/**
 * Title:        Chapter 3, "Control Statements"
 * Description:  Chapter 3 Examples
 * Copyright:    Copyright (c) 2000
 * Company:      Armstrong Atlantic State University
 * @author Y. Daniel Liang
 * @version 1.0
 */

// TestIfElse.java: Test if-else statements

public class TestIfElse
{
  /**Main method*/
  public static void main(String[] args)
  {
    double annualInterestRate = 0;
    int numOfYears;
    double loanAmount;

    // Enter number of years
    System.out.print(
      "Enter number of years (7, 15 and 30 only): ");
    numOfYears = MyInput.readInt();

    // Find interest rate based on year
    if (numOfYears == 7)
      annualInterestRate = 7.25;
    else if (numOfYears == 15)
      annualInterestRate = 8.50;
    else if (numOfYears == 30)
      annualInterestRate = 9.0;
    else
    {
      System.out.println("Wrong number of years");
      System.exit(0);
    }

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

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

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

    // Display results
    System.out.println("The monthly payment is " +
      (int)(monthlyPayment*100)/100.0);
    System.out.println("The total payment is " +
      (int)(totalPayment*100)/100.0);
  }
}

// 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() + "'");
    }
}