/*

    Copyright (C) 2004, 2005, 2007 Nikolas Zimmermann <zimmermann@kde.org>

                  2004, 2005 Rob Buis <buis@kde.org>

                  2005 Eric Seidel <eric.seidel@kdemail.net>

    This file is part of the KDE project

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Library General Public

    License as published by the Free Software Foundation; either

    version 2 of the License, or (at your option) any later version.

    This library 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

    Library General Public License for more details.

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

    aint with this library; see the file COPYING.LIB.  If not, write to

    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

    Boston, MA 02110-1301, USA.

*/

#include "config.h"

#if ENABLE(SVG)

#include "RenderPath.h"

#include <math.h>

#include "FloatPoint.h"

#include "GraphicsContext.h"

#include "KCanvasRenderingStyle.h"

#include "PointerEventsHitRules.h"

#include "RenderSVGContainer.h"

#include "SVGPaintServer.h"

#include "SVGResourceClipper.h"

#include "SVGResourceFilter.h"

#include "SVGResourceMarker.h"

#include "SVGResourceMasker.h"

#include "SVGStyledElement.h"

#include "SVGURIReference.h"

#include <wtf/MathExtras.h>

namespace WebCore {

// RenderPath

RenderPath::RenderPath(RenderStyle* style, SVGStyledElement* node)

    : RenderObject(node)

{

    ASSERT(style != 0);

}

RenderPath::~RenderPath()

{

}

AffineTransform RenderPath::localTransform() const

{

    return m_matrix;

}

void RenderPath::setLocalTransform(const AffineTransform& matrix)

{

    m_matrix = matrix;

}

FloatPoint RenderPath::mapAbsolutePointToLocal(const FloatPoint& point) const

{

    // FIXME: does it make sense to map incoming points with the inverse of the

    // absolute transform? 

    double localX;

    double localY;

    absoluteTransform().inverse().map(point.x(), point.y(), &localX, &localY);

    return FloatPoint::narrowPrecision(localX, localY);

}

bool RenderPath::fillContains(const FloatPoint& point, bool requiresFill) const

{

    if (m_path.isEmpty())

        return false;

    if (requiresFill && !KSVGPainterFactory::fillPaintServer(style(), this))

        return false;

    return m_path.contains(point, style()->svgStyle()->fillRule());

}

FloatRect RenderPath::relativeBBox(bool includeStroke) const

{

    if (m_path.isEmpty())

        return FloatRect();

    if (includeStroke) {

        if (m_strokeBbox.isEmpty())

            m_strokeBbox = strokeBBox();

        return m_strokeBbox;

    }

    if (m_fillBBox.isEmpty())

        m_fillBBox = m_path.boundingRect();

    return m_fillBBox;

}

void RenderPath::setPath(const Path& newPath)

{

    m_path = newPath;

    m_strokeBbox = FloatRect();

    m_fillBBox = FloatRect();

}

const Path& RenderPath::path() const

{

    return m_path;

}

void RenderPath::layout()

{

    IntRect oldBounds;

    IntRect oldOutlineBox;

    bool checkForRepaint = checkForRepaintDuringLayout();

    if (selfNeedsLayout() && checkForRepaint) {

        oldBounds = m_absoluteBounds;

        oldOutlineBox = absoluteOutlineBox();

    }

    setPath(static_cast<SVGStyledElement*>(element())->toPathData());

    m_absoluteBounds = absoluteClippedOverflowRect();

    setWidth(m_absoluteBounds.width());

    setHeight(m_absoluteBounds.height());

    if (selfNeedsLayout() && checkForRepaint)

        repaintAfterLayoutIfNeeded(oldBounds, oldOutlineBox);

    setNeedsLayout(false);

}

IntRect RenderPath::absoluteClippedOverflowRect()

{

    FloatRect repaintRect = absoluteTransform().mapRect(relativeBBox(true));

    // Markers can expand the bounding box

    repaintRect.unite(m_markerBounds);

#if ENABLE(SVG_EXPERIMENTAL_FEATURES)

