package mm.structures;

import java.util.Arrays;
import java.util.Random;

/**
 * Square matrix (n x n) of m (colorCount) colors.
 */
public class ColorField extends Matrix {

    private int n, colorCount;
    private int[][] neighbourMask;
    private ColorPixel[] colors;

    /**
     * Initialize mm.structures.ColorField as n x n matrix using given colors array as colors.
     *
     * @param n      - Dimension of matrix.
     * @param colors - Colors to be used in field.
     */
    public ColorField(int n, ColorPixel[] colors) {
        super(n);
        init(colors, true);
    }

    private ColorField(int n, ColorPixel[] colors, int[][] neighbourMask) {
        super(n);
        this.neighbourMask = neighbourMask;
        init(colors, false);
    }

    /**
     * Initialize mm.structures.ColorField as n x n matrix using given colors array as colors.
     *
     * @param array  - Array representing the field matrix.
     * @param colors - Colors to be used in field.
     */
    private ColorField(int[][] array, ColorPixel[] colors) {
        super(array);
        colors = colors != null ? colors : new ColorPixel[0];
        init(colors, true);
    }

    /**
     * Initialize colors array and color map (array of ints representing colors).
     * @param colors - Colors to be used in field.
     */
    private void init(ColorPixel[] colors, boolean calculateNeighbourMask) {
        this.n = super.n;
        this.colors = colors;
        this.colorCount = colors.length;
        // Set codes for each color.
        for(int i = 0; i < colorCount; i++) {
            colors[i].setCode(i);
        }
        if(calculateNeighbourMask) {
            // Calculate neighbourMask array in advance, used to improve performance
            //  compared to calculating indices for every `getNeighbours` lookup.
            neighbourMask = new int[super.length][8];
            for (int i = 0, index = 0; i < m; i++) {
                for (int j = 0; j < n; j++, index++) {
                    for (int ii = i - 1, ind = 0; ii <= i + 1; ii++) {
                        for (int jj = j - 1; jj <= j + 1; jj++) {
                            if (ii == i && jj == j) {
                                continue;
                            }
                            neighbourMask[index][ind++] =
                                    ((ii < 0 || ii >= m) || (jj < 0 || jj >= n))
                                            ? -1 : indexOf(ii, jj);
                        }
                    }
                }
            }
        }
    }

    public int getN() {
        return n;
    }

    public int getColorCount() {
        return colorCount;
    }

    public ColorPixel[] getColors() {
        return colors;
    }

    /**
     * Find values of neighbours of (i, j).
     *
     * @param i - mm.structures.Matrix row.
     * @param j - mm.structures.Matrix column.
     * @return - Vector (1x8) of neighbours. If neighbour index is out of bounds, -1 is used as value.
     */
    public int[] getNeighbours(int i, int j) {
        return getNeighbours(indexOf(i, j));
    }

    public int[] getNeighbours(int i) {
        int[] map = neighbourMask[i];
        int[] neighbours = new int[8];
        int existsCount = 0;
        for (int ii = 0; ii < 8; ii++) {
            if(map[ii] != -1) {
                neighbours[existsCount++] = a[map[ii]];
            }
        }
        return Arrays.copyOf(neighbours, existsCount);
    }

    public ColorField updateNeighbours() {
        final ColorField cf = new ColorField(n, colors, neighbourMask);
        final Random r = new Random();

        for (int i = 0; i < length; i++) {
                    int[] neigbours = getNeighbours(finalI);
                    cf.setElement(finalI, neigbours[r.nextInt(neigbours.length)]);
        }

        return cf;
    }

    public static ColorField GenerateField(int n, ColorPixel[] colors) {
        ColorField cf = new ColorField(n, colors);
        Random r = new Random();
        for(int i = 0; i < cf.length; i++) {
            cf.setElement(i, colors[r.nextInt(cf.colorCount)].getCode());
        }
        return cf;
    }
}

@@ -3648,32 +3648,155 @@
  length; i++) %7B%0A
+            final int finalI = i;%0A            new Thread() %7B%0A                @Override%0A                public void run() %7B%0A
                 
@@ -3923,16 +3923,55 @@
 gth)%5D);%0A
+                %7D%0A            %7D.run();%0A
         

use threads to update ColorField