replaceselectioncommand.cpp

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    // Paste at start or end of link goes outside of link.
    insertionPos = positionAvoidingSpecialElementBoundary(insertionPos);
    
    // FIXME: Can this wait until after the operation has been performed?  There doesn't seem to be
    // any work performed after this that queries or uses the typing style.
    if (Frame* frame = document()->frame())
        frame->clearTypingStyle();
    
    bool handledStyleSpans = handleStyleSpansBeforeInsertion(fragment, insertionPos);
    
    // We're finished if there is nothing to add.
    if (fragment.isEmpty() || !fragment.firstChild())
        return;
    
    // 1) Insert the content.
    // 2) Remove redundant styles and style tags, this inner <b> for example: <b>foo <b>bar</b> baz</b>.
    // 3) Merge the start of the added content with the content before the position being pasted into.
    // 4) Do one of the following: a) expand the last br if the fragment ends with one and it collapsed,
    // b) merge the last paragraph of the incoming fragment with the paragraph that contained the 
    // end of the selection that was pasted into, or c) handle an interchange newline at the end of the 
    // incoming fragment.
    // 5) Add spaces for smart replace.
    // 6) Select the replacement if requested, and match style if requested.
    
    VisiblePosition startOfInsertedContent, endOfInsertedContent;
    
    RefPtr<Node> refNode = fragment.firstChild();
    RefPtr<Node> node = refNode->nextSibling();
    
    fragment.removeNode(refNode);
    insertNodeAtAndUpdateNodesInserted(refNode, insertionPos);
    
    while (node) {
        Node* next = node->nextSibling();
        fragment.removeNode(node);
        insertNodeAfterAndUpdateNodesInserted(node, refNode.get());
        refNode = node;
        node = next;
    }
    
    removeUnrenderedTextNodesAtEnds();
    
    negateStyleRulesThatAffectAppearance();
    
    if (!handledStyleSpans)
        handleStyleSpans();
    
    // Mutation events (bug 20161) may have already removed the inserted content
    if (!m_firstNodeInserted || !m_firstNodeInserted->inDocument())
        return;
    
    endOfInsertedContent = positionAtEndOfInsertedContent();
    startOfInsertedContent = positionAtStartOfInsertedContent();
    
    // We inserted before the startBlock to prevent nesting, and the content before the startBlock wasn't in its own block and
    // didn't have a br after it, so the inserted content ended up in the same paragraph.
    if (startBlock && insertionPos.node() == startBlock->parentNode() && (unsigned)insertionPos.offset() < startBlock->nodeIndex() && !isStartOfParagraph(startOfInsertedContent))
        insertNodeAt(createBreakElement(document()).get(), startOfInsertedContent.deepEquivalent());
    
    Position lastPositionToSelect;
    
    bool interchangeNewlineAtEnd = fragment.hasInterchangeNewlineAtEnd();

    if (shouldRemoveEndBR(endBR, originalVisPosBeforeEndBR))
        removeNodeAndPruneAncestors(endBR);
    
    // Determine whether or not we should merge the end of inserted content with what's after it before we do
    // the start merge so that the start merge doesn't effect our decision.
    m_shouldMergeEnd = shouldMergeEnd(selectionEndWasEndOfParagraph);
    
    if (shouldMergeStart(selectionStartWasStartOfParagraph, fragment.hasInterchangeNewlineAtStart())) {
        // Bail to avoid infinite recursion.
        if (m_movingParagraph) {
            // setting display:inline does not work for td elements in quirks mode
            ASSERT(m_firstNodeInserted->hasTagName(tdTag));
            return;
        }
        VisiblePosition destination = startOfInsertedContent.previous();
        VisiblePosition startOfParagraphToMove = startOfInsertedContent;
        
        // Merging the the first paragraph of inserted content with the content that came
        // before the selection that was pasted into would also move content after 
        // the selection that was pasted into if: only one paragraph was being pasted, 
        // and it was not wrapped in a block, the selection that was pasted into ended 
        // at the end of a block and the next paragraph didn't start at the start of a block.
        // Insert a line break just after the inserted content to separate it from what 
        // comes after and prevent that from happening.
        VisiblePosition endOfInsertedContent = positionAtEndOfInsertedContent();
        if (startOfParagraph(endOfInsertedContent) == startOfParagraphToMove)
            insertNodeAt(createBreakElement(document()).get(), endOfInsertedContent.deepEquivalent());
        
