/* 
 * This file is part of the Echo Web Application Framework (hereinafter "Echo").
 * Copyright (C) 2002 NextApp, Inc.
 *
 * Echo is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Echo is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Echo; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

import nextapp.echo.Button;
import nextapp.echo.Color;
import nextapp.echo.ContentPane;
import nextapp.echo.EchoInstance;
import nextapp.echo.Filler;
import nextapp.echo.Font;
import nextapp.echo.HttpImageReference;
import nextapp.echo.Label;
import nextapp.echo.TextField;
import nextapp.echo.Window;

import nextapp.echo.event.ActionListener;
import nextapp.echo.event.ActionEvent;

import nextapp.echoservlet.EchoServer;

public class NumberGuessServlet extends EchoServer {

    public EchoInstance newInstance() {
        return new NumberGuess();
    }
}

class NumberGuess extends EchoInstance {
    
    private Window window;
    
    public Window init() {
       window = new Window("Number Guessing Game");
       startNewGame();
       
       return window;
    }
       
    public void startNewGame() {
        // Set the content to be a new GamePane, so the 
        window.setContent(new GamePane(this));
    }
    
    public void congratulate(int numberOfTries) {
        window.setContent(new CongratulationsPane(this, 
                numberOfTries));
    }
}

// The GamePane class extends ContentPane.  The
// startNewGame() method in the NumberGuess class sets the 
// content of the browser's window to be a new GamePane. 
// The GamePane's instance variables contain information 
// about the state of the game, such as what the random 
// number is and how many guesses have been made.
class GamePane extends ContentPane 
implements ActionListener {

    private NumberGuess numberGuess;
    private int randomNumber 
            = ((int) Math.floor(Math.random() * 100)) + 1;
    private int lowerBound = 1;
    private int upperBound = 100;
    private int numberOfTries = 0;
    private TextField guessEntryField;
    private Label statusLabel = new Label();
    private Label countLabel 
            = new Label("You have made no guesses.");
    private Label promptLabel= new Label("Guess a number "
            + "between 1 and 100: ");
    private int guess;
    
    public GamePane(NumberGuess numberGuess) {
        super();
        
        this.numberGuess = numberGuess;
        
        // An example of a label that contains an image.  
        Label titleLabel = new Label(new HttpImageReference(
                "images/guess_a_number.png"));
        add(titleLabel);

        // Adding a vertical strut will cause a 10 pixel 
        // vertical margin to appear between the titleLabel 
        // added above and the statusLabel added below it.
        add(Filler.createVerticalStrut(10));

        add(statusLabel);
        
        add(Filler.createVerticalStrut(10));

        add(countLabel);

        add(Filler.createVerticalStrut(10));

        add(promptLabel);
        
        // Creates a new empty text field
        // that displays 3 characters of data.
        guessEntryField = new TextField(3);
        
        guessEntryField.setForeground(Color.WHITE);
        guessEntryField.setBackground(Color.BLUE);
        add(guessEntryField);
        
        add(Filler.createVerticalStrut(10));
        
        Button submitButton 
                = new Button("Submit Your Guess");
        submitButton.setActionCommand("submit guess");
        submitButton.setForeground(Color.BLACK);
        submitButton.setBackground(Color.GREEN);
        submitButton.addActionListener(this);
        add(submitButton);
        
        add(Filler.createVerticalStrut(10));

        Button newGameButton 
                = new Button("Start a New Game");
        newGameButton.setActionCommand("new game");
        newGameButton.setForeground(Color.WHITE);
        newGameButton.setBackground(Color.RED);
        newGameButton.addActionListener(this);
        add(newGameButton);
    }
    
    public void actionPerformed(ActionEvent e) {
        if (e.getActionCommand().equals("new game")) {
            numberGuess.startNewGame();
        } else if (e.getActionCommand()
                .equals("submit guess")) {
            ++numberOfTries;
            
            if (numberOfTries == 1) {
                countLabel.setText("You have made 1 guess.");
            } else {
                countLabel.setText("You have made " 
                        + numberOfTries + " guesses.");
            }

            try {
                guess = Integer.parseInt(
                        guessEntryField.getText());
            } catch (NumberFormatException ex) {
                statusLabel.setText(
                        "Your guess was not valid.");
                return;
            }

            if (guess == randomNumber) {
                numberGuess.congratulate(numberOfTries);
            } else if (guess < 1 || guess > 100) {
                statusLabel.setText("Your guess, " + guess 
                        + " was not between 1 and 100.");
            } else if (guess < randomNumber) {
                if (guess >= lowerBound) {
                    lowerBound = guess + 1;
                }
                statusLabel.setText("Your guess, " + guess
                        + " was too low.  Try again:");
            } else if (guess > randomNumber) {
                statusLabel.setText("Your guess, " + guess
                        + " was too high.  Try again:");
                if (guess <= upperBound) {
                    upperBound = guess - 1;
                }
            }
            
            promptLabel.setText("Guess a number between "
                    + lowerBound + " and " 
                    + upperBound + ": ");
        }
    }
}

// Like the GamePane class, the CongratulationsPane extends
// ContentPane.  The game will replace the GamePane being
// held in its window with a CongratulationsPane when the
// user guesses the number correctly, by calling the 
// congratulate() method in the NumberGuess class.
class CongratulationsPane extends ContentPane
implements ActionListener {

    private NumberGuess numberGuess;

    public CongratulationsPane(NumberGuess numberGuess, 
            int numberOfTries) {
        this.numberGuess = numberGuess;
        
        Label label = new Label(new HttpImageReference(
                "images/congratulations.png"));
        add(label);
        
        add(Filler.createVerticalStrut(20));

        add(new Label("You got the correct answer in " 
                + numberOfTries 
                + (numberOfTries == 1 ? 
                " try." : " tries.")));

        add(Filler.createVerticalStrut(40));
        
        Button button = new Button("Play Again");
        button.addActionListener(this);
        add(button);
    }

    public void actionPerformed(ActionEvent e) {
        numberGuess.startNewGame();
    }
}