/**
 * Copyright 2010 JogAmp Community. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are
 * permitted provided that the following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright notice, this list of
 *       conditions and the following disclaimer.
 *
 *    2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``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 JogAmp Community 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.
 *
 * The views and conclusions contained in the software and documentation are those of the
 * authors and should not be interpreted as representing official policies, either expressed
 * or implied, of JogAmp Community.
 */
package com.jogamp.opengl.math.geom;

import jogamp.graph.geom.plane.AffineTransform;

import com.jogamp.opengl.math.FloatUtil;
import com.jogamp.opengl.math.Ray;
import com.jogamp.opengl.math.VectorUtil;
import com.jogamp.opengl.util.PMVMatrix;


/**
 * Axis Aligned Bounding Box. Defined by two 3D coordinates (low and high)
 * The low being the the lower left corner of the box, and the high being the upper
 * right corner of the box.
 * <p>
 * A few references for collision detection, intersections:
 * <pre>
 * http://www.realtimerendering.com/intersections.html
 * http://www.codercorner.com/RayAABB.cpp
 * http://www.siggraph.org/education/materials/HyperGraph/raytrace/rtinter0.htm
 * http://realtimecollisiondetection.net/files/levine_swept_sat.txt
 * </pre>
 * </p>
 *
 */
public class AABBox implements Cloneable {
    private static final boolean DEBUG = FloatUtil.DEBUG;
    private final float[] low = new float[3];
    private final float[] high = new float[3];
    private final float[] center = new float[3];

    /** Create a Axis Aligned bounding box (AABBox)
     * where the low and and high MAX float Values.
     */
    public AABBox() {
        reset();
    }

    /** Create an AABBox specifying the coordinates
     * of the low and high
     * @param lx min x-coordinate
     * @param ly min y-coordnate
     * @param lz min z-coordinate
     * @param hx max x-coordinate
     * @param hy max y-coordinate
     * @param hz max z-coordinate
     */
    public AABBox(final float lx, final float ly, final float lz,
                  final float hx, final float hy, final float hz) {
        setSize(lx, ly, lz, hx, hy, hz);
    }

    /** Create a AABBox defining the low and high
     * @param low min xyz-coordinates
     * @param high max xyz-coordinates
     */
    public AABBox(final float[] low, final float[] high) {
        setSize(low[0],low[1],low[2], high[0],high[1],high[2]);
    }

    /** resets this box to the inverse low/high, allowing the next {@link #resize(float, float, float)} command to hit. */
    public final void reset() {
        setLow(Float.MAX_VALUE,Float.MAX_VALUE,Float.MAX_VALUE);
        setHigh(-1*Float.MAX_VALUE,-1*Float.MAX_VALUE,-1*Float.MAX_VALUE);
        center[0] = 0f;
        center[1] = 0f;
        center[2] = 0f;
    }

    /** Get the max xyz-coordinates
     * @return a float array containing the max xyz coordinates
     */
    public final float[] getHigh() {
        return high;
    }

    private final void setHigh(final float hx, final float hy, final float hz) {
        this.high[0] = hx;
        this.high[1] = hy;
        this.high[2] = hz;
    }

    /** Get the min xyz-coordinates
     * @return a float array containing the min xyz coordinates
     */
    public final float[] getLow() {
        return low;
    }

    private final void setLow(final float lx, final float ly, final float lz) {
        this.low[0] = lx;
        this.low[1] = ly;
        this.low[2] = lz;
    }

    private final void computeCenter() {
        center[0] = (high[0] + low[0])/2;
        center[1] = (high[1] + low[1])/2;
        center[2] = (high[2] + low[2])/2;
    }

    /**
     * Set size of the AABBox specifying the coordinates
     * of the low and high.
     *
     * @param lx min x-coordinate
     * @param ly min y-coordnate
     * @param lz min z-coordinate
     * @param hx max x-coordinate
     * @param hy max y-coordinate
     * @param hz max z-coordinate
     */
    public final void setSize(final float lx, final float ly, final float lz,
                              final float hx, final float hy, final float hz) {
        this.low[0] = lx;
        this.low[1] = ly;
        this.low[2] = lz;
        this.high[0] = hx;
        this.high[1] = hy;
        this.high[2] = hz;
        computeCenter();
    }

