package org.lucares.utils;

import java.text.MessageFormat;
import java.util.Objects;

public class Preconditions {
	public static void checkEven(final long value, final String message) {
		if (value % 2 != 0) {
			throw new IllegalStateException(message + ". Was: " + value);
		}
	}

	/**
	 *
	 * @param a
	 * @param b
	 * @param message formatted with {@link MessageFormat}
	 * @param args
	 */
	public static void checkGreater(final long a, final long b, final String message, final Object... args) {

		if (a <= b) {
			throw new IllegalStateException(MessageFormat.format(message, args) + " Expected: " + a + " > " + b);
		}
	}

	/**
	 *
	 * @param a
	 * @param b
	 * @param message formatted with {@link MessageFormat}
	 * @param args
	 * @throws IllegalStateException if {@code a} is not greater or equal to
	 *                               {@code b}
	 */
	public static void checkGreaterOrEqual(final long a, final long b, final String message, final Object... args) {
		if (a < b) {
			throw new IllegalStateException(MessageFormat.format(message, args) + " Expected: " + a + " >= " + b);
		}
	}

	public static void checkSmaller(final long a, final long b, final String message, final Object... args) {
		if (a >= b) {
			throw new IllegalStateException(MessageFormat.format(message, args) + " Expected: " + a + " < " + b);
		}
	}

	public static void checkEqual(final Object actual, final Object expected) {
		checkEqual(actual, expected, "expected {0} is equal to {1}", actual, expected);
	}

	/**
	 * Check that the given values are equal. The check is done with
	 * {@link Objects#equals(Object, Object)}
	 *
	 * @param actual   the actual value
	 * @param expected the expected value
	 * @param message  formatted with {@link MessageFormat}
	 * @param args     arguments for the message
	 * @throws IllegalStateException if {@code actual} is not equal to
	 *                               {@code expected}
	 */
	public static void checkEqual(final Object actual, final Object expected, final String message,
			final Object... args) {
		if (!Objects.equals(actual, expected)) {
			throw new IllegalStateException(
					MessageFormat.format(message, args) + " Expected: " + actual + " equals " + expected);
		}
	}

	/**
	 * Check that the given value is true.
	 *
	 * @param actual  must be true
	 * @param message formatted with {@link MessageFormat}
	 * @param args    arguments for the message
	 * @throws IllegalStateException if {@code actual} is not true
	 */
	public static void checkTrue(final boolean actual, final String message, final Object... args) {
		checkEqual(actual, true, message, args);
	}

	/**
	 * Check that the given value is false.
	 *
	 * @param actual  must be false
	 * @param message formatted with {@link MessageFormat}
	 * @param args    arguments for the message
	 * @throws IllegalStateException if {@code actual} is not false
	 */
	public static void checkFalse(final boolean actual, final String message, final Object... args) {
		checkEqual(actual, false, message, args);
	}

	public static void checkNull(final Object actual, final String message, final Object... args) {
		if (actual != null) {
			throw new IllegalStateException(MessageFormat.format(message, args));
		}
	}

}