WebCore/editing/InsertParagraphSeparatorCommand.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/editing/InsertParagraphSeparatorCommand.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,399 @@
+/*
+ * Copyright (C) 2005, 2006 Apple Computer, Inc.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#include "config.h"
+#include "InsertParagraphSeparatorCommand.h"
+
+#include "CSSComputedStyleDeclaration.h"
+#include "CSSMutableStyleDeclaration.h"
+#include "CSSPropertyNames.h"
+#include "Document.h"
+#include "HTMLElement.h"
+#include "HTMLNames.h"
+#include "InsertLineBreakCommand.h"
+#include "Logging.h"
+#include "RenderObject.h"
+#include "Text.h"
+#include "htmlediting.h"
+#include "visible_units.h"
+#include "ApplyStyleCommand.h"
+
+namespace WebCore {
+
+using namespace HTMLNames;
+
+// When inserting a new line, we want to avoid nesting empty divs if we can.  Otherwise, when
+// pasting, it's easy to have each new line be a div deeper than the previous.  E.g., in the case
+// below, we want to insert at ^ instead of |.
+// <div>foo<div>bar</div>|</div>^
+static Element* highestVisuallyEquivalentDivBelowRoot(Element* startBlock)
+{
+    Element* curBlock = startBlock;
+    // We don't want to return a root node (if it happens to be a div, e.g., in a document fragment) because there are no
+    // siblings for us to append to.
+    while (!curBlock->nextSibling() && curBlock->parentElement()->hasTagName(divTag) && curBlock->parentElement()->parentElement()) {
+        NamedNodeMap* attributes = curBlock->parentElement()->attributes(true);
+        if (attributes && !attributes->isEmpty())
+            break;
+        curBlock = curBlock->parentElement();
+    }
+    return curBlock;
+}
+
+InsertParagraphSeparatorCommand::InsertParagraphSeparatorCommand(Document *document, bool mustUseDefaultParagraphElement) 
+    : CompositeEditCommand(document)
+    , m_mustUseDefaultParagraphElement(mustUseDefaultParagraphElement)
+{
+}
+
+bool InsertParagraphSeparatorCommand::preservesTypingStyle() const
+{
+    return true;
+}
+
+void InsertParagraphSeparatorCommand::calculateStyleBeforeInsertion(const Position &pos)
+{
+    // It is only important to set a style to apply later if we're at the boundaries of
+    // a paragraph. Otherwise, content that is moved as part of the work of the command
+    // will lend their styles to the new paragraph without any extra work needed.
+    VisiblePosition visiblePos(pos, VP_DEFAULT_AFFINITY);
+    if (!isStartOfParagraph(visiblePos) && !isEndOfParagraph(visiblePos))
+        return;
+    
+    m_style = ApplyStyleCommand::editingStyleAtPosition(pos, IncludeTypingStyle);
+}
+
+void InsertParagraphSeparatorCommand::applyStyleAfterInsertion(Node* originalEnclosingBlock)
+{
+    // Not only do we break out of header tags, but we also do not preserve the typing style,
+    // in order to match other browsers.
+    if (originalEnclosingBlock->hasTagName(h1Tag) ||
+        originalEnclosingBlock->hasTagName(h2Tag) ||
+        originalEnclosingBlock->hasTagName(h3Tag) ||
+        originalEnclosingBlock->hasTagName(h4Tag) ||
+        originalEnclosingBlock->hasTagName(h5Tag))
+        return;
+        
+    if (!m_style)
+        return;
+    
+    prepareEditingStyleToApplyAt(m_style.get(), endingSelection().start());
+
+    if (m_style->length() > 0)
+        applyStyle(m_style.get());
+}
+
+bool InsertParagraphSeparatorCommand::shouldUseDefaultParagraphElement(Node* enclosingBlock) const
+{
+    if (m_mustUseDefaultParagraphElement)
+        return true;
+    
+    // Assumes that if there was a range selection, it was already deleted.
+    if (!isEndOfBlock(endingSelection().visibleStart()))
+        return false;
+
+    return enclosingBlock->hasTagName(h1Tag) ||
+           enclosingBlock->hasTagName(h2Tag) ||
+           enclosingBlock->hasTagName(h3Tag) ||
+           enclosingBlock->hasTagName(h4Tag) ||
+           enclosingBlock->hasTagName(h5Tag);
+}
+
+void InsertParagraphSeparatorCommand::getAncestorsInsideBlock(const Node* insertionNode, Element* outerBlock, Vector<Element*>& ancestors)
+{
+    ancestors.clear();
+    
+    // Build up list of ancestors elements between the insertion node and the outer block.