    /** Resize the AABBox to encapsulate another AABox
     * @param newBox AABBox to be encapsulated in
     */
    public final void resize(final AABBox newBox) {
        float[] newLow = newBox.getLow();
        float[] newHigh = newBox.getHigh();

        /** test low */
        if (newLow[0] < low[0])
            low[0] = newLow[0];
        if (newLow[1] < low[1])
            low[1] = newLow[1];
        if (newLow[2] < low[2])
            low[2] = newLow[2];

        /** test high */
        if (newHigh[0] > high[0])
            high[0] = newHigh[0];
        if (newHigh[1] > high[1])
            high[1] = newHigh[1];
        if (newHigh[2] > high[2])
            high[2] = newHigh[2];

        computeCenter();
    }

    public final void resize(final AABBox newBox, final AffineTransform t, final float[] tmpV3) {
        /** test low */
        {
            final float[] newBoxLow = newBox.getLow();
            t.transform(newBoxLow, tmpV3);
            tmpV3[2] = newBoxLow[2];
            if (tmpV3[0] < low[0])
                low[0] = tmpV3[0];
            if (tmpV3[1] < low[1])
                low[1] = tmpV3[1];
            if (tmpV3[2] < low[2])
                low[2] = tmpV3[2];
        }

        /** test high */
        {
            final float[] newBoxHigh = newBox.getHigh();
            t.transform(newBoxHigh, tmpV3);
            tmpV3[2] = newBoxHigh[2];
            if (tmpV3[0] > high[0])
                high[0] = tmpV3[0];
            if (tmpV3[1] > high[1])
                high[1] = tmpV3[1];
            if (tmpV3[2] > high[2])
                high[2] = tmpV3[2];
        }

        computeCenter();
    }

    /** Resize the AABBox to encapsulate the passed
     * xyz-coordinates.
     * @param x x-axis coordinate value
     * @param y y-axis coordinate value
     * @param z z-axis coordinate value
     */
    public final void resize(final float x, final float y, final float z) {
        /** test low */
        if (x < low[0]) {
            low[0] = x;
        }
        if (y < low[1]) {
            low[1] = y;
        }
        if (z < low[2]) {
            low[2] = z;
        }

        /** test high */
        if (x > high[0]) {
            high[0] = x;
        }
        if (y > high[1]) {
            high[1] = y;
        }
        if (z > high[2]) {
            high[2] = z;
        }

        computeCenter();
    }

    /**
     * Resize the AABBox to encapsulate the passed
     * xyz-coordinates.
     * @param xyz xyz-axis coordinate values
     * @param offset of the array
     */
    public final void resize(final float[] xyz, final int offset) {
        resize(xyz[0+offset], xyz[1+offset], xyz[2+offset]);
    }

    /**
     * Resize the AABBox to encapsulate the passed
     * xyz-coordinates.
     * @param xyz xyz-axis coordinate values
     */
    public final void resize(final float[] xyz) {
        resize(xyz[0], xyz[1], xyz[2]);
    }

    /**
     * Check if the x & y coordinates are bounded/contained
     * by this AABBox
     * @param x  x-axis coordinate value
     * @param y  y-axis coordinate value
     * @return true if  x belong to (low.x, high.x) and
     * y belong to (low.y, high.y)
     */
    public final boolean contains(final float x, final float y) {
        if(x<low[0] || x>high[0]){
            return false;
        }
        if(y<low[1]|| y>high[1]){
            return false;
        }
        return true;
    }

    /**
     * Check if the xyz coordinates are bounded/contained
     * by this AABBox.
     * @param x x-axis coordinate value
     * @param y y-axis coordinate value
     * @param z z-axis coordinate value
     * @return true if  x belong to (low.x, high.x) and
     * y belong to (low.y, high.y) and  z belong to (low.z, high.z)
     */
    public final boolean contains(final float x, final float y, final float z) {
        if(x<low[0] || x>high[0]){
            return false;
        }
        if(y<low[1]|| y>high[1]){
            return false;
        }
        if(z<low[2] || z>high[2]){
            return false;
        }
        return true;
    }