    // Filters can expand the bounding box

    SVGResourceFilter* filter = getFilterById(document(), SVGURIReference::getTarget(style()->svgStyle()->filter()));

    if (filter)

        repaintRect.unite(filter->filterBBoxForItemBBox(repaintRect));

#endif

    if (!repaintRect.isEmpty())

        repaintRect.inflate(1); // inflate 1 pixel for antialiasing

    return enclosingIntRect(repaintRect);

}

bool RenderPath::requiresLayer()

{

    return false;

}

short RenderPath::lineHeight(bool b, bool isRootLineBox) const

{

    return static_cast<short>(relativeBBox(true).height());

}

short RenderPath::baselinePosition(bool b, bool isRootLineBox) const

{

    return static_cast<short>(relativeBBox(true).height());

}

void RenderPath::paint(PaintInfo& paintInfo, int, int)

{

    if (paintInfo.context->paintingDisabled() || (paintInfo.phase != PaintPhaseForeground) || style()->visibility() == HIDDEN || m_path.isEmpty())

        return;

    paintInfo.context->save();

    paintInfo.context->concatCTM(localTransform());

    FloatRect strokeBBox = relativeBBox(true);

    SVGElement* svgElement = static_cast<SVGElement*>(element());

    ASSERT(svgElement && svgElement->document() && svgElement->isStyled());

    SVGStyledElement* styledElement = static_cast<SVGStyledElement*>(svgElement);

    const SVGRenderStyle* svgStyle = style()->svgStyle();

    AtomicString filterId(SVGURIReference::getTarget(svgStyle->filter()));

    AtomicString clipperId(SVGURIReference::getTarget(svgStyle->clipPath()));

    AtomicString maskerId(SVGURIReference::getTarget(svgStyle->maskElement()));

#if ENABLE(SVG_EXPERIMENTAL_FEATURES)

    SVGResourceFilter* filter = getFilterById(document(), filterId);

#endif

    SVGResourceClipper* clipper = getClipperById(document(), clipperId);

    SVGResourceMasker* masker = getMaskerById(document(), maskerId);

#if ENABLE(SVG_EXPERIMENTAL_FEATURES)

    if (filter)

        filter->prepareFilter(paintInfo.context, strokeBBox);

    else if (!filterId.isEmpty())

        svgElement->document()->accessSVGExtensions()->addPendingResource(filterId, styledElement);

#endif

    if (clipper) {

        clipper->addClient(styledElement);

        clipper->applyClip(paintInfo.context, strokeBBox);

    } else if (!clipperId.isEmpty())

        svgElement->document()->accessSVGExtensions()->addPendingResource(clipperId, styledElement);

    if (masker) {

        masker->addClient(styledElement);

        masker->applyMask(paintInfo.context, strokeBBox);

    } else if (!maskerId.isEmpty())

        svgElement->document()->accessSVGExtensions()->addPendingResource(maskerId, styledElement);

    paintInfo.context->beginPath();

    SVGPaintServer* fillPaintServer = KSVGPainterFactory::fillPaintServer(style(), this);

    if (fillPaintServer) {

        paintInfo.context->addPath(m_path);

        fillPaintServer->draw(paintInfo.context, this, ApplyToFillTargetType);

    }

    SVGPaintServer* strokePaintServer = KSVGPainterFactory::strokePaintServer(style(), this);

    if (strokePaintServer) {

        paintInfo.context->addPath(m_path); // path is cleared when filled.

        strokePaintServer->draw(paintInfo.context, this, ApplyToStrokeTargetType);

    }

    if (styledElement->supportsMarkers())

        m_markerBounds = drawMarkersIfNeeded(paintInfo.context, paintInfo.rect, m_path);

#if ENABLE(SVG_EXPERIMENTAL_FEATURES)

    // actually apply the filter

    if (filter)

        filter->applyFilter(paintInfo.context, strokeBBox);

#endif

    paintInfo.context->restore();

}

void RenderPath::absoluteRects(Vector<IntRect>& rects, int _tx, int _ty, bool)

{

    rects.append(absoluteClippedOverflowRect());

