import javax.swing.*;
import java.awt.*;
import java.awt.image.*;
import java.text.DecimalFormat;
import java.text.FieldPosition;
import java.io.*;

class gait {

	// No. at start of gait cycle
	private static int start = 62;

	public static void main(String args[]) {

		gait prog = new gait();
	}

	public gait() {

		System.out.println("Gait program started");

		// Make the next filename
		//String file = "./moments.csv";

		PrintStream ps = null;
		try { ps = new PrintStream(new FileOutputStream(new File("./moments.csv"))); } catch(Exception e) {};

		for(int person = 13; person < 18; person++) {
			
			for (int sequence = 0; sequence < 7; sequence++) {

				String path = null;
				String fileName = null;

				StringBuffer sb = new StringBuffer();
				DecimalFormat format = new DecimalFormat("000");
				format.format(person, sb, new FieldPosition(0));

				path = "./008a" + sb + "s";
				fileName = "008a" + sb + "s";

				sb = new StringBuffer();
				format = new DecimalFormat("00");
				format.format(sequence, sb, new FieldPosition(0));

				path = path + sb + "L/";
				fileName = fileName + sb + "L_";

				System.out.println(path);

				FileReader reader = null;
				try {
					reader = new FileReader(path + "start.txt");
				}
				catch(FileNotFoundException e) {
					System.out.println(e);
				}
				BufferedReader br = new BufferedReader(reader);
				String thestart = null;
				try { thestart = br.readLine(); } catch(IOException e) { System.out.println(e); }

				System.out.println("start = " + thestart);
				start = Integer.parseInt(thestart);


				// Arrays for results
				double I_one[] = new double[30];
		   	 	double I_two[] = new double[30];
		  	 	double I_eight[] = new double[30];
  	 	
		  	 	int pixels[][] = new int[30][];
		  	 	int width[] = new int[30];
		  	 	int height[] = new int[30];

				for(int i = start; i < (start + 30); i++) {

					sb = new StringBuffer();
					format = new DecimalFormat("0000");
					format.format(i, sb, new FieldPosition(0));
		
					// Make the next filename
					String file = path + fileName + sb + "_scaled.png";

					System.out.println(file);
			
					// A helpful index no
					int ind = i-start;

					// Create an imageicon and get the image from it
					ImageIcon iconIm = new ImageIcon(file);
					Image image = iconIm.getImage();
					while(iconIm.getImageLoadStatus() != MediaTracker.COMPLETE);

					// Get width and height
					width[ind] = iconIm.getIconWidth();
					height[ind] = iconIm.getIconHeight();

					// Initialise array to store pixels
					pixels[ind] = new int[width[ind]*height[ind]];

					// Create a pixelgrabber to grab the pixels
					PixelGrabber grabber = new PixelGrabber(image, 0, 0, width[ind], height[ind], pixels[ind], 0, width[ind]);

					try {
						grabber.grabPixels();
					}
					catch(InterruptedException e) {
						System.out.println(e);
					}
				}
		
				System.out.println("Images loaded");
		
				for(int i = 0; i < 30; i++) {

					int centre[] = new int[2];

					// Precalculate centre of mass
					centreOfMass(pixels[i], centre, width[i], height[i]);

					// Precalculate moments
					//long centralised02 = centralisedMoment(pixels[i] ,0 , 2, centre[0], centre[1], width[i], height[i]);
					//long centralised20 = centralisedMoment(pixels[i] ,2 , 0, centre[0], centre[1], width[i], height[i]);
					//long centralised11 = centralisedMoment(pixels[i] ,1 , 1, centre[0], centre[1], width[i], height[i]);
					//long moment00 = moment(pixels[i], 0, 0, width[i], height[i]);
			
					// Faster moment calculation
					long centralised02 = 0;
					long centralised20 = 0;
					long centralised11 = 0;
					long moment00 = 0;
			
					for(int j = 0; j < width[i]; j++) {
						for(int k = 0; k < height[i]; k++) {
							if(pixels[i][(k*width[i])+j] != 0xff000000) {
						
								centralised02 += Math.pow((k-centre[1]), 2);
								centralised20 += Math.pow((j-centre[0]), 2);
								centralised11 += (j-centre[0]) * (k-centre[1]);
								moment00++;
							}
						}
					}
			
					I_one[i] = ((double)(centralised20 + centralised02)) / ((double)Math.pow(moment00, 2));
			
					I_two[i] = (double)Math.pow((centralised20 - centralised02), 2) + (double)Math.pow((4 * centralised11), 2);
					I_two[i] /= (double)Math.pow(moment00, 4);
			
					I_eight[i] = (double)(centralised20 * centralised02) - (double)Math.pow(centralised11, 2);
					I_eight[i] /= (double)Math.pow(moment00, 4);

					//I_one[i] = Ione(pixels[i], width[i], height[i], centre[0], centre[1]);
					//I_two[i] = Itwo(pixels[i], width[i], height[i], centre[0], centre[1]);
					//I_eight[i] = Ieight(pixels[i], width[i], height[i], centre[0], centre[1]);

					System.out.println(I_one[i] + "," + I_two[i] + "," + I_eight[i]);
					
				}

				// calcerate mean and variance
				double sumI_one = 0;  // sum of all the elements
				double sumI_two = 0;
				double sumI_eight = 0;
				double sumI_oneSq = 0;
				double sumI_twoSq = 0;
				double sumI_eightSq = 0;

				for (int i=0; i<I_one.length; i++) {

					sumI_one += I_one[i];
					sumI_two += I_two[i];
					sumI_eight += I_eight[i];
					sumI_oneSq += I_one[i]*I_one[i];
					sumI_twoSq += I_two[i]*I_two[i];
					sumI_eightSq += I_eight[i]*I_eight[i];
				}

				float huMean1 = (float) (sumI_one / I_one.length);
				float huMean2 = (float) (sumI_two / I_two.length);
				float huMean8 = (float) (sumI_eight / I_eight.length);

				float huVariance1 = (float) ((I_one.length * sumI_oneSq) - (sumI_one*sumI_one)) / (I_one.length * I_one.length);
				float huVariance2 = (float) ((I_two.length * sumI_twoSq) - (sumI_two*sumI_two)) / (I_two.length * I_two.length);
				float huVariance8 = (float) ((I_eight.length * sumI_eightSq) - (sumI_eight*sumI_eight)) / (I_eight.length * I_eight.length);

				ps.println(huMean1 + "," + huMean2 + "," + huMean8 + "," + huVariance1 + "," + huVariance2 + "," + huVariance8);
				
			}
		}
		ps.close();
	}

	// Find the centre of mass of an image
	private void centreOfMass(int pixels[], int results[], int width, int height) {

		int a = 0;
		int b = 0;
		int count = 0;
	
		for(int i = 0; i < width; i++) {
			for(int j = 0; j < height; j++) {
				if(pixels[(j*width)+i] != 0xff000000) {
					a += i;
					b += j;
					count += 1;
				}
			}
		}
	
		results[0] = (int)(((float)a)/((float)count));
		results[1] = (int)(((float)b)/((float)count));

	}
}