/**
 * Title:        Chapter 2, "Primitive Data Types and Operations"
 * Description:  Examples for Chapter 2
 * Copyright:    Copyright (c) 2000
 * Company:      Armstrong Atlantic State University
 * @author Y. Daniel Liang
 * @version 1.0
 */

// ComputeMortgage.java: Compute mortgage payments

public class ComputeMortgage
{
  /**Main method*/
  public static void main(String[] args)
  {
    double annualInterestRate;
    int numOfYears;
    double loanAmount;

    // Enter yearly interest rate
    System.out.print(
      "Enter yearly interest rate, for example 8.25: ");
    annualInterestRate = MyInput.readDouble();

    // Obtain monthly interest rate
    double monthlyInterestRate = annualInterestRate/1200;

    // Enter number of years
    System.out.print(
      "Enter number of years as an integer, for example 5: ");
    numOfYears = MyInput.readInt();

    // Enter loan amount
    System.out.print("Enter loan amount, for example 120000.95: ");
    loanAmount = MyInput.readDouble();

    // Calculate payment
    double monthlyPayment = loanAmount*monthlyInterestRate/
      (1 - 1/(Math.pow(1 + monthlyInterestRate, numOfYears*12)));
    double totalPayment = monthlyPayment*numOfYears*12;

    // Display results
    System.out.println("The monthly payment is " + monthlyPayment);
    System.out.println("The total payment is " + totalPayment);
  }
}

//-----------

// a class for reading various types from the keyboard (System.in) 
class MyInput
{
    public static String readString()
    {
        String string = "";
        java.io.BufferedReader bufferedReader = 
           new java.io.BufferedReader(new java.io.InputStreamReader(System.in));
        try
        {
            string = bufferedReader.readLine();
        }
        catch (java.io.IOException ex)
        {
            throw new RuntimeException(ex);
        }
        return string;
    }

    public static int readInt()
    {
        return Integer.parseInt(readString());
    }

    public static double readDouble()
    {
        return Double.parseDouble(readString());
    }

    // test all the methods of this class
    public static void main(String[] args)
    {
        System.out.println("Testing 'readString()'");
        System.out.print("Input your string : ");
        System.out.println("Your string was '" + readString() + "'");
        System.out.println("\nTesting 'readInt()'");
        System.out.print("Input your int : ");
        System.out.println("Your int was '" + readInt() + "'");
        System.out.println("\nTesting 'readDouble()'");
        System.out.print("Input your double : ");
        System.out.println("Your double was '" + readDouble() + "'");
    }
}