applystylecommand.cpp

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    CSSMutableStyleDeclaration::const_iterator end = style->end();
    for (CSSMutableStyleDeclaration::const_iterator it = style->begin(); it != end; ++it) {
        switch ((*it).id()) {
            case CSSPropertyColor:
                removeNodeAttribute(elem, colorAttr);
                break;
            case CSSPropertyFontFamily:
                removeNodeAttribute(elem, faceAttr);
                break;
            case CSSPropertyFontSize:
                removeNodeAttribute(elem, sizeAttr);
                break;
        }
    }

    if (isEmptyFontTag(elem))
        removeNodePreservingChildren(elem);
}

void ApplyStyleCommand::removeHTMLBidiEmbeddingStyle(CSSMutableStyleDeclaration *style, HTMLElement *elem)
{
    ASSERT(style);
    ASSERT(elem);

    if (!elem->hasAttribute(dirAttr))
        return;

    if (!style->getPropertyCSSValue(CSSPropertyUnicodeBidi) && !style->getPropertyCSSValue(CSSPropertyDirection))
        return;

    removeNodeAttribute(elem, dirAttr);

    // FIXME: should this be isSpanWithoutAttributesOrUnstyleStyleSpan?  Need a test.
    if (isUnstyledStyleSpan(elem))
        removeNodePreservingChildren(elem);
}

void ApplyStyleCommand::removeCSSStyle(CSSMutableStyleDeclaration* style, HTMLElement* elem)
{
    ASSERT(style);
    ASSERT(elem);

    CSSMutableStyleDeclaration* decl = elem->inlineStyleDecl();
    if (!decl)
        return;

    CSSMutableStyleDeclaration::const_iterator end = style->end();
    for (CSSMutableStyleDeclaration::const_iterator it = style->begin(); it != end; ++it) {
        CSSPropertyID propertyID = static_cast<CSSPropertyID>((*it).id());
        RefPtr<CSSValue> value = decl->getPropertyCSSValue(propertyID);
        if (value && (propertyID != CSSPropertyWhiteSpace || !isTabSpanNode(elem))) {
            removeCSSProperty(decl, propertyID);
            if (propertyID == CSSPropertyUnicodeBidi && !decl->getPropertyValue(CSSPropertyDirection).isEmpty())
                removeCSSProperty(decl, CSSPropertyDirection);
        }
    }

    // No need to serialize <foo style=""> if we just removed the last css property
    if (decl->length() == 0)
        removeNodeAttribute(elem, styleAttr);

    if (isSpanWithoutAttributesOrUnstyleStyleSpan(elem))
        removeNodePreservingChildren(elem);
}

static bool hasTextDecorationProperty(Node *node)
{
    if (!node->isElementNode())
        return false;

    RefPtr<CSSValue> value = computedStyle(node)->getPropertyCSSValue(CSSPropertyTextDecoration, DoNotUpdateLayout);
    return value && !equalIgnoringCase(value->cssText(), "none");
}

static Node* highestAncestorWithTextDecoration(Node *node)
{
    Node *result = NULL;

    for (Node *n = node; n; n = n->parentNode()) {
        if (hasTextDecorationProperty(n))
            result = n;
    }

    return result;
}

PassRefPtr<CSSMutableStyleDeclaration> ApplyStyleCommand::extractTextDecorationStyle(Node* node)
{
    ASSERT(node);
    ASSERT(node->isElementNode());
    
    // non-html elements not handled yet
    if (!node->isHTMLElement())
        return 0;

    HTMLElement *element = static_cast<HTMLElement *>(node);
    RefPtr<CSSMutableStyleDeclaration> style = element->inlineStyleDecl();
    if (!style)
        return 0;

    int properties[1] = { CSSPropertyTextDecoration };
    RefPtr<CSSMutableStyleDeclaration> textDecorationStyle = style->copyPropertiesInSet(properties, 1);

    RefPtr<CSSValue> property = style->getPropertyCSSValue(CSSPropertyTextDecoration);
    if (property && !equalIgnoringCase(property->cssText(), "none"))
        removeCSSProperty(style.get(), CSSPropertyTextDecoration);

    return textDecorationStyle.release();
}

PassRefPtr<CSSMutableStyleDeclaration> ApplyStyleCommand::extractAndNegateTextDecorationStyle(Node* node)
{
    ASSERT(node);
    ASSERT(node->isElementNode());
    