+    if (insertionNode != outerBlock) {
+        for (Element* n = insertionNode->parentElement(); n && n != outerBlock; n = n->parentElement())
+            ancestors.append(n);
+    }
+}
+
+PassRefPtr<Element> InsertParagraphSeparatorCommand::cloneHierarchyUnderNewBlock(const Vector<Element*>& ancestors, PassRefPtr<Element> blockToInsert)
+{
+    // Make clones of ancestors in between the start node and the start block.
+    RefPtr<Element> parent = blockToInsert;
+    for (size_t i = ancestors.size(); i != 0; --i) {
+        RefPtr<Element> child = ancestors[i - 1]->cloneElementWithoutChildren();
+        appendNode(child, parent);
+        parent = child.release();
+    }
+    
+    return parent.release();
+}
+
+void InsertParagraphSeparatorCommand::doApply()
+{
+    bool splitText = false;
+    if (endingSelection().isNone())
+        return;
+    
+    Position insertionPosition = endingSelection().start();
+        
+    EAffinity affinity = endingSelection().affinity();
+        
+    // Delete the current selection.
+    if (endingSelection().isRange()) {
+        calculateStyleBeforeInsertion(insertionPosition);
+        deleteSelection(false, true);
+        insertionPosition = endingSelection().start();
+        affinity = endingSelection().affinity();
+    }
+    
+    // FIXME: The rangeCompliantEquivalent conversion needs to be moved into enclosingBlock.
+    Node* startBlockNode = enclosingBlock(rangeCompliantEquivalent(insertionPosition).node());
+    Position canonicalPos = VisiblePosition(insertionPosition).deepEquivalent();
+    Element* startBlock = static_cast<Element*>(startBlockNode);
+    if (!startBlockNode
+            || !startBlockNode->isElementNode()
+            || !startBlock->parentNode()
+            || isTableCell(startBlock)
+            || startBlock->hasTagName(formTag)
+            // FIXME: If the node is hidden, we don't have a canonical position so we will do the wrong thing for tables and <hr>. https://bugs.webkit.org/show_bug.cgi?id=40342
+            || (!canonicalPos.isNull() && canonicalPos.node()->renderer() && canonicalPos.node()->renderer()->isTable())
+            || (!canonicalPos.isNull() && canonicalPos.node()->hasTagName(hrTag))) {
+        applyCommandToComposite(InsertLineBreakCommand::create(document()));
+        return;
+    }
+    
+    // Use the leftmost candidate.
+    insertionPosition = insertionPosition.upstream();
+    if (!insertionPosition.isCandidate())
+        insertionPosition = insertionPosition.downstream();
+
+    // Adjust the insertion position after the delete
+    insertionPosition = positionAvoidingSpecialElementBoundary(insertionPosition);
+    VisiblePosition visiblePos(insertionPosition, affinity);
+    calculateStyleBeforeInsertion(insertionPosition);
+
+    //---------------------------------------------------------------------
+    // Handle special case of typing return on an empty list item
+    if (breakOutOfEmptyListItem())
+        return;
+
+    //---------------------------------------------------------------------
+    // Prepare for more general cases.
+
+    bool isFirstInBlock = isStartOfBlock(visiblePos);
+    bool isLastInBlock = isEndOfBlock(visiblePos);
+    bool nestNewBlock = false;
+
+    // Create block to be inserted.
+    RefPtr<Element> blockToInsert;
+    if (startBlock == startBlock->rootEditableElement()) {
+        blockToInsert = createDefaultParagraphElement(document());
+        nestNewBlock = true;
+    } else if (shouldUseDefaultParagraphElement(startBlock)) 
+        blockToInsert = createDefaultParagraphElement(document());
+    else
+        blockToInsert = startBlock->cloneElementWithoutChildren();
+
+    //---------------------------------------------------------------------
+    // Handle case when position is in the last visible position in its block,
+    // including when the block is empty. 
