1 /*
2 * Copyright (C) 2012 Apple Computer, Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include "config.h"
27 #include "core/editing/SimplifyMarkupCommand.h"
28
29 #include "core/dom/NodeRenderStyle.h"
30 #include "core/dom/NodeTraversal.h"
31 #include "core/rendering/RenderInline.h"
32 #include "core/rendering/RenderObject.h"
33 #include "core/rendering/style/RenderStyle.h"
34
35 namespace blink {
36
SimplifyMarkupCommand(Document & document,Node * firstNode,Node * nodeAfterLast)37 SimplifyMarkupCommand::SimplifyMarkupCommand(Document& document, Node* firstNode, Node* nodeAfterLast)
38 : CompositeEditCommand(document), m_firstNode(firstNode), m_nodeAfterLast(nodeAfterLast)
39 {
40 }
41
doApply()42 void SimplifyMarkupCommand::doApply()
43 {
44 ContainerNode* rootNode = m_firstNode->parentNode();
45 WillBeHeapVector<RefPtrWillBeMember<ContainerNode> > nodesToRemove;
46
47 // Walk through the inserted nodes, to see if there are elements that could be removed
48 // without affecting the style. The goal is to produce leaner markup even when starting
49 // from a verbose fragment.
50 // We look at inline elements as well as non top level divs that don't have attributes.
51 for (Node* node = m_firstNode.get(); node && node != m_nodeAfterLast; node = NodeTraversal::next(*node)) {
52 if (node->hasChildren() || (node->isTextNode() && node->nextSibling()))
53 continue;
54
55 ContainerNode* startingNode = node->parentNode();
56 if (!startingNode)
57 continue;
58 RenderStyle* startingStyle = startingNode->renderStyle();
59 if (!startingStyle)
60 continue;
61 ContainerNode* currentNode = startingNode;
62 ContainerNode* topNodeWithStartingStyle = 0;
63 while (currentNode != rootNode) {
64 if (currentNode->parentNode() != rootNode && isRemovableBlock(currentNode))
65 nodesToRemove.append(currentNode);
66
67 currentNode = currentNode->parentNode();
68 if (!currentNode)
69 break;
70
71 if (!currentNode->renderer() || !currentNode->renderer()->isRenderInline() || toRenderInline(currentNode->renderer())->alwaysCreateLineBoxes())
72 continue;
73
74 if (currentNode->firstChild() != currentNode->lastChild()) {
75 topNodeWithStartingStyle = 0;
76 break;
77 }
78
79 if (!currentNode->renderStyle()->visualInvalidationDiff(*startingStyle).hasDifference())
80 topNodeWithStartingStyle = currentNode;
81
82 }
83 if (topNodeWithStartingStyle) {
84 for (ContainerNode* node = startingNode; node != topNodeWithStartingStyle; node = node->parentNode())
85 nodesToRemove.append(node);
86 }
87 }
88
89 // we perform all the DOM mutations at once.
90 for (size_t i = 0; i < nodesToRemove.size(); ++i) {
91 // FIXME: We can do better by directly moving children from nodesToRemove[i].
92 int numPrunedAncestors = pruneSubsequentAncestorsToRemove(nodesToRemove, i);
93 if (numPrunedAncestors < 0)
94 continue;
95 removeNodePreservingChildren(nodesToRemove[i], AssumeContentIsAlwaysEditable);
96 i += numPrunedAncestors;
97 }
98 }
99
pruneSubsequentAncestorsToRemove(WillBeHeapVector<RefPtrWillBeMember<ContainerNode>> & nodesToRemove,size_t startNodeIndex)100 int SimplifyMarkupCommand::pruneSubsequentAncestorsToRemove(WillBeHeapVector<RefPtrWillBeMember<ContainerNode> >& nodesToRemove, size_t startNodeIndex)
101 {
102 size_t pastLastNodeToRemove = startNodeIndex + 1;
103 for (; pastLastNodeToRemove < nodesToRemove.size(); ++pastLastNodeToRemove) {
104 if (nodesToRemove[pastLastNodeToRemove - 1]->parentNode() != nodesToRemove[pastLastNodeToRemove])
105 break;
106 ASSERT(nodesToRemove[pastLastNodeToRemove]->firstChild() == nodesToRemove[pastLastNodeToRemove]->lastChild());
107 }
108
109 ContainerNode* highestAncestorToRemove = nodesToRemove[pastLastNodeToRemove - 1].get();
110 RefPtrWillBeRawPtr<ContainerNode> parent = highestAncestorToRemove->parentNode();
111 if (!parent) // Parent has already been removed.
112 return -1;
113
114 if (pastLastNodeToRemove == startNodeIndex + 1)
115 return 0;
116
117 removeNode(nodesToRemove[startNodeIndex], AssumeContentIsAlwaysEditable);
118 insertNodeBefore(nodesToRemove[startNodeIndex], highestAncestorToRemove, AssumeContentIsAlwaysEditable);
119 removeNode(highestAncestorToRemove, AssumeContentIsAlwaysEditable);
120
121 return pastLastNodeToRemove - startNodeIndex - 1;
122 }
123
trace(Visitor * visitor)124 void SimplifyMarkupCommand::trace(Visitor* visitor)
125 {
126 visitor->trace(m_firstNode);
127 visitor->trace(m_nodeAfterLast);
128 CompositeEditCommand::trace(visitor);
129 }
130
131 } // namespace blink
132