svginlinetextbox.cpp

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    // If we are past the last glyph of this box, don't mark it as 'hit'
    if (x >= charAtPos.x + glyphRect.width() && closestOffsetInBox == (int) end())
        return false;

    return true;
}

int SVGInlineTextBox::offsetForPosition(int, bool) const
{
    // SVG doesn't use the offset <-> position selection system. 
    ASSERT_NOT_REACHED();
    return 0;
}

int SVGInlineTextBox::positionForOffset(int) const
{
    // SVG doesn't use the offset <-> position selection system. 
    ASSERT_NOT_REACHED();
    return 0;
}

bool SVGInlineTextBox::nodeAtPoint(const HitTestRequest&, HitTestResult& result, int x, int y, int tx, int ty)
{
    ASSERT(!isLineBreak());

    IntRect rect = selectionRect(0, 0, 0, len());
    if (renderer()->style()->visibility() == VISIBLE && rect.contains(x, y)) {
        renderer()->updateHitTestResult(result, IntPoint(x - tx, y - ty));
        return true;
    }

    return false;
}

IntRect SVGInlineTextBox::selectionRect(int, int, int startPos, int endPos)
{
    if (startPos >= endPos)
        return IntRect();

    // TODO: Actually respect startPos/endPos - we're returning the _full_ selectionRect
    // here. This won't lead to visible bugs, but to extra work being done. Investigate.
    SVGRootInlineBox* rootBox = svgRootInlineBox();
    if (!rootBox)
        return IntRect();

    SVGInlineTextBoxSelectionRectWalker walkerCallback;
    SVGTextChunkWalker<SVGInlineTextBoxSelectionRectWalker> walker(&walkerCallback, &SVGInlineTextBoxSelectionRectWalker::chunkPortionCallback);

    rootBox->walkTextChunks(&walker, this);
    return enclosingIntRect(walkerCallback.selectionRect());
}

void SVGInlineTextBox::paintCharacters(RenderObject::PaintInfo& paintInfo, int tx, int ty, const SVGChar& svgChar, const UChar* chars, int length, SVGPaintServer* activePaintServer)
{
    if (renderer()->style()->visibility() != VISIBLE || paintInfo.phase == PaintPhaseOutline)
        return;

    ASSERT(paintInfo.phase != PaintPhaseSelfOutline && paintInfo.phase != PaintPhaseChildOutlines);

    RenderText* text = textRenderer();
    ASSERT(text);

    bool isPrinting = text->document()->printing();

    // Determine whether or not we're selected.
    bool haveSelection = !isPrinting && selectionState() != RenderObject::SelectionNone;
    if (!haveSelection && paintInfo.phase == PaintPhaseSelection)
        // When only painting the selection, don't bother to paint if there is none.
        return;

    // Determine whether or not we have a composition.
    bool containsComposition = text->document()->frame()->editor()->compositionNode() == text->node();
    bool useCustomUnderlines = containsComposition && text->document()->frame()->editor()->compositionUsesCustomUnderlines();

    // Set our font
    RenderStyle* styleToUse = text->style(isFirstLineStyle());
    const Font& font = styleToUse->font();

    TransformationMatrix ctm = svgChar.characterTransform();
    if (!ctm.isIdentity())
        paintInfo.context->concatCTM(ctm);

    // 1. Paint backgrounds behind text if needed.  Examples of such backgrounds include selection
    // and marked text.
    if (paintInfo.phase != PaintPhaseSelection && !isPrinting) {
#if PLATFORM(MAC)
        // Custom highlighters go behind everything else.
        if (styleToUse->highlight() != nullAtom && !paintInfo.context->paintingDisabled())
            paintCustomHighlight(tx, ty, styleToUse->highlight());
#endif

        if (containsComposition && !useCustomUnderlines)
            paintCompositionBackground(paintInfo.context, tx, ty, styleToUse, font, 
                                       text->document()->frame()->editor()->compositionStart(),
                                       text->document()->frame()->editor()->compositionEnd());
        
        paintDocumentMarkers(paintInfo.context, tx, ty, styleToUse, font, true);

        if (haveSelection && !useCustomUnderlines) {
            int boxStartOffset = chars - text->characters() - start();
            paintSelection(boxStartOffset, svgChar, chars, length, paintInfo.context, styleToUse, font);
        }
    }

    // Set a text shadow if we have one.
    // FIXME: Support multiple shadow effects.  Need more from the CG API before
    // we can do this.
    bool setShadow = false;
    if (styleToUse->textShadow()) {
        paintInfo.context->setShadow(IntSize(styleToUse->textShadow()->x, styleToUse->textShadow()->y),
                                     styleToUse->textShadow()->blur, styleToUse->textShadow()->color);
        setShadow = true;
    }

    IntPoint origin((int) svgChar.x, (int) svgChar.y);
    TextRun run = svgTextRunForInlineTextBox(chars, length, styleToUse, this, svgChar.x);

