/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you under the Apache
 *   License, Version 2.0 (the "License"); you may not use this file
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */

#include <drawinglayer/primitive2d/gridprimitive2d.hxx>
#include <basegfx/utils/canvastools.hxx>
#include <drawinglayer/primitive2d/pointarrayprimitive2d.hxx>
#include <drawinglayer/primitive2d/markerarrayprimitive2d.hxx>
#include <drawinglayer/geometry/viewinformation2d.hxx>
#include <drawinglayer/primitive2d/drawinglayer_primitivetypes2d.hxx>
#include <basegfx/matrix/b2dhommatrixtools.hxx>


using namespace com::sun::star;


namespace drawinglayer
{
    namespace primitive2d
    {
        void GridPrimitive2D::create2DDecomposition(Primitive2DContainer& rContainer, const geometry::ViewInformation2D& rViewInformation) const
        {
            if(!rViewInformation.getViewport().isEmpty() && getWidth() > 0.0 && getHeight() > 0.0)
            {
                // decompose grid matrix to get logic size
                basegfx::B2DVector aScale, aTranslate;
                double fRotate, fShearX;
                getTransform().decompose(aScale, aTranslate, fRotate, fShearX);

                // create grid matrix which transforms from scaled logic to view
                basegfx::B2DHomMatrix aRST(basegfx::utils::createShearXRotateTranslateB2DHomMatrix(
                    fShearX, fRotate, aTranslate.getX(), aTranslate.getY()));
                aRST *= rViewInformation.getObjectToViewTransformation();

                // get step widths
                double fStepX(getWidth());
                double fStepY(getHeight());
                const double fMinimalStep(10.0);

                // guarantee a step width of 10.0
                if(basegfx::fTools::less(fStepX, fMinimalStep))
                {
                    fStepX = fMinimalStep;
                }

                if(basegfx::fTools::less(fStepY, fMinimalStep))
                {
                    fStepY = fMinimalStep;
                }

                // get relative distances in view coordinates
                double fViewStepX((rViewInformation.getObjectToViewTransformation() * basegfx::B2DVector(fStepX, 0.0)).getLength());
                double fViewStepY((rViewInformation.getObjectToViewTransformation() * basegfx::B2DVector(0.0, fStepY)).getLength());
                double fSmallStepX(1.0), fViewSmallStepX(1.0), fSmallStepY(1.0), fViewSmallStepY(1.0);
                sal_uInt32 nSmallStepsX(0), nSmallStepsY(0);

                // setup subdivisions
                if(getSubdivisionsX())
                {
                    fSmallStepX = fStepX / getSubdivisionsX();
                    fViewSmallStepX = fViewStepX / getSubdivisionsX();
                }

                if(getSubdivisionsY())
                {
                    fSmallStepY = fStepY / getSubdivisionsY();
                    fViewSmallStepY = fViewStepY / getSubdivisionsY();
                }

                // correct step width
                while(fViewStepX < getSmallestViewDistance())
                {
                    fViewStepX *= 2.0;
                    fStepX *= 2.0;
                }

                while(fViewStepY < getSmallestViewDistance())
                {
                    fViewStepY *= 2.0;
                    fStepY *= 2.0;
                }

                // correct small step width
                if(getSubdivisionsX())
                {
                    while(fViewSmallStepX < getSmallestSubdivisionViewDistance())
                    {
                        fViewSmallStepX *= 2.0;
                        fSmallStepX *= 2.0;
                    }

                    nSmallStepsX = static_cast<sal_uInt32>(fStepX / fSmallStepX);
                }

                if(getSubdivisionsY())
                {
                    while(fViewSmallStepY < getSmallestSubdivisionViewDistance())
                    {
                        fViewSmallStepY *= 2.0;
                        fSmallStepY *= 2.0;
                    }

                    nSmallStepsY = static_cast<sal_uInt32>(fStepY / fSmallStepY);
                }

                // calculate extended viewport in which grid points may lie at all
                basegfx::B2DRange aExtendedViewport;

                if(rViewInformation.getDiscreteViewport().isEmpty())
                {
                    // not set, use logic size to travel over all potential grid points
                    aExtendedViewport = basegfx::B2DRange(0.0, 0.0, aScale.getX(), aScale.getY());
                }
                else
                {
                    // transform unit range to discrete view
                    aExtendedViewport = basegfx::B2DRange(0.0, 0.0, 1.0, 1.0);
                    basegfx::B2DHomMatrix aTrans(rViewInformation.getObjectToViewTransformation() * getTransform());
                    aExtendedViewport.transform(aTrans);

