/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
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 *
 * 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/diagnose_ex.h>
#include <tools/long.hxx>
#include <basegfx/matrix/b2dhommatrix.hxx>
#include <basegfx/numeric/ftools.hxx>
#include <basegfx/utils/canvastools.hxx>
#include <com/sun/star/rendering/CompositeOperation.hpp>
#include <com/sun/star/rendering/RenderState.hpp>
#include <com/sun/star/rendering/TextDirection.hpp>
#include <com/sun/star/rendering/ViewState.hpp>
#include <comphelper/sequence.hxx>
#include <cppuhelper/supportsservice.hxx>
#include <vcl/metric.hxx>
#include <vcl/virdev.hxx>

#include <canvas/canvastools.hxx>

#include "textlayout.hxx"

#include <memory>

using namespace ::com::sun::star;

namespace vclcanvas
{
    namespace
    {
        void setupLayoutMode( OutputDevice& rOutDev,
                              sal_Int8      nTextDirection )
        {
            // TODO(P3): avoid if already correctly set
            ComplexTextLayoutFlags nLayoutMode = ComplexTextLayoutFlags::Default;
            switch( nTextDirection )
            {
                case rendering::TextDirection::WEAK_LEFT_TO_RIGHT:
                    break;
                case rendering::TextDirection::STRONG_LEFT_TO_RIGHT:
                    nLayoutMode = ComplexTextLayoutFlags::BiDiStrong;
                    break;
                case rendering::TextDirection::WEAK_RIGHT_TO_LEFT:
                    nLayoutMode = ComplexTextLayoutFlags::BiDiRtl;
                    break;
                case rendering::TextDirection::STRONG_RIGHT_TO_LEFT:
                    nLayoutMode = ComplexTextLayoutFlags::BiDiRtl | ComplexTextLayoutFlags::BiDiStrong;
                    break;
                default:
                    break;
            }

            // set calculated layout mode. Origin is always the left edge,
            // as required at the API spec
            rOutDev.SetLayoutMode( nLayoutMode | ComplexTextLayoutFlags::TextOriginLeft );
        }
    }

    TextLayout::TextLayout( const rendering::StringContext&                  aText,
                            sal_Int8                                         nDirection,
                            const CanvasFont::Reference&                     rFont,
                            const uno::Reference<rendering::XGraphicDevice>& xDevice,
                            const OutDevProviderSharedPtr&                   rOutDev ) :
        TextLayout_Base( m_aMutex ),
        maText( aText ),
        maLogicalAdvancements(),
        mpFont( rFont ),
        mxDevice( xDevice ),
        mpOutDevProvider( rOutDev ),
        mnTextDirection( nDirection )
    {}

    void SAL_CALL TextLayout::disposing()
    {
        SolarMutexGuard aGuard;

        mpOutDevProvider.reset();
        mxDevice.clear();
        mpFont.clear();
    }

    // XTextLayout
    uno::Sequence< uno::Reference< rendering::XPolyPolygon2D > > SAL_CALL TextLayout::queryTextShapes(  )
    {
        SolarMutexGuard aGuard;

        OutputDevice& rOutDev = mpOutDevProvider->getOutDev();
        ScopedVclPtrInstance< VirtualDevice > pVDev( rOutDev );
        pVDev->SetFont( mpFont->getVCLFont() );

        setupLayoutMode( *pVDev, mnTextDirection );

        const rendering::ViewState aViewState(
            geometry::AffineMatrix2D(1,0,0, 0,1,0),
            nullptr);

        rendering::RenderState aRenderState (
            geometry::AffineMatrix2D(1,0,0,0,1,0),
            nullptr,
            uno::Sequence<double>(4),
            rendering::CompositeOperation::SOURCE);

        std::unique_ptr< ::tools::Long []> aOffsets(new ::tools::Long[maLogicalAdvancements.getLength()]);
        setupTextOffsets(aOffsets.get(), maLogicalAdvancements, aViewState, aRenderState);

        std::vector< uno::Reference< rendering::XPolyPolygon2D> > aOutlineSequence;
        ::basegfx::B2DPolyPolygonVector aOutlines;
        if (pVDev->GetTextOutlines(
            aOutlines,
            maText.Text,
            maText.StartPosition,
            maText.StartPosition,
            maText.Length,
            0,
            aOffsets.get()))
        {
            aOutlineSequence.reserve(aOutlines.size());
            sal_Int32 nIndex (0);
            for (auto const& outline : aOutlines)
            {
                aOutlineSequence[nIndex++] = ::basegfx::unotools::xPolyPolygonFromB2DPolyPolygon(
                    mxDevice,
                    outline);
            }
        }

        return comphelper::containerToSequence(aOutlineSequence);
    }

    uno::Sequence< geometry::RealRectangle2D > SAL_CALL TextLayout::queryInkMeasures(  )
    {
        SolarMutexGuard aGuard;