#if ENABLE(SVG_FONTS)
    // SVG Fonts need access to the paint server used to draw the current text chunk.
    // They need to be able to call renderPath() on a SVGPaintServer object.
    run.setActivePaintServer(activePaintServer);
#endif

    paintInfo.context->drawText(font, run, origin);

    if (paintInfo.phase != PaintPhaseSelection) {
        paintDocumentMarkers(paintInfo.context, tx, ty, styleToUse, font, false);

        if (useCustomUnderlines) {
            const Vector<CompositionUnderline>& underlines = text->document()->frame()->editor()->customCompositionUnderlines();
            size_t numUnderlines = underlines.size();
            
            for (size_t index = 0; index < numUnderlines; ++index) {
                const CompositionUnderline& underline = underlines[index];
                
                if (underline.endOffset <= start())
                    // underline is completely before this run.  This might be an underline that sits
                    // before the first run we draw, or underlines that were within runs we skipped 
                    // due to truncation.
                    continue;
                
                if (underline.startOffset <= end()) {
                    // underline intersects this run.  Paint it.
                    paintCompositionUnderline(paintInfo.context, tx, ty, underline);
                    if (underline.endOffset > end() + 1)
                        // underline also runs into the next run. Bail now, no more marker advancement.
                        break;
                } else
                    // underline is completely after this run, bail.  A later run will paint it.
                    break;
            }
        }
        
    }

    if (setShadow)
        paintInfo.context->clearShadow();

    if (!ctm.isIdentity())
        paintInfo.context->concatCTM(ctm.inverse());
}

void SVGInlineTextBox::paintSelection(int boxStartOffset, const SVGChar& svgChar, const UChar*, int length, GraphicsContext* p, RenderStyle* style, const Font& font)
{
    if (selectionState() == RenderObject::SelectionNone)
        return;

    int startPos, endPos;
    selectionStartEnd(startPos, endPos);

    if (startPos >= endPos)
        return;

    Color textColor = style->color();
    Color color = renderer()->selectionBackgroundColor();
    if (!color.isValid() || color.alpha() == 0)
        return;

    // If the text color ends up being the same as the selection background, invert the selection
    // background.  This should basically never happen, since the selection has transparency.
    if (textColor == color)
        color = Color(0xff - color.red(), 0xff - color.green(), 0xff - color.blue());

    // Map from text box positions and a given start offset to chunk positions
    // 'boxStartOffset' represents the beginning of the text chunk.
    if ((startPos > boxStartOffset && endPos > boxStartOffset + length) || boxStartOffset >= endPos)
        return;

    if (endPos > boxStartOffset + length)
        endPos = boxStartOffset + length;

    if (startPos < boxStartOffset)
        startPos = boxStartOffset;

    ASSERT(startPos >= boxStartOffset);
    ASSERT(endPos <= boxStartOffset + length);
    ASSERT(startPos < endPos);

    p->save();

    int adjust = startPos >= boxStartOffset ? boxStartOffset : 0;
    p->drawHighlightForText(font, svgTextRunForInlineTextBox(textRenderer()->text()->characters() + start() + boxStartOffset, length, style, this, svgChar.x),
                            IntPoint((int) svgChar.x, (int) svgChar.y - font.ascent()),
                            font.ascent() + font.descent(), color, startPos - adjust, endPos - adjust);

    p->restore();
}

static inline Path pathForDecoration(ETextDecoration decoration, RenderObject* object, float x, float y, float width)
{
    float thickness = SVGRenderStyle::cssPrimitiveToLength(object, object->style()->svgStyle()->strokeWidth(), 1.0f);

    const Font& font = object->style()->font();
    thickness = max(thickness * powf(font.size(), 2.0f) / font.unitsPerEm(), 1.0f);

    if (decoration == UNDERLINE)
        y += thickness * 1.5f; // For compatibility with Batik/Opera
    else if (decoration == OVERLINE)
        y += thickness;

    float halfThickness = thickness / 2.0f;
    return Path::createRectangle(FloatRect(x + halfThickness, y, width - 2.0f * halfThickness, thickness));
}

void SVGInlineTextBox::paintDecoration(ETextDecoration decoration, GraphicsContext* context, int tx, int ty, int width, const SVGChar& svgChar, const SVGTextDecorationInfo& info)
{
    if (renderer()->style()->visibility() != VISIBLE)
        return;

    // This function does NOT accept combinated text decorations. It's meant to be invoked for just one.
    ASSERT(decoration == TDNONE || decoration == UNDERLINE || decoration == OVERLINE || decoration == LINE_THROUGH || decoration == BLINK);

    bool isFilled = info.fillServerMap.contains(decoration);
    bool isStroked = info.strokeServerMap.contains(decoration);

    if (!isFilled && !isStroked)
        return;

    int baseline = renderer()->style(m_firstLine)->font().ascent();
    if (decoration == UNDERLINE)
        ty += baseline;
    else if (decoration == LINE_THROUGH)
        ty += 2 * baseline / 3;

    context->save();
    context->beginPath();

    TransformationMatrix ctm = svgChar.characterTransform();
    if (!ctm.isIdentity())
        context->concatCTM(ctm);

    if (isFilled) {
        if (RenderObject* fillObject = info.fillServerMap.get(decoration)) {
            if (SVGPaintServer* fillPaintServer = SVGPaintServer::fillPaintServer(fillObject->style(), fillObject)) {
                context->addPath(pathForDecoration(decoration, fillObject, tx, ty, width));
                fillPaintServer->draw(context, fillObject, ApplyToFillTargetType);
            }
        }
    }

    if (isStroked) {
        if (RenderObject* strokeObject = info.strokeServerMap.get(decoration)) {
            if (SVGPaintServer* strokePaintServer = SVGPaintServer::strokePaintServer(strokeObject->style(), strokeObject)) {
                context->addPath(pathForDecoration(decoration, strokeObject, tx, ty, width));
                strokePaintServer->draw(context, strokeObject, ApplyToStrokeTargetType);
            }
        }
    }

    context->restore();
}

} // namespace WebCore

#endif