cssstyleselector.cpp

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    applyDeclarations(true, true, firstUARule, lastUARule);
    
    // If our font got dirtied, go ahead and update it now.
    if (m_fontDirty)
        updateFont();

    // Line-height is set when we are sure we decided on the font-size
    if (m_lineHeightValue)
        applyProperty(CSSPropertyLineHeight, m_lineHeightValue);
    
    // Now do the normal priority properties.
    applyDeclarations(false, false, firstUARule, lastUARule);
    
    // Cache our border and background so that we can examine them later.
    cacheBorderAndBackground();
    
    applyDeclarations(false, false, lastUARule + 1, m_matchedDecls.size() - 1);
    applyDeclarations(false, true, firstAuthorRule, lastAuthorRule);
    applyDeclarations(false, true, firstUserRule, lastUserRule);
    applyDeclarations(false, true, firstUARule, lastUARule);
    
    // If our font got dirtied by one of the non-essential font props, 
    // go ahead and update it a second time.
    if (m_fontDirty)
        updateFont();
    // Clean up our style object's display and text decorations (among other fixups).
    adjustRenderStyle(style(), 0);

    // Now return the style.
    return m_style.release();
}

static void addIntrinsicMargins(RenderStyle* style)
{
    // Intrinsic margin value.
    const int intrinsicMargin = 2 * style->effectiveZoom();
    
    // FIXME: Using width/height alone and not also dealing with min-width/max-width is flawed.
    // FIXME: Using "quirk" to decide the margin wasn't set is kind of lame.
    if (style->width().isIntrinsicOrAuto()) {
        if (style->marginLeft().quirk())
            style->setMarginLeft(Length(intrinsicMargin, Fixed));
        if (style->marginRight().quirk())
            style->setMarginRight(Length(intrinsicMargin, Fixed));
    }

    if (style->height().isAuto()) {
        if (style->marginTop().quirk())
            style->setMarginTop(Length(intrinsicMargin, Fixed));
        if (style->marginBottom().quirk())
            style->setMarginBottom(Length(intrinsicMargin, Fixed));
    }
}

void CSSStyleSelector::adjustRenderStyle(RenderStyle* style, Element *e)
{
    // Cache our original display.
    style->setOriginalDisplay(style->display());

    if (style->display() != NONE) {
        // If we have a <td> that specifies a float property, in quirks mode we just drop the float
        // property.
        // Sites also commonly use display:inline/block on <td>s and <table>s.  In quirks mode we force
        // these tags to retain their display types.
        if (!m_checker.m_strictParsing && e) {
            if (e->hasTagName(tdTag)) {
                style->setDisplay(TABLE_CELL);
                style->setFloating(FNONE);
            }
            else if (e->hasTagName(tableTag))
                style->setDisplay(style->isDisplayInlineType() ? INLINE_TABLE : TABLE);
        }

        if (e && (e->hasTagName(tdTag) || e->hasTagName(thTag))) {
            if (style->whiteSpace() == KHTML_NOWRAP) {
                // Figure out if we are really nowrapping or if we should just
                // use normal instead.  If the width of the cell is fixed, then
                // we don't actually use NOWRAP.
                if (style->width().isFixed())
                    style->setWhiteSpace(NORMAL);
                else
                    style->setWhiteSpace(NOWRAP);
            }
        }

        // Tables never support the -webkit-* values for text-align and will reset back to the default.
        if (e && e->hasTagName(tableTag) && (style->textAlign() == WEBKIT_LEFT || style->textAlign() == WEBKIT_CENTER || style->textAlign() == WEBKIT_RIGHT))
            style->setTextAlign(TAAUTO);

        // Frames and framesets never honor position:relative or position:absolute.  This is necessary to
        // fix a crash where a site tries to position these objects.  They also never honor display.
        if (e && (e->hasTagName(frameTag) || e->hasTagName(framesetTag))) {
            style->setPosition(StaticPosition);
            style->setDisplay(BLOCK);
        }

        // Table headers with a text-align of auto will change the text-align to center.
        if (e && e->hasTagName(thTag) && style->textAlign() == TAAUTO)
            style->setTextAlign(CENTER);

        if (e && e->hasTagName(legendTag))
            style->setDisplay(BLOCK);

        // Mutate the display to BLOCK or TABLE for certain cases, e.g., if someone attempts to
        // position or float an inline, compact, or run-in.  Cache the original display, since it
        // may be needed for positioned elements that have to compute their static normal flow
        // positions.  We also force inline-level roots to be block-level.
        if (style->display() != BLOCK && style->display() != TABLE && style->display() != BOX &&
            (style->position() == AbsolutePosition || style->position() == FixedPosition || style->floating() != FNONE ||
             (e && e->document()->documentElement() == e))) {
            if (style->display() == INLINE_TABLE)
                style->setDisplay(TABLE);
            else if (style->display() == INLINE_BOX)
                style->setDisplay(BOX);
            else if (style->display() == LIST_ITEM) {
                // It is a WinIE bug that floated list items lose their bullets, so we'll emulate the quirk,
                // but only in quirks mode.
                if (!m_checker.m_strictParsing && style->floating() != FNONE)
                    style->setDisplay(BLOCK);
            }
            else
                style->setDisplay(BLOCK);
        }
        
