WebCore/editing/IndentOutdentCommand.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/editing/IndentOutdentCommand.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,374 @@
+/*
+ * Copyright (C) 2006, 2008 Apple 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 (IndentOutdentCommandINCLUDING, 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 "IndentOutdentCommand.h"
+
+#include "Document.h"
+#include "Element.h"
+#include "HTMLBlockquoteElement.h"
+#include "HTMLNames.h"
+#include "InsertLineBreakCommand.h"
+#include "InsertListCommand.h"
+#include "Range.h"
+#include "SplitElementCommand.h"
+#include "Text.h"
+#include "TextIterator.h"
+#include "htmlediting.h"
+#include "visible_units.h"
+#include <wtf/StdLibExtras.h>
+
+namespace WebCore {
+
+using namespace HTMLNames;
+
+static String indentBlockquoteString()
+{
+    DEFINE_STATIC_LOCAL(String, string, ("webkit-indent-blockquote"));
+    return string;
+}
+
+static PassRefPtr<HTMLBlockquoteElement> createIndentBlockquoteElement(Document* document)
+{
+    RefPtr<HTMLBlockquoteElement> element = HTMLBlockquoteElement::create(document);
+    element->setAttribute(classAttr, indentBlockquoteString());
+    element->setAttribute(styleAttr, "margin: 0 0 0 40px; border: none; padding: 0px;");
+    return element.release();
+}
+
+static bool isListOrIndentBlockquote(const Node* node)
+{
+    return node && (node->hasTagName(ulTag) || node->hasTagName(olTag) || node->hasTagName(blockquoteTag));
+}
+
+// This function can return -1 if we are unable to count the paragraphs between |start| and |end|.
+static int countParagraphs(const VisiblePosition& endOfFirstParagraph, const VisiblePosition& endOfLastParagraph)
+{
+    int count = 0;
+    VisiblePosition cur = endOfFirstParagraph;
+    while (cur != endOfLastParagraph) {
+        ++count;
+        cur = endOfParagraph(cur.next());
+        // If start is before a table and end is inside a table, we will never hit end because the
+        // whole table is considered a single paragraph.
+        if (cur.isNull())
+            return -1;
+    }
+    return count;
+}
+
+IndentOutdentCommand::IndentOutdentCommand(Document* document, EIndentType typeOfAction, int marginInPixels)
+    : CompositeEditCommand(document), m_typeOfAction(typeOfAction), m_marginInPixels(marginInPixels)
+{
+}
+
+bool IndentOutdentCommand::tryIndentingAsListItem(const VisiblePosition& endOfCurrentParagraph)
+{
+    // If our selection is not inside a list, bail out.
+    Node* lastNodeInSelectedParagraph = endOfCurrentParagraph.deepEquivalent().node();
+    RefPtr<Element> listNode = enclosingList(lastNodeInSelectedParagraph);
+    if (!listNode)
+        return false;
+
+    // Find the block that we want to indent.  If it's not a list item (e.g., a div inside a list item), we bail out.
+    Element* selectedListItem = static_cast<Element*>(enclosingBlock(lastNodeInSelectedParagraph));
+
+    // FIXME: we need to deal with the case where there is no li (malformed HTML)
+    if (!selectedListItem->hasTagName(liTag))
+        return false;
+    
+    // FIXME: previousElementSibling does not ignore non-rendered content like <span></span>.  Should we?
+    Element* previousList = selectedListItem->previousElementSibling();
+    Element* nextList = selectedListItem->nextElementSibling();
+
+    RefPtr<Element> newList = document()->createElement(listNode->tagQName(), false);
+    insertNodeBefore(newList, selectedListItem);
+
+    moveParagraphWithClones(startOfParagraph(endOfCurrentParagraph), endOfCurrentParagraph, newList.get(), selectedListItem);
+
+    if (canMergeLists(previousList, newList.get()))
+        mergeIdenticalElements(previousList, newList);
+    if (canMergeLists(newList.get(), nextList))
+        mergeIdenticalElements(newList, nextList);
+
+    return true;
+}
+    
+void IndentOutdentCommand::indentIntoBlockquote(const VisiblePosition& endOfCurrentParagraph, const VisiblePosition& endOfNextParagraph, RefPtr<Element>& targetBlockquote)
+{
+    Node* enclosingCell = 0;
+
+    Position start = startOfParagraph(endOfCurrentParagraph).deepEquivalent();
+    enclosingCell = enclosingNodeOfType(start, &isTableCell);
+    Node* nodeToSplitTo;
+    if (enclosingCell)
+        nodeToSplitTo = enclosingCell;
+    else if (enclosingList(start.node()))
+        nodeToSplitTo = enclosingBlock(start.node());
+    else
+        nodeToSplitTo = editableRootForPosition(start);
+
+    RefPtr<Node> outerBlock = (start.node() == nodeToSplitTo) ? start.node() : splitTreeToNode(start.node(), nodeToSplitTo);
+
+    if (!targetBlockquote) {
+        // Create a new blockquote and insert it as a child of the root editable element. We accomplish
+        // this by splitting all parents of the current paragraph up to that point.
