1/*
2 * Copyright (C) 2011 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 "core/editing/RenderedPosition.h"
33
34#include "core/dom/Position.h"
35#include "core/editing/VisiblePosition.h"
36#include "core/rendering/RenderLayer.h"
37#include "core/rendering/compositing/CompositedSelectionBound.h"
38
39namespace blink {
40
41static inline RenderObject* rendererFromPosition(const Position& position)
42{
43    ASSERT(position.isNotNull());
44    Node* rendererNode = 0;
45    switch (position.anchorType()) {
46    case Position::PositionIsOffsetInAnchor:
47        rendererNode = position.computeNodeAfterPosition();
48        if (!rendererNode || !rendererNode->renderer())
49            rendererNode = position.anchorNode()->lastChild();
50        break;
51
52    case Position::PositionIsBeforeAnchor:
53    case Position::PositionIsAfterAnchor:
54        break;
55
56    case Position::PositionIsBeforeChildren:
57        rendererNode = position.anchorNode()->firstChild();
58        break;
59    case Position::PositionIsAfterChildren:
60        rendererNode = position.anchorNode()->lastChild();
61        break;
62    }
63    if (!rendererNode || !rendererNode->renderer())
64        rendererNode = position.anchorNode();
65    return rendererNode->renderer();
66}
67
68RenderedPosition::RenderedPosition(const VisiblePosition& position)
69    : m_renderer(0)
70    , m_inlineBox(0)
71    , m_offset(0)
72    , m_prevLeafChild(uncachedInlineBox())
73    , m_nextLeafChild(uncachedInlineBox())
74{
75    if (position.isNull())
76        return;
77    position.getInlineBoxAndOffset(m_inlineBox, m_offset);
78    if (m_inlineBox)
79        m_renderer = &m_inlineBox->renderer();
80    else
81        m_renderer = rendererFromPosition(position.deepEquivalent());
82}
83
84RenderedPosition::RenderedPosition(const Position& position, EAffinity affinity)
85    : m_renderer(0)
86    , m_inlineBox(0)
87    , m_offset(0)
88    , m_prevLeafChild(uncachedInlineBox())
89    , m_nextLeafChild(uncachedInlineBox())
90{
91    if (position.isNull())
92        return;
93    position.getInlineBoxAndOffset(affinity, m_inlineBox, m_offset);
94    if (m_inlineBox)
95        m_renderer = &m_inlineBox->renderer();
96    else
97        m_renderer = rendererFromPosition(position);
98}
99
100InlineBox* RenderedPosition::prevLeafChild() const
101{
102    if (m_prevLeafChild == uncachedInlineBox())
103        m_prevLeafChild = m_inlineBox->prevLeafChildIgnoringLineBreak();
104    return m_prevLeafChild;
105}
106
107InlineBox* RenderedPosition::nextLeafChild() const
108{
109    if (m_nextLeafChild == uncachedInlineBox())
110        m_nextLeafChild = m_inlineBox->nextLeafChildIgnoringLineBreak();
111    return m_nextLeafChild;
112}
113
114bool RenderedPosition::isEquivalent(const RenderedPosition& other) const
115{
116    return (m_renderer == other.m_renderer && m_inlineBox == other.m_inlineBox && m_offset == other.m_offset)
117        || (atLeftmostOffsetInBox() && other.atRightmostOffsetInBox() && prevLeafChild() == other.m_inlineBox)
118        || (atRightmostOffsetInBox() && other.atLeftmostOffsetInBox() && nextLeafChild() == other.m_inlineBox);
119}
120
121unsigned char RenderedPosition::bidiLevelOnLeft() const
122{
123    InlineBox* box = atLeftmostOffsetInBox() ? prevLeafChild() : m_inlineBox;
124    return box ? box->bidiLevel() : 0;
125}
126
127unsigned char RenderedPosition::bidiLevelOnRight() const
128{
129    InlineBox* box = atRightmostOffsetInBox() ? nextLeafChild() : m_inlineBox;
130    return box ? box->bidiLevel() : 0;
131}
132
133RenderedPosition RenderedPosition::leftBoundaryOfBidiRun(unsigned char bidiLevelOfRun)
134{
135    if (!m_inlineBox || bidiLevelOfRun > m_inlineBox->bidiLevel())
136        return RenderedPosition();
137
138    InlineBox* box = m_inlineBox;
139    do {
140        InlineBox* prev = box->prevLeafChildIgnoringLineBreak();
141        if (!prev || prev->bidiLevel() < bidiLevelOfRun)
142            return RenderedPosition(&box->renderer(), box, box->caretLeftmostOffset());
143        box = prev;
144    } while (box);
145
146    ASSERT_NOT_REACHED();
147    return RenderedPosition();
148}
149
150RenderedPosition RenderedPosition::rightBoundaryOfBidiRun(unsigned char bidiLevelOfRun)
151{
152    if (!m_inlineBox || bidiLevelOfRun > m_inlineBox->bidiLevel())