        // After performing the display mutation, check table rows.  We do not honor position:relative on
        // table rows or cells.  This has been established in CSS2.1 (and caused a crash in containingBlock()
        // on some sites).
        if ((style->display() == TABLE_HEADER_GROUP || style->display() == TABLE_ROW_GROUP ||
             style->display() == TABLE_FOOTER_GROUP || style->display() == TABLE_ROW || style->display() == TABLE_CELL) &&
             style->position() == RelativePosition)
            style->setPosition(StaticPosition);
    }

    // Make sure our z-index value is only applied if the object is positioned.
    if (style->position() == StaticPosition)
        style->setHasAutoZIndex();

    // Auto z-index becomes 0 for the root element and transparent objects.  This prevents
    // cases where objects that should be blended as a single unit end up with a non-transparent
    // object wedged in between them.  Auto z-index also becomes 0 for objects that specify transforms/masks/reflections.
    if (style->hasAutoZIndex() && ((e && e->document()->documentElement() == e) || style->opacity() < 1.0f || 
        style->hasTransformRelatedProperty() || style->hasMask() || style->boxReflect()))
        style->setZIndex(0);
    
    // Button, legend, input, select and textarea all consider width values of 'auto' to be 'intrinsic'.
    // This will be important when we use block flows for all form controls.
    if (e && (e->hasTagName(legendTag) || e->hasTagName(buttonTag) || e->hasTagName(inputTag) ||
              e->hasTagName(selectTag) || e->hasTagName(textareaTag)
#if ENABLE(WML)
              || e->hasTagName(WMLNames::insertedLegendTag)
              || e->hasTagName(WMLNames::inputTag)
#endif
       )) {
        if (style->width().isAuto())
            style->setWidth(Length(Intrinsic));
    }

    // Finally update our text decorations in effect, but don't allow text-decoration to percolate through
    // tables, inline blocks, inline tables, or run-ins.
    if (style->display() == TABLE || style->display() == INLINE_TABLE || style->display() == RUN_IN
        || style->display() == INLINE_BLOCK || style->display() == INLINE_BOX)
        style->setTextDecorationsInEffect(style->textDecoration());
    else
        style->addToTextDecorationsInEffect(style->textDecoration());
    
    // If either overflow value is not visible, change to auto.
    if (style->overflowX() == OMARQUEE && style->overflowY() != OMARQUEE)
        style->setOverflowY(OMARQUEE);
    else if (style->overflowY() == OMARQUEE && style->overflowX() != OMARQUEE)
        style->setOverflowX(OMARQUEE);
    else if (style->overflowX() == OVISIBLE && style->overflowY() != OVISIBLE)
        style->setOverflowX(OAUTO);
    else if (style->overflowY() == OVISIBLE && style->overflowX() != OVISIBLE)
        style->setOverflowY(OAUTO);

    // Table rows, sections and the table itself will support overflow:hidden and will ignore scroll/auto.
    // FIXME: Eventually table sections will support auto and scroll.
    if (style->display() == TABLE || style->display() == INLINE_TABLE ||
        style->display() == TABLE_ROW_GROUP || style->display() == TABLE_ROW) {
        if (style->overflowX() != OVISIBLE && style->overflowX() != OHIDDEN) 
            style->setOverflowX(OVISIBLE);
        if (style->overflowY() != OVISIBLE && style->overflowY() != OHIDDEN) 
            style->setOverflowY(OVISIBLE);
    }

    // Menulists should have visible overflow
    if (style->appearance() == MenulistPart) {
        style->setOverflowX(OVISIBLE);
        style->setOverflowY(OVISIBLE);
    }

    // Cull out any useless layers and also repeat patterns into additional layers.
    style->adjustBackgroundLayers();
    style->adjustMaskLayers();

    // Do the same for animations and transitions.
    style->adjustAnimations();
    style->adjustTransitions();

    // Important: Intrinsic margins get added to controls before the theme has adjusted the style, since the theme will
    // alter fonts and heights/widths.
    if (e && e->isFormControlElement() && style->fontSize() >= 11) {
        // Don't apply intrinsic margins to image buttons.  The designer knows how big the images are,
        // so we have to treat all image buttons as though they were explicitly sized.
        if (!e->hasTagName(inputTag) || static_cast<HTMLInputElement*>(e)->inputType() != HTMLInputElement::IMAGE)
            addIntrinsicMargins(style);
    }