+        targetBlockquote = createIndentBlockquoteElement(document());
+        insertNodeBefore(targetBlockquote, outerBlock);
+    }
+
+    moveParagraphWithClones(startOfParagraph(endOfCurrentParagraph), endOfCurrentParagraph, targetBlockquote.get(), outerBlock.get());
+    
+    // Don't put the next paragraph in the blockquote we just created for this paragraph unless 
+    // the next paragraph is in the same cell.
+    if (enclosingCell && enclosingCell != enclosingNodeOfType(endOfNextParagraph.deepEquivalent(), &isTableCell))
+        targetBlockquote = 0;
+}
+
+void IndentOutdentCommand::indentRegion(const VisiblePosition& startOfSelection, const VisiblePosition& endOfSelection)
+{
+    // Special case empty unsplittable elements because there's nothing to split
+    // and there's nothing to move.
+    Position start = startOfSelection.deepEquivalent().downstream();
+    if (isAtUnsplittableElement(start)) {
+        RefPtr<Element> blockquote = createIndentBlockquoteElement(document());
+        insertNodeAt(blockquote, start);
+        RefPtr<Element> placeholder = createBreakElement(document());
+        appendNode(placeholder, blockquote);
+        setEndingSelection(VisibleSelection(Position(placeholder.get(), 0), DOWNSTREAM));
+        return;
+    }
+
+    RefPtr<Element> blockquoteForNextIndent;
+    VisiblePosition endOfCurrentParagraph = endOfParagraph(startOfSelection);
+    VisiblePosition endAfterSelection = endOfParagraph(endOfParagraph(endOfSelection).next());
+    int endOfCurrentParagraphIndex = indexForVisiblePosition(endOfCurrentParagraph);
+    int endAfterSelectionIndex = indexForVisiblePosition(endAfterSelection);
+
+    // When indenting within a <pre> tag, we need to split each paragraph into a separate node for moveParagraphWithClones to work.
+    // However, splitting text nodes can cause endOfCurrentParagraph and endAfterSelection to point to an invalid position if we
+    // changed the text node it was pointing at.  So we have to reset these positions.
+    int numParagraphs = countParagraphs(endOfCurrentParagraph, endAfterSelection);
+    if (splitTextNodes(startOfParagraph(startOfSelection), numParagraphs + 1)) {
+        RefPtr<Range> endOfCurrentParagraphRange = TextIterator::rangeFromLocationAndLength(document()->documentElement(), endOfCurrentParagraphIndex, 0, true);
+        RefPtr<Range> endAfterSelectionRange = TextIterator::rangeFromLocationAndLength(document()->documentElement(), endAfterSelectionIndex, 0, true);
+        if (!endOfCurrentParagraphRange.get() || !endAfterSelectionRange.get()) {
+            ASSERT_NOT_REACHED();
+            return;
+        }
+        endOfCurrentParagraph = VisiblePosition(endOfCurrentParagraphRange->startPosition(), DOWNSTREAM);
+        endAfterSelection = VisiblePosition(endAfterSelectionRange->startPosition(), DOWNSTREAM);
+    }
+
+    while (endOfCurrentParagraph != endAfterSelection) {
+        // Iterate across the selected paragraphs...
+        VisiblePosition endOfNextParagraph = endOfParagraph(endOfCurrentParagraph.next());
+        if (tryIndentingAsListItem(endOfCurrentParagraph))
+            blockquoteForNextIndent = 0;
+        else
+            indentIntoBlockquote(endOfCurrentParagraph, endOfNextParagraph, blockquoteForNextIndent);
+
+        // indentIntoBlockquote could move more than one paragraph if the paragraph
+        // is in a list item or a table. As a result, endAfterSelection could refer to a position
+        // no longer in the document.
+        if (endAfterSelection.isNotNull() && !endAfterSelection.deepEquivalent().node()->inDocument())
+            break;
+        // Sanity check: Make sure our moveParagraph calls didn't remove endOfNextParagraph.deepEquivalent().node()
+        // If somehow we did, return to prevent crashes.
+        if (endOfNextParagraph.isNotNull() && !endOfNextParagraph.deepEquivalent().node()->inDocument()) {
+            ASSERT_NOT_REACHED();
+            return;
+        }
+        endOfCurrentParagraph = endOfNextParagraph;
+    }   
+}
+
+// Returns true if at least one text node was split.
