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This project holds utility classes to create or generate random data
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/**
 * The MIT License
 *
 * Copyright (C) 2015 Asterios Raptis
 *
 * 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 de.alpharogroup.random.number;

import de.alpharogroup.math.MathExtensions;
import de.alpharogroup.random.DefaultSecureRandom;
import de.alpharogroup.random.enums.RandomAlgorithm;

import java.security.SecureRandom;
import java.util.Objects;
import java.util.Random;

/**
 * Utility class for producing random primitive int types
 *
 * @version 1.1
 * @author Asterios Raptis
 */
public final class RandomIntFactory {

	/**
	 * The Method randomInt(int) gets an int to the spezified range. For example: if you put range
	 * to 10 the random int is between 0-9.
	 *
	 * @param range
	 *            The range
	 * @param algorithm
	 *            the random algorithm
	 * @return an int not greater then the range
	 */
	public static int randomInt(final int range, final RandomAlgorithm algorithm) {
		return RandomIntFactory.randomInt(range, Objects.requireNonNull(algorithm),
				DefaultSecureRandom.get());
	}

	/**
	 * The Method randomInt(int) gets an int to the spezified range. For example: if you put range
	 * to 10 the random int is between 0-9.
	 *
	 * @param range
	 *            The range
	 * @param algorithm
	 *            the random algorithm
	 * @param secureRandom
	 *            the secure random for int generation
	 * @return an int not greater then the range
	 */
	public static int randomInt(final int range, final RandomAlgorithm algorithm,
								SecureRandom secureRandom) {
		Objects.requireNonNull(algorithm);
		Objects.requireNonNull(secureRandom);
		switch (algorithm) {
			case MATH_ABS:
				return Math.abs(secureRandom.nextInt()) % range;
			case MATH_RANDOM:
				return (int) (Math.random() * range);
			case RANDOM:
				int random = new Random(System.currentTimeMillis()).nextInt() % range;
				return MathExtensions.isPositive(random) ? random : random * -1;
			case SECURE_RANDOM:
			default:
				return (int) (secureRandom.nextDouble() * range);
		}
	}

	/**
	 * The Method randomInt(int) gets an int to the spezified range. For example: if you put range
	 * to 10 the random int is between 0-9.
	 *
	 * @param range
	 *            The Range
	 * @param secureRandom
	 *            the secure random for int generation
	 * @return an int not greater then the range.
	 */
	public static int randomInt(final int range, SecureRandom secureRandom) {
		return randomInt(range, RandomAlgorithm.SECURE_RANDOM, secureRandom);
	}

	/**
	 * The Method randomInt() gets an int between the range 0-9.
	 *
	 * @param secureRandom
	 *            the secure random for int generation
	 *
	 * @return an int between the range 0-9.
	 */
	public static int randomInt(SecureRandom secureRandom) {
		return Objects.requireNonNull(secureRandom).nextInt();
	}

	/**
	 * The Method randomInt() gets an int between the range 0-9.
	 *
	 * @return an int between the range 0-9.
	 */
	public static int randomInt() {
		return RandomIntFactory.randomInt(DefaultSecureRandom.get());
	}

	/**
	 * The Method randomInt(int) gets an int to the spezified range. For example: if you put range
	 * to 10 the random int is between 0-9.
	 *
	 * @param range
	 *            The Range.
	 * @return an int not greater then the range.
	 */
	public static int randomInt(final int range) {
		return randomInt(range, DefaultSecureRandom.get());
	}

	/**
	 * Returns a random int between the range from minVolume and maxVolume with the
	 * Math.abs method.
	 *
	 * @param minVolume
	 *            the min volume
	 * @param maxVolume
	 *            the max volume
	 * @param secureRandom
	 *            the secure random for number generation
	 * @return A random int between the range from minVolume and maxVolume
	 */
	public static int randomIntBetween(int minVolume, int maxVolume, SecureRandom secureRandom) {
		return minVolume + randomInt(maxVolume - minVolume, RandomAlgorithm.SECURE_RANDOM,
				Objects.requireNonNull(secureRandom));
	}

	/**
	 * Returns a random int between the range from start and end.
	 *
	 * @param start
	 *            The int from where the range starts.
	 * @param end
	 *            The int from where the range ends.
	 * @param includeMin
	 *            if true than min value is included
	 * @param includeMax
	 *            if true than max value is included
	 * @param secureRandom
	 *            the secure random for generation
	 * @return A random int between the range from start and end.
	 */
	public static int randomIntBetween(final int start, final int end, final boolean includeMin,
									   final boolean includeMax, SecureRandom secureRandom) {
		int randomIntBetween = start + RandomIntFactory.randomInt(end - (start - 1), secureRandom);
		if (includeMin && !includeMax) {
			randomIntBetween = start + RandomIntFactory.randomInt(end - start, secureRandom);
		}
		if (!includeMin && includeMax && randomIntBetween == start) {
			randomIntBetween++;
		}
		if (!includeMin && !includeMax) {
			randomIntBetween = (start + 1) + RandomIntFactory.randomInt(end - (start + 1), secureRandom);
		}
		return randomIntBetween;
	}

	/**
	 * Returns a random int between the range from start and end.
	 *
	 * @param start
	 *            The int from where the range starts.
	 * @param end
	 *            The int from where the range ends.
	 * @return A random int between the range from start and end.
	 */
	public static int randomIntBetween(final int start, final int end) {
		return RandomIntFactory.randomIntBetween(start, end, true, false);
	}

	/**
	 * Returns a random int between the range from start and end.
	 *
	 * @param start
	 *            The int from where the range starts.
	 * @param end
	 *            The int from where the range ends.
	 * @param includeMin
	 *            if true than min value is included
	 * @param includeMax
	 *            if true than max value is included
	 * @return A random int between the range from start and end.
	 */
	public static int randomIntBetween(final int start, final int end, final boolean includeMin,
									   final boolean includeMax) {
		return RandomIntFactory.randomIntBetween(start, end, includeMin, includeMax, DefaultSecureRandom.get());
	}

	private RandomIntFactory() {
	}

}