    // non-html elements not handled yet
    if (!node->isHTMLElement())
        return 0;

    RefPtr<CSSComputedStyleDeclaration> nodeStyle = computedStyle(node);
    ASSERT(nodeStyle);

    int properties[1] = { CSSPropertyTextDecoration };
    RefPtr<CSSMutableStyleDeclaration> textDecorationStyle = nodeStyle->copyPropertiesInSet(properties, 1);

    RefPtr<CSSValue> property = nodeStyle->getPropertyCSSValue(CSSPropertyTextDecoration);
    if (property && !equalIgnoringCase(property->cssText(), "none")) {
        RefPtr<CSSMutableStyleDeclaration> newStyle = textDecorationStyle->copy();
        newStyle->setProperty(CSSPropertyTextDecoration, "none");
        applyTextDecorationStyle(node, newStyle.get());
    }

    return textDecorationStyle.release();
}

void ApplyStyleCommand::applyTextDecorationStyle(Node *node, CSSMutableStyleDeclaration *style)
{
    ASSERT(node);

    if (!style || !style->cssText().length())
        return;

    if (node->isTextNode()) {
        RefPtr<HTMLElement> styleSpan = createStyleSpanElement(document());
        surroundNodeRangeWithElement(node, node, styleSpan.get());
        node = styleSpan.get();
    }

    if (!node->isElementNode())
        return;

    HTMLElement *element = static_cast<HTMLElement *>(node);
        
    StyleChange styleChange(style, Position(element, 0));
    if (styleChange.cssStyle().length() > 0) {
        String cssText = styleChange.cssStyle();
        CSSMutableStyleDeclaration *decl = element->inlineStyleDecl();
        if (decl)
            cssText += decl->cssText();
        setNodeAttribute(element, styleAttr, cssText);
    }
}

void ApplyStyleCommand::pushDownTextDecorationStyleAroundNode(Node* node, bool force)
{
    Node *highestAncestor = highestAncestorWithTextDecoration(node);
    
    if (highestAncestor) {
        Node *nextCurrent;
        Node *nextChild;
        for (Node *current = highestAncestor; current != node; current = nextCurrent) {
            ASSERT(current);
            
            nextCurrent = NULL;
            
            RefPtr<CSSMutableStyleDeclaration> decoration = force ? extractAndNegateTextDecorationStyle(current) : extractTextDecorationStyle(current);

            for (Node *child = current->firstChild(); child; child = nextChild) {
                nextChild = child->nextSibling();

                if (node == child) {
                    nextCurrent = child;
                } else if (node->isDescendantOf(child)) {
                    applyTextDecorationStyle(child, decoration.get());
                    nextCurrent = child;
                } else {
                    applyTextDecorationStyle(child, decoration.get());
                }
            }
        }
    }
}

void ApplyStyleCommand::pushDownTextDecorationStyleAtBoundaries(const Position &start, const Position &end)
{
    // We need to work in two passes. First we push down any inline
    // styles that set text decoration. Then we look for any remaining
    // styles (caused by stylesheets) and explicitly negate text
    // decoration while pushing down.

    pushDownTextDecorationStyleAroundNode(start.node(), false);
    updateLayout();
    pushDownTextDecorationStyleAroundNode(start.node(), true);

    pushDownTextDecorationStyleAroundNode(end.node(), false);
    updateLayout();
    pushDownTextDecorationStyleAroundNode(end.node(), true);
}

static int maxRangeOffset(Node *n)
{
    if (n->offsetInCharacters())
        return n->maxCharacterOffset();

    if (n->isElementNode())
        return n->childNodeCount();

    return 1;
}

void ApplyStyleCommand::removeInlineStyle(PassRefPtr<CSSMutableStyleDeclaration> style, const Position &start, const Position &end)
{
    ASSERT(start.isNotNull());
    ASSERT(end.isNotNull());
    ASSERT(start.node()->inDocument());
    ASSERT(end.node()->inDocument());
    ASSERT(Range::compareBoundaryPoints(start, end) <= 0);
    
