import lab.Color;

import java.util.Random;

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

/**
 * Test case for the lab.Color class.
 *
 * @author Franck van Breugel
 */
public class ColorTest {
    /**
     * Tests the constructor and accessors for each RGB combination.
     */
    @Test
    public void testConstructorAndAccessors() {
	for (int r = Byte.MIN_VALUE; r <= Byte.MAX_VALUE; r++) {
	    for (int g = Byte.MIN_VALUE; g <= Byte.MAX_VALUE; g++) {
		for (int b = Byte.MIN_VALUE; b <= Byte.MAX_VALUE; b++) {
		    Color color = new Color((byte) r, (byte) g, (byte) b);
		    Assertions.assertNotNull("Constructed object is null", color);
		    Assertions.assertEquals("Accessor of red returns the incorrect value", r, color.getRed());
		    Assertions.assertEquals("Accessor of green returns the incorrect value", g, color.getGreen());
		    Assertions.assertEquals("Accessor of blue returns the incorrect value", b, color.getBlue());
		}
	    }
	}
    }
    
    /**
     * Tests that the constant BLACK is not null.
     */
    @Test
    public void testBLACK() {
	Assertions.assertNotNull("The constant BLACK is null", Color.BLACK);
    }

    /**
     * Tests the equals method.
     */
    @Test
    public void testEquals() {
	for (int r = Byte.MIN_VALUE; r <= Byte.MAX_VALUE; r++) {
	    for (int g = Byte.MIN_VALUE; g <= Byte.MAX_VALUE; g++) {
		for (int b = Byte.MIN_VALUE; b <= Byte.MAX_VALUE; b++) {
		    Color color = new Color((byte) r, (byte) g, (byte) b);
		    Object object = new Object();
		    Color copy = new Color((byte) r, (byte) g, (byte) b);
		    Assertions.assertFalse("null is equal to a Color", color.equals(null));
		    Assertions.assertFalse("An Object is equal to a Color", color.equals(object));
		    Assertions.assertTrue("A Color is not equal to itself", color.equals(color));
		    Assertions.assertTrue("A Color is not equal to another color with the same RGB values", color.equals(copy));
		}
	    }
	}
    }
    
    /**
     * Tests the equals method for different Color objects.
     */
    @Test
    public void testEqualsRandomly() {
	final int CASES = 100000000;
	Random random = new Random();
	for (int c = 0; c < CASES; c++) {
	    byte b = (byte) (Byte.MIN_VALUE + random.nextInt(Byte.MAX_VALUE - Byte.MIN_VALUE));
	    byte r = (byte) (Byte.MIN_VALUE + random.nextInt(Byte.MAX_VALUE - Byte.MIN_VALUE));
	    byte g = (byte) (Byte.MIN_VALUE + random.nextInt(Byte.MAX_VALUE - Byte.MIN_VALUE));
	    Color one = new Color(r, g, b);
	    b = (byte) (Byte.MIN_VALUE + random.nextInt(Byte.MAX_VALUE - Byte.MIN_VALUE));
	    r = (byte) (Byte.MIN_VALUE + random.nextInt(Byte.MAX_VALUE - Byte.MIN_VALUE));
	    g = (byte) (Byte.MIN_VALUE + random.nextInt(Byte.MAX_VALUE - Byte.MIN_VALUE));
	    Color other = new Color(r, g, b);
	    Assertions.assertEquals("Comparison of two Colors failed", one.equals(other), 
				    one.getRed() == other.getRed() && one.getGreen() == other.getGreen() && one.getBlue() == other.getBlue());
	}
    }
}