}

bool RenderPath::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, int _x, int _y, int _tx, int _ty, HitTestAction hitTestAction)

{

    // We only draw in the forground phase, so we only hit-test then.

    if (hitTestAction != HitTestForeground)

        return false;

    PointerEventsHitRules hitRules(PointerEventsHitRules::SVG_PATH_HITTESTING, style()->svgStyle()->pointerEvents());

    bool isVisible = (style()->visibility() == VISIBLE);

    if (isVisible || !hitRules.requireVisible) {

        FloatPoint hitPoint = mapAbsolutePointToLocal(FloatPoint(_x, _y));

        if ((hitRules.canHitStroke && (style()->svgStyle()->hasStroke() || !hitRules.requireStroke) && strokeContains(hitPoint, hitRules.requireStroke))

            || (hitRules.canHitFill && (style()->svgStyle()->hasFill() || !hitRules.requireFill) && fillContains(hitPoint, hitRules.requireFill))) {

            updateHitTestResult(result, IntPoint(_x, _y));

            return true;

        }

    }

    return false;

}

enum MarkerType {

    Start,

    Mid,

    End

};

struct MarkerData {

    FloatPoint origin;

    FloatPoint subpathStart;

    double strokeWidth;

    FloatPoint inslopePoints[2];

    FloatPoint outslopePoints[2];

    MarkerType type;

    SVGResourceMarker* marker;

};

struct DrawMarkersData {

    DrawMarkersData(GraphicsContext*, SVGResourceMarker* startMarker, SVGResourceMarker* midMarker, double strokeWidth);

    GraphicsContext* context;

    int elementIndex;

    MarkerData previousMarkerData;

    SVGResourceMarker* midMarker;

};

DrawMarkersData::DrawMarkersData(GraphicsContext* c, SVGResourceMarker *start, SVGResourceMarker *mid, double strokeWidth)

    : context(c)

    , elementIndex(0)

    , midMarker(mid)

{

    previousMarkerData.origin = FloatPoint();

    previousMarkerData.subpathStart = FloatPoint();

    previousMarkerData.strokeWidth = strokeWidth;

    previousMarkerData.marker = start;

    previousMarkerData.type = Start;

}

static void drawMarkerWithData(GraphicsContext* context, MarkerData &data)

{

    if (!data.marker)

        return;

    FloatPoint inslopeChange = data.inslopePoints[1] - FloatSize(data.inslopePoints[0].x(), data.inslopePoints[0].y());

    FloatPoint outslopeChange = data.outslopePoints[1] - FloatSize(data.outslopePoints[0].x(), data.outslopePoints[0].y());

    static const double deg2rad = piDouble / 180.0;

    double inslope = atan2(inslopeChange.y(), inslopeChange.x()) / deg2rad;

    double outslope = atan2(outslopeChange.y(), outslopeChange.x()) / deg2rad;

    double angle = 0.0;

    switch (data.type) {

        case Start:

            angle = outslope;

            break;

        case Mid:

            angle = (inslope + outslope) / 2;

            break;

        case End:

            angle = inslope;

    }

    data.marker->draw(context, FloatRect(), data.origin.x(), data.origin.y(), data.strokeWidth, angle);

}

static inline void updateMarkerDataForElement(MarkerData& previousMarkerData, const PathElement* element)

{

    FloatPoint* points = element->points;

    switch (element->type) {

    case PathElementAddQuadCurveToPoint:

        // TODO

        previousMarkerData.origin = points[1];

        break;

    case PathElementAddCurveToPoint:

        previousMarkerData.inslopePoints[0] = points[1];

        previousMarkerData.inslopePoints[1] = points[2];

        previousMarkerData.origin = points[2];

        break;

    case PathElementMoveToPoint:

        previousMarkerData.subpathStart = points[0];

    case PathElementAddLineToPoint:

        previousMarkerData.inslopePoints[0] = previousMarkerData.origin;

        previousMarkerData.inslopePoints[1] = points[0];

        previousMarkerData.origin = points[0];

        break;

    case PathElementCloseSubpath:

        previousMarkerData.inslopePoints[0] = previousMarkerData.origin;

        previousMarkerData.inslopePoints[1] = points[0];

        previousMarkerData.origin = previousMarkerData.subpathStart;

        previousMarkerData.subpathStart = FloatPoint();