        // FIXME: Maintain positions for the start and end of inserted content instead of keeping nodes.  The nodes are
        // only ever used to create positions where inserted content starts/ends.
        moveParagraph(startOfParagraphToMove, endOfParagraph(startOfParagraphToMove), destination);
        m_firstNodeInserted = endingSelection().visibleStart().deepEquivalent().downstream().node();
        if (!m_lastLeafInserted->inDocument())
            m_lastLeafInserted = endingSelection().visibleEnd().deepEquivalent().upstream().node();
    }
            
    endOfInsertedContent = positionAtEndOfInsertedContent();
    startOfInsertedContent = positionAtStartOfInsertedContent();
    
    if (interchangeNewlineAtEnd) {
        VisiblePosition next = endOfInsertedContent.next(true);

        if (selectionEndWasEndOfParagraph || !isEndOfParagraph(endOfInsertedContent) || next.isNull()) {
            if (!isStartOfParagraph(endOfInsertedContent)) {
                setEndingSelection(endOfInsertedContent);
                // Use a default paragraph element (a plain div) for the empty paragraph, using the last paragraph
                // block's style seems to annoy users.
                insertParagraphSeparator(true);

                // Select up to the paragraph separator that was added.
                lastPositionToSelect = endingSelection().visibleStart().deepEquivalent();
                updateNodesInserted(lastPositionToSelect.node());
            }
        } else {
            // Select up to the beginning of the next paragraph.
            lastPositionToSelect = next.deepEquivalent().downstream();
        }
        
    } else
        mergeEndIfNeeded();
    
    handlePasteAsQuotationNode();
    
    endOfInsertedContent = positionAtEndOfInsertedContent();
    startOfInsertedContent = positionAtStartOfInsertedContent();
    
    // Add spaces for smart replace.
    if (m_smartReplace && currentRoot) {
        // Disable smart replace for password fields.
        Node* start = currentRoot->shadowAncestorNode();
        if (start->hasTagName(inputTag) && static_cast<HTMLInputElement*>(start)->inputType() == HTMLInputElement::PASSWORD)
            m_smartReplace = false;
    }
    if (m_smartReplace) {
        bool needsTrailingSpace = !isEndOfParagraph(endOfInsertedContent) &&
                                  !isCharacterSmartReplaceExempt(endOfInsertedContent.characterAfter(), false);
        if (needsTrailingSpace) {
            RenderObject* renderer = m_lastLeafInserted->renderer();
            bool collapseWhiteSpace = !renderer || renderer->style()->collapseWhiteSpace();
            Node* endNode = positionAtEndOfInsertedContent().deepEquivalent().upstream().node();
            if (endNode->isTextNode()) {
                Text* text = static_cast<Text*>(endNode);
                insertTextIntoNode(text, text->length(), collapseWhiteSpace ? nonBreakingSpaceString() : " ");
            } else {
                RefPtr<Node> node = document()->createEditingTextNode(collapseWhiteSpace ? nonBreakingSpaceString() : " ");
                insertNodeAfterAndUpdateNodesInserted(node, endNode);
            }
        }
    
        bool needsLeadingSpace = !isStartOfParagraph(startOfInsertedContent) &&
                                 !isCharacterSmartReplaceExempt(startOfInsertedContent.previous().characterAfter(), true);
        if (needsLeadingSpace) {
            RenderObject* renderer = m_lastLeafInserted->renderer();
            bool collapseWhiteSpace = !renderer || renderer->style()->collapseWhiteSpace();
            Node* startNode = positionAtStartOfInsertedContent().deepEquivalent().downstream().node();
            if (startNode->isTextNode()) {
                Text* text = static_cast<Text*>(startNode);
                insertTextIntoNode(text, 0, collapseWhiteSpace ? nonBreakingSpaceString() : " ");
            } else {
                RefPtr<Node> node = document()->createEditingTextNode(collapseWhiteSpace ? nonBreakingSpaceString() : " ");
                // Don't updateNodesInserted.  Doing so would set m_lastLeafInserted to be the node containing the 
                // leading space, but m_lastLeafInserted is supposed to mark the end of pasted content.
                insertNodeBefore(node, startNode);
                // FIXME: Use positions to track the start/end of inserted content.
                m_firstNodeInserted = node;
            }
        }
    }
    
