applystylecommand.cpp

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    , m_style(CSSMutableStyleDeclaration::create())
    , m_editingAction(editingAction)
    , m_propertyLevel(PropertyDefault)
    , m_start(endingSelection().start().downstream())
    , m_end(endingSelection().end().upstream())
    , m_useEndingSelection(true)
    , m_styledInlineElement(element)
    , m_removeOnly(removeOnly)
{
}

void ApplyStyleCommand::updateStartEnd(const Position& newStart, const Position& newEnd)
{
    ASSERT(Range::compareBoundaryPoints(newEnd, newStart) >= 0);

    if (!m_useEndingSelection && (newStart != m_start || newEnd != m_end))
        m_useEndingSelection = true;

    setEndingSelection(VisibleSelection(newStart, newEnd, VP_DEFAULT_AFFINITY));
    m_start = newStart;
    m_end = newEnd;
}

Position ApplyStyleCommand::startPosition()
{
    if (m_useEndingSelection)
        return endingSelection().start();
    
    return m_start;
}

Position ApplyStyleCommand::endPosition()
{
    if (m_useEndingSelection)
        return endingSelection().end();
    
    return m_end;
}

void ApplyStyleCommand::doApply()
{
    switch (m_propertyLevel) {
        case PropertyDefault: {
            // apply the block-centric properties of the style
            RefPtr<CSSMutableStyleDeclaration> blockStyle = m_style->copyBlockProperties();
            if (blockStyle->length())
                applyBlockStyle(blockStyle.get());
            // apply any remaining styles to the inline elements
            // NOTE: hopefully, this string comparison is the same as checking for a non-null diff
            if (blockStyle->length() < m_style->length() || m_styledInlineElement) {
                RefPtr<CSSMutableStyleDeclaration> inlineStyle = m_style->copy();
                applyRelativeFontStyleChange(inlineStyle.get());
                blockStyle->diff(inlineStyle.get());
                applyInlineStyle(inlineStyle.get());
            }
            break;
        }
        case ForceBlockProperties:
            // Force all properties to be applied as block styles.
            applyBlockStyle(m_style.get());
            break;
    }
}

EditAction ApplyStyleCommand::editingAction() const
{
    return m_editingAction;
}

void ApplyStyleCommand::applyBlockStyle(CSSMutableStyleDeclaration *style)
{
    // update document layout once before removing styles
    // so that we avoid the expense of updating before each and every call
    // to check a computed style
    updateLayout();

    // get positions we want to use for applying style
    Position start = startPosition();
    Position end = endPosition();
    if (Range::compareBoundaryPoints(end, start) < 0) {
        Position swap = start;
        start = end;
        end = swap;
    }
        
    VisiblePosition visibleStart(start);
    VisiblePosition visibleEnd(end);
    // Save and restore the selection endpoints using their indices in the document, since
    // addBlockStyleIfNeeded may moveParagraphs, which can remove these endpoints.
    // Calculate start and end indices from the start of the tree that they're in.
    Node* scope = highestAncestor(visibleStart.deepEquivalent().node());
    Position rangeStart(scope, 0);
    RefPtr<Range> startRange = Range::create(document(), rangeStart, rangeCompliantEquivalent(visibleStart.deepEquivalent()));
    RefPtr<Range> endRange = Range::create(document(), rangeStart, rangeCompliantEquivalent(visibleEnd.deepEquivalent()));
    int startIndex = TextIterator::rangeLength(startRange.get(), true);
    int endIndex = TextIterator::rangeLength(endRange.get(), true);
    
    VisiblePosition paragraphStart(startOfParagraph(visibleStart));
    VisiblePosition nextParagraphStart(endOfParagraph(paragraphStart).next());
    VisiblePosition beyondEnd(endOfParagraph(visibleEnd).next());
    while (paragraphStart.isNotNull() && paragraphStart != beyondEnd) {
        StyleChange styleChange(style, paragraphStart.deepEquivalent());
        if (styleChange.cssStyle().length() > 0 || m_removeOnly) {
            RefPtr<Node> block = enclosingBlock(paragraphStart.deepEquivalent().node());
            RefPtr<Node> newBlock = moveParagraphContentsToNewBlockIfNecessary(paragraphStart.deepEquivalent());
            if (newBlock)
                block = newBlock;
            ASSERT(block->isHTMLElement());
            if (block->isHTMLElement()) {
                removeCSSStyle(style, static_cast<HTMLElement*>(block.get()));
                if (!m_removeOnly)
                    addBlockStyle(styleChange, static_cast<HTMLElement*>(block.get()));
            }
        }
        paragraphStart = nextParagraphStart;
        nextParagraphStart = endOfParagraph(paragraphStart).next();
    }
    
    startRange = TextIterator::rangeFromLocationAndLength(static_cast<Element*>(scope), startIndex, 0, true);
    endRange = TextIterator::rangeFromLocationAndLength(static_cast<Element*>(scope), endIndex, 0, true);
    if (startRange && endRange)
        updateStartEnd(startRange->startPosition(), endRange->startPosition());
}

