import java.applet.*;
import java.io.*;
import java.util.*;
import java.awt.*;

public class cai extends Applet {

/*Declare Variables*/

	int process, MultiplicandDigits, MultiplierDigits, Multiplicand, Multiplier, num, answer, studentAnswer, problems, correct, totalProblems;
	Button Yes, No;
	TextField textAnswer;
	String temp, candString, plierString;
	boolean attempted, candUp;
	Random r;
	Date d;
	Font font;
	Graphics g;
	Color color;

	public void init() {

/*Initializes Variables*/

		process = 1;
		MultiplicandDigits = 1;
		MultiplierDigits = 1;
		Multiplicand = 1;
		Multiplier = 1;
		candUp = true;
		problems = 0;
		totalProblems = 0;
		correct = 0;	
	
/*Draws GUI*/

		setLayout(new BorderLayout());
			Panel p = new Panel();

/*Creates Panel for user interface*/

			p.setLayout(new FlowLayout());
			Yes = new Button("Yes");
			No = new Button("No");
			textAnswer = new TextField(15);
			p.add(Yes);
			p.add(new Label("          "));
			p.add(No);
			p.add(new Label("                     "));
			p.add(textAnswer);

/*Adds panel to GUI*/

			add("South", p);
	}

/*Handles clicks on buttons*/

	public boolean action(Event e, Object arg) {

/*If at first screen*/

		if ((e.target == Yes && process == 1) || (e.target == No && process == 1))  {

			problem();
			repaint();

		}

		else {		

/*If click on No when asking for answer*/

			if (e.target == No && process == 2) {

				textAnswer.setText("");

			}

			else {

/*If click on Yes when asking for answer*/

				if (e.target == Yes && process == 2) {

					check();
					repaint();

				}

				else {

/*If click on Yes on asking to continue*/

					if ((e.target == Yes) && (process == 3 || process == 5)) {

						score();
						problem();
						textAnswer.setText("");
						repaint();

					}

					else {

/*If click on Yes on asking to try problem again*/

						if ((e.target == Yes) && (process == 4)) {

							process = 2;
							repaint();

						}

						else {
			
/*If click on No on asking to try problem again or to continue*/

							if ((e.target == No) && (process == 3 || process == 4 || process == 5)) {
		
								process = 6;
								repaint();	

							}

						}

					}

				}

			}

		}

		return super.action(e, arg);

	}

/*Creates new problem*/

	public void problem() {

		Date d = new Date();
		r = new Random(d.getTime());
		attempted = false;
		problems++;
		totalProblems++;
		int num = r.nextInt () % ((MultiplicandDigits * 10) - 1);
		Multiplicand = (Math.abs(num) + 1);
		num = r.nextInt () % ((MultiplierDigits * 10) - 1);
		Multiplier = (Math.abs(num) + 1);
		numberCheck();
		process = 2;
		System.out.println("Process " + process);
		return;

	}

/*Checks number to make sure they are of correct digit length. If not, new random numbers are generated*/

	public void numberCheck() {

		System.out.println("Test for Multiplicand: " + Math.pow(10, (MultiplicandDigits - 1)));
		System.out.println("Test for Multiplier: " + Math.pow(10, (MultiplierDigits - 1)));

		while (Multiplicand < Math.pow(10, (MultiplicandDigits - 1))) {

			int num = r.nextInt () % ((MultiplicandDigits * 10) - 1);
			Multiplicand = (Math.abs(num) + 1);

		}

		while (Multiplier < Math.pow(10, (MultiplierDigits - 1))) {

			num = r.nextInt () % ((MultiplierDigits * 10) - 1);
			Multiplier = (Math.abs(num) + 1);

		}

	return;

	}

/*Compares answer that student gave to correct answer.*/

	public void check() {

		answer = Multiplicand * Multiplier;
		studentAnswer = intFromTextField(textAnswer);

/*If answer is correct*/

		if (answer == studentAnswer) {

			process = 3;
			System.out.println("process " + process);
			correct++;
			
		}

		else {

/*If answer isn't correct and it hasn't been attempted yet.*/

			if (answer != studentAnswer && attempted == false) {
		
				attempted = true;
				process = 4;
				System.out.println("process " + process);

			}
	
			else {

/*If answer is wrong and problem has been attempted before.*/

				if (answer != studentAnswer && attempted == true) {

					process = 5;
					System.out.println("process " + process);

				}

			}

		}


		return;
	
	}
		
/*Calculates score to see if difficulty should be raised.*/

	public void score() {

		if ((problems > 5) && ((correct * 100) / (problems) > 89)) {

			if (candUp == true) {

				problems = 0;
				candUp = false;
				MultiplicandDigits++;