    // Let the theme also have a crack at adjusting the style.
    if (style->hasAppearance())
        theme()->adjustStyle(this, style, e, m_hasUAAppearance, m_borderData, m_backgroundData, m_backgroundColor);

#if ENABLE(SVG)
    if (e && e->isSVGElement()) {
        // Spec: http://www.w3.org/TR/SVG/masking.html#OverflowProperty
        if (style->overflowY() == OSCROLL)
            style->setOverflowY(OHIDDEN);
        else if (style->overflowY() == OAUTO)
            style->setOverflowY(OVISIBLE);

        if (style->overflowX() == OSCROLL)
            style->setOverflowX(OHIDDEN);
        else if (style->overflowX() == OAUTO)
            style->setOverflowX(OVISIBLE);

        // Only the root <svg> element in an SVG document fragment tree honors css position
        if (!(e->hasTagName(SVGNames::svgTag) && e->parentNode() && !e->parentNode()->isSVGElement()))
            style->setPosition(RenderStyle::initialPosition());
    }
#endif
}

void CSSStyleSelector::updateFont()
{
    checkForTextSizeAdjust();
    checkForGenericFamilyChange(style(), m_parentStyle);
    checkForZoomChange(style(), m_parentStyle);
    m_style->font().update(m_fontSelector);
    m_fontDirty = false;
}

void CSSStyleSelector::cacheBorderAndBackground()
{
    m_hasUAAppearance = m_style->hasAppearance();
    if (m_hasUAAppearance) {
        m_borderData = m_style->border();
        m_backgroundData = *m_style->backgroundLayers();
        m_backgroundColor = m_style->backgroundColor();
    }
}

PassRefPtr<CSSRuleList> CSSStyleSelector::styleRulesForElement(Element* e, bool authorOnly)
{
    if (!e || !e->document()->haveStylesheetsLoaded())
        return 0;

    m_checker.m_collectRulesOnly = true;

    initElementAndPseudoState(e);
    initForStyleResolve(e);

    if (!authorOnly) {
        int firstUARule = -1, lastUARule = -1;
        // First we match rules from the user agent sheet.
        matchUARules(firstUARule, lastUARule);

        // Now we check user sheet rules.
        if (m_matchAuthorAndUserStyles) {
            int firstUserRule = -1, lastUserRule = -1;
            matchRules(m_userStyle, firstUserRule, lastUserRule);
        }
    }

    if (m_matchAuthorAndUserStyles) {
        // Check the rules in author sheets.
        int firstAuthorRule = -1, lastAuthorRule = -1;
        matchRules(m_authorStyle, firstAuthorRule, lastAuthorRule);
    }

    m_checker.m_collectRulesOnly = false;
    
    return m_ruleList.release();
}

PassRefPtr<CSSRuleList> CSSStyleSelector::pseudoStyleRulesForElement(Element*, const String&, bool)
{
    // FIXME: Implement this.
    return 0;
}

bool CSSStyleSelector::checkSelector(CSSSelector* sel)
{
    m_dynamicPseudo = NOPSEUDO;

    // Check the selector
    SelectorMatch match = m_checker.checkSelector(sel, m_element, &m_selectorAttrs, m_dynamicPseudo, true, false, style(), m_parentStyle);
    if (match != SelectorMatches)
        return false;

    if (m_checker.m_pseudoStyle != NOPSEUDO && m_checker.m_pseudoStyle != m_dynamicPseudo)
        return false;

    return true;
}

// Recursive check of selectors and combinators
// It can return 3 different values:
// * SelectorMatches         - the selector matches the element e
// * SelectorFailsLocally    - the selector fails for the element e
// * SelectorFailsCompletely - the selector fails for e and any sibling or ancestor of e
CSSStyleSelector::SelectorMatch CSSStyleSelector::SelectorChecker::checkSelector(CSSSelector* sel, Element* e, HashSet<AtomicStringImpl*>* selectorAttrs, PseudoId& dynamicPseudo, bool isAncestor, bool isSubSelector, RenderStyle* elementStyle, RenderStyle* elementParentStyle) const
{
#if ENABLE(SVG)
    // Spec: CSS2 selectors cannot be applied to the (conceptually) cloned DOM tree
    // because its contents are not part of the formal document structure.
    if (e->isSVGElement() && e->isShadowNode())
        return SelectorFailsCompletely;
#endif

    // first selector has to match
    if (!checkOneSelector(sel, e, selectorAttrs, dynamicPseudo, isAncestor, isSubSelector, elementStyle, elementParentStyle))
        return SelectorFailsLocally;

    // The rest of the selectors has to match
    CSSSelector::Relation relation = sel->relation();

    // Prepare next sel
    sel = sel->tagHistory();
    if (!sel)
        return SelectorMatches;

    if (relation != CSSSelector::SubSelector)
        // Bail-out if this selector is irrelevant for the pseudoStyle
        if (m_pseudoStyle != NOPSEUDO && m_pseudoS