+    if (isLastInBlock) {
+        if (nestNewBlock) {
+            if (isFirstInBlock && !lineBreakExistsAtVisiblePosition(visiblePos)) {
+                // The block is empty.  Create an empty block to
+                // represent the paragraph that we're leaving.
+                RefPtr<Element> extraBlock = createDefaultParagraphElement(document());
+                appendNode(extraBlock, startBlock);
+                appendBlockPlaceholder(extraBlock);
+            }
+            appendNode(blockToInsert, startBlock);
+        } else {
+            // We can get here if we pasted a copied portion of a blockquote with a newline at the end and are trying to paste it
+            // into an unquoted area. We then don't want the newline within the blockquote or else it will also be quoted.
+            if (Node* highestBlockquote = highestEnclosingNodeOfType(canonicalPos, &isMailBlockquote))
+                startBlock = static_cast<Element*>(highestBlockquote);
+
+            // Most of the time we want to stay at the nesting level of the startBlock (e.g., when nesting within lists).  However,
+            // for div nodes, this can result in nested div tags that are hard to break out of.
+            Element* siblingNode = startBlock;
+            if (blockToInsert->hasTagName(divTag))
+                siblingNode = highestVisuallyEquivalentDivBelowRoot(startBlock);
+            insertNodeAfter(blockToInsert, siblingNode);
+        }
+
+        // Recreate the same structure in the new paragraph.
+        
+        Vector<Element*> ancestors;
+        getAncestorsInsideBlock(insertionPosition.node(), startBlock, ancestors);      
+        RefPtr<Element> parent = cloneHierarchyUnderNewBlock(ancestors, blockToInsert);
+        
+        appendBlockPlaceholder(parent);
+
+        setEndingSelection(VisibleSelection(Position(parent.get(), 0), DOWNSTREAM));
+        return;
+    }
+    
+
+    //---------------------------------------------------------------------
+    // Handle case when position is in the first visible position in its block, and
+    // similar case where previous position is in another, presumeably nested, block.
+    if (isFirstInBlock || !inSameBlock(visiblePos, visiblePos.previous())) {
+        Node *refNode;
+        if (isFirstInBlock && !nestNewBlock)
+            refNode = startBlock;
+        else if (insertionPosition.node() == startBlock && nestNewBlock) {
+            refNode = startBlock->childNode(insertionPosition.deprecatedEditingOffset());
+            ASSERT(refNode); // must be true or we'd be in the end of block case
+        } else
+            refNode = insertionPosition.node();
+
+        // find ending selection position easily before inserting the paragraph
+        insertionPosition = insertionPosition.downstream();
+        
+        insertNodeBefore(blockToInsert, refNode);
+
+        // Recreate the same structure in the new paragraph.
+
+        Vector<Element*> ancestors;
+        getAncestorsInsideBlock(positionAvoidingSpecialElementBoundary(insertionPosition).node(), startBlock, ancestors);
+        
+        appendBlockPlaceholder(cloneHierarchyUnderNewBlock(ancestors, blockToInsert));
+        
+        // In this case, we need to set the new ending selection.
+        setEndingSelection(VisibleSelection(insertionPosition, DOWNSTREAM));
+        return;
+    }
+
+    //---------------------------------------------------------------------
+    // Handle the (more complicated) general case,
+
+    // All of the content in the current block after visiblePos is
+    // about to be wrapped in a new paragraph element.  Add a br before 
+    // it if visiblePos is at the start of a paragraph so that the 
+    // content will move down a line.
+    if (isStartOfParagraph(visiblePos)) {
+        RefPtr<Element> br = createBreakElement(document());
+        insertNodeAt(br.get(), insertionPosition);
+        insertionPosition = positionInParentAfterNode(br.get());
+    }
+    
+    // Move downstream. Typing style code will take care of carrying along the 
+    // style of the upstream position.
+    insertionPosition = insertionPosition.downstream();
+
+    // At this point, the insertionPosition's node could be a container, and we want to make sure we include
+    // all of the correct nodes when building the ancestor list.  So this needs to be the deepest representation of the position
+    // before we walk the DOM tree.
+    insertionPosition = VisiblePosition(insertionPosition).deepEquivalent();
+
+    // Build up list of ancestors in between the start node and the start block.
