/*

 * Copyright 1998-2006 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package javax.swing.text.html;

import java.awt.Polygon;

import java.io.Serializable;

import java.util.StringTokenizer;

import java.util.Vector;

import javax.swing.text.AttributeSet;

/**

 * Map is used to represent a map element that is part of an HTML document.

 * Once a Map has been created, and any number of areas have been added,

 * you can test if a point falls inside the map via the contains method.

 *

 * @author  Scott Violet

 */

class Map implements Serializable {

    /** Name of the Map. */

    private String           name;

    /** An array of AttributeSets. */

    private Vector           areaAttributes;

    /** An array of RegionContainments, will slowly grow to match the

     * length of areaAttributes as needed. */

    private Vector           areas;

    public Map() {

    }

    public Map(String name) {

        this.name = name;

    }

    /**

     * Returns the name of the Map.

     */

    public String getName() {

        return name;

    }

    /**

     * Defines a region of the Map, based on the passed in AttributeSet.

     */

    public void addArea(AttributeSet as) {

        if (as == null) {

            return;

        }

        if (areaAttributes == null) {

            areaAttributes = new Vector(2);

        }

        areaAttributes.addElement(as.copyAttributes());

    }

    /**

     * Removes the previously created area.

     */

    public void removeArea(AttributeSet as) {

        if (as != null && areaAttributes != null) {

            int numAreas = (areas != null) ? areas.size() : 0;

            for (int counter = areaAttributes.size() - 1; counter >= 0;

                 counter--) {

                if (((AttributeSet)areaAttributes.elementAt(counter)).

                    isEqual(as)){

                    areaAttributes.removeElementAt(counter);

                    if (counter < numAreas) {

                        areas.removeElementAt(counter);

                    }

                }

            }

        }

    }

    /**

     * Returns the AttributeSets representing the differet areas of the Map.

     */

    public AttributeSet[] getAreas() {

        int numAttributes = (areaAttributes != null) ? areaAttributes.size() :

                            0;

        if (numAttributes != 0) {

            AttributeSet[]    retValue = new AttributeSet[numAttributes];

            areaAttributes.copyInto(retValue);

            return retValue;

        }

        return null;

    }

    /**

     * Returns the AttributeSet that contains the passed in location,

     * <code>x</code>, <code>y</code>. <code>width</code>, <code>height</code>

     * gives the size of the region the map is defined over. If a matching

     * area is found, the AttribueSet for it is returned.

     */

    public AttributeSet getArea(int x, int y, int width, int height) {

        int      numAttributes = (areaAttributes != null) ?

                                 areaAttributes.size() : 0;

        if (numAttributes > 0) {

            int      numAreas = (areas != null) ? areas.size() : 0;

            if (areas == null) {

                areas = new Vector(numAttributes);

            }

            for (int counter = 0; counter < numAttributes; counter++) {

                if (counter >= numAreas) {

                    areas.addElement(createRegionContainment

                            ((AttributeSet)areaAttributes.elementAt(counter)));

                }

                RegionContainment       rc = (RegionContainment)areas.

                                             elementAt(counter);

                if (rc != null && rc.contains(x, y, width, height)) {

                    return (AttributeSet)areaAttributes.elementAt(counter);

                }

            }

        }

        return null;

    }

    /**

     * Creates and returns an instance of RegionContainment that can be

     * used to test if a particular point lies inside a region.

     */

    protected RegionContainment createRegionContainment

                                  (AttributeSet attributes) {

        Object     shape = attributes.getAttribute(HTML.Attribute.SHAPE);

        if (shape == null) {

            shape = "rect";

        }

        if (shape instanceof String) {

            String                shapeString = ((String)shape).toLowerCase();

            RegionContainment     rc = null;

            try {

                if (shapeString.equals("rect")) {

                    rc = new RectangleRegionContainment(attributes);

                }

                else if (shapeString.equals("circle")) {

                    rc = new CircleRegionContainment(attributes);

                }

                else if (shapeString.equals("poly")) {

                    rc = new PolygonRegionContainment(attributes);

                }

                else if (shapeString.equals("default")) {

                    rc = DefaultRegionContainment.sharedInstance();

                }

            } catch (RuntimeException re) {

                // Something wrong with attributes.

                rc = null;

            }

            return rc;

        }

        return null;

    }

    /**

     * Creates and returns an array of integers from the String

     * <code>stringCoords</code>. If one of the values represents a

     * % the returned value with be negative. If a parse error results

     * from trying to parse one of the numbers null is returned.