                    // intersect with visible part
                    aExtendedViewport.intersect(rViewInformation.getDiscreteViewport());

                    if(!aExtendedViewport.isEmpty())
                    {
                        // convert back and apply scale
                        aTrans.invert();
                        aTrans.scale(aScale.getX(), aScale.getY());
                        aExtendedViewport.transform(aTrans);

                        // crop start/end in X/Y to multiples of logical step width
                        const double fHalfCrossSize((rViewInformation.getInverseObjectToViewTransformation() * basegfx::B2DVector(3.0, 0.0)).getLength());
                        const double fMinX(floor((aExtendedViewport.getMinX() - fHalfCrossSize) / fStepX) * fStepX);
                        const double fMaxX(ceil((aExtendedViewport.getMaxX() + fHalfCrossSize) / fStepX) * fStepX);
                        const double fMinY(floor((aExtendedViewport.getMinY() - fHalfCrossSize) / fStepY) * fStepY);
                        const double fMaxY(ceil((aExtendedViewport.getMaxY() + fHalfCrossSize) / fStepY) * fStepY);

                        // put to aExtendedViewport and crop on object logic size
                        aExtendedViewport = basegfx::B2DRange(
                            std::max(fMinX, 0.0),
                            std::max(fMinY, 0.0),
                            std::min(fMaxX, aScale.getX()),
                            std::min(fMaxY, aScale.getY()));
                    }
                }

                if(!aExtendedViewport.isEmpty())
                {
                    // prepare point vectors for point and cross markers
                    std::vector< basegfx::B2DPoint > aPositionsPoint;
                    std::vector< basegfx::B2DPoint > aPositionsCross;

                    for(double fX(aExtendedViewport.getMinX()); fX < aExtendedViewport.getMaxX(); fX += fStepX)
                    {
                        const bool bXZero(basegfx::fTools::equalZero(fX));

                        for(double fY(aExtendedViewport.getMinY()); fY < aExtendedViewport.getMaxY(); fY += fStepY)
                        {
                            const bool bYZero(basegfx::fTools::equalZero(fY));

                            if(!bXZero && !bYZero)
                            {
                                // get discrete position and test against 3x3 area surrounding it
                                // since it's a cross
                                const double fHalfCrossSize(3.0 * 0.5);
                                const basegfx::B2DPoint aViewPos(aRST * basegfx::B2DPoint(fX, fY));
                                const basegfx::B2DRange aDiscreteRangeCross(
                                    aViewPos.getX() - fHalfCrossSize, aViewPos.getY() - fHalfCrossSize,
                                    aViewPos.getX() + fHalfCrossSize, aViewPos.getY() + fHalfCrossSize);

                                if(rViewInformation.getDiscreteViewport().overlaps(aDiscreteRangeCross))
                                {
                                    const basegfx::B2DPoint aLogicPos(rViewInformation.getInverseObjectToViewTransformation() * aViewPos);
                                    aPositionsCross.push_back(aLogicPos);
                                }
                            }

                            if(getSubdivisionsX() && !bYZero)
                            {
                                double fF(fX + fSmallStepX);

                                for(sal_uInt32 a(1); a < nSmallStepsX && fF < aExtendedViewport.getMaxX(); a++, fF += fSmallStepX)
                                {
                                    const basegfx::B2DPoint aViewPos(aRST * basegfx::B2DPoint(fF, fY));

                                    if(rViewInformation.getDiscreteViewport().isInside(aViewPos))
                                    {
                                        const basegfx::B2DPoint aLogicPos(rViewInformation.getInverseObjectToViewTransformation() * aViewPos);
                                        aPositionsPoint.push_back(aLogicPos);
                                    }
                                }
                            }

                            if(getSubdivisionsY() && !bXZero)
                            {
                                double fF(fY + fSmallStepY);

                                for(sal_uInt32 a(1); a < nSmallStepsY && fF < aExtendedViewport.getMaxY(); a++, fF += fSmallStepY)
                                {
                                    const basegfx::B2DPoint aViewPos(aRST * basegfx::B2DPoint(fX, fF));

                                    if(rViewInformation.getDiscreteViewport().isInside(aViewPos))
                                    {
                                        const basegfx::B2DPoint aLogicPos(rViewInformation.getInverseObjectToViewTransformation() * aViewPos);
                                        aPositionsPoint.push_back(aLogicPos);
                                    }
                                }
                            }
                        }
                    }

                    // prepare return value
                    const sal_uInt32 nCountPoint(aPositionsPoint.size());
                    const sal_uInt32 nCountCross(aPositionsCross.size());

