/**
 * Copyright (c) 2011, The University of Southampton and the individual contributors.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *   *  Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *   *  Redistributions in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the documentation
 *      and/or other materials provided with the distribution.
 *
 *   *  Neither the name of the University of Southampton nor the names of its
 *      contributors may be used to endorse or promote products derived from this
 *      software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 OWNER 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 org.openimaj.image.contour;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.openimaj.image.pixel.Pixel;
import org.openimaj.math.geometry.shape.Polygon;
import org.openimaj.math.geometry.shape.Rectangle;

/**
 * A contour or hierarchical set of contours within an image.
 * 
 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
 */
public class Contour extends Polygon {
        /**
         * The type of contour
         */
        public ContourType type;
        /**
         * sub contours
         */
        public List<Contour> children = new ArrayList<Contour>();
        /**
         * The parent contour, might be null
         */
        public Contour parent;

        /**
         * where the contour starts
         */
        public Pixel start;
        Rectangle rect = null;

        /**
         * Construct a contour with the given type and start at the origin
         * 
         * @param type
         *            the type
         */
        public Contour(ContourType type) {
                this.type = type;
                this.start = new Pixel(0, 0);
        }

        /**
         * Construct a contour with the given type and start pixel
         * 
         * @param type
         *            the type
         * @param x
         *            the x-ordinate of the start pixel
         * @param y
         *            the y-ordinate of the start pixel
         */
        public Contour(ContourType type, int x, int y) {
                this.type = type;
                this.start = new Pixel(x, y);
        }

        /**
         * Construct a contour with the given type and start pixel
         * 
         * @param type
         *            the type
         * @param p
         *            the coordinate of the start pixel
         */
        public Contour(ContourType type, Pixel p) {
                this.type = type;
                this.start = p;
        }

        /**
         * Construct a contour with the given starting coordinate and a
         * <code>null</code> type.
         * 
         * @param x
         *            the x-ordinate of the start pixel
         * @param y
         *            the y-ordinate of the start pixel
         */
        public Contour(int x, int y) {
                this.type = null;
                this.start = new Pixel(x, y);
        }

        protected void setParent(Contour bp) {
                this.parent = bp;
                bp.children.add(this);
        }

        @Override
        public String toString() {
                final StringWriter contour = new StringWriter();
                final PrintWriter pw = new PrintWriter(contour);
                pw.println(String.format("[%s] start: %s %s", this.type, this.start, this.points));
                for (final Contour child : this.children) {
                        pw.print(child);
                }
                pw.flush();
                return contour.toString();
        }

        /**
         * Complete this contour by computing it's bounding box
         */
        public void finish() {
                this.rect = this.calculateRegularBoundingBox();
        }

        private class ContourIterator implements Iterator<Contour> {
                final List<Contour> toProcess = new ArrayList<Contour>();

                ContourIterator() {
                        toProcess.add(Contour.this);
                }

                @Override
                public boolean hasNext() {
                        return !toProcess.isEmpty();
                }

                @Override
                public Contour next() {
                        final Contour next = toProcess.remove(toProcess.size() - 1);
                        toProcess.addAll(next.children);
                        return next;
                }

                @Override
                public void remove() {
                        throw new UnsupportedOperationException("Removal not supported");
                }
        }

        /**
         * Get an iterator over the complete set of contours (including the root
         * itself)
         * 
         * @return the iterator
         */
        public Iterator<Contour> contourIterator() {
                return new ContourIterator();
        }

        /**
         * Get an {@link Iterable} over all the contours belonging to this root
         * (including the root itself)
         * 
         * @return the iterable
         */
        public Iterable<Contour> contourIterable() {
                return new Iterable<Contour>() {
                        @Override
                        public Iterator<Contour> iterator() {
                                return contourIterator();
                        }
                };
        }

        @Override
        public boolean isHole() {
                return type != null && type.equals(ContourType.HOLE);
        }
}