    /**
     * Check if there is a common region between this AABBox and the passed
     * 2D region irrespective of z range
     * @param x lower left x-coord
     * @param y lower left y-coord
     * @param w width
     * @param h hight
     * @return true if this AABBox might have a common region with this 2D region
     */
    public final boolean intersects2DRegion(final float x, final float y, final float w, final float h) {
        if (w <= 0 || h <= 0) {
            return false;
        }

        final float _w = getWidth();
        final float _h = getHeight();
        if (_w <= 0 || _h <= 0) {
            return false;
        }

        final float x0 = getMinX();
        final float y0 = getMinY();
        return (x + w > x0 &&
                y + h > y0 &&
                x < x0 + _w &&
                y < y0 + _h);
    }

    /**
     * Check if {@link Ray} intersects this bounding box.
     * <p>
     * Versions uses the SAT[1], testing 6 axes.
     * Original code for OBBs from MAGIC.
     * Rewritten for AABBs and reorganized for early exits[2].
     * </p>
     * <pre>
     * [1] SAT = Separating Axis Theorem
     * [2] http://www.codercorner.com/RayAABB.cpp
     * </pre>
     * @param ray
     * @return
     */
    public final boolean intersectsRay(final Ray ray) {
        // diff[XYZ] -> VectorUtil.subVec3(diff, ray.orig, center);
        //  ext[XYZ] -> extend VectorUtil.subVec3(ext, high, center);

        final float dirX  = ray.dir[0];
        final float diffX = ray.orig[0] - center[0];
        final float extX  = high[0] - center[0];
        if( Math.abs(diffX) > extX && diffX*dirX >= 0f ) return false;

        final float dirY  = ray.dir[1];
        final float diffY = ray.orig[1] - center[1];
        final float extY  = high[1] - center[1];
        if( Math.abs(diffY) > extY && diffY*dirY >= 0f ) return false;

        final float dirZ  = ray.dir[2];
        final float diffZ = ray.orig[2] - center[2];
        final float extZ  = high[2] - center[2];
        if( Math.abs(diffZ) > extZ && diffZ*dirZ >= 0f ) return false;

        final float absDirY = Math.abs(dirY);
        final float absDirZ = Math.abs(dirZ);

        float f = dirY * diffZ - dirZ * diffY;
        if( Math.abs(f) > extY*absDirZ + extZ*absDirY ) return false;

        final float absDirX = Math.abs(dirX);

        f = dirZ * diffX - dirX * diffZ;
        if( Math.abs(f) > extX*absDirZ + extZ*absDirX ) return false;

        f = dirX * diffY - dirY * diffX;
        if( Math.abs(f) > extX*absDirY + extY*absDirX ) return false;

        return true;
    }


    /** Get the size of the Box where the size is represented by the
     * length of the vector between low and high.
     * @return a float representing the size of the AABBox
     */
    public final float getSize() {
        return VectorUtil.vec3Distance(low, high);
    }

    /**Get the Center of the AABBox
     * @return the xyz-coordinates of the center of the AABBox
     */
    public final float[] getCenter() {
        return center;
    }

    /**
     * Scale the AABBox by a constant
     * @param size a constant float value
     * @param tmpV3 caller provided temporary 3-component vector
     */
    public final void scale(final float size, final float[] tmpV3) {
        tmpV3[0] = high[0] - center[0];
        tmpV3[1] = high[1] - center[1];
        tmpV3[2] = high[2] - center[2];

        VectorUtil.scaleVec3(tmpV3, tmpV3, size); // in-place scale
        VectorUtil.addVec3(high, center, tmpV3);

        tmpV3[0] = low[0] - center[0];
        tmpV3[1] = low[1] - center[1];
        tmpV3[2] = low[2] - center[2];

        VectorUtil.scaleVec3(tmpV3, tmpV3, size); // in-place scale
        VectorUtil.addVec3(low, center, tmpV3);
    }

    public final float getMinX() {
        return low[0];
    }

    public final float getMinY() {
        return low[1];
    }

    public final float getMinZ() {
        return low[2];
    }

    public final float getMaxX() {
        return high[0];
    }

    public final float getMaxY() {
        return high[1];
    }

    public final float getMaxZ() {
        return high[2];
    }

    public final float getWidth(){
        return high[0] - low[0];
    }

    public final float getHeight() {
        return high[1] - low[1];
    }

    public final float getDepth() {
        return high[2] - low[2];
    }

    @Override
    public final AABBox clone() {
        return new AABBox(this.low, this.high);
    }