#define NoFontDelta (0.0f)
#define MinimumFontSize (0.1f)

void ApplyStyleCommand::applyRelativeFontStyleChange(CSSMutableStyleDeclaration *style)
{
    RefPtr<CSSValue> value = style->getPropertyCSSValue(CSSPropertyFontSize);
    if (value) {
        // Explicit font size overrides any delta.
        style->removeProperty(CSSPropertyWebkitFontSizeDelta);
        return;
    }

    // Get the adjustment amount out of the style.
    value = style->getPropertyCSSValue(CSSPropertyWebkitFontSizeDelta);
    if (!value)
        return;
    float adjustment = NoFontDelta;
    if (value->cssValueType() == CSSValue::CSS_PRIMITIVE_VALUE) {
        CSSPrimitiveValue *primitiveValue = static_cast<CSSPrimitiveValue *>(value.get());
        if (primitiveValue->primitiveType() == CSSPrimitiveValue::CSS_PX) {
            // Only PX handled now. If we handle more types in the future, perhaps
            // a switch statement here would be more appropriate.
            adjustment = primitiveValue->getFloatValue();
        }
    }
    style->removeProperty(CSSPropertyWebkitFontSizeDelta);
    if (adjustment == NoFontDelta)
        return;
    
    Position start = startPosition();
    Position end = endPosition();
    if (Range::compareBoundaryPoints(end, start) < 0) {
        Position swap = start;
        start = end;
        end = swap;
    }
    
    // Join up any adjacent text nodes.
    if (start.node()->isTextNode()) {
        joinChildTextNodes(start.node()->parentNode(), start, end);
        start = startPosition();
        end = endPosition();
    }
    if (end.node()->isTextNode() && start.node()->parentNode() != end.node()->parentNode()) {
        joinChildTextNodes(end.node()->parentNode(), start, end);
        start = startPosition();
        end = endPosition();
    }

    // Split the start text nodes if needed to apply style.
    bool splitStart = splitTextAtStartIfNeeded(start, end); 
    if (splitStart) {
        start = startPosition();
        end = endPosition();
    }
    bool splitEnd = splitTextAtEndIfNeeded(start, end);
    if (splitEnd) {
        start = startPosition();
        end = endPosition();
    }

    // Calculate loop end point.
    // If the end node is before the start node (can only happen if the end node is
    // an ancestor of the start node), we gather nodes up to the next sibling of the end node
    Node *beyondEnd;
    if (start.node()->isDescendantOf(end.node()))
        beyondEnd = end.node()->traverseNextSibling();
    else
        beyondEnd = end.node()->traverseNextNode();
    
    start = start.upstream(); // Move upstream to ensure we do not add redundant spans.
    Node *startNode = start.node();
    if (startNode->isTextNode() && start.offset() >= caretMaxOffset(startNode)) // Move out of text node if range does not include its characters.
        startNode = startNode->traverseNextNode();

    // Store away font size before making any changes to the document.
    // This ensures that changes to one node won't effect another.
    HashMap<Node*, float> startingFontSizes;
    for (Node *node = startNode; node != beyondEnd; node = node->traverseNextNode())
        startingFontSizes.set(node, computedFontSize(node));

    // These spans were added by us. If empty after font size changes, they can be removed.
    Vector<RefPtr<HTMLElement> > unstyledSpans;
    
    Node* lastStyledNode = 0;
    for (Node* node = startNode; node != beyondEnd; node = node->traverseNextNode()) {
        RefPtr<HTMLElement> element;
        if (node->isHTMLElement()) {
            // Only work on fully selected nodes.
            if (!nodeFullySelected(node, start, end))
                continue;
            element = static_cast<HTMLElement*>(node);
        } else if (node->isTextNode() && node->renderer() && node->parentNode() != lastStyledNode) {
            // Last styled node was not parent node of this text node, but we wish to style this
            // text node. To make this possible, add a style span to surround this text node.
            RefPtr<HTMLElement> span = createStyleSpanElement(document());
            surroundNodeRangeWithElement(node, node, span.get());
            element = span.release();
        }  else {
            // Only handle HTML elements and text nodes.
            continue;
        }
        lastStyledNode = node;

