/*
 * Copyright 2005,2006 WSO2, Inc. http://www.wso2.org
 *
 * 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 org.wso2.wsas.example;

import java.util.Random;

/**
 * WSO2GameService is a Simple Guessing Game that will check your ability to guess 
 * and the knowledge of the future. At the start of the game there will be a number selected
 * by the service <code>machineGuess</code> and to win the game user have to guess
 * that number using his guessing power and with the minimum tries. User will be given 
 * 10 maximum tries ( This can be configurable by calling  <code>startGame(int, int)</code> ) to 
 * guess. Game end either with, if user fails to guess it within the number of tries (user loosing)
 * or user was able to guess the number less than or equal number of maximum tries (user winning).
 * <p>
 * How to play.
 * </p>
 * <ol>
 * 		<ul>1) Start the game by calling the <code>startGame()</code></ul>
 * 		<ul>2) Optionally user can set the range immediately after starting the game by calling 
 *           <code>startGame(int startNumber, int endNumber )</code></ul>
 * 		<ul>3) Try the guess by calling <code>guess(int)</code> until game over.</ul>
 * 		<ul>4) Optionally user can end the game at any time after start calling the <code>endGame()</code></ul>
 * 		<ul></ul>
 * </ol>
 * 
 * Game will report the results after each guess.  
 * 
 */
public class WSO2GameService {
	

	/**
	 * Number to store the machine guess at the start of the game.
	 */
	private int machineGuess;
	
	/**
	 * Maximum number of attempts that users can try the game
	 */
	private final int MAX_USER_ATTEMPTS = 10;
	
	/**
	 * Counter initialized to zero at the start to counter user tries
	 */
	private int tryCounter = 0;

	/**
	 * Default range for the number guess.
	 * Can be override by the <code>startGame(int, int)</code>
	 */
	private final int[] defalutRange = {1,20};
	

	/**
	 * Start the WSO2GameService
	 * This will initiate the game with default number range
	 */
	public String startGame() {
		String message;
		try {
			message = displayStartingMessage();
			generateRandom(defalutRange[0], defalutRange[1]);
		} catch (Exception e) {
			return "Error, Not Started";
		}
		return message;
	}
	
	
	/**
	 * Start the WSO2GameService
	 * This will initiate the game with custom number range
	 * @param startNumber : starting number of the range
	 * @param endNumber : ending number of the range
	 */
	public String startGameWithCustomRange(int startNumber, int endNumber ){
		String message;
		try {
			message = displayStartingMessage();
			generateRandom(startNumber, endNumber);
		} catch (Exception e) {
			return "Error, Not Started";
		}
		return message;
	}
	
	
	/**
	 * Match the user guess against the machine guess
	 * @param guess  : user guess
	 * @return result of the try
	 */
	public String guess(int guess) {
		StringBuffer stringResult = new StringBuffer();
		if(tryCounter == MAX_USER_ATTEMPTS){
			stringResult.append(" User has exeed all Given tries !! You LOOSE");
			stringResult.append(" The Machine guess was : "+ machineGuess);
			System.out.print(stringResult);
		} else if (guess == machineGuess) {
			stringResult.append("\nUser Guess : " + guess+ " Guess Succeed !! You WIN !!");
			System.out.println(stringResult);
		}else{
			stringResult.append("\nUser Guess : " + guess+" Bad Guess !! Try Again !!");
			System.out.println(stringResult);
			tryCounter++;
		}
		return stringResult.toString();
	}
	
	
	/**
	 * End the game
	 * This will clear the machine guess also
	 */
	public String  endGame() {
		String message;
		try {
			tryCounter = 0;
			message = "\nWSO2GameService Terminated !! \n\n";
			System.out.println(message);
		} catch (Exception e) {
			return "Error, Not Stopped";
		}
		return message;
	}
	

	/**
	 * Generate the random number as the machine guess
	 * @param startValue  : start value for the number range
	 * @param range  : number range 
	 */
	private void generateRandom(int startValue, int range){
		Random random = new Random();
		machineGuess = random.nextInt(range) + startValue;
	}
	
	
	/**
	 * Display starting message.
	 */
	private String displayStartingMessage() {
		return "Welcome to the WSO2 Game Service,\n Machine Guess Initiating...  !!";
	}
	
}