import java.util.Scanner;

/**
   This program demonstrates the use of mock objects
   for testing.
*/
public class GradingProgram
{
   public static void main(String[] args)
   {
      IGradeBook gradeBook = new MockGradeBook();
      Scanner in = new Scanner(System.in);
      boolean done = false;
      while (!done) 
      {
         System.out.print("L)oad A)dd aV)erage S)ave Q)uit: ");
         String command = in.next().toUpperCase();
         if (command.equals("L")) 
         {
            System.out.print("Filename: ");
            String filename = in.next();
            gradeBook.load(filename);
         }
         else if (command.equals("S")) 
         {
            System.out.print("Filename: ");
            String filename = in.next();
            gradeBook.save(filename);
         }
         else if (command.equals("A")) 
         {
            System.out.print("ID: ");
            int id = in.nextInt();
            System.out.print("Score: ");
            double score = in.nextDouble();
            gradeBook.addScore(id, score);
         }
         else if (command.equals("V")) 
         {
            System.out.print("ID: ");
            int id = in.nextInt();
            System.out.println("Average for " + id + ": " 
               + gradeBook.getAverageScore(id));
         }
         else if (command.equals("Q")) 
         {
            done = true;
         }         
      }
   }
}