third_party/WebKit/Source/core/layout/LayoutRuby.cpp

   1 /*
   2  * Copyright (C) 2009 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
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   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,
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  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
  33 #include "core/layout/LayoutRuby.h"
  34
  35 #include "core/frame/UseCounter.h"
  36 #include "core/layout/LayoutRubyRun.h"
  37
  38 namespace blink {
  39
  40 // === generic helper functions to avoid excessive code duplication ===
  41
  42 static LayoutRubyRun* lastRubyRun(const LayoutObject* ruby)
  43 {
  44     LayoutObject* child = ruby->slowLastChild();
  45     ASSERT(!child || child->isRubyRun());
  46     return toLayoutRubyRun(child);
  47 }
  48
  49 static inline LayoutRubyRun* findRubyRunParent(LayoutObject* child)
  50 {
  51     while (child && !child->isRubyRun())
  52         child = child->parent();
  53     return toLayoutRubyRun(child);
  54 }
  55
  56 // === ruby as inline object ===
  57
  58 LayoutRubyAsInline::LayoutRubyAsInline(Element* element)
  59     : LayoutInline(element)
  60 {
  61     UseCounter::count(document(), UseCounter::RenderRuby);
  62 }
  63
  64 LayoutRubyAsInline::~LayoutRubyAsInline()
  65 {
  66 }
  67
  68 void LayoutRubyAsInline::styleDidChange(StyleDifference diff, const ComputedStyle* oldStyle)
  69 {
  70     LayoutInline::styleDidChange(diff, oldStyle);
  71     propagateStyleToAnonymousChildren();
  72 }
  73
  74 void LayoutRubyAsInline::addChild(LayoutObject* child, LayoutObject* beforeChild)
  75 {
  76     // If the child is a ruby run, just add it normally.
  77     if (child->isRubyRun()) {
  78         LayoutInline::addChild(child, beforeChild);
  79         return;
  80     }
  81
  82     if (beforeChild) {
  83         // insert child into run
  84         LayoutObject* run = beforeChild;
  85         while (run && !run->isRubyRun())
  86             run = run->parent();
  87         if (run) {
  88             if (beforeChild == run)
  89                 beforeChild = toLayoutRubyRun(beforeChild)->firstChild();
  90             ASSERT(!beforeChild || beforeChild->isDescendantOf(run));
  91             run->addChild(child, beforeChild);
  92             return;
  93         }
  94         ASSERT_NOT_REACHED(); // beforeChild should always have a run as parent!
  95         // Emergency fallback: fall through and just append.
  96     }
  97
  98     // If the new child would be appended, try to add the child to the previous run
  99     // if possible, or create a new run otherwise.
 100     // (The LayoutRubyRun object will handle the details)
 101     LayoutRubyRun* lastRun = lastRubyRun(this);
 102     if (!lastRun || lastRun->hasRubyText()) {
 103         lastRun = LayoutRubyRun::staticCreateRubyRun(this);
 104         LayoutInline::addChild(lastRun, beforeChild);
 105     }
 106     lastRun->addChild(child);
 107 }
 108
 109 void LayoutRubyAsInline::removeChild(LayoutObject* child)
 110 {
 111     // If the child's parent is *this (must be a ruby run), just use the normal remove method.
 112     if (child->parent() == this) {
 113         ASSERT(child->isRubyRun());
 114         LayoutInline::removeChild(child);
 115         return;
 116     }
 117
 118     // Otherwise find the containing run and remove it from there.
 119     LayoutRubyRun* run = findRubyRunParent(child);
 120     ASSERT(run);
 121     run->removeChild(child);
 122 }
 123
 124 // === ruby as block object ===
 125
 126 LayoutRubyAsBlock::LayoutRubyAsBlock(Element* element)
 127     : LayoutBlockFlow(element)
 128 {
 129     UseCounter::count(document(), UseCounter::RenderRuby);
 130 }
 131
 132 LayoutRubyAsBlock::~LayoutRubyAsBlock()
 133 {
 134 }
 135
 136 void LayoutRubyAsBlock::styleDidChange(StyleDifference diff, const ComputedStyle* oldStyle)
 137 {
 138     LayoutBlockFlow::styleDidChange(diff, oldStyle);
 139     propagateStyleToAnonymousChildren();
 140 }
 141
 142 void LayoutRubyAsBlock::addChild(LayoutObject* child, LayoutObject* beforeChild)
 143 {
 144     // If the child is a ruby run, just add it normally.
 145     if (child->isRubyRun()) {
 146         LayoutBlockFlow::addChild(child, beforeChild);
 147         return;
 148     }
 149
 150     if (beforeChild) {
 151         // insert child into run
 152         LayoutObject* run = beforeChild;
 153         while (run && !run->isRubyRun())
 154             run = run->parent();
 155         if (run) {
 156             if (beforeChild == run)
 157                 beforeChild = toLayoutRubyRun(beforeChild)->firstChild();
 158             ASSERT(!beforeChild || beforeChild->isDescendantOf(run));
 159             run->addChild(child, beforeChild);
 160             return;
 161         }
 162         ASSERT_NOT_REACHED(); // beforeChild should always have a run as parent!
 163         // Emergency fallback: fall through and just append.
 164     }
 165
 166     // If the new child would be appended, try to add the child to the previous run
 167     // if possible, or create a new run otherwise.
 168     // (The LayoutRubyRun object will handle the details)
 169     LayoutRubyRun* lastRun = lastRubyRun(this);
 170     if (!lastRun || lastRun->hasRubyText()) {
 171         lastRun = LayoutRubyRun::staticCreateRubyRun(this);
 172         LayoutBlockFlow::addChild(lastRun, beforeChild);
 173     }
 174     lastRun->addChild(child);
 175 }
 176
 177 void LayoutRubyAsBlock::removeChild(LayoutObject* child)
 178 {
 179     // If the child's parent is *this (must be a ruby run), just use the normal remove method.
 180     if (child->parent() == this) {
 181         ASSERT(child->isRubyRun());
 182         LayoutBlockFlow::removeChild(child);
 183         return;
 184     }
 185
 186     // Otherwise find the containing run and remove it from there.
 187     LayoutRubyRun* run = findRubyRunParent(child);
 188     ASSERT(run);
 189     run->removeChild(child);
 190 }
 191
 192 } // namespace blink