/* -*- 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 <sal/config.h>

#include <tools/gen.hxx>
#include <vcl/outdev.hxx>
#include <vcl/alpha.hxx>
#include <vcl/virdev.hxx>
#include <vcl/GraphicObject.hxx>
#include <memory>

struct ImplTileInfo
{
    ImplTileInfo() : nTilesEmptyX(0), nTilesEmptyY(0) {}

    Point aTileTopLeft;     // top, left position of the rendered tile
    Point aNextTileTopLeft; // top, left position for next recursion
                            // level's tile
    Size  aTileSizePixel;   // size of the generated tile (might
                            // differ from
                            // aNextTileTopLeft-aTileTopLeft, because
                            // this is nExponent*prevTileSize. The
                            // generated tile is always nExponent
                            // times the previous tile, such that it
                            // can be used in the next stage. The
                            // required area coverage is often
                            // less. The extraneous area covered is
                            // later overwritten by the next stage)
    int   nTilesEmptyX;     // number of original tiles empty right of
                            // this tile. This counts from
                            // aNextTileTopLeft, i.e. the additional
                            // area covered by aTileSizePixel is not
                            // considered here. This is for
                            // unification purposes, as the iterative
                            // calculation of the next level's empty
                            // tiles has to be based on this value.
    int   nTilesEmptyY;     // as above, for Y
};


bool GraphicObject::ImplRenderTempTile( VirtualDevice& rVDev,
                                        int nNumTilesX, int nNumTilesY,
                                        const Size& rTileSizePixel,
                                        const GraphicAttr* pAttr )
{
    // how many tiles to generate per recursion step
    const int nExponent = 2;

    // determine MSB factor
    int nMSBFactor( 1 );
    while( nNumTilesX / nMSBFactor != 0 ||
           nNumTilesY / nMSBFactor != 0 )
    {
        nMSBFactor *= nExponent;
    }

    // one less
    if(nMSBFactor > 1)
    {
        nMSBFactor /= nExponent;
    }
    ImplTileInfo aTileInfo;

    // #105229# Switch off mapping (converting to logic and back to
    // pixel might cause roundoff errors)
    bool bOldMap( rVDev.IsMapModeEnabled() );
    rVDev.EnableMapMode( false );

    bool bRet( ImplRenderTileRecursive( rVDev, nExponent, nMSBFactor, nNumTilesX, nNumTilesY,
                                        nNumTilesX, nNumTilesY, rTileSizePixel, pAttr, aTileInfo ) );

    rVDev.EnableMapMode( bOldMap );

    return bRet;
}

// define for debug drawings
//#define DBG_TEST

// see header comment. this works similar to base conversion of a
// number, i.e. if the exponent is 10, then the number for every tile
// size is given by the decimal place of the corresponding decimal
// representation.
bool GraphicObject::ImplRenderTileRecursive( VirtualDevice& rVDev, int nExponent, int nMSBFactor,
                                             int nNumOrigTilesX, int nNumOrigTilesY,
                                             int nRemainderTilesX, int nRemainderTilesY,
                                             const Size& rTileSizePixel, const GraphicAttr* pAttr,
                                             ImplTileInfo& rTileInfo )
{
    // gets loaded with our tile bitmap
    std::unique_ptr<GraphicObject> xTmpGraphic;
    GraphicObject* pTileGraphic;

    // stores a flag that renders the zero'th tile position
    // (i.e. (0,0)+rCurrPos) only if we're at the bottom of the
    // recursion stack. All other position already have that tile
    // rendered, because the lower levels painted their generated tile
    // there.
    bool bNoFirstTileDraw( false );

    // what's left when we're done with our tile size
    const int nNewRemainderX( nRemainderTilesX % nMSBFactor );
    const int nNewRemainderY( nRemainderTilesY % nMSBFactor );

    // gets filled out from the recursive call with info of what's
    // been generated
    ImplTileInfo aTileInfo;

    // check for recursion's end condition: LSB place reached?
    if( nMSBFactor == 1 )
    {
        pTileGraphic = this;