153        return RenderedPosition();
154
155    InlineBox* box = m_inlineBox;
156    do {
157        InlineBox* next = box->nextLeafChildIgnoringLineBreak();
158        if (!next || next->bidiLevel() < bidiLevelOfRun)
159            return RenderedPosition(&box->renderer(), box, box->caretRightmostOffset());
160        box = next;
161    } while (box);
162
163    ASSERT_NOT_REACHED();
164    return RenderedPosition();
165}
166
167bool RenderedPosition::atLeftBoundaryOfBidiRun(ShouldMatchBidiLevel shouldMatchBidiLevel, unsigned char bidiLevelOfRun) const
168{
169    if (!m_inlineBox)
170        return false;
171
172    if (atLeftmostOffsetInBox()) {
173        if (shouldMatchBidiLevel == IgnoreBidiLevel)
174            return !prevLeafChild() || prevLeafChild()->bidiLevel() < m_inlineBox->bidiLevel();
175        return m_inlineBox->bidiLevel() >= bidiLevelOfRun && (!prevLeafChild() || prevLeafChild()->bidiLevel() < bidiLevelOfRun);
176    }
177
178    if (atRightmostOffsetInBox()) {
179        if (shouldMatchBidiLevel == IgnoreBidiLevel)
180            return nextLeafChild() && m_inlineBox->bidiLevel() < nextLeafChild()->bidiLevel();
181        return nextLeafChild() && m_inlineBox->bidiLevel() < bidiLevelOfRun && nextLeafChild()->bidiLevel() >= bidiLevelOfRun;
182    }
183
184    return false;
185}
186
187bool RenderedPosition::atRightBoundaryOfBidiRun(ShouldMatchBidiLevel shouldMatchBidiLevel, unsigned char bidiLevelOfRun) const
188{
189    if (!m_inlineBox)
190        return false;
191
192    if (atRightmostOffsetInBox()) {
193        if (shouldMatchBidiLevel == IgnoreBidiLevel)
194            return !nextLeafChild() || nextLeafChild()->bidiLevel() < m_inlineBox->bidiLevel();
195        return m_inlineBox->bidiLevel() >= bidiLevelOfRun && (!nextLeafChild() || nextLeafChild()->bidiLevel() < bidiLevelOfRun);
196    }
197
198    if (atLeftmostOffsetInBox()) {
199        if (shouldMatchBidiLevel == IgnoreBidiLevel)
200            return prevLeafChild() && m_inlineBox->bidiLevel() < prevLeafChild()->bidiLevel();
201        return prevLeafChild() && m_inlineBox->bidiLevel() < bidiLevelOfRun && prevLeafChild()->bidiLevel() >= bidiLevelOfRun;
202    }
203
204    return false;
205}
206
207Position RenderedPosition::positionAtLeftBoundaryOfBiDiRun() const
208{
209    ASSERT(atLeftBoundaryOfBidiRun());
210
211    if (atLeftmostOffsetInBox())
212        return createLegacyEditingPosition(m_renderer->node(), m_offset);
213
214    return createLegacyEditingPosition(nextLeafChild()->renderer().node(), nextLeafChild()->caretLeftmostOffset());
215}
216
217Position RenderedPosition::positionAtRightBoundaryOfBiDiRun() const
218{
219    ASSERT(atRightBoundaryOfBidiRun());
220
221    if (atRightmostOffsetInBox())
222        return createLegacyEditingPosition(m_renderer->node(), m_offset);
223
224    return createLegacyEditingPosition(prevLeafChild()->renderer().node(), prevLeafChild()->caretRightmostOffset());
225}
226
227IntRect RenderedPosition::absoluteRect(LayoutUnit* extraWidthToEndOfLine) const
228{
229    if (isNull())
230        return IntRect();
231
232    IntRect localRect = pixelSnappedIntRect(m_renderer->localCaretRect(m_inlineBox, m_offset, extraWidthToEndOfLine));
233    return localRect == IntRect() ? IntRect() : m_renderer->localToAbsoluteQuad(FloatRect(localRect)).enclosingBoundingBox();
234}
235
236void RenderedPosition::positionInGraphicsLayerBacking(CompositedSelectionBound& bound) const
237{
238    bound.layer = nullptr;
239    bound.edgeTopInLayer = bound.edgeBottomInLayer = FloatPoint();
240
241    if (isNull())
242        return;
243
244    LayoutRect rect = m_renderer->localCaretRect(m_inlineBox, m_offset);
245    RenderLayer* layer = nullptr;
246    bound.edgeTopInLayer = m_renderer->localToInvalidationBackingPoint(rect.minXMinYCorner(), &layer);
247    bound.edgeBottomInLayer = m_renderer->localToInvalidationBackingPoint(rect.minXMaxYCorner(), nullptr);
248    bound.layer = layer->graphicsLayerBacking();
249}
250
251bool renderObjectContainsPosition(RenderObject* target, const Position& position)
252{
253    for (RenderObject* renderer = rendererFromPosition(position); renderer && renderer->node(); renderer = renderer->parent()) {
254        if (renderer == target)
255            return true;
256    }
257    return false;
258}
259
260};
261