FlexFormattingContextGeometry.cpp   [plain text]

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#include "config.h"
#include "FlexFormattingContext.h"

#if ENABLE(LAYOUT_FORMATTING_CONTEXT)

#include "FlexFormattingState.h"
#include "FormattingContext.h"
#include "LayoutContext.h"

namespace WebCore {
namespace Layout {

FormattingContext::IntrinsicWidthConstraints FlexFormattingContext::Geometry::intrinsicWidthConstraints(const ContainerBox& flexItem)
{
    auto fixedMarginBorderAndPadding = [&](auto& layoutBox) {
        auto& style = layoutBox.style();
        return fixedValue(style.marginStart()).valueOr(0)
            + LayoutUnit { style.borderLeftWidth() }
            + fixedValue(style.paddingLeft()).valueOr(0)
            + fixedValue(style.paddingRight()).valueOr(0)
            + LayoutUnit { style.borderRightWidth() }
            + fixedValue(style.marginEnd()).valueOr(0);
    };

    auto computedIntrinsicWidthConstraints = [&]() -> IntrinsicWidthConstraints {
        auto logicalWidth