        // set initial tile size -> orig size
        aTileInfo.aTileSizePixel = rTileSizePixel;
        aTileInfo.nTilesEmptyX = nNumOrigTilesX;
        aTileInfo.nTilesEmptyY = nNumOrigTilesY;
    }
    else if( ImplRenderTileRecursive( rVDev, nExponent, nMSBFactor/nExponent,
                                      nNumOrigTilesX, nNumOrigTilesY,
                                      nNewRemainderX, nNewRemainderY,
                                      rTileSizePixel, pAttr, aTileInfo ) )
    {
        // extract generated tile -> see comment on the first loop below
        BitmapEx aTileBitmap( rVDev.GetBitmap( aTileInfo.aTileTopLeft, aTileInfo.aTileSizePixel ) );

        xTmpGraphic.reset(new GraphicObject(std::move(aTileBitmap)));
        pTileGraphic = xTmpGraphic.get();

        // fill stripes left over from upstream levels:

        //  x0000
        //  0
        //  0
        //  0
        //  0

        // where x denotes the place filled by our recursive predecessors

        // check whether we have to fill stripes here. Although not
        // obvious, there is one case where we can skip this step: if
        // the previous recursion level (the one who filled our
        // aTileInfo) had zero area to fill, then there are no white
        // stripes left, naturally. This happens if the digit
        // associated to that level has a zero, and can be checked via
        // aTileTopLeft==aNextTileTopLeft.
        if( aTileInfo.aTileTopLeft != aTileInfo.aNextTileTopLeft )
        {
            // now fill one row from aTileInfo.aNextTileTopLeft.X() all
            // the way to the right
            // current output position while drawing
            Point aCurrPos(aTileInfo.aNextTileTopLeft.X(), aTileInfo.aTileTopLeft.Y());
            for (int nX=0; nX < aTileInfo.nTilesEmptyX; nX += nMSBFactor)
            {
                if (!pTileGraphic->Draw(rVDev, aCurrPos, aTileInfo.aTileSizePixel, pAttr))
                    return false;

                aCurrPos.AdjustX(aTileInfo.aTileSizePixel.Width() );
            }

#ifdef DBG_TEST
//          rVDev.SetFillCOL_WHITE );
            rVDev.SetFillColor();
            rVDev.SetLineColor( Color( 255 * nExponent / nMSBFactor, 255 - 255 * nExponent / nMSBFactor, 128 - 255 * nExponent / nMSBFactor ) );
            rVDev.DrawEllipse( tools::Rectangle(aTileInfo.aNextTileTopLeft.X(), aTileInfo.aTileTopLeft.Y(),
                                         aTileInfo.aNextTileTopLeft.X() - 1 + (aTileInfo.nTilesEmptyX/nMSBFactor)*aTileInfo.aTileSizePixel.Width(),
                                         aTileInfo.aTileTopLeft.Y() + aTileInfo.aTileSizePixel.Height() - 1) );
#endif

            // now fill one column from aTileInfo.aNextTileTopLeft.Y() all
            // the way to the bottom
            aCurrPos.setX( aTileInfo.aTileTopLeft.X() );
            aCurrPos.setY( aTileInfo.aNextTileTopLeft.Y() );
            for (int nY=0; nY < aTileInfo.nTilesEmptyY; nY += nMSBFactor)
            {
                if (!pTileGraphic->Draw(rVDev, aCurrPos, aTileInfo.aTileSizePixel, pAttr))
                    return false;

                aCurrPos.AdjustY(aTileInfo.aTileSizePixel.Height() );
            }

#ifdef DBG_TEST
            rVDev.DrawEllipse( tools::Rectangle(aTileInfo.aTileTopLeft.X(), aTileInfo.aNextTileTopLeft.Y(),
                                         aTileInfo.aTileTopLeft.X() + aTileInfo.aTileSizePixel.Width() - 1,
                                         aTileInfo.aNextTileTopLeft.Y() - 1 + (aTileInfo.nTilesEmptyY/nMSBFactor)*aTileInfo.aTileSizePixel.Height()) );
#endif
        }
        else
        {
            // Thought that aTileInfo.aNextTileTopLeft tile has always
            // been drawn already, but that's wrong: typically,
            // _parts_ of that tile have been drawn, since the
            // previous level generated the tile there. But when
            // aTileInfo.aNextTileTopLeft!=aTileInfo.aTileTopLeft, the
            // difference between these two values is missing in the
            // lower right corner of this first tile. So, can do that
            // only here.
            bNoFirstTileDraw = true;
        }
    }
    else
    {
        return false;
    }

    // calc number of original tiles in our drawing area without
    // remainder
    nRemainderTilesX -= nNewRemainderX;
    nRemainderTilesY -= nNewRemainderY;

