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/*
* Copyright (C) 2019 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "InlineLineLayout.h"
#if ENABLE(LAYOUT_FORMATTING_CONTEXT)
#include "LayoutBox.h"
#include "TextUtil.h"
namespace WebCore {
namespace Layout {
static LayoutUnit inlineItemWidth(const FormattingContext& formattingContext, const InlineItem& inlineItem, LayoutUnit contentLogicalLeft)
{
if (inlineItem.isLineBreak())
return 0;
if (is<InlineTextItem>(inlineItem)) {
auto& inlineTextItem = downcast<InlineTextItem>(inlineItem);
auto end = inlineTextItem.isCollapsed() ? inlineTextItem.start() + 1 : inlineTextItem.end();
return TextUtil::width(inlineTextItem.layoutBox(), inlineTextItem.start(), end, contentLogicalLeft);
}
auto& layoutBox = inlineItem.layoutBox();
auto& boxGeometry = formattingContext.geometryForBox(layoutBox);
if (layoutBox.isFloatingPositioned())
return boxGeometry.marginBoxWidth();
if (layoutBox.replaced())
return boxGeometry.width();
if (inlineItem.isContainerStart())
return boxGeometry.marginStart() + boxGeometry.borderLeft() + boxGeometry.paddingLeft().valueOr(0);
if (inlineItem.isContainerEnd())
return boxGeometry.marginEnd() + boxGeometry.borderRight() + boxGeometry.paddingRight().valueOr(0);
// Non-replaced inline box (e.g. inline-block)
return boxGeometry.width();
}
LineLayout::LineInput::LineInput(const Line::InitialConstraints& initialLineConstraints, TextAlignMode horizontalAlignment, IndexAndRange firstToProcess, const InlineItems& inlineItems)
: initialConstraints(initialLineConstraints)
, horizontalAlignment(horizontalAlignment)
, firstInlineItem(firstToProcess)
, inlineItems(inlineItems)
{
}
LineLayout::LineInput::LineInput(const Line::InitialConstraints& initialLineConstraints, IndexAndRange firstToProcess, const InlineItems& inlineItems)
: initialConstraints(initialLineConstraints)
, skipAlignment(Line::SkipAlignment::Yes)
, firstInlineItem(firstToProcess)
, inlineItems(inlineItems)
{
}
void LineLayout::UncommittedContent::add(const InlineItem& inlineItem, LayoutUnit logicalWidth)
{
m_uncommittedRuns.append({ inlineItem, logicalWidth });
m_width += logicalWidth;
}
void LineLayout::UncommittedContent::reset()
{
m_uncommittedRuns.clear();
m_width = 0;
}
LineLayout::LineLayout(const InlineFormattingContext& inlineFormattingContext, const LineInput& lineInput)
: m_inlineFormattingContext(inlineFormattingContext)
, m_lineInput(lineInput)
, m_line(inlineFormattingContext, lineInput.initialConstraints, lineInput.horizontalAlignment, lineInput.skipAlignment)
, m_lineHasIntrusiveFloat(lineInput.initialConstraints.lineIsConstrainedByFloat)
{
}
LineLayout::LineContent LineLayout::layout()
{
// Iterate through the inline content and place the inline boxes on the current line.
// Start with the partial text from the previous line.
auto firstInlineItem = m_lineInput.firstInlineItem;
unsigned firstNonPartialIndex = firstInlineItem.index;
if (firstInlineItem.partialContext) {
// Handle partial inline item (split text from the previous line).
auto& originalTextItem = m_lineInput.inlineItems[firstInlineItem.index];
RELEASE_ASSERT(originalTextItem->isText());
auto textRange = *firstInlineItem.partialContext;
// Construct a partial leading inline item.
