package com.prgguru.webapp;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FilenameFilter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;

import net.semanticmetadata.lire.DocumentBuilder;
import net.semanticmetadata.lire.DocumentBuilderFactory;
import net.semanticmetadata.lire.imageanalysis.FCTH;

import org.apache.commons.codec.binary.Base64;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.util.BytesRef;

public class ManipulateImage {

	static class ImageInImageDatabase {

		public String fileName;
		public double[] fcthFeatureVector;
		public double distanceToSearchImage;
	}

	static class ImageComparator implements Comparator<ImageInImageDatabase> {

		@Override
		public int compare(ImageInImageDatabase object1,
				ImageInImageDatabase object2) {
			if (object1.distanceToSearchImage < object2.distanceToSearchImage) {
				return -1;
			} else if (object1.distanceToSearchImage > object2.distanceToSearchImage) {
				return 1;
			} else {
				return 0;
			}
		}
	}

	public static double[] getFCTHFeatureVector(String fullFilePath)
			throws FileNotFoundException, IOException {

		DocumentBuilder builder = DocumentBuilderFactory
				.getFCTHDocumentBuilder();
		FileInputStream istream = new FileInputStream(fullFilePath);
		Document doc = builder.createDocument(istream, fullFilePath);
		istream.close();
		FCTH fcthDescriptor = new FCTH();
		String fieldname = ((Field) doc.getFields().get(0)).name();
		BytesRef br = doc.getBinaryValue(fieldname);
		fcthDescriptor.setByteArrayRepresentation(br.bytes, br.offset,
				br.length);
		return fcthDescriptor.getDoubleHistogram();

	}

	public static double calculateEuclideanDistance(double[] vector1,
			double[] vector2) {

		double innerSum = 0.0;
		for (int i = 0; i < vector1.length; i++) {
			innerSum += Math.pow(vector1[i] - vector2[i], 2.0);
		}

		return Math.sqrt(innerSum);

	}

	// Decode String into an Image
	public static String convertStringtoImage(String encodedImageStr,
			String fullPath, String filename) {
		String resultName = "";
		try {
			// Decode String using Base64 Class
			byte[] imageByteArray = Base64.decodeBase64(encodedImageStr);

			// Write Image into File system - Make sure you update the path
			FileOutputStream imageOutFile = new FileOutputStream(fullPath);
			imageOutFile.write(imageByteArray);

			imageOutFile.close();

			String[] args = new String[2];
			// path of source
			args[0] = "src/sourceimagesfolder/";
			// photo taken
			//args[1] = fullPath;
			args[1] = "WebContent/UploadedImages/example1.jpg";
			if (args.length != 2) {

				System.out
						.println("This application requires two parameters: "
								+ "the name of a directory containing JPEG images, and a file name of a JPEG image.");
				return "";

			}

			String imageDatabaseDirectoryName = args[0];
			String searchImageFilePath = args[1];
			double[] searchImageFeatureVector = getFCTHFeatureVector(searchImageFilePath);

			System.out.println("Search image FCTH vector: "
					+ Arrays.toString(searchImageFeatureVector));

			ArrayList<ImageInImageDatabase> database = new ArrayList();

			File directory = new File(imageDatabaseDirectoryName);

			FilenameFilter filter = new FilenameFilter() {
				public boolean accept(File dir, String name) {
					return name.endsWith(".jpg") || name.endsWith(".jpeg");
				}
			};

			String[] fileNames = directory.list(filter);

			for (String fileName : fileNames) {

				double[] fcthFeatureVector = getFCTHFeatureVector(imageDatabaseDirectoryName
						+ "\\" + fileName);
				double distanceToSearchImage = calculateEuclideanDistance(
						fcthFeatureVector, searchImageFeatureVector);

				ImageInImageDatabase imageInImageDatabase = new ImageInImageDatabase();

				imageInImageDatabase.fileName = fileName;
				imageInImageDatabase.fcthFeatureVector = fcthFeatureVector;
				imageInImageDatabase.distanceToSearchImage = distanceToSearchImage;

				database.add(imageInImageDatabase);

			}

			Collections.sort(database, new ImageComparator());

			for (ImageInImageDatabase result : database) {

				System.out.println("Distance "
						+ Double.toString(result.distanceToSearchImage) + ": "
						+ result.fileName);
			}

			System.out.println("Image Successfully Stored");
		} catch (FileNotFoundException fnfe) {
			System.out.println("Image Path not found" + fnfe);
		} catch (IOException ioe) {
			System.out.println("Exception while converting the Image " + ioe);
		}
		return resultName;
	}

	public static void main(String[] args) throws FileNotFoundException,
			IOException {

		args = new String[2];
		// path of source
		args[0] = "src/sourceimagesfolder/";
		// photo taken
		args[1] = "WebContent/UploadedImages/example1.jpg";
		if (args.length != 2) {

			System.out
					.println("This application requires two parameters: "
							+ "the name of a directory containing JPEG images, and a file name of a JPEG image.");
			return;

		}

		String imageDatabaseDirectoryName = args[0];
		String searchImageFilePath = args[1];
		double[] searchImageFeatureVector = getFCTHFeatureVector(searchImageFilePath);

		System.out.println("Search image FCTH vector: "
				+ Arrays.toString(searchImageFeatureVector));

		ArrayList<ImageInImageDatabase> database = new ArrayList();

		File directory = new File(imageDatabaseDirectoryName);

		FilenameFilter filter = new FilenameFilter() {
			public boolean accept(File dir, String name) {
				return name.endsWith(".jpg") || name.endsWith(".jpeg");
			}
		};

		String[] fileNames = directory.list(filter);

		for (String fileName : fileNames) {

			double[] fcthFeatureVector = getFCTHFeatureVector(imageDatabaseDirectoryName
					+ "\\" + fileName);
			double distanceToSearchImage = calculateEuclideanDistance(
					fcthFeatureVector, searchImageFeatureVector);

			ImageInImageDatabase imageInImageDatabase = new ImageInImageDatabase();

			imageInImageDatabase.fileName = fileName;
			imageInImageDatabase.fcthFeatureVector = fcthFeatureVector;
			imageInImageDatabase.distanceToSearchImage = distanceToSearchImage;

			database.add(imageInImageDatabase);

		}

		Collections.sort(database, new ImageComparator());

		for (ImageInImageDatabase result : database) {

			System.out.println("Distance "
					+ Double.toString(result.distanceToSearchImage) + ": "
					+ result.fileName);

		}

	}

}