    RefPtr<CSSValue> textDecorationSpecialProperty = style->getPropertyCSSValue(CSSPropertyWebkitTextDecorationsInEffect);

    if (textDecorationSpecialProperty) {
        pushDownTextDecorationStyleAtBoundaries(start.downstream(), end.upstream());
        style = style->copy();
        style->setProperty(CSSPropertyTextDecoration, textDecorationSpecialProperty->cssText(), style->getPropertyPriority(CSSPropertyWebkitTextDecorationsInEffect));
    }

    // The s and e variables store the positions used to set the ending selection after style removal
    // takes place. This will help callers to recognize when either the start node or the end node
    // are removed from the document during the work of this function.
    Position s = start;
    Position e = end;

    Node *node = start.node();
    while (node) {
        Node *next = node->traverseNextNode();
        if (node->isHTMLElement() && nodeFullySelected(node, start, end)) {
            HTMLElement *elem = static_cast<HTMLElement *>(node);
            Node *prev = elem->traversePreviousNodePostOrder();
            Node *next = elem->traverseNextNode();
            if (m_styledInlineElement && elem->hasTagName(m_styledInlineElement->tagQName()))
                removeNodePreservingChildren(elem);
            if (isHTMLStyleNode(style.get(), elem))
                removeHTMLStyleNode(elem);
            else {
                removeHTMLFontStyle(style.get(), elem);
                removeHTMLBidiEmbeddingStyle(style.get(), elem);
                removeCSSStyle(style.get(), elem);
            }
            if (!elem->inDocument()) {
                if (s.node() == elem) {
                    // Since elem must have been fully selected, and it is at the start
                    // of the selection, it is clear we can set the new s offset to 0.
                    ASSERT(s.offset() <= caretMinOffset(s.node()));
                    s = Position(next, 0);
                }
                if (e.node() == elem) {
                    // Since elem must have been fully selected, and it is at the end
                    // of the selection, it is clear we can set the new e offset to
                    // the max range offset of prev.
                    ASSERT(e.offset() >= maxRangeOffset(e.node()));
                    e = Position(prev, maxRangeOffset(prev));
                }
            }
        }
        if (node == end.node())
            break;
        node = next;
    }
    
    ASSERT(s.node()->inDocument());
    ASSERT(e.node()->inDocument());
    updateStartEnd(s, e);
}

bool ApplyStyleCommand::nodeFullySelected(Node *node, const Position &start, const Position &end) const
{
    ASSERT(node);
    ASSERT(node->isElementNode());

    Position pos = Position(node, node->childNodeCount()).upstream();
    return Range::compareBoundaryPoints(node, 0, start.node(), start.offset()) >= 0 &&
        Range::compareBoundaryPoints(pos, end) <= 0;
}

bool ApplyStyleCommand::nodeFullyUnselected(Node *node, const Position &start, const Position &end) const
{
    ASSERT(node);
    ASSERT(node->isElementNode());

    Position pos = Position(node, node->childNodeCount()).upstream();
    bool isFullyBeforeStart = Range::compareBoundaryPoints(pos, start) < 0;
    bool isFullyAfterEnd = Range::compareBoundaryPoints(node, 0, end.node(), end.offset()) > 0;

    return isFullyBeforeStart || isFullyAfterEnd;
}


bool ApplyStyleCommand::splitTextAtStartIfNeeded(const Position &start, const Position &end)
{
    if (start.node()->isTextNode() && start.offset() > caretMinOffset(start.node()) && start.offset() < caretMaxOffset(start.node())) {
        int endOffsetAdjustment = start.node() == end.node() ? start.offset() : 0;
        Text *text = static_cast<Text *>(start.node());
        splitTextNode(text, start.offset());
        updateStartEnd(Position(start.node(), 0), Position(end.node(), end.offset() - endOffsetAdjustment));
        return true;
    }
    return false;
}

bool ApplyStyleCommand::splitTextAtEndIfNeeded(const Position &start, const Position &end)
{
    if (end.node()->isTextNode() && end.offset() > caretMinOffset(end.node()) && end.offset() < caretMaxOffset(end.node())) {
        Text *text = static_cast<Text *>(end.node());
        splitTextNode(text, end.offset());