     */

    static protected int[] extractCoords(Object stringCoords) {

        if (stringCoords == null || !(stringCoords instanceof String)) {

            return null;

        }

        StringTokenizer    st = new StringTokenizer((String)stringCoords,

                                                    ", \t\n\r");

        int[]              retValue = null;

        int                numCoords = 0;

        while(st.hasMoreElements()) {

            String         token = st.nextToken();

            int            scale;

            if (token.endsWith("%")) {

                scale = -1;

                token = token.substring(0, token.length() - 1);

            }

            else {

                scale = 1;

            }

            try {

                int       intValue = Integer.parseInt(token);

                if (retValue == null) {

                    retValue = new int[4];

                }

                else if(numCoords == retValue.length) {

                    int[]    temp = new int[retValue.length * 2];

                    System.arraycopy(retValue, 0, temp, 0, retValue.length);

                    retValue = temp;

                }

                retValue[numCoords++] = intValue * scale;

            } catch (NumberFormatException nfe) {

                return null;

            }

        }

        if (numCoords > 0 && numCoords != retValue.length) {

            int[]    temp = new int[numCoords];

            System.arraycopy(retValue, 0, temp, 0, numCoords);

            retValue = temp;

        }

        return retValue;

    }

    /**

     * Defines the interface used for to check if a point is inside a

     * region.

     */

    interface RegionContainment {

        /**

         * Returns true if the location <code>x</code>, <code>y</code>

         * falls inside the region defined in the receiver.

         * <code>width</code>, <code>height</code> is the size of

         * the enclosing region.

         */

        public boolean contains(int x, int y, int width, int height);

    }

    /**

     * Used to test for containment in a rectangular region.

     */

    static class RectangleRegionContainment implements RegionContainment {

        /** Will be non-null if one of the values is a percent, and any value

         * that is non null indicates it is a percent

         * (order is x, y, width, height). */

        float[]       percents;

        /** Last value of width passed in. */

        int           lastWidth;

        /** Last value of height passed in. */

        int           lastHeight;

        /** Top left. */

        int           x0;

        int           y0;

        /** Bottom right. */

        int           x1;

        int           y1;

        public RectangleRegionContainment(AttributeSet as) {

            int[]    coords = Map.extractCoords(as.getAttribute(HTML.

                                                           Attribute.COORDS));

            percents = null;

            if (coords == null || coords.length != 4) {

                throw new RuntimeException("Unable to parse rectangular area");

            }

            else {

                x0 = coords[0];

                y0 = coords[1];

                x1 = coords[2];

                y1 = coords[3];

                if (x0 < 0 || y0 < 0 || x1 < 0 || y1 < 0) {

                    percents = new float[4];

                    lastWidth = lastHeight = -1;

                    for (int counter = 0; counter < 4; counter++) {

                        if (coords[counter] < 0) {

                            percents[counter] = Math.abs

                                        (coords[counter]) / 100.0f;

                        }

                        else {

                            percents[counter] = -1.0f;

                        }

                    }

                }

            }

        }

        public boolean contains(int x, int y, int width, int height) {

            if (percents == null) {

                return contains(x, y);

            }

            if (lastWidth != width || lastHeight != height) {

                lastWidth = width;

                lastHeight = height;

                if (percents[0] != -1.0f) {

                    x0 = (int)(percents[0] * width);

                }

                if (percents[1] != -1.0f) {

                    y0 = (int)(percents[1] * height);

                }

                if (percents[2] != -1.0f) {

                    x1 = (int)(percents[2] * width);

                }

                if (percents[3] != -1.0f) {

                    y1 = (int)(percents[3] * height);

                }

            }

            return contains(x, y);

        }

        public boolean contains(int x, int y) {

            return ((x >= x0 && x <= x1) &&

                    (y >= y0 && y <= y1));

        }

    }

    /**

     * Used to test for containment in a polygon region.

     */

    static class PolygonRegionContainment extends Polygon implements

                 RegionContainment {

        /** If any value is a percent there will be an entry here for the

         * percent value. Use percentIndex to find out the index for it. */

        float[]           percentValues;

        int[]             percentIndexs;

        /** Last value of width passed in. */

        int               lastWidth;

        /** Last value of height passed in. */

        int               lastHeight;

        public PolygonRegionContainment(AttributeSet as) {

            int[]    coords = Map.extractCoords(as.getAttribute(HTML.Attribute.

