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/*
* Copyright (C) 2011 Google 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:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT
* OWNER OR 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 "FlexibleBoxAlgorithm.h"
#include "RenderBox.h"
#include "RenderStyleInlines.h"
namespace WebCore {
FlexItem::FlexItem(RenderBox& box, LayoutUnit flexBaseContentSize, LayoutUnit mainAxisBorderAndPadding, LayoutUnit mainAxisMargin, std::pair<LayoutUnit, LayoutUnit> minMaxSizes, bool everHadLayout)
: box(box)
, flexBaseContentSize(flexBaseContentSize)
, mainAxisBorderAndPadding(mainAxisBorderAndPadding)
, mainAxisMargin(mainAxisMargin)
, minMaxSizes(minMaxSizes)
, hypotheticalMainContentSize(constrainSizeByMinMax(flexBaseContentSize))
, frozen(false)
, everHadLayout(everHadLayout)
{
ASSERT(!box.isOutOfFlowPositioned());
}
FlexLayoutAlgorithm::FlexLayoutAlgorithm(RenderFlexibleBox& flexbox, LayoutUnit lineBreakLength, const Vector<FlexItem>& allItems, LayoutUnit gapBetweenItems, LayoutUnit gapBetweenLines)
: m_flexbox(flexbox)
, m_lineBreakLength(lineBreakLength)
, m_allItems(allItems)
, m_gapBetweenItems(gapBetweenItems)
, m_gapBetweenLines(gapBetweenLines)
{
}
bool FlexLayoutAlgorithm::canFitItemWithTrimmedMarginEnd(const FlexItem& item, LayoutUnit sumHypotheticalMainSize) const
{
auto marginTrim = m_flexbox.style().marginTrim();
if ((m_flexbox.isHorizontalFlow() && marginTrim.contains(MarginTrimType::InlineEnd)) || (m_flexbox.isColumnFlow() && marginTrim.contains(MarginTrimType::BlockEnd)))
return sumHypotheticalMainSize + item.hypotheticalMainAxisMarginBoxSize() - m_flexbox.flowAwareMarginEndForChild(item.box) <= m_lineBreakLength;
return false;
}
void FlexLayoutAlgorithm::removeMarginEndFromFlexSizes(FlexItem& flexItem, LayoutUnit& sumFlexBaseSize, LayoutUnit& sumHypotheticalMainSize) const
{
LayoutUnit margin;
if (m_flexbox.isHorizontalFlow())
margin = flexItem.box.marginEnd(&m_flexbox.style());
else
margin = flexItem.box.marginAfter(&m_flexbox.style());
sumFlexBaseSize -= margin;
sumHypotheticalMainSize -= margin;
}
bool FlexLayoutAlgorithm::computeNextFlexLine(size_t& nextIndex, Vector<FlexItem>& lineItems, LayoutUnit& sumFlexBaseSize, double& totalFlexGrow, double& totalFlexShrink, double& totalWeightedFlexShrink, LayoutUnit& sumHypotheticalMainSize)
{
lineItems.clear();
sumFlexBaseSize = 0_lu;
totalFlexGrow = totalFlexShrink = totalWeightedFlexShrink = 0;
sumHypotheticalMainSize = 0_lu;
// Trim main axis margin for item at the start of the flex line
if (nextIndex < m_allItems.size() && m_flexbox.shouldTrimMainAxisMarginStart())
m_flexbox.trimMainAxisMarginStart(m_allItems[nextIndex]);
for (; nextIndex < m_allItems.size(); ++nextIndex) {
const auto& flexItem = m_allItems[nextIndex];
ASSERT(!flexItem.box.isOutOfFlowPositioned());
if (isMultiline() && (sumHypotheticalMainSize + flexItem.hypotheticalMainAxisMarginBoxSize() > m_lineBreakLength && !canFitItemWithTrimmedMarginEnd(flexItem, sumHypotheticalMainSize)) && !lineItems.isEmpty())
break;
lineItems.append(flexItem);
sumFlexBaseSize += flexItem.flexBaseMarginBoxSize() + m_gapBetweenItems;
totalFlexGrow += flexItem.box.style().flexGrow();
totalFlexShrink += flexItem.box.style().flexShrink();
totalWeightedFlexShrink += flexItem.box.style().flexShrink() * flexItem.flexBaseContentSize;
sumHypotheticalMainSize += flexItem.hypotheticalMainAxisMarginBoxSize() + m_gapBetweenItems;
}
if (!lineItems.isEmpty()) {
// We added a gap after every item but there shouldn't be one after the last item, so subtract it here. Note that
// sums might be negative here due to negative margins in flex items.
sumHypotheticalMainSize -= m_gapBetweenItems;
sumFlexBaseSize -= m_gapBetweenItems;
}
ASSERT(lineItems.size() > 0 || nextIndex == m_allItems.size());
// Trim main axis margin for item at the end of the flex line
if (lineItems.size() && m_flexbox.shouldTrimMainAxisMarginEnd()) {
auto lastItem = lineItems.last();
removeMarginEndFromFlexSizes(lastItem, sumFlexBaseSize, sumHypotheticalMainSize);
m_flexbox.trimMainAxisMarginEnd(lastItem);
}
return lineItems.size() > 0;
}
LayoutUnit FlexItem::constrainSizeByMinMax(const LayoutUnit size) const
{
return std::max(minMaxSizes.first, std::min(size, minMaxSizes.second));
}
} // namespace WebCore
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