    // fill tile info for calling method
    rTileInfo.aTileTopLeft     = aTileInfo.aNextTileTopLeft;
    rTileInfo.aNextTileTopLeft = Point( rTileInfo.aTileTopLeft.X() + rTileSizePixel.Width()*nRemainderTilesX,
                                        rTileInfo.aTileTopLeft.Y() + rTileSizePixel.Height()*nRemainderTilesY );
    rTileInfo.aTileSizePixel   = Size( rTileSizePixel.Width()*nMSBFactor*nExponent,
                                       rTileSizePixel.Height()*nMSBFactor*nExponent );
    rTileInfo.nTilesEmptyX     = aTileInfo.nTilesEmptyX - nRemainderTilesX;
    rTileInfo.nTilesEmptyY     = aTileInfo.nTilesEmptyY - nRemainderTilesY;

    // init output position
    Point aCurrPos = aTileInfo.aNextTileTopLeft;

    // fill our drawing area. Fill possibly more, to create the next
    // bigger tile size -> see bitmap extraction above. This does no
    // harm, since everything right or below our actual area is
    // overdrawn by our caller. Just in case we're in the last level,
    // we don't draw beyond the right or bottom border.
    for (int nY=0; nY < aTileInfo.nTilesEmptyY && nY < nExponent*nMSBFactor; nY += nMSBFactor)
    {
        aCurrPos.setX( aTileInfo.aNextTileTopLeft.X() );

        for (int nX=0; nX < aTileInfo.nTilesEmptyX && nX < nExponent*nMSBFactor; nX += nMSBFactor)
        {
            if( bNoFirstTileDraw )
                bNoFirstTileDraw = false; // don't draw first tile position
            else if (!pTileGraphic->Draw(rVDev, aCurrPos, aTileInfo.aTileSizePixel, pAttr))
                return false;

            aCurrPos.AdjustX(aTileInfo.aTileSizePixel.Width() );
        }

        aCurrPos.AdjustY(aTileInfo.aTileSizePixel.Height() );
    }

#ifdef DBG_TEST
//  rVDev.SetFillCOL_WHITE );
    rVDev.SetFillColor();
    rVDev.SetLineColor( Color( 255 * nExponent / nMSBFactor, 255 - 255 * nExponent / nMSBFactor, 128 - 255 * nExponent / nMSBFactor ) );
    rVDev.DrawRect( tools::Rectangle((rTileInfo.aTileTopLeft.X())*rTileSizePixel.Width(),
                              (rTileInfo.aTileTopLeft.Y())*rTileSizePixel.Height(),
                              (rTileInfo.aNextTileTopLeft.X())*rTileSizePixel.Width()-1,
                              (rTileInfo.aNextTileTopLeft.Y())*rTileSizePixel.Height()-1) );
#endif

    return true;
}

bool GraphicObject::ImplDrawTiled(OutputDevice& rOut, const tools::Rectangle& rArea, const Size& rSizePixel,
                                  const Size& rOffset, const GraphicAttr* pAttr, int nTileCacheSize1D)
{
    const MapMode   aOutMapMode(rOut.GetMapMode());
    const MapMode   aMapMode( aOutMapMode.GetMapUnit(), Point(), aOutMapMode.GetScaleX(), aOutMapMode.GetScaleY() );
    bool            bRet( false );

    // #i42643# Casting to Int64, to avoid integer overflow for
    // huge-DPI output devices
    if( GetGraphic().GetType() == GraphicType::Bitmap &&
        static_cast<sal_Int64>(rSizePixel.Width()) * rSizePixel.Height() <
        static_cast<sal_Int64>(nTileCacheSize1D)*nTileCacheSize1D )
    {
        // First combine very small bitmaps into a larger tile


        ScopedVclPtrInstance< VirtualDevice > aVDev;
        const int       nNumTilesInCacheX( (nTileCacheSize1D + rSizePixel.Width()-1) / rSizePixel.Width() );
        const int       nNumTilesInCacheY( (nTileCacheSize1D + rSizePixel.Height()-1) / rSizePixel.Height() );

        aVDev->SetOutputSizePixel( Size( nNumTilesInCacheX*rSizePixel.Width(),
                                        nNumTilesInCacheY*rSizePixel.Height() ) );
        aVDev->SetMapMode( aMapMode );

        // draw bitmap content
        if( ImplRenderTempTile( *aVDev, nNumTilesInCacheX,
                                nNumTilesInCacheY, rSizePixel, pAttr ) )
        {
            BitmapEx aTileBitmap( aVDev->GetBitmap( Point(0,0), aVDev->GetOutputSize() ) );