                                                                COORDS));

            if (coords == null || coords.length == 0 ||

                coords.length % 2 != 0) {

                throw new RuntimeException("Unable to parse polygon area");

            }

            else {

                int        numPercents = 0;

                lastWidth = lastHeight = -1;

                for (int counter = coords.length - 1; counter >= 0;

                     counter--) {

                    if (coords[counter] < 0) {

                        numPercents++;

                    }

                }

                if (numPercents > 0) {

                    percentIndexs = new int[numPercents];

                    percentValues = new float[numPercents];

                    for (int counter = coords.length - 1, pCounter = 0;

                         counter >= 0; counter--) {

                        if (coords[counter] < 0) {

                            percentValues[pCounter] = coords[counter] /

                                                      -100.0f;

                            percentIndexs[pCounter] = counter;

                            pCounter++;

                        }

                    }

                }

                else {

                    percentIndexs = null;

                    percentValues = null;

                }

                npoints = coords.length / 2;

                xpoints = new int[npoints];

                ypoints = new int[npoints];

                for (int counter = 0; counter < npoints; counter++) {

                    xpoints[counter] = coords[counter + counter];

                    ypoints[counter] = coords[counter + counter + 1];

                }

            }

        }

        public boolean contains(int x, int y, int width, int height) {

            if (percentValues == null || (lastWidth == width &&

                                          lastHeight == height)) {

                return contains(x, y);

            }

            // Force the bounding box to be recalced.

            bounds = null;

            lastWidth = width;

            lastHeight = height;

            float fWidth = (float)width;

            float fHeight = (float)height;

            for (int counter = percentValues.length - 1; counter >= 0;

                 counter--) {

                if (percentIndexs[counter] % 2 == 0) {

                    // x

                    xpoints[percentIndexs[counter] / 2] =

                            (int)(percentValues[counter] * fWidth);

                }

                else {

                    // y

                    ypoints[percentIndexs[counter] / 2] =

                            (int)(percentValues[counter] * fHeight);

                }

            }

            return contains(x, y);

        }

    }

    /**

     * Used to test for containment in a circular region.

     */

    static class CircleRegionContainment implements RegionContainment {

        /** X origin of the circle. */

        int           x;

        /** Y origin of the circle. */

        int           y;

        /** Radius of the circle. */

        int           radiusSquared;

        /** Non-null indicates one of the values represents a percent. */

        float[]       percentValues;

        /** Last value of width passed in. */

        int           lastWidth;

        /** Last value of height passed in. */

        int           lastHeight;

        public CircleRegionContainment(AttributeSet as) {

            int[]    coords = Map.extractCoords(as.getAttribute(HTML.Attribute.

                                                                COORDS));

            if (coords == null || coords.length != 3) {

                throw new RuntimeException("Unable to parse circular area");

            }

            x = coords[0];

            y = coords[1];

            radiusSquared = coords[2] * coords[2];

            if (coords[0] < 0 || coords[1] < 0 || coords[2] < 0) {

                lastWidth = lastHeight = -1;

                percentValues = new float[3];

                for (int counter = 0; counter < 3; counter++) {

                    if (coords[counter] < 0) {

                        percentValues[counter] = coords[counter] /

                                                 -100.0f;

                    }

                    else {

                        percentValues[counter] = -1.0f;

                    }

                }

            }

            else {

                percentValues = null;

            }

        }

        public boolean contains(int x, int y, int width, int height) {

            if (percentValues != null && (lastWidth != width ||

                                          lastHeight != height)) {

                int      newRad = Math.min(width, height) / 2;

                lastWidth = width;

                lastHeight = height;

                if (percentValues[0] != -1.0f) {

                    this.x = (int)(percentValues[0] * width);

                }

                if (percentValues[1] != -1.0f) {

                    this.y = (int)(percentValues[1] * height);

                }

                if (percentValues[2] != -1.0f) {

                    radiusSquared = (int)(percentValues[2] *

                                   Math.min(width, height));

                    radiusSquared *= radiusSquared;

                }

            }

            return (((x - this.x) * (x - this.x) +

                     (y - this.y) * (y - this.y)) <= radiusSquared);

        }

    }

    /**

     * An implementation that will return true if the x, y location is

     * inside a rectangle defined by origin 0, 0, and width equal to

     * width passed in, and height equal to height passed in.

     */

    static class DefaultRegionContainment implements RegionContainment {

        /** A global shared instance. */

        static DefaultRegionContainment  si = null;

        public static DefaultRegionContainment sharedInstance() {

            if (si == null) {

                si = new DefaultRegionContainment();

            }

            return si;

        }

        public boolean contains(int x, int y, int width, int height) {

            return (x <= width && x >= 0 && y >= 0 && y <= width);

        }

    }

}