package sk.paz1b.practicals.task5;

import java.awt.*;
import java.awt.image.*;
import java.io.*;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.Queue;

import javax.imageio.*;

public class AnalyzatorSkenu2 {

	/**
	 * Privatna na ulozenie suradnic pixelu (riadok, stlpec)
	 */
	private static class Pixel {
		int riadok;
		int stlpec;

		public Pixel(int riadok, int stlpec) {
			this.riadok = riadok;
			this.stlpec = stlpec;
		}
	}

	/**
	 * Naskenovany obrazok
	 */
	private BufferedImage obrazok;

	/**
	 * Sirka nacitaneho obrazka
	 */
	private int sirka;

	/**
	 * Vyska nacitaneho obrazka
	 */
	private int vyska;

	/**
	 * Hustota buniek - podiel plochy pokrytej bunkami k ploche skenu
	 */
	private double hustotaBuniek;

	private int pocetBuniek;

	private boolean[][] poleBunky;

	private int[][] smery = { { 0, 1 }, { 0, -1 }, { 1, 0 }, { -1, 0 }, { 1, 1 }, { 1, -1 }, { -1, 1 }, { -1, -1 } };

	/**
	 * Vytvori novy analyzator skenu buniek a spusti zakladnu analyzu
	 *
	 * @param nazovSuboru nazov suboru so skenom buniek
	 */
	public AnalyzatorSkenu2(String nazovSuboru) {
		try {
			obrazok = ImageIO.read(new File(nazovSuboru));
			sirka = obrazok.getWidth();
			vyska = obrazok.getHeight();

		} catch (IOException e) {
			System.err.println("Subor " + nazovSuboru + " sa nepodarilo nacitat.");
		}

		analyzuj();
	}

	/**
	 * Vrati, ci je pixel na suradniciach [x, y] pixelom bunky.
	 */
	private boolean jePixelBunky(int x, int y) {
		Color pixel = new Color(obrazok.getRGB(x, y));
		return !pixel.equals(Color.black);
	}

	/**
	 * Vypocita hustotu buniek
	 */
	private void vypocitajHustotuBuniek() {
		int pocetBunkovychPixelov = 0;
		for (int y = 0; y < vyska; y++)
			for (int x = 0; x < sirka; x++)
				if (jePixelBunky(x, y))
					pocetBunkovychPixelov++;

		hustotaBuniek = pocetBunkovychPixelov / ((double) sirka * vyska);
	}

	/**
	 * Realizuje zakladnu analyzu obrazka so skenom buniek
	 */
	private void analyzuj() {
		vypocitajHustotuBuniek();
		poleBunky = new boolean[sirka][vyska];
		for (int y = 0; y <= vyska - 1; y++)
			for (int x = 0; x <= sirka - 1; x++) {
				if (jePixelBunky(x, y)) {
					poleBunky[x][y] = true;
				}
			}

		for (int y = 0; y <= vyska - 1; y++)
			for (int x = 0; x <= sirka - 1; x++) {
				if (poleBunky[x][y]) {
					pocetBuniek++;
					Pixel p = new Pixel(x, y);
					pixelPatriBunke(p);

				}
			}
	}

	private boolean somVRozsahu(Pixel pixel) {
		if (pixel.riadok >= 0 && pixel.riadok < vyska - 1 && pixel.stlpec >= 0 && pixel.stlpec < sirka - 1) {
			return true;
		}
		return false;
	}

	public void pixelPatriBunke(Pixel start) {
		Queue<Pixel> rad = new LinkedList<Pixel>();
		rad.offer(start);
		while (!rad.isEmpty()) {
			Pixel pixelBunky = rad.poll();
			if (somVRozsahu(pixelBunky)) {
				for (int smer = 0; smer < 8; smer++) {
					Pixel sused = new Pixel(pixelBunky.riadok + smery[smer][0], pixelBunky.stlpec + smery[smer][1]);
					if (somVRozsahu(sused)) {
						if ((poleBunky[sused.riadok][sused.stlpec] == true)) {
//na tomto mieste to vzdy hodi error indexOutOfBoundsException: 600
							poleBunky[sused.riadok][sused.stlpec] = false;
							rad.offer(sused);
						}
					}

				}
			}
		}

	}

	/**
	 * Vrati pocet buniek na obrazku
	 */
	public int getPocetBuniek() {
		return pocetBuniek;
	}

	/**
	 * Vrati hustotu buniek (pomer bunkovych pixelov k vsetkym pixelom)
	 */
	public double getHustotaBuniek() {
		return hustotaBuniek;
	}

	public static void main(String[] args) {
		AnalyzatorSkenu2 analyzator = new AnalyzatorSkenu2("SkenBuniek03.png");
		System.out.println("Hustota buniek: " + (analyzator.getHustotaBuniek() * 100) + " %");
		System.out.println("Pocet buniek: " + analyzator.getPocetBuniek());

	}
}