import java.awt.List;
import java.awt.image.BufferedImage;
import java.awt.image.DataBuffer;
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Scanner;
import java.util.stream.Stream;
import javax.imageio.ImageIO;

public class ImageComparisson {


	public static int number;
	public static String[] S = new String[120001];
	public static ArrayList<String> list = new ArrayList<String>();

	public static void print ()
	{
		for (int i = 0 ; i < number ; i++ ) {
			System.out.println((i+1) +". "+S[i]);
		}
			System.out.println();



	}


    public static double compareImage(File fileA, File fileB, int percent) {

        double percentage = 0.0;
        try {
            // take buffer data from both image files //
        	BufferedImage biA = ImageIO.read(fileA);
			DataBuffer dbA = biA.getData().getDataBuffer();
			double sizeA = dbA.getSize();

			BufferedImage biB = ImageIO.read(fileB);
			DataBuffer dbB = biB.getData().getDataBuffer();
			double sizeB = dbB.getSize();

			double count = 0;

            // compare data-buffer objects //
			if (sizeA == sizeB) {

				for (int i = 0; i < sizeA; i++) {
					//check if pixel values are close enough (acceptable range of 15)
					if (Math.abs( ( dbA.getElem(i) - dbB.getElem(i))) <= 15 )  {
						count = count + 1;
					}

				}

               //calculate the percentage based on the similar pixels
				percentage = (count * 100) / sizeA;

			}
			else {

			}

		}
        catch (Exception e) {
				System.out.println("Failed to compare image files ... "  ) ;
				System.out.println(fileB.getPath());
				e.printStackTrace();
			}
        if (percentage >= percent)
        {

			System.out.println("Image file "+ fileB.getPath()+" is similar to reference file" );
			System.out.println("These images are "+  percentage + "% similar" );
			System.out.println();
			list.add(fileB.getPath());
			S[number] = fileB.getPath();
			number++;
        }
        return 0;
    }




	public static void main(String[] args) throws IOException {
		Scanner sc = new Scanner (System.in);
		Scanner sc2 = new Scanner (System.in);
		Scanner sc3 = new Scanner (System.in);
		System.out.println();
		File fileA = new File("Project_1_datasets\\2\\40694.jpg");
		System.out.println("The reference file is: "+ fileA.getPath());
		System.out.println();
		System.out.print("Enter percent of similarity to search for (0 to 100, recomended > 70 )  : ");
		int percent = sc.nextInt();
		while (percent < 0 || percent > 100)
		{
			System.out.println("Percentage entered not in range, choose a number between 0 to 100");
			percent = sc.nextInt();

		}
		System.out.println();
		int percents = percent;
		System.out.print("Searching for files "+ percents+"% similar to the file "+fileA.getPath());
		System.out.print(" , start search? (Y/N) : ");
		String S = sc2.nextLine();
		while (!S.equals("Y") && !S.equals("y"))
		{
			System.out.println("Please enter Y");
			S = sc2.nextLine();
		}
		System.out.println();
		System.out.println("Starting the search ...");
		System.out.println();
		try (Stream<Path> filePathStream=Files.walk(Paths.get("Project_1_datasets\\"))) {
		    filePathStream.forEach(filePath -> {
		        if (Files.isRegularFile(filePath)) {
		            File fileB = new File(filePath.toString());
		            compareImage(fileA ,fileB, percents);
		        }
		    });
		    System.out.println("Done searching");
		    System.out.println("Number of matches : "+ number);
		    System.out.println();
		    System.out.print("Print out the list of the " +number+" matching files (Y/N) : ");
		    String D = sc3.nextLine();
		    while (!D.equals("Y") && !D.equals("N") && !D.equals("n") && !D.equals("y")) {
		    	System.out.println("Please enter Y or N: ");
		    	D = sc3.nextLine();

		    }
		    System.out.println();
		    if (D.equals("Y") || D.equals("y")){
		    	print();

		    }

		    if (D.equals("N") || D.equals("n")){


		    }
		    System.out.println("Closing the program ...");
			sc.close();
			sc2.close();
			sc3.close();
		}
	 }
}