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/*
 * The MIT License (MIT)
 * 
 * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package com.camilstaps.die;

import org.junit.After;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;
import static org.junit.Assert.*;

/**
 * Test the Die class
 * @author Camil Staps, s4498062
 */
public class DieTest {
    
    private static final int PLAYERS = 100;
    private static final int THROWS = 100;
    
    private static final double ACCEPTABLE_LOWER_BOUND = 0.95;
    private static final double ACCEPTABLE_UPPER_BOUND = 1.05;
    
    public DieTest() {
    }
    
    @BeforeClass
    public static void setUpClass() {
    }
    
    @AfterClass
    public static void tearDownClass() {
    }
    
    @Before
    public void setUp() {
    }
    
    @After
    public void tearDown() {
    }

    /**
     * Test that the probabilities for every different possible outcome are more or less close to the expected probability
     * Accuracy of this test depends on PLAYERS, THROWS, ACCEPTABLE_LOWER_BOUND and ACCEPTABLE_UPPER_BOUND
     * 
     * With non-thread safe solutions, this test most of the time fails. With thread-safe solutions, the test normally passes.
     */
    @Test
    public void correctProbabilities() {
        // Start players
        Die die = new Die();
        Player players[] = new Player[PLAYERS];
        Thread threads[] = new Thread[PLAYERS];
        for (int i = 0; i < PLAYERS; i++) {
            players[i] = new Player("Player " + i, die, THROWS);
            threads[i] = new Thread(players[i]);
            threads[i].start();
        }
        
        // Gather data
        int pips_counts[] = new int[Die.MAX_PIPS];
        for (int i = 0; i < PLAYERS; i++) {
            try {
                threads[i].join();
                for (int p : players[i].getPipss()) {
                    pips_counts[p - 1]++;
                }
            } catch (InterruptedException e) {
                System.err.println(e);
            }
        }
        
        // Verification
        int lower_bound = (int) (PLAYERS * THROWS / Die.MAX_PIPS * ACCEPTABLE_LOWER_BOUND);
        int upper_bound = (int) (PLAYERS * THROWS / Die.MAX_PIPS * ACCEPTABLE_UPPER_BOUND);
        System.out.println("Normal: " + PLAYERS * THROWS / Die.MAX_PIPS);
        System.out.println("Lower bound: " + lower_bound + " (" + ACCEPTABLE_LOWER_BOUND + ")");
        System.out.println("Upper bound: " + upper_bound + " (" + ACCEPTABLE_UPPER_BOUND + ")");
        for (int i = 0; i < Die.MAX_PIPS; i++) {
            System.out.println("Number of " + i + ": " + pips_counts[i]);
            assertTrue("Number of " + i + " out of range", pips_counts[i] > lower_bound && pips_counts[i] < upper_bound);
        }
    }
}