    }

}

static void drawStartAndMidMarkers(void* info, const PathElement* element)

{

    DrawMarkersData& data = *reinterpret_cast<DrawMarkersData*>(info);

    int elementIndex = data.elementIndex;

    MarkerData& previousMarkerData = data.previousMarkerData;

    FloatPoint* points = element->points;

    // First update the outslope for the previous element

    previousMarkerData.outslopePoints[0] = previousMarkerData.origin;

    previousMarkerData.outslopePoints[1] = points[0];

    // Draw the marker for the previous element

    if (elementIndex != 0)

        drawMarkerWithData(data.context, previousMarkerData);

    // Update our marker data for this element

    updateMarkerDataForElement(previousMarkerData, element);

    if (elementIndex == 1) {

        // After drawing the start marker, switch to drawing mid markers

        previousMarkerData.marker = data.midMarker;

        previousMarkerData.type = Mid;

    }

    data.elementIndex++;

}

FloatRect RenderPath::drawMarkersIfNeeded(GraphicsContext* context, const FloatRect& rect, const Path& path) const

{

    Document* doc = document();

    SVGElement* svgElement = static_cast<SVGElement*>(element());

    ASSERT(svgElement && svgElement->document() && svgElement->isStyled());

    SVGStyledElement* styledElement = static_cast<SVGStyledElement*>(svgElement);

    const SVGRenderStyle* svgStyle = style()->svgStyle();

    AtomicString startMarkerId(SVGURIReference::getTarget(svgStyle->startMarker()));

    AtomicString midMarkerId(SVGURIReference::getTarget(svgStyle->midMarker()));

    AtomicString endMarkerId(SVGURIReference::getTarget(svgStyle->endMarker()));

    SVGResourceMarker* startMarker = getMarkerById(doc, startMarkerId);

    SVGResourceMarker* midMarker = getMarkerById(doc, midMarkerId);

    SVGResourceMarker* endMarker = getMarkerById(doc, endMarkerId);

    if (!startMarker && !startMarkerId.isEmpty())

        svgElement->document()->accessSVGExtensions()->addPendingResource(startMarkerId, styledElement);

    else if (startMarker)

        startMarker->addClient(styledElement);

    if (!midMarker && !midMarkerId.isEmpty())

        svgElement->document()->accessSVGExtensions()->addPendingResource(midMarkerId, styledElement);

    else if (midMarker)

        midMarker->addClient(styledElement);

    if (!endMarker && !endMarkerId.isEmpty())

        svgElement->document()->accessSVGExtensions()->addPendingResource(endMarkerId, styledElement);

    else if (endMarker)

        endMarker->addClient(styledElement);

    if (!startMarker && !midMarker && !endMarker)

        return FloatRect();

    double strokeWidth = KSVGPainterFactory::cssPrimitiveToLength(this, svgStyle->strokeWidth(), 1.0);

    DrawMarkersData data(context, startMarker, midMarker, strokeWidth);

    path.apply(&data, drawStartAndMidMarkers);

    data.previousMarkerData.marker = endMarker;

    data.previousMarkerData.type = End;

    drawMarkerWithData(context, data.previousMarkerData);

    // We know the marker boundaries, only after they're drawn!

    // Otherwhise we'd need to do all the marker calculation twice

    // once here (through paint()) and once in absoluteClippedOverflowRect().

    FloatRect bounds;

    if (startMarker)

        bounds.unite(startMarker->cachedBounds());

    if (midMarker)

        bounds.unite(midMarker->cachedBounds());

    if (endMarker)

        bounds.unite(endMarker->cachedBounds());

    return bounds;

}

bool RenderPath::hasRelativeValues() const

{

    return static_cast<SVGStyledElement*>(element())->hasRelativeValues();

}

}

#endif // ENABLE(SVG)