            // draw alpha content, if any
            if( IsTransparent() )
            {
                GraphicObject aAlphaGraphic;

                if( GetGraphic().IsAlpha() )
                    aAlphaGraphic.SetGraphic(BitmapEx(GetGraphic().GetBitmapEx().GetAlphaMask().GetBitmap()));
                else
                    aAlphaGraphic.SetGraphic(BitmapEx(Bitmap()));

                if( aAlphaGraphic.ImplRenderTempTile( *aVDev, nNumTilesInCacheX,
                                                      nNumTilesInCacheY, rSizePixel, pAttr ) )
                {
                    // Combine bitmap and alpha/mask
                    if( GetGraphic().IsAlpha() )
                        aTileBitmap = BitmapEx( aTileBitmap.GetBitmap(),
                                                AlphaMask( aVDev->GetBitmap( Point(0,0), aVDev->GetOutputSize() ) ) );
                    else
                        aTileBitmap = BitmapEx( aTileBitmap.GetBitmap(),
                                                aVDev->GetBitmap( Point(0,0), aVDev->GetOutputSize() ).CreateAlphaMask( COL_WHITE ) );
                }
            }

            // paint generated tile
            GraphicObject aTmpGraphic( aTileBitmap );
            bRet = aTmpGraphic.ImplDrawTiled(rOut, rArea,
                                             aTileBitmap.GetSizePixel(),
                                             rOffset, pAttr, nTileCacheSize1D);
        }
    }
    else
    {
        const Size      aOutOffset( rOut.LogicToPixel( rOffset, aOutMapMode ) );
        const tools::Rectangle aOutArea( rOut.LogicToPixel( rArea, aOutMapMode ) );

        // number of invisible (because out-of-area) tiles
        int nInvisibleTilesX;
        int nInvisibleTilesY;

        // round towards -infty for negative offset
        if( aOutOffset.Width() < 0 )
            nInvisibleTilesX = (aOutOffset.Width() - rSizePixel.Width() + 1) / rSizePixel.Width();
        else
            nInvisibleTilesX = aOutOffset.Width() / rSizePixel.Width();

        // round towards -infty for negative offset
        if( aOutOffset.Height() < 0 )
            nInvisibleTilesY = (aOutOffset.Height() - rSizePixel.Height() + 1) / rSizePixel.Height();
        else
            nInvisibleTilesY = aOutOffset.Height() / rSizePixel.Height();

        // origin from where to 'virtually' start drawing in pixel
        const Point aOutOrigin( rOut.LogicToPixel( Point( rArea.Left() - rOffset.Width(),
                                                           rArea.Top() - rOffset.Height() ) ) );
        // position in pixel from where to really start output
        const Point aOutStart( aOutOrigin.X() + nInvisibleTilesX*rSizePixel.Width(),
                               aOutOrigin.Y() + nInvisibleTilesY*rSizePixel.Height() );

        rOut.Push( vcl::PushFlags::CLIPREGION );
        rOut.IntersectClipRegion( rArea );

        // Paint all tiles
        auto nOutAreaWidth = aOutArea.GetWidth();
        auto nOutAreaHeight = aOutArea.GetHeight();
        assert(nOutAreaWidth >= 0 && nOutAreaHeight >= 0 && "coverity 2023.12.2");
        bRet = ImplDrawTiled(rOut, aOutStart,
                             (nOutAreaWidth + aOutArea.Left() - aOutStart.X() + rSizePixel.Width() - 1) / rSizePixel.Width(),
                             (nOutAreaHeight + aOutArea.Top() - aOutStart.Y() + rSizePixel.Height() - 1) / rSizePixel.Height(),
                             rSizePixel, pAttr);

        rOut.Pop();
    }

    return bRet;
}

bool GraphicObject::ImplDrawTiled( OutputDevice& rOut, const Point& rPosPixel,
                                   int nNumTilesX, int nNumTilesY,
                                   const Size& rTileSizePixel, const GraphicAttr* pAttr ) const
{
    Point   aCurrPos( rPosPixel );
    Size    aTileSizeLogic( rOut.PixelToLogic( rTileSizePixel ) );
    int     nX, nY;

    // #107607# Use logical coordinates for metafile playing, too
    bool    bDrawInPixel( rOut.GetConnectMetaFile() == nullptr && GraphicType::Bitmap == GetType() );
    bool    bRet = false;