    completeHTMLReplacement(lastPositionToSelect);
}

bool ReplaceSelectionCommand::shouldRemoveEndBR(Node* endBR, const VisiblePosition& originalVisPosBeforeEndBR)
{
    if (!endBR || !endBR->inDocument())
        return false;
        
    VisiblePosition visiblePos(Position(endBR, 0));
    
    // Don't remove the br if nothing was inserted.
    if (visiblePos.previous() == originalVisPosBeforeEndBR)
        return false;
    
    // Remove the br if it is collapsed away and so is unnecessary.
    if (!document()->inStrictMode() && isEndOfBlock(visiblePos) && !isStartOfParagraph(visiblePos))
        return true;
        
    // A br that was originally holding a line open should be displaced by inserted content or turned into a line break.
    // A br that was originally acting as a line break should still be acting as a line break, not as a placeholder.
    return isStartOfParagraph(visiblePos) && isEndOfParagraph(visiblePos);
}

void ReplaceSelectionCommand::completeHTMLReplacement(const Position &lastPositionToSelect)
{
    Position start;
    Position end;

    // FIXME: This should never not be the case.
    if (m_firstNodeInserted && m_firstNodeInserted->inDocument() && m_lastLeafInserted && m_lastLeafInserted->inDocument()) {
        
        start = positionAtStartOfInsertedContent().deepEquivalent();
        end = positionAtEndOfInsertedContent().deepEquivalent();
        
        // FIXME (11475): Remove this and require that the creator of the fragment to use nbsps.
        rebalanceWhitespaceAt(start);
        rebalanceWhitespaceAt(end);

        if (m_matchStyle) {
            ASSERT(m_insertionStyle);
            applyStyle(m_insertionStyle.get(), start, end);
        }    
        
        if (lastPositionToSelect.isNotNull())
            end = lastPositionToSelect;
    } else if (lastPositionToSelect.isNotNull())
        start = end = lastPositionToSelect;
    else
        return;
    
    if (m_selectReplacement)
        setEndingSelection(VisibleSelection(start, end, SEL_DEFAULT_AFFINITY));
    else
        setEndingSelection(VisibleSelection(end, SEL_DEFAULT_AFFINITY));
}

EditAction ReplaceSelectionCommand::editingAction() const
{
    return m_editAction;
}

void ReplaceSelectionCommand::insertNodeAfterAndUpdateNodesInserted(PassRefPtr<Node> insertChild, Node* refChild)
{
    Node* nodeToUpdate = insertChild.get(); // insertChild will be cleared when passed
    insertNodeAfter(insertChild, refChild);
    updateNodesInserted(nodeToUpdate);
}

void ReplaceSelectionCommand::insertNodeAtAndUpdateNodesInserted(PassRefPtr<Node> insertChild, const Position& p)
{
    Node* nodeToUpdate = insertChild.get(); // insertChild will be cleared when passed
    insertNodeAt(insertChild, p);
    updateNodesInserted(nodeToUpdate);
}

void ReplaceSelectionCommand::insertNodeBeforeAndUpdateNodesInserted(PassRefPtr<Node> insertChild, Node* refChild)
{
    Node* nodeToUpdate = insertChild.get(); // insertChild will be cleared when passed
    insertNodeBefore(insertChild, refChild);
    updateNodesInserted(nodeToUpdate);
}

void ReplaceSelectionCommand::updateNodesInserted(Node *node)
{
    if (!node)
        return;

    if (!m_firstNodeInserted)
        m_firstNodeInserted = node;
    
    if (node == m_lastLeafInserted)
        return;
    
    m_lastLeafInserted = node->lastDescendant();
}

} // namespace WebCore