			}

			else {

				problems = 0;
				candUp = true;
				MultiplierDigits++;

			}

		}

		return;

	}	

/*Draws on GUI*/

	public void paint(Graphics g) {

/*Original screen*/

		if (process == 1) {

			g.setColor(Color.black);
			g.setFont(new Font ("Helvetica", Font.BOLD, 20));
			g.drawString("Welcome to the tester!", 80, 100);
			g.setFont(new Font ("Helvetica", Font.PLAIN, 12));
			g.drawString("Press a button to start.", 35, 275);

		}
		
/*Asking question*/

		if (process == 2) {
			
			g.setColor(Color.black);
			g.setFont(new Font ("Helvectica", Font.BOLD, 12));
			candString = intToString(Multiplicand);
			System.out.println(candString);
			g.drawString(candString, (350 - (MultiplicandDigits * 7)), 250);
			plierString = intToString(Multiplier);
			System.out.println(plierString);
			g.drawString(plierString, (350 - (MultiplierDigits * 7)), 275);
			g.drawString("X", (350 - ((MultiplierDigits + 2) * 7)), 275);
			g.setFont(new Font ("Helvecitca", Font.BOLD, 20));
			g.drawString("Now try this one!", 100, 100);
			g.setFont(new Font ("Helvecitca", Font.PLAIN, 12));
			g.drawString("Is this the answer?", 40, 275);

		}

/*You are correct screen*/

		if (process == 3) {

			g.setColor(Color.red);
			g.setFont(new Font ("Helvectica", Font.BOLD, 24));
			g.drawString("You are", 150, 100);
			g.drawString("correct!", 150, 150);
			g.setColor(Color.black);
			g.setFont(new Font ("Helvecitca", Font.PLAIN, 12));
			g.drawString("Press yes to continue or no to stop.", 35, 275);
			g.drawString(plierString, (350 - (MultiplierDigits * 7)), 275);
			g.drawString(candString, (350 - (MultiplicandDigits * 7)), 250);
			g.drawString("X", (350 - ((MultiplierDigits + 2) * 7)), 275);

		}

/*You are wrong screen*/

		if (process == 4) {
		
			g.setColor(Color.black);
			g.setFont(new Font ("Helvectica", Font.BOLD, 24));
			g.drawString("Sorry...", 100, 100);
			g.drawString("Your answer is wrong.", 50, 150);
			g.setFont(new Font ("Helvecitca", Font.PLAIN, 12));
			g.drawString("Press yes to try again, no to stop.", 35, 275);
			g.drawString(plierString, (350 - (MultiplierDigits * 7)), 275);
			g.drawString(candString, (350 - (MultiplicandDigits * 7)), 250);
			g.drawString("X", (350 - ((MultiplierDigits + 2) * 7)), 275);

		}

/*Correct answer screen*/

		if (process == 5) {
	
			g.setColor(Color.black);
			g.setFont(new Font ("Helvectica", Font.BOLD, 24));
			g.drawString("Sorry...", 100, 100);
			g.drawString("Your answer is wrong.", 50, 150);
			temp = intToString(answer);
			g.drawString("The correct answer is " + temp, 50, 200);
			g.setFont(new Font ("Helvecitca", Font.PLAIN, 12));
			g.drawString("Press yes to continue, no to stop.", 35, 275);
			g.drawString(plierString, (350 - (MultiplierDigits * 7)), 275);
			g.drawString(candString, (350 - (MultiplicandDigits * 7)), 250);
			g.drawString("X", (350 - ((MultiplierDigits + 2) * 7)), 275);

		}

/*Goodbye screen*/

		if (process == 6) {
		
			g.setColor(Color.red);
			g.setFont(new Font ("Helvecitca", Font.BOLD, 24));
			g.drawString("Goodbye!", 100, 100);
			temp = intToString(totalProblems);
			g.drawString("You tried " + temp + " problems.", 100, 150);
			temp = intToString(correct);
			g.drawString("You got " + temp + " correct.", 100, 200);

		}

	}

/*Converts intergers to strings*/

	String intToString(int i) {
		String tmp = "";
		return tmp.valueOf(i);
	
	}

/*Converts strings to intergers*/

	int intFromTextField(TextField tf) {
		String TextforConversion;
		int IntegerReturned;
			TextforConversion = tf.getText();
				try {
					IntegerReturned = Integer.parseInt(TextforConversion);
				}
				catch (Exception e) {
					IntegerReturned = 0;
				}
		return IntegerReturned;
	}

}