    // #105229# Switch off mapping (converting to logic and back to
    // pixel might cause roundoff errors)
    bool bOldMap( rOut.IsMapModeEnabled() );

    if( bDrawInPixel )
        rOut.EnableMapMode( false );

    for( nY=0; nY < nNumTilesY; ++nY )
    {
        aCurrPos.setX( rPosPixel.X() );

        for( nX=0; nX < nNumTilesX; ++nX )
        {
            // #105229# work with pixel coordinates here, mapping is disabled!
            // #104004# don't disable mapping for metafile recordings
            // #108412# don't quit the loop if one draw fails

            // update return value. This method should return true, if
            // at least one of the looped Draws succeeded.
            bRet |= Draw(rOut,
                         bDrawInPixel ? aCurrPos : rOut.PixelToLogic(aCurrPos),
                         bDrawInPixel ? rTileSizePixel : aTileSizeLogic,
                         pAttr);

            aCurrPos.AdjustX(rTileSizePixel.Width() );
        }

        aCurrPos.AdjustY(rTileSizePixel.Height() );
    }

    if( bDrawInPixel )
        rOut.EnableMapMode( bOldMap );

    return bRet;
}

void GraphicObject::ImplTransformBitmap( BitmapEx&          rBmpEx,
                                         const GraphicAttr& rAttr,
                                         const Size&        rCropLeftTop,
                                         const Size&        rCropRightBottom,
                                         const tools::Rectangle&   rCropRect,
                                         const Size&        rDstSize,
                                         bool               bEnlarge ) const
{
    // #107947# Extracted from svdograf.cxx

    // #104115# Crop the bitmap
    if( rAttr.IsCropped() )
    {
        rBmpEx.Crop( rCropRect );

        // #104115# Negative crop sizes mean: enlarge bitmap and pad
        if( bEnlarge && (
            rCropLeftTop.Width() < 0 ||
            rCropLeftTop.Height() < 0 ||
            rCropRightBottom.Width() < 0 ||
            rCropRightBottom.Height() < 0 ) )
        {
            Size aBmpSize( rBmpEx.GetSizePixel() );
            sal_Int32 nPadLeft( rCropLeftTop.Width() < 0 ? -rCropLeftTop.Width() : 0 );
            sal_Int32 nPadTop( rCropLeftTop.Height() < 0 ? -rCropLeftTop.Height() : 0 );
            sal_Int32 nPadTotalWidth( aBmpSize.Width() + nPadLeft + (rCropRightBottom.Width() < 0 ? -rCropRightBottom.Width() : 0) );
            sal_Int32 nPadTotalHeight( aBmpSize.Height() + nPadTop + (rCropRightBottom.Height() < 0 ? -rCropRightBottom.Height() : 0) );

            BitmapEx aBmpEx2;

            if( rBmpEx.IsAlpha() )
            {
                aBmpEx2 = rBmpEx;
            }
            else
            {
                // #104115# Generate mask bitmap and init to zero
                AlphaMask aMask(aBmpSize);
                aMask.Erase(255);

                // #104115# Always generate transparent bitmap, we need the border transparent
                aBmpEx2 = BitmapEx( rBmpEx.GetBitmap(), aMask );

                // #104115# Add opaque mask to source bitmap, otherwise the destination remains transparent
                rBmpEx = aBmpEx2;
            }

            aBmpEx2.Scale(Size(nPadTotalWidth, nPadTotalHeight));
            aBmpEx2.Erase( Color(ColorAlpha,0,0,0,0) );
            aBmpEx2.CopyPixel( tools::Rectangle( Point(nPadLeft, nPadTop), aBmpSize ), tools::Rectangle( Point(0, 0), aBmpSize ), rBmpEx );
            rBmpEx = aBmpEx2;
        }
    }

    const Size  aSizePixel( rBmpEx.GetSizePixel() );

    if( rAttr.GetRotation() == 0_deg10 || IsAnimated() )
        return;

    if( !(aSizePixel.Width() && aSizePixel.Height() && rDstSize.Width() && rDstSize.Height()) )
        return;

    double fSrcWH = static_cast<double>(aSizePixel.Width()) / aSizePixel.Height();
    double fDstWH = static_cast<double>(rDstSize.Width()) / rDstSize.Height();
    double fScaleX = 1.0, fScaleY = 1.0;

    // always choose scaling to shrink bitmap
    if( fSrcWH < fDstWH )
        fScaleY = aSizePixel.Width() / ( fDstWH * aSizePixel.Height() );
    else
        fScaleX = fDstWH * aSizePixel.Height() / aSizePixel.Width();

    rBmpEx.Scale( fScaleX, fScaleY );
}

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