/**
    * FaceTracker Licence
    * -------------------
    * (Academic, non-commercial, not-for-profit licence)
    *
    * Copyright (c) 2010 Jason Mora Saragih
    * All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   *     * The software is provided under the terms of this licence stricly for
   *       academic, non-commercial, not-for-profit purposes.
   *     * Redistributions of source code must retain the above copyright notice,
   *       this list of conditions (licence) and the following disclaimer.
   *     * Redistributions in binary form must reproduce the above copyright
   *       notice, this list of conditions (licence) and the following disclaimer
   *       in the documentation and/or other materials provided with the
   *       distribution.
   *     * The name of the author may not be used to endorse or promote products
   *       derived from this software without specific prior written permission.
   *     * As this software depends on other libraries, the user must adhere to and
   *       keep in place any licencing terms of those libraries.
   *     * Any publications arising from the use of this software, including but
   *       not limited to academic journal and conference publications, technical
   *       reports and manuals, must cite the following work:
   *
   *       J. M. Saragih, S. Lucey, and J. F. Cohn. Face Alignment through Subspace
   *       Constrained Mean-Shifts. International Journal of Computer Vision
   *       (ICCV), September, 2009.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
   * EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
   * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  package com.jsaragih;
  
  import java.io.BufferedReader;
  import java.io.BufferedWriter;
  import java.io.FileNotFoundException;
  import java.io.FileReader;
  import java.io.FileWriter;
  import java.io.IOException;
  import java.util.Scanner;
  
  import org.openimaj.image.FImage;
  
  /**
   * Multiple patches
   * 
   * @author Jason Mora Saragih
   * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
   */
  public class MPatch {
  	static { Tracker.init(); }
  	
  	/** Width of patch */
  	public int _w;
  
  	/** Height of patch */
  	public int _h;
  
  	/** List of patches */
  	public Patch[] _p;
  
  	private FImage res_;
  
  	MPatch(Patch[] p) {
  		_w = p[0].matcher.getTemplate().width;
  		_h = p[0].matcher.getTemplate().height;
  
  		for (int i = 1; i < p.length; i++) {
  			if ((p[i].matcher.getTemplate().width != _w)
  					|| (p[i].matcher.getTemplate().height != _h)) {
  				throw new IllegalArgumentException(
  						"Patches must all have the same size");
  			}
  		}
  
  		_p = p;
  		res_ = new FImage(0, 0);
  	}
  
  	MPatch() {
  	}
  
  	static MPatch load(final String fname) throws FileNotFoundException {
  		BufferedReader br = null;
  		try {
  			br = new BufferedReader(new FileReader(fname));
  			Scanner sc = new Scanner(br);
  			return read(sc, true);
 		} finally {
 			try {
 				br.close();
 			} catch (IOException e) {
 			}
 		}
 	}
 
 	void save(final String fname) throws IOException {
 		BufferedWriter bw = null;
 		try {
 			bw = new BufferedWriter(new FileWriter(fname));
 
 			write(bw);
 		} finally {
 			try {
 				if (bw != null)
 					bw.close();
 			} catch (IOException e) {
 			}
 		}
 	}
 
 	void write(BufferedWriter s) throws IOException {
 		s.write(IO.Types.MPATCH.ordinal() + " " + _w + " " + _h + " "
 				+ _p.length + " ");
 
 		for (int i = 0; i < _p.length; i++)
 			_p[i].write(s);
 	}
 
 	static MPatch read(Scanner s, boolean readType) {
 		if (readType) {
 			int type = s.nextInt();
 			assert (type == IO.Types.MPATCH.ordinal());
 		}
 
 		MPatch mpatch = new MPatch();
 
 		mpatch._w = s.nextInt();
 		mpatch._h = s.nextInt();
 		int n = s.nextInt();
 
 		mpatch._p = new Patch[n];
 		for (int i = 0; i < n; i++)
 			mpatch._p[i] = Patch.read(s, true);
 
 		return mpatch;
 	}
 
 	final void sum2one(FImage M) {
 		M.divideInplace(M.sum());
 	}
 
 	void response(FImage im, FImage resp) {
 		assert ((im.height >= _h) && (im.width >= _w));
 
 		int h = im.height - _h + 1, w = im.width - _w + 1;
 
 		if (resp.height != h || resp.width != w)
 			resp.internalAssign(new FImage(w, h));
 
 		if (res_ == null)
 			res_ = new FImage(w, h);
 		if (res_.height != h || res_.width != w)
 			res_.internalAssign(new FImage(w, h));
 
 		if (_p.length == 1) {
 			_p[0].response(im, resp);
 			sum2one(resp);
 		} else {
 			resp.fill(1);
 
 			for (int i = 0; i < _p.length; i++) {
 				_p[i].response(im, res_);
 				sum2one(res_);
 				resp.multiplyInplace(res_);
 			}
 
 			sum2one(resp);
 		}
 	}
 
 	/**
 	 * Returns a copy of this MPatch
 	 * 
 	 * @return A copy of this object
 	 */
 	public MPatch copy() {
 		MPatch m = new MPatch();
 		m._w = _w;
 		m._h = _h;
 		m.res_ = res_;
 		m._p = new Patch[_p.length];
 		for (int i = 0; i < _p.length; i++)
 			m._p[i] = _p[i].copy();
 		return m;
 	}
 }