                    // add PointArrayPrimitive2D if point markers were added
                    if(nCountPoint)
                    {
                        rContainer.push_back(new PointArrayPrimitive2D(aPositionsPoint, getBColor()));
                    }

                    // add MarkerArrayPrimitive2D if cross markers were added
                    if(nCountCross)
                    {
                        if(!getSubdivisionsX() && !getSubdivisionsY())
                        {
                            // no subdivisions, so fall back to points at grid positions, no need to
                            // visualize a difference between divisions and sub-divisions
                            rContainer.push_back(new PointArrayPrimitive2D(aPositionsCross, getBColor()));
                        }
                        else
                        {
                            rContainer.push_back(new MarkerArrayPrimitive2D(aPositionsCross, getCrossMarker()));
                        }
                    }
                }
            }
        }

        GridPrimitive2D::GridPrimitive2D(
            const basegfx::B2DHomMatrix& rTransform,
            double fWidth,
            double fHeight,
            double fSmallestViewDistance,
            double fSmallestSubdivisionViewDistance,
            sal_uInt32 nSubdivisionsX,
            sal_uInt32 nSubdivisionsY,
            const basegfx::BColor& rBColor,
            const BitmapEx& rCrossMarker)
        :   BufferedDecompositionPrimitive2D(),
            maTransform(rTransform),
            mfWidth(fWidth),
            mfHeight(fHeight),
            mfSmallestViewDistance(fSmallestViewDistance),
            mfSmallestSubdivisionViewDistance(fSmallestSubdivisionViewDistance),
            mnSubdivisionsX(nSubdivisionsX),
            mnSubdivisionsY(nSubdivisionsY),
            maBColor(rBColor),
            maCrossMarker(rCrossMarker),
            maLastObjectToViewTransformation(),
            maLastViewport()
        {
        }

        bool GridPrimitive2D::operator==(const BasePrimitive2D& rPrimitive) const
        {
            if(BufferedDecompositionPrimitive2D::operator==(rPrimitive))
            {
                const GridPrimitive2D& rCompare = static_cast<const GridPrimitive2D&>(rPrimitive);

                return (getTransform() == rCompare.getTransform()
                    && getWidth() == rCompare.getWidth()
                    && getHeight() == rCompare.getHeight()
                    && getSmallestViewDistance() == rCompare.getSmallestViewDistance()
                    && getSmallestSubdivisionViewDistance() == rCompare.getSmallestSubdivisionViewDistance()
                    && getSubdivisionsX() == rCompare.getSubdivisionsX()
                    && getSubdivisionsY() == rCompare.getSubdivisionsY()
                    && getBColor() == rCompare.getBColor()
                    && getCrossMarker() == rCompare.getCrossMarker());
            }

            return false;
        }

        basegfx::B2DRange GridPrimitive2D::getB2DRange(const geometry::ViewInformation2D& rViewInformation) const
        {
            // get object's range
            basegfx::B2DRange aUnitRange(0.0, 0.0, 1.0, 1.0);
            aUnitRange.transform(getTransform());

            // intersect with visible part
            aUnitRange.intersect(rViewInformation.getViewport());

            return aUnitRange;
        }

        void GridPrimitive2D::get2DDecomposition(Primitive2DDecompositionVisitor& rVisitor, const geometry::ViewInformation2D& rViewInformation) const
        {
            ::osl::MutexGuard aGuard( m_aMutex );

            if(!getBuffered2DDecomposition().empty())
            {
                if(maLastViewport != rViewInformation.getViewport() || maLastObjectToViewTransformation != rViewInformation.getObjectToViewTransformation())
                {
                    // conditions of last local decomposition have changed, delete
                    const_cast< GridPrimitive2D* >(this)->setBuffered2DDecomposition(Primitive2DContainer());
                }
            }

            if(getBuffered2DDecomposition().empty())
            {
                // remember ViewRange and ViewTransformation
                const_cast< GridPrimitive2D* >(this)->maLastObjectToViewTransformation = rViewInformation.getObjectToViewTransformation();
                const_cast< GridPrimitive2D* >(this)->maLastViewport = rViewInformation.getViewport();
            }

            // use parent implementation
            BufferedDecompositionPrimitive2D::get2DDecomposition(rVisitor, rViewInformation);
        }

        // provide unique ID
        ImplPrimitive2DIDBlock(GridPrimitive2D, PRIMITIVE2D_ID_GRIDPRIMITIVE2D)

    } // end of namespace primitive2d
} // end of namespace drawinglayer

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */