FormuAvatar.java

package Challenge_174_Intermediate;

import java.awt.Color;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import javax.imageio.ImageIO;

public class ForumAvatar{

	private static byte[] hash;
	private static Color[] colors;
	private static String input = "MrP_123";

	public static void main(String[] args){
		try{
			byte[] bytes = input.getBytes("UTF-8");
			MessageDigest md = MessageDigest.getInstance("MD5");
			hash = md.digest(bytes);
		}catch(UnsupportedEncodingException | NoSuchAlgorithmException e){
			e.printStackTrace();
		}

		//gets all needed colors
		getColors();

		//generates 1/4 of the image
		Color[] image = new Color[16];
		image = makeImage(image);

		//completes and saves the whole image
		saveFullImage(image);
	}

	private static void getColors(){
		colors = new Color[5];	//MD5 hash is 16 bytes --> 5 full colors
		int index = 0;
		for(int i = 0; i < hash.length - 1; i += 3){
			int r = ((Byte) hash[i]).intValue() + 128;
			int g = ((Byte) hash[i + 1]).intValue() + 128;
			int b = ((Byte) hash[i + 2]).intValue() + 128;

			colors[index] = new Color(r, g, b);
			index++;
		}
	}

	private static Color[] makeImage(Color[] image){
		//255 (byte max value) / 5 (amount of colors) = 51
		for(int i = 0; i < image.length; i++){
			if((((Byte) hash[i]).intValue() + 128) < 51){
				image[i] = colors[0];
			}else if((((Byte) hash[i]).intValue() + 128) < 102){
				image[i] = colors[1];
			}else if((((Byte) hash[i]).intValue() + 128) < 153){
				image[i] = colors[2];
			}else if((((Byte) hash[i]).intValue() + 128) < 204){
				image[i] = colors[3];
			}else{
				image[i] = colors[4];
			}
		}

		return image;
	}

	private static void saveFullImage(Color[] image){
		Color[] imageWhole = add(add(image, mirrorImage(image)), mirrorImage(add(image, mirrorImage(image))));

		saveImage(imageWhole);
	}

	private static void saveImage(Color[] image){
		int side = (int) Math.sqrt(image.length);

		BufferedImage img = new BufferedImage(side, side, BufferedImage.TYPE_INT_RGB);
		for(int x = 0; x < side; x++){
			for(int y = 0; y < side; y++){
				img.setRGB(x, y, image[x + y * side].getRGB());
			}
		}

		File path = new File(System.getProperty("user.home") + "/Desktop/ForumAvatar-" + input + ".png");
		try{
			ImageIO.write(img, "png", path);
		}catch(IOException e){
			e.printStackTrace();
		}
	}

	private static Color[] mirrorImage(Color[] image){
		Color[] result = new Color[image.length];

		for(int i = 0; i < image.length / 2; i++){
			Color temp = image[i];
			result[i] = image[image.length - i - 1];
			result[image.length - i - 1] = temp;
		}
		return result;
	}

	private static Color[] add(Color[] c1, Color[] c2){
		int len1 = c1.length;
		int len2 = c2.length;

		Color[] c = new Color[len1 + len2];
		System.arraycopy(c1, 0, c, 0, len1);
		System.arraycopy(c2, 0, c, len1, len2);
		return c;
	}
}