import java.util.Scanner;

/**
 * CS 149 Exercise 5.4 Credit Card.
 *
 * @author
 * @version
 */
public class CreditCard {

    /**
     * Displays the given prompt, followed by ": ", and returns the next double
     * from the user. If the user input is not a double, this method discards
     * the next token and returns 0. It also consumes the newline character,
     * assuming that the input is the entire next line.
     *
     * @param in the Scanner to use
     * @param prompt the text to display
     * @return the user's input
     */
    public static double inputDouble(Scanner in, String prompt) {
    }

    /**
     * This method will take in the previous balance and additional charges and
     * compute the amount of interest. If the priorBalance is 0 or less, the
     * interest is 0. If there was a priorBalance, the interest is 2% of the
     * priorBalance plus the additional charges.
     *
     * @param priorBalance balance before new charges
     * @param addtlCharges charges added this month
     * @return amount of interest to charge
     */
    public static double calculateInterest(double priorBalance,
            double addtlCharges) {
    }

    /**
     * This method will take in the previous balance and additional charges and
     * compute the minimum payment.
     * <ul>
     * <li>$0.00 : for new balance less than $0</li>
     * <li>new balance : for new balance between $0 and $49.99 (inclusive)</li>
     * <li>$50.00 : for new balance between $50 and $300 (inclusive)</li>
     * <li>20% of the new balance : for new balance over $300</li>
     * </ul>
     *
     * @param balance after interest and charges are added
     * @return minimum payment amount
     */
    public static double calculateMinPayment(double balance) {
    }

    /**
     * Prompts the user for previous balance and additional charges; calculates
     * the interest, new balance, and minimum payment; displays the resulting
     * credit card statement.
     *
     * @param args command-line arguments
     */
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

        // make sure that the number entered is a double; if so, read it in;
        // if not, use a default value of zero; no error message to the user
        double priorBalance = inputDouble(in, "Type the previous balance");
        double addtlCharges = inputDouble(in, "Type the additional charges");

        // perform the calculation of interest, new balance, minimum payment
        double interest = calculateInterest(priorBalance, addtlCharges);
        double newBalance = priorBalance + addtlCharges + interest;
        double minPayment = calculateMinPayment(newBalance);

        // output the resulting credit card statement
        System.out.println("");
        System.out.println("CS CARD International Statement");
        System.out.println("===============================");
        System.out.printf("Previous balance:    $ %,8.2f\n", priorBalance);
        System.out.printf("Additional charges:  $ %,8.2f\n", addtlCharges);
        System.out.printf("Interest:            $ %,8.2f\n", interest);
        System.out.printf("New balance:         $ %,8.2f\n", newBalance);
        System.out.printf("Minimum payment:     $ %,8.2f\n", minPayment);
    }

}