ASSERT(!m_leadingPartialInlineTextItem);
m_leadingPartialInlineTextItem = downcast<InlineTextItem>(*originalTextItem).split(textRange.start, textRange.length);
if (placeInlineItem(*m_leadingPartialInlineTextItem) == IsEndOfLine::Yes)
return close();
++firstNonPartialIndex;
}
for (auto inlineItemIndex = firstNonPartialIndex; inlineItemIndex < m_lineInput.inlineItems.size(); ++inlineItemIndex) {
if (placeInlineItem(*m_lineInput.inlineItems[inlineItemIndex]) == IsEndOfLine::Yes)
return close();
}
commitPendingContent();
return close();
}
void LineLayout::commitPendingContent()
{
if (m_uncommittedContent.isEmpty())
return;
m_committedInlineItemCount += m_uncommittedContent.size();
for (auto& uncommittedRun : m_uncommittedContent.runs())
m_line.append(uncommittedRun.inlineItem, uncommittedRun.logicalWidth);
m_uncommittedContent.reset();
}
LineLayout::LineContent LineLayout::close()
{
ASSERT(m_committedInlineItemCount || m_lineHasIntrusiveFloat);
if (!m_committedInlineItemCount)
return LineContent { WTF::nullopt, WTFMove(m_floats), m_line.close(), m_line.lineBox() };
auto lastInlineItemIndex = m_lineInput.firstInlineItem.index + m_committedInlineItemCount - 1;
Optional<IndexAndRange::Range> partialContext;
if (m_trailingPartialInlineTextItem)
partialContext = IndexAndRange::Range { m_trailingPartialInlineTextItem->start(), m_trailingPartialInlineTextItem->length() };
auto lastCommitedItem = IndexAndRange { lastInlineItemIndex, partialContext };
return LineContent { lastCommitedItem, WTFMove(m_floats), m_line.close(), m_line.lineBox() };
}
LineLayout::IsEndOfLine LineLayout::placeInlineItem(const InlineItem& inlineItem)
{
auto availableWidth = m_line.availableWidth() - m_uncommittedContent.width();
auto currentLogicalRight = m_line.lineBox().logicalRight() + m_uncommittedContent.width();
auto itemLogicalWidth = inlineItemWidth(formattingContext(), inlineItem, currentLogicalRight);
// FIXME: Ensure LineContext::trimmableWidth includes uncommitted content if needed.
auto lineIsConsideredEmpty = !m_line.hasContent() && !m_lineHasIntrusiveFloat;
auto breakingContext = m_lineBreaker.breakingContext(inlineItem, itemLogicalWidth, { availableWidth, currentLogicalRight, m_line.trailingTrimmableWidth(), lineIsConsideredEmpty });
if (breakingContext.isAtBreakingOpportunity)
commitPendingContent();
// Content does not fit the current line.
if (breakingContext.breakingBehavior == LineBreaker::BreakingBehavior::Wrap)
return IsEndOfLine::Yes;
// Partial content stays on the current line.
if (breakingContext.breakingBehavior == LineBreaker::BreakingBehavior::Split) {
ASSERT(inlineItem.isText());
auto& inlineTextItem = downcast<InlineTextItem>(inlineItem);
auto splitData = TextUtil::split(inlineTextItem.layoutBox(), inlineTextItem.start(), inlineTextItem.length(), itemLogicalWidth, availableWidth, currentLogicalRight);
// Construct a partial trailing inline item.
ASSERT(!m_trailingPartialInlineTextItem);
m_trailingPartialInlineTextItem = inlineTextItem.split(splitData.start, splitData.length);
m_uncommittedContent.add(*m_trailingPartialInlineTextItem, splitData.logicalWidth);
commitPendingContent();
return IsEndOfLine::Yes;
}
ASSERT(breakingContext.breakingBehavior == LineBreaker::BreakingBehavior::Keep);
if (inlineItem.isFloat()) {
auto& floatBox = inlineItem.layoutBox();
// Shrink available space for current line and move existing inline runs.
auto floatBoxWidth = formattingContext().geometryForBox(floatBox).marginBoxWidth();
floatBox.isLeftFloatingPositioned() ? m_line.moveLogicalLeft(floatBoxWidth) : m_line.moveLogicalRight(floatBoxWidth);
m_floats.append(makeWeakPtr(inlineItem));
++m_committedInlineItemCount;
m_lineHasIntrusiveFloat = true;
return IsEndOfLine::No;
}
m_uncommittedContent.add(inlineItem, itemLogicalWidth);
if (breakingContext.isAtBreakingOpportunity)
commitPendingContent();
return inlineItem.isHardLineBreak() ? IsEndOfLine::Yes : IsEndOfLine::No;
}
}
}
#endif