        OutputDevice& rOutDev = mpOutDevProvider->getOutDev();
        ScopedVclPtrInstance< VirtualDevice > pVDev( rOutDev );
        pVDev->SetFont( mpFont->getVCLFont() );

        setupLayoutMode( *pVDev, mnTextDirection );

        const rendering::ViewState aViewState(
            geometry::AffineMatrix2D(1,0,0, 0,1,0),
            nullptr);

        rendering::RenderState aRenderState (
            geometry::AffineMatrix2D(1,0,0,0,1,0),
            nullptr,
            uno::Sequence<double>(4),
            rendering::CompositeOperation::SOURCE);

        std::unique_ptr< ::tools::Long []> aOffsets(new ::tools::Long[maLogicalAdvancements.getLength()]);
        setupTextOffsets(aOffsets.get(), maLogicalAdvancements, aViewState, aRenderState);

        std::vector< ::tools::Rectangle > aMetricVector;
        uno::Sequence<geometry::RealRectangle2D> aBoundingBoxes;
        if (pVDev->GetGlyphBoundRects(
            Point(0,0),
            maText.Text,
            ::canvas::tools::numeric_cast<sal_uInt16>(maText.StartPosition),
            ::canvas::tools::numeric_cast<sal_uInt16>(maText.Length),
            aMetricVector))
        {
            aBoundingBoxes.realloc(aMetricVector.size());
            sal_Int32 nIndex (0);
            for (auto const& metric : aMetricVector)
            {
                aBoundingBoxes[nIndex++] = geometry::RealRectangle2D(
                    metric.getX(),
                    metric.getY(),
                    metric.getX() + metric.getWidth(),
                    metric.getY() + metric.getHeight());
            }
        }
        return aBoundingBoxes;
    }

    uno::Sequence< geometry::RealRectangle2D > SAL_CALL TextLayout::queryMeasures(  )
    {
        // TODO(F1)
        return uno::Sequence< geometry::RealRectangle2D >();
    }

    uno::Sequence< double > SAL_CALL TextLayout::queryLogicalAdvancements(  )
    {
        SolarMutexGuard aGuard;

        return maLogicalAdvancements;
    }

    void SAL_CALL TextLayout::applyLogicalAdvancements( const uno::Sequence< double >& aAdvancements )
    {
        SolarMutexGuard aGuard;

        ENSURE_ARG_OR_THROW( aAdvancements.getLength() == maText.Length,
                         "TextLayout::applyLogicalAdvancements(): mismatching number of advancements" );

        maLogicalAdvancements = aAdvancements;
    }

    geometry::RealRectangle2D SAL_CALL TextLayout::queryTextBounds(  )
    {
        SolarMutexGuard aGuard;

        if( !mpOutDevProvider )
            return geometry::RealRectangle2D();

        OutputDevice& rOutDev = mpOutDevProvider->getOutDev();

        ScopedVclPtrInstance< VirtualDevice > pVDev( rOutDev );
        pVDev->SetFont( mpFont->getVCLFont() );

        // need metrics for Y offset, the XCanvas always renders
        // relative to baseline
        const ::FontMetric& aMetric( pVDev->GetFontMetric() );

        setupLayoutMode( *pVDev, mnTextDirection );

        const sal_Int32 nAboveBaseline( -aMetric.GetAscent() );
        const sal_Int32 nBelowBaseline( aMetric.GetDescent() );

        if( maLogicalAdvancements.hasElements() )
        {
            return geometry::RealRectangle2D( 0, nAboveBaseline,
                                              maLogicalAdvancements[ maLogicalAdvancements.getLength()-1 ],
                                              nBelowBaseline );
        }
        else
        {
            return geometry::RealRectangle2D( 0, nAboveBaseline,
                                              pVDev->GetTextWidth(
                                                  maText.Text,
                                                  ::canvas::tools::numeric_cast<sal_uInt16>(maText.StartPosition),
                                                  ::canvas::tools::numeric_cast<sal_uInt16>(maText.Length) ),
                                              nBelowBaseline );
        }
    }

    double SAL_CALL TextLayout::justify( double )
    {
        // TODO(F1)
        return 0.0;
    }

    double SAL_CALL TextLayout::combinedJustify( const uno::Sequence< uno::Reference< rendering::XTextLayout > >&,
                                                 double )
    {
        // TODO(F1)
        return 0.0;
    }

    rendering::TextHit SAL_CALL TextLayout::getTextHit( const geometry::RealPoint2D& )
    {
        // TODO(F1)
        return rendering::TextHit();
    }

    rendering::Caret SAL_CALL TextLayout::getCaret( sal_Int32, sal_Bool )
    {
        // TODO(F1)
        return rendering::Caret();
    }