+    Vector<Element*> ancestors;
+    getAncestorsInsideBlock(insertionPosition.node(), startBlock, ancestors);
+
+    // Make sure we do not cause a rendered space to become unrendered.
+    // FIXME: We need the affinity for pos, but pos.downstream() does not give it
+    Position leadingWhitespace = insertionPosition.leadingWhitespacePosition(VP_DEFAULT_AFFINITY);
+    // FIXME: leadingWhitespacePosition is returning the position before preserved newlines for positions
+    // after the preserved newline, causing the newline to be turned into a nbsp.
+    if (leadingWhitespace.isNotNull() && leadingWhitespace.node()->isTextNode()) {
+        Text* textNode = static_cast<Text*>(leadingWhitespace.node());
+        ASSERT(!textNode->renderer() || textNode->renderer()->style()->collapseWhiteSpace());
+        replaceTextInNode(textNode, leadingWhitespace.deprecatedEditingOffset(), 1, nonBreakingSpaceString());
+    }
+    
+    // Split at pos if in the middle of a text node.
+    if (insertionPosition.node()->isTextNode()) {
+        Text* textNode = static_cast<Text*>(insertionPosition.node());
+        bool atEnd = (unsigned)insertionPosition.deprecatedEditingOffset() >= textNode->length();
+        if (insertionPosition.deprecatedEditingOffset() > 0 && !atEnd) {
+            splitTextNode(textNode, insertionPosition.deprecatedEditingOffset());
+            insertionPosition.moveToOffset(0);
+            visiblePos = VisiblePosition(insertionPosition);
+            splitText = true;
+        }
+    }
+
+    // Put the added block in the tree.
+    if (nestNewBlock)
+        appendNode(blockToInsert.get(), startBlock);
+    else
+        insertNodeAfter(blockToInsert.get(), startBlock);
+
+    updateLayout();
+    
+    // Make clones of ancestors in between the start node and the outer block.
+    RefPtr<Element> parent = cloneHierarchyUnderNewBlock(ancestors, blockToInsert);
+
+    // If the paragraph separator was inserted at the end of a paragraph, an empty line must be
+    // created.  All of the nodes, starting at visiblePos, are about to be added to the new paragraph 
+    // element.  If the first node to be inserted won't be one that will hold an empty line open, add a br.
+    if (isEndOfParagraph(visiblePos) && !lineBreakExistsAtVisiblePosition(visiblePos))
+        appendNode(createBreakElement(document()).get(), blockToInsert.get());
+        
+    // Move the start node and the siblings of the start node.
+    if (insertionPosition.node() != startBlock) {
+        Node* n = insertionPosition.node();
+        if (insertionPosition.deprecatedEditingOffset() >= caretMaxOffset(n))
+            n = n->nextSibling();
+
+        while (n && n != blockToInsert) {
+            Node *next = n->nextSibling();
+            removeNode(n);
+            appendNode(n, parent.get());
+            n = next;
+        }
+    }            
+
+    // Move everything after the start node.
+    if (!ancestors.isEmpty()) {
+        Element* leftParent = ancestors.first();
+        while (leftParent && leftParent != startBlock) {
+            parent = parent->parentElement();
+            if (!parent)
+                break;
+            Node* n = leftParent->nextSibling();
+            while (n && n != blockToInsert) {
+                Node* next = n->nextSibling();
+                removeNode(n);
+                appendNode(n, parent.get());
+                n = next;
+            }
+            leftParent = leftParent->parentElement();
+        }
+    }
+
+    // Handle whitespace that occurs after the split
+    if (splitText) {
+        updateLayout();
+        insertionPosition = Position(insertionPosition.node(), 0);
+        if (!insertionPosition.isRenderedCharacter()) {
+            // Clear out all whitespace and insert one non-breaking space
+            ASSERT(!insertionPosition.node()->renderer() || insertionPosition.node()->renderer()->style()->collapseWhiteSpace());
+            deleteInsignificantTextDownstream(insertionPosition);
+            if (insertionPosition.node()->isTextNode())
+                insertTextIntoNode(static_cast<Text*>(insertionPosition.node()), 0, nonBreakingSpaceString());
+        }
+    }
+
+    setEndingSelection(VisibleSelection(Position(blockToInsert.get(), 0), DOWNSTREAM));
+    applyStyleAfterInsertion(startBlock);
+}
+
+} // namespace WebCore