wicket-examples/src/java/wicket/examples/hangman/Hangman.java

/*
 * $Id$ $Revision$
 * $Date$
 * 
 * ==================================================================== Licensed
 * under the Apache License, Version 2.0 (the "License"); you may not use this
 * file except in compliance with the License. You may obtain a copy of the
 * License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package wicket.examples.hangman;

import java.io.Serializable;

/**
 * Implementation of the actual hangman game model. The model holds the word
 * generator, the current word, retries remaining and the letters that have been
 * guessed. It also answers questions such as whether all retries have been
 * used.
 * 
 * @author Chris Turner
 * @author Jonathan Locke
 */
public class Hangman implements Serializable
{
	/** Serial version UID */
	private static final long serialVersionUID = 1L;
	private WordGenerator wordGenerator;
	private String currentWord;
	private char[] letters;
	private boolean[] guessedLetters;
	private int guessesRemaining;
	private int guessesAllowed;

	/**
	 * Initialise the hangman read for a new game.
	 * 
	 * @param guessesAllowed
	 *            Number of guesses allowed
	 * 
	 * @param word
	 *            The word to use or null to pick randomly
	 */
	public void newGame(final int guessesAllowed, final String word)
	{
		if (word != null)
		{
			wordGenerator = new WordGenerator(new String[] { word });
		}
		else
		{
			wordGenerator = new WordGenerator();
		}

		currentWord = wordGenerator.nextWord().toLowerCase();
		letters = new char[currentWord.length()];
		for (int i = 0; i < letters.length; i++)
			letters[i] = '_';
		guessedLetters = new boolean[26];
		for (int i = 0; i < guessedLetters.length; i++)
			guessedLetters[i] = false;
		this.guessesAllowed = guessesAllowed;
		guessesRemaining = guessesAllowed;
	}
	
	/**
	 * Play again with same settings
	 */
	public void newGame()
	{
		newGame(guessesAllowed, null);
	}

	/**
	 * Guess the given letter for the current word. If the letter matches then
	 * the word is updated otherwise the guesses remaining counter is reduced.
	 * The letter guessed is also recorded.
	 * 
	 * @param letter
	 *            The letter being guessed
	 * @return Whether the letter was in the word or not
	 */
	public boolean guessLetter(char letter)
	{
		letter = Character.toLowerCase(letter);
		boolean correctGuess = false;
		for (int i = 0; i < currentWord.length(); i++)
		{
			if (currentWord.charAt(i) == letter)
			{
				correctGuess = true;
				letters[i] = letter;
			}
		}
		if (!correctGuess && guessedLetters[letter - 'a'] == false)
			guessesRemaining--;
		guessedLetters[letter - 'a'] = true;
		return correctGuess;
	}

	/**
	 * Check whether the user has successfully guessed all of the letters in the
	 * word.
	 * 
	 * @return Whether all of the letters have been guessed or not
	 */
	public boolean isGuessed()
	{
		for (int i = 0; i < letters.length; i++)
		{
			if (letters[i] == '_')
				return false;
		}
		return true;
	}

	/**
	 * Check whether the user has used up all of their guesses.
	 * 
	 * @return Whether all of the user's guesses have been used
	 */
	public boolean isAllGuessesUsed()
	{
		return (guessesRemaining == 0);
	}

	/**
	 * Return the number of guesses remaining.
	 * 
	 * @return The number of guesses
	 */
	public int getGuessesRemaining()
	{
		return guessesRemaining;
	}

	/**
	 * Get the state of the guessed letters for the word.
	 * 
	 * @return The guessed letters
	 */
	public String getLetters()
	{
		return new String(letters);
	}

	/**
	 * Return whether the user has guessed the given letter or not.
	 * 
	 * @param letter
	 *            The letter to check
	 * @return Whether this letter has been guessed or not
	 */
	public boolean isGuessed(char letter)
	{
		letter = Character.toLowerCase(letter);
		return guessedLetters[letter - 'a'];
	}

	/**
	 * Get the current word that is being guessed or has been guessed.
	 * 
	 * @return The current word
	 */
	public String getCurrentWord()
	{
		return currentWord;
	}
}