1/*
2 * Copyright (C) 2012 Google 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 are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32#include "InspectorHistory.h"
33
34#include "Node.h"
35
36namespace WebCore {
37
38class UndoableStateMark : public InspectorHistory::Action {
39private:
40 ExceptionOr<void> perform() final { return { }; }
41 ExceptionOr<void> undo() final { return { }; }
42 ExceptionOr<void> redo() final { return { }; }
43 bool isUndoableStateMark() final { return true; }
44};
45
46ExceptionOr<void> InspectorHistory::perform(std::unique_ptr<Action> action)
47{
48 auto performResult = action->perform();
49 if (performResult.hasException())
50 return performResult.releaseException();
51
52 if (!action->mergeId().isEmpty() && m_afterLastActionIndex > 0 && action->mergeId() == m_history[m_afterLastActionIndex - 1]->mergeId())
53 m_history[m_afterLastActionIndex - 1]->merge(WTFMove(action));
54 else {
55 m_history.resize(m_afterLastActionIndex);
56 m_history.append(WTFMove(action));
57 ++m_afterLastActionIndex;
58 }
59 return { };
60}
61
62void InspectorHistory::markUndoableState()
63{
64 perform(std::make_unique<UndoableStateMark>());
65}
66
67ExceptionOr<void> InspectorHistory::undo()
68{
69 while (m_afterLastActionIndex > 0 && m_history[m_afterLastActionIndex - 1]->isUndoableStateMark())
70 --m_afterLastActionIndex;
71
72 while (m_afterLastActionIndex > 0) {
73 Action* action = m_history[m_afterLastActionIndex - 1].get();
74 auto undoResult = action->undo();
75 if (undoResult.hasException()) {
76 reset();
77 return undoResult.releaseException();
78 }
79 --m_afterLastActionIndex;
80 if (action->isUndoableStateMark())
81 break;
82 }
83
84 return { };
85}
86
87ExceptionOr<void> InspectorHistory::redo()
88{
89 while (m_afterLastActionIndex < m_history.size() && m_history[m_afterLastActionIndex]->isUndoableStateMark())
90 ++m_afterLastActionIndex;
91
92 while (m_afterLastActionIndex < m_history.size()) {
93 Action* action = m_history[m_afterLastActionIndex].get();
94 auto redoResult = action->redo();
95 if (redoResult.hasException()) {
96 reset();
97 return redoResult.releaseException();
98 }
99 ++m_afterLastActionIndex;
100 if (action->isUndoableStateMark())
101 break;
102 }
103 return { };
104}
105
106void InspectorHistory::reset()
107{
108 m_afterLastActionIndex = 0;
109 m_history.clear();
110}
111
112} // namespace WebCore
113