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

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#include "core/layout/LayoutRubyBase.h"

namespace blink {

LayoutRubyBase::LayoutRubyBase() : LayoutBlockFlow(nullptr) {
  setInline(false);
}

LayoutRubyBase::~LayoutRubyBase() {}

LayoutRubyBase* LayoutRubyBase::createAnonymous(Document* document) {
  LayoutRubyBase* layoutObject = new LayoutRubyBase();
  layoutObject->setDocumentForAnonymous(document);
  return layoutObject;
}

bool LayoutRubyBase::isChildAllowed(LayoutObject* child,
                                    const ComputedStyle&) const {
  return child->isInline();
}

void LayoutRubyBase::moveChildren(LayoutRubyBase* toBase,
                                  LayoutObject* beforeChild) {
  // This function removes all children that are before (!) beforeChild
  // and appends them to toBase.
  DCHECK(toBase);
  // Callers should have handled the percent height descendant map.
  ASSERT(!hasPercentHeightDescendants());

  if (beforeChild && beforeChild->parent() != this)
    beforeChild = splitAnonymousBoxesAroundChild(beforeChild);

  if (childrenInline())
    moveInlineChildren(toBase, beforeChild);
  else
    moveBlockChildren(toBase, beforeChild);

  setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation(
      LayoutInvalidationReason::Unknown);
  toBase->setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation(
      LayoutInvalidationReason::Unknown);
}

void LayoutRubyBase::moveInlineChildren(LayoutRubyBase* toBase,
                                        LayoutObject* beforeChild) {
  ASSERT(childrenInline());
  DCHECK(toBase);

  if (!firstChild())
    return;

  LayoutBlock* toBlock;
  if (toBase->childrenInline()) {
    // The standard and easy case: move the children into the target base
    toBlock = toBase;
  } else {
    // We need to wrap the inline objects into an anonymous block.
    // If toBase has a suitable block, we re-use it, otherwise create a new one.
    LayoutObject* lastChild = toBase->lastChild();
    if (lastChild && lastChild->isAnonymousBlock() &&
        lastChild->childrenInline()) {
      toBlock = toLayoutBlock(lastChild);
    } else {
      toBlock = toBase->createAnonymousBlock();
      toBase->children()->appendChildNode(toBase, toBlock);
    }
  }
  // Move our inline children into the target block we determined above.
  moveChildrenTo(toBlock, firstChild(), beforeChild);
}

void LayoutRubyBase::moveBlockChildren(LayoutRubyBase* toBase,
                                       LayoutObject* beforeChild) {
  ASSERT(!childrenInline());
  DCHECK(toBase);

  if (!firstChild())
    return;

  if (toBase->childrenInline())
    toBase->makeChildrenNonInline();

  // If an anonymous block would be put next to another such block, then merge
  // those.
  LayoutObject* firstChildHere = firstChild();
  LayoutObject* lastChildThere = toBase->lastChild();
  if (firstChildHere->isAnonymousBlock() && firstChildHere->childrenInline() &&
      lastChildThere && lastChildThere->isAnonymousBlock() &&
      lastChildThere->childrenInline()) {
    LayoutBlockFlow* anonBlockHere = toLayoutBlockFlow(firstChildHere);
    LayoutBlockFlow* anonBlockThere = toLayoutBlockFlow(lastChildThere);
    anonBlockHere->moveAllChildrenTo(anonBlockThere,
                                     anonBlockThere->children());
    anonBlockHere->deleteLineBoxTree();
    anonBlockHere->destroy();
  }
  // Move all remaining children normally.
  moveChildrenTo(toBase, firstChild(), beforeChild);
}

ETextAlign LayoutRubyBase::textAlignmentForLine(
    bool /* endsWithSoftBreak */) const {
  return JUSTIFY;
}

void LayoutRubyBase::adjustInlineDirectionLineBounds(
    unsigned expansionOpportunityCount,
    LayoutUnit& logicalLeft,
    LayoutUnit& logicalWidth) const {
  int maxPreferredLogicalWidth = this->maxPreferredLogicalWidth().toInt();
  if (maxPreferredLogicalWidth >= logicalWidth)
    return;

  unsigned maxCount = static_cast<unsigned>(LayoutUnit::max().floor());
  if (expansionOpportunityCount > maxCount)
    expansionOpportunityCount = maxCount;

  // Inset the ruby base by half the inter-ideograph expansion amount.
  LayoutUnit inset = (logicalWidth - maxPreferredLogicalWidth) /
                     (expansionOpportunityCount + 1);

  logicalLeft += inset / 2;
  logicalWidth -= inset;
}

}  // namespace blink