+bool IndentOutdentCommand::splitTextNodes(const VisiblePosition& start, int numParagraphs)
+{
+    VisiblePosition currentParagraphStart = start;
+    bool hasSplit = false;
+    int paragraphCount;
+    for (paragraphCount = 0; paragraphCount < numParagraphs; ++paragraphCount) {
+        // If there are multiple paragraphs in a single text node, we split the text node into a separate node for each paragraph.
+        if (currentParagraphStart.deepEquivalent().node()->isTextNode() && currentParagraphStart.deepEquivalent().node() == startOfParagraph(currentParagraphStart.previous()).deepEquivalent().node()) {
+            Text* textNode = static_cast<Text *>(currentParagraphStart.deepEquivalent().node());
+            int offset = currentParagraphStart.deepEquivalent().offsetInContainerNode();
+            splitTextNode(textNode, offset);
+            currentParagraphStart = VisiblePosition(textNode, 0, VP_DEFAULT_AFFINITY);
+            hasSplit = true;
+        }
+        VisiblePosition nextParagraph = startOfParagraph(endOfParagraph(currentParagraphStart).next());
+        if (nextParagraph.isNull())
+            break;
+        currentParagraphStart = nextParagraph;
+    }
+    return hasSplit;
+}
+
+void IndentOutdentCommand::outdentParagraph()
+{
+    VisiblePosition visibleStartOfParagraph = startOfParagraph(endingSelection().visibleStart());
+    VisiblePosition visibleEndOfParagraph = endOfParagraph(visibleStartOfParagraph);
+
+    Node* enclosingNode = enclosingNodeOfType(visibleStartOfParagraph.deepEquivalent(), &isListOrIndentBlockquote);
+    if (!enclosingNode || !enclosingNode->parentNode()->isContentEditable())  // We can't outdent if there is no place to go!
+        return;
+
+    // Use InsertListCommand to remove the selection from the list
+    if (enclosingNode->hasTagName(olTag)) {
+        applyCommandToComposite(InsertListCommand::create(document(), InsertListCommand::OrderedList));
+        return;        
+    }
+    if (enclosingNode->hasTagName(ulTag)) {
+        applyCommandToComposite(InsertListCommand::create(document(), InsertListCommand::UnorderedList));
+        return;
+    }
+    
+    // The selection is inside a blockquote i.e. enclosingNode is a blockquote
+    VisiblePosition positionInEnclosingBlock = VisiblePosition(Position(enclosingNode, 0));
+    VisiblePosition startOfEnclosingBlock = startOfBlock(positionInEnclosingBlock);
+    VisiblePosition lastPositionInEnclosingBlock = VisiblePosition(Position(enclosingNode, enclosingNode->childNodeCount()));
+    VisiblePosition endOfEnclosingBlock = endOfBlock(lastPositionInEnclosingBlock);
+    if (visibleStartOfParagraph == startOfEnclosingBlock &&
+        visibleEndOfParagraph == endOfEnclosingBlock) {
+        // The blockquote doesn't contain anything outside the paragraph, so it can be totally removed.
+        Node* splitPoint = enclosingNode->nextSibling();
+        removeNodePreservingChildren(enclosingNode);
+        // outdentRegion() assumes it is operating on the first paragraph of an enclosing blockquote, but if there are multiply nested blockquotes and we've
+        // just removed one, then this assumption isn't true. By splitting the next containing blockquote after this node, we keep this assumption true
+        if (splitPoint) {
+            if (Node* splitPointParent = splitPoint->parentNode()) {
+                if (splitPointParent->hasTagName(blockquoteTag)
+                    && !splitPoint->hasTagName(blockquoteTag)
+                    && splitPointParent->parentNode()->isContentEditable()) // We can't outdent if there is no place to go!
+                    splitElement(static_cast<Element*>(splitPointParent), splitPoint);
+            }
+        }
+        
+        updateLayout();
+        visibleStartOfParagraph = VisiblePosition(visibleStartOfParagraph.deepEquivalent());
+        visibleEndOfParagraph = VisiblePosition(visibleEndOfParagraph.deepEquivalent());
+        if (visibleStartOfParagraph.isNotNull() && !isStartOfParagraph(visibleStartOfParagraph))
+            insertNodeAt(createBreakElement(document()), visibleStartOfParagraph.deepEquivalent());
+        if (visibleEndOfParagraph.isNotNull() && !isEndOfParagraph(visibleEndOfParagraph))
+            insertNodeAt(createBreakElement(document()), visibleEndOfParagraph.deepEquivalent());
+
+        return;
+    }
+    Node* enclosingBlockFlow = enclosingBlock(visibleStartOfParagraph.deepEquivalent().node());
+    RefPtr<Node> splitBlockquoteNode = enclosingNode;
+    if (enclosingBlockFlow != enclosingNode)
+        splitBlockquoteNode = splitTreeToNode(enclosingBlockFlow, enclosingNode, true);
+    else {
+        // We split the blockquote at where we start outdenting.
