visa cards.

                                   1234567890123456
Enter 16-digit credit card number: 6012987654321564

Card Number: 6012 9876 5432 1564
Card Type: Unknown

Again (y/n)? y

                                   1234567890123456
Enter 16-digit credit card number: 6022654846513214

Card Number: 6022 6548 4651 3214
Card Type: Unknown

Again (y/n)? y

                                   1234567890123456
Enter 16-digit credit card number: 6222548465465432

Card Number: 6222 5484 6546 5432
Card Type: Unknown

Again (y/n)? y

                                   1234567890123456
Enter 16-digit credit card number: 9654231654845234

Card Number: 9654 2316 5484 5234
Card Type: Unknown

Again (y/n)? y

                                   1234567890123456
Enter 16-digit credit card number: 2368548465132123

Card Number: 2368 5484 6513 2123
Card Type: Unknown

Again (y/n)? n

'Esc' closes window.*/