    @Override
    public final boolean equals(Object obj) {
        if( obj == this ) {
            return true;
        }
        if( null == obj || !(obj instanceof AABBox) ) {
            return false;
        }
        final AABBox other = (AABBox) obj;
        return VectorUtil.isVec2Equal(low, 0, other.low, 0, FloatUtil.EPSILON) &&
               VectorUtil.isVec3Equal(high, 0, other.high, 0, FloatUtil.EPSILON) ;
    }

    /**
     * Assume this bounding box as being in object space and
     * compute the window bounding box.
     * <p>
     * If <code>useCenterZ</code> is <code>true</code>,
     * only 4 {@link PMVMatrix#gluProject(float, float, float, int[], int, float[], int) gluProject}
     * operations are made on points [1..4] using {@link #getCenter()}'s z-value.
     * Otherwise 8 {@link PMVMatrix#gluProject(float, float, float, int[], int, float[], int) gluProject}
     * operation on all 8 points are performed.
     * </p>
     * <pre>
     *  [2] ------ [4]
     *   |          |
     *   |          |
     *  [1] ------ [3]
     * </pre>
     * @param pmv
     * @param view
     * @param useCenterZ
     * @param tmpV3 TODO
     * @return
     */
    public AABBox mapToWindow(final AABBox result, final PMVMatrix pmv, final int[] view, final boolean useCenterZ, float[] tmpV3) {
        // System.err.printf("AABBox.mapToWindow.0: view[%d, %d, %d, %d], this %s%n", view[0], view[1], view[2], view[3], toString());
        float objZ = useCenterZ ? center[2] : getMinZ();
        pmv.gluProject(getMinX(), getMinY(), objZ, view, 0, tmpV3, 0);
        // System.err.printf("AABBox.mapToWindow.p1: %f, %f, %f -> %f, %f, %f%n", getMinX(), getMinY(), objZ, tmpV3[0], tmpV3[1], tmpV3[2]);
        // System.err.printf("AABBox.mapToWindow.p1: %s%n", pmv.toString());
        result.reset();
        result.resize(tmpV3, 0);
        pmv.gluProject(getMinX(), getMaxY(), objZ, view, 0, tmpV3, 0);
        // System.err.printf("AABBox.mapToWindow.p2: %f, %f, %f -> %f, %f, %f%n", getMinX(), getMaxY(), objZ, tmpV3[0], tmpV3[1], tmpV3[2]);
        result.resize(tmpV3, 0);
        pmv.gluProject(getMaxX(), getMinY(), objZ, view, 0, tmpV3, 0);
        // System.err.printf("AABBox.mapToWindow.p3: %f, %f, %f -> %f, %f, %f%n", getMaxX(), getMinY(), objZ, tmpV3[0], tmpV3[1], tmpV3[2]);
        result.resize(tmpV3, 0);
        pmv.gluProject(getMaxX(), getMaxY(), objZ, view, 0, tmpV3, 0);
        // System.err.printf("AABBox.mapToWindow.p4: %f, %f, %f -> %f, %f, %f%n", getMaxX(), getMaxY(), objZ, tmpV3[0], tmpV3[1], tmpV3[2]);
        result.resize(tmpV3, 0);
        if( !useCenterZ ) {
            objZ = getMaxZ();
            pmv.gluProject(getMinX(), getMinY(), objZ, view, 0, tmpV3, 0);
            result.resize(tmpV3, 0);
            pmv.gluProject(getMinX(), getMaxY(), objZ, view, 0, tmpV3, 0);
            result.resize(tmpV3, 0);
            pmv.gluProject(getMaxX(), getMinY(), objZ, view, 0, tmpV3, 0);
            result.resize(tmpV3, 0);
            pmv.gluProject(getMaxX(), getMaxY(), objZ, view, 0, tmpV3, 0);
            result.resize(tmpV3, 0);
        }
        if( DEBUG ) {
            System.err.printf("AABBox.mapToWindow: view[%d, %d], this %s -> %s%n", view[0], view[1], toString(), result.toString());
        }
        return result;
    }

    @Override
    public final String toString() {
        return "[ dim "+getWidth()+" x "+getHeight()+" x "+getDepth()+
               ", box "+low[0]+" / "+low[1]+" / "+low[2]+" .. "+high[0]+" / "+high[1]+" / "+high[2]+
               ", ctr "+center[0]+" / "+center[1]+" / "+center[2]+" ]";
    }
}