        CSSMutableStyleDeclaration* inlineStyleDecl = element->getInlineStyleDecl();
        float currentFontSize = computedFontSize(node);
        float desiredFontSize = max(MinimumFontSize, startingFontSizes.get(node) + adjustment);
        RefPtr<CSSValue> value = inlineStyleDecl->getPropertyCSSValue(CSSPropertyFontSize);
        if (value) {
            inlineStyleDecl->removeProperty(CSSPropertyFontSize, true);
            currentFontSize = computedFontSize(node);
        }
        if (currentFontSize != desiredFontSize) {
            inlineStyleDecl->setProperty(CSSPropertyFontSize, String::number(desiredFontSize) + "px", false, false);
            setNodeAttribute(element.get(), styleAttr, inlineStyleDecl->cssText());
        }
        if (inlineStyleDecl->length() == 0) {
            removeNodeAttribute(element.get(), styleAttr);
            // FIXME: should this be isSpanWithoutAttributesOrUnstyleStyleSpan?  Need a test.
            if (isUnstyledStyleSpan(element.get()))
                unstyledSpans.append(element.release());
        }
    }

    size_t size = unstyledSpans.size();
    for (size_t i = 0; i < size; ++i)
        removeNodePreservingChildren(unstyledSpans[i].get());
}

#undef NoFontDelta
#undef MinimumFontSize

static Node* dummySpanAncestorForNode(const Node* node)
{
    while (node && !isStyleSpan(node))
        node = node->parent();
    
    return node ? node->parent() : 0;
}

void ApplyStyleCommand::cleanupUnstyledAppleStyleSpans(Node* dummySpanAncestor)
{
    if (!dummySpanAncestor)
        return;

    // Dummy spans are created when text node is split, so that style information
    // can be propagated, which can result in more splitting. If a dummy span gets
    // cloned/split, the new node is always a sibling of it. Therefore, we scan
    // all the children of the dummy's parent
    Node* next;
    for (Node* node = dummySpanAncestor->firstChild(); node; node = next) {
        next = node->nextSibling();
        if (isUnstyledStyleSpan(node))
            removeNodePreservingChildren(node);
        node = next;
    }
}

HTMLElement* ApplyStyleCommand::splitAncestorsWithUnicodeBidi(Node* node, bool before, RefPtr<CSSPrimitiveValue> allowedDirection)
{
    // We are allowed to leave the highest ancestor with unicode-bidi unsplit if it is unicode-bidi: embed and direction: allowedDirection.
    // In that case, we return the unsplit ancestor. Otherwise, we return 0.
    Node* block = enclosingBlock(node);
    if (!block)
        return 0;

    Node* highestAncestorWithUnicodeBidi = 0;
    Node* nextHighestAncestorWithUnicodeBidi = 0;
    RefPtr<CSSPrimitiveValue> highestAncestorUnicodeBidi;
    for (Node* n = node->parent(); n != block; n = n->parent()) {
        RefPtr<CSSValue> unicodeBidi = computedStyle(n)->getPropertyCSSValue(CSSPropertyUnicodeBidi);
        if (unicodeBidi) {
            ASSERT(unicodeBidi->isPrimitiveValue());
            if (static_cast<CSSPrimitiveValue*>(unicodeBidi.get())->getIdent() != CSSValueNormal) {
                highestAncestorUnicodeBidi = static_cast<CSSPrimitiveValue*>(unicodeBidi.get());
                nextHighestAncestorWithUnicodeBidi = highestAncestorWithUnicodeBidi;
                highestAncestorWithUnicodeBidi = n;
            }
        }
    }

    if (!highestAncestorWithUnicodeBidi)
        return 0;

    HTMLElement* unsplitAncestor = 0;

    if (allowedDirection && highestAncestorUnicodeBidi->getIdent() != CSSValueBidiOverride) {
        RefPtr<CSSValue> highestAncestorDirection = computedStyle(highestAncestorWithUnicodeBidi)->getPropertyCSSValue(CSSPropertyDirection);
        ASSERT(highestAncestorDirection->isPrimitiveValue());
        if (static_cast<CSSPrimitiveValue*>(highestAncestorDirection.get())->getIdent() == allowedDirection->getIdent() && highestAncestorWithUnicodeBidi->isHTMLElement()) {
            if (!nextHighestAncestorWithUnicodeBidi)
                return static_cast<HTMLElement*>(highestAncestorWithUnicodeBidi);

            unsplitAncestor = static_cast<HTMLElement*>(highestAncestorWithUnicodeBidi);
            highestAncestorWithUnicodeBidi = nextHighestAncestorWithUnicodeBidi;
        }
    }

    // Split every ancestor through highest ancestor with embedding.
    Node* n = node;
    while (true) {
        Element* parent = static_cast<Element*>(n->parent());