+        splitElement(static_cast<Element*>(enclosingNode), visibleStartOfParagraph.deepEquivalent().node());
+    }
+    RefPtr<Node> placeholder = createBreakElement(document());
+    insertNodeBefore(placeholder, splitBlockquoteNode);
+    moveParagraph(startOfParagraph(visibleStartOfParagraph), endOfParagraph(visibleEndOfParagraph), VisiblePosition(Position(placeholder.get(), 0)), true);
+}
+
+void IndentOutdentCommand::outdentRegion(const VisiblePosition& startOfSelection, const VisiblePosition& endOfSelection)
+{
+    VisiblePosition endOfLastParagraph = endOfParagraph(endOfSelection);
+
+    if (endOfParagraph(startOfSelection) == endOfLastParagraph) {
+        outdentParagraph();
+        return;
+    }
+    
+    Position originalSelectionEnd = endingSelection().end();
+    VisiblePosition endOfCurrentParagraph = endOfParagraph(startOfSelection);
+    VisiblePosition endAfterSelection = endOfParagraph(endOfParagraph(endOfSelection).next());
+
+    while (endOfCurrentParagraph != endAfterSelection) {
+        VisiblePosition endOfNextParagraph = endOfParagraph(endOfCurrentParagraph.next());
+        if (endOfCurrentParagraph == endOfLastParagraph)
+            setEndingSelection(VisibleSelection(originalSelectionEnd, DOWNSTREAM));
+        else
+            setEndingSelection(endOfCurrentParagraph);
+        
+        outdentParagraph();
+        
+        // outdentParagraph could move more than one paragraph if the paragraph
+        // is in a list item. As a result, endAfterSelection and endOfNextParagraph
+        // could refer to positions no longer in the document.
+        if (endAfterSelection.isNotNull() && !endAfterSelection.deepEquivalent().node()->inDocument())
+            break;
+            
+        if (endOfNextParagraph.isNotNull() && !endOfNextParagraph.deepEquivalent().node()->inDocument()) {
+            endOfCurrentParagraph = endingSelection().end();
+            endOfNextParagraph = endOfParagraph(endOfCurrentParagraph.next());
+        }
+        endOfCurrentParagraph = endOfNextParagraph;
+    }
+}
+
+void IndentOutdentCommand::doApply()
+{
+    if (endingSelection().isNone())
+        return;
+
+    if (!endingSelection().rootEditableElement())
+        return;
+        
+    VisiblePosition visibleEnd = endingSelection().visibleEnd();
+    VisiblePosition visibleStart = endingSelection().visibleStart();
+    // When a selection ends at the start of a paragraph, we rarely paint 
+    // the selection gap before that paragraph, because there often is no gap.  
+    // In a case like this, it's not obvious to the user that the selection 
+    // ends "inside" that paragraph, so it would be confusing if Indent/Outdent 
+    // operated on that paragraph.
+    // FIXME: We paint the gap before some paragraphs that are indented with left 
+    // margin/padding, but not others.  We should make the gap painting more consistent and 
+    // then use a left margin/padding rule here.
+    if (visibleEnd != visibleStart && isStartOfParagraph(visibleEnd))
+        setEndingSelection(VisibleSelection(visibleStart, visibleEnd.previous(true)));
+
+    VisibleSelection selection = selectionForParagraphIteration(endingSelection());
+    VisiblePosition startOfSelection = selection.visibleStart();
+    VisiblePosition endOfSelection = selection.visibleEnd();
+    
+    int startIndex = indexForVisiblePosition(startOfSelection);
+    int endIndex = indexForVisiblePosition(endOfSelection);
+    
+    ASSERT(!startOfSelection.isNull());
+    ASSERT(!endOfSelection.isNull());
+    
+    if (m_typeOfAction == Indent)
+        indentRegion(startOfSelection, endOfSelection);
+    else
+        outdentRegion(startOfSelection, endOfSelection);
+
+    updateLayout();
+    
+    RefPtr<Range> startRange = TextIterator::rangeFromLocationAndLength(document()->documentElement(), startIndex, 0, true);
+    RefPtr<Range> endRange = TextIterator::rangeFromLocationAndLength(document()->documentElement(), endIndex, 0, true);
+    if (startRange && endRange)
+        setEndingSelection(VisibleSelection(startRange->startPosition(), endRange->startPosition(), DOWNSTREAM));
+}
+
+}