    sal_Int32 SAL_CALL TextLayout::getNextInsertionIndex( sal_Int32, sal_Int32, sal_Bool )
    {
        // TODO(F1)
        return 0;
    }

    uno::Reference< rendering::XPolyPolygon2D > SAL_CALL TextLayout::queryVisualHighlighting( sal_Int32, sal_Int32 )
    {
        // TODO(F1)
        return uno::Reference< rendering::XPolyPolygon2D >();
    }

    uno::Reference< rendering::XPolyPolygon2D > SAL_CALL TextLayout::queryLogicalHighlighting( sal_Int32, sal_Int32 )
    {
        // TODO(F1)
        return uno::Reference< rendering::XPolyPolygon2D >();
    }

    double SAL_CALL TextLayout::getBaselineOffset(  )
    {
        // TODO(F1)
        return 0.0;
    }

    sal_Int8 SAL_CALL TextLayout::getMainTextDirection(  )
    {
        SolarMutexGuard aGuard;

        return mnTextDirection;
    }

    uno::Reference< rendering::XCanvasFont > SAL_CALL TextLayout::getFont(  )
    {
        SolarMutexGuard aGuard;

        return mpFont;
    }

    rendering::StringContext SAL_CALL TextLayout::getText(  )
    {
        SolarMutexGuard aGuard;

        return maText;
    }

    void TextLayout::draw( OutputDevice&                 rOutDev,
                           const Point&                  rOutpos,
                           const rendering::ViewState&   viewState,
                           const rendering::RenderState& renderState ) const
    {
        SolarMutexGuard aGuard;

        setupLayoutMode( rOutDev, mnTextDirection );

        if( maLogicalAdvancements.hasElements() )
        {
            // TODO(P2): cache that
            std::unique_ptr< ::tools::Long []> aOffsets(new ::tools::Long[maLogicalAdvancements.getLength()]);
            setupTextOffsets( aOffsets.get(), maLogicalAdvancements, viewState, renderState );

            // TODO(F3): ensure correct length and termination for DX
            // array (last entry _must_ contain the overall width)

            rOutDev.DrawTextArray( rOutpos,
                                   maText.Text,
                                   aOffsets.get(),
                                   ::canvas::tools::numeric_cast<sal_uInt16>(maText.StartPosition),
                                   ::canvas::tools::numeric_cast<sal_uInt16>(maText.Length) );
        }
        else
        {
            rOutDev.DrawText( rOutpos,
                              maText.Text,
                              ::canvas::tools::numeric_cast<sal_uInt16>(maText.StartPosition),
                              ::canvas::tools::numeric_cast<sal_uInt16>(maText.Length) );
        }
    }

    namespace
    {
        class OffsetTransformer
        {
        public:
            explicit OffsetTransformer( const ::basegfx::B2DHomMatrix& rMat ) :
                maMatrix( rMat )
            {
            }

            sal_Int32 operator()( const double& rOffset )
            {
                // This is an optimization of the normal rMat*[x,0]
                // transformation of the advancement vector (in x
                // direction), followed by a length calculation of the
                // resulting vector: advancement' =
                // ||rMat*[x,0]||. Since advancements are vectors, we
                // can ignore translational components, thus if [x,0],
                // it follows that rMat*[x,0]=[x',0] holds. Thus, we
                // just have to calc the transformation of the x
                // component.

                // TODO(F2): Handle non-horizontal advancements!
                return ::basegfx::fround( hypot(maMatrix.get(0,0)*rOffset,
                                                maMatrix.get(1,0)*rOffset) );
            }

        private:
            ::basegfx::B2DHomMatrix maMatrix;
        };
    }

    void TextLayout::setupTextOffsets( ::tools::Long*                       outputOffsets,
                                       const uno::Sequence< double >&   inputOffsets,
                                       const rendering::ViewState&      viewState,
                                       const rendering::RenderState&    renderState     ) const
    {
        ENSURE_OR_THROW( outputOffsets!=nullptr,
                          "TextLayout::setupTextOffsets offsets NULL" );

        ::basegfx::B2DHomMatrix aMatrix;

        ::canvas::tools::mergeViewAndRenderTransform(aMatrix,
                                                     viewState,
                                                     renderState);

        // fill integer offsets
        std::transform( inputOffsets.begin(),
                          inputOffsets.end(),
                          outputOffsets,
                          OffsetTransformer( aMatrix ) );
    }

    OUString SAL_CALL TextLayout::getImplementationName()
    {
        return "VCLCanvas::TextLayout";
    }

    sal_Bool SAL_CALL TextLayout::supportsService( const OUString& ServiceName )
    {
        return cppu::supportsService( this, ServiceName );
    }

    uno::Sequence< OUString > SAL_CALL TextLayout::getSupportedServiceNames()
    {
        return { "com.sun.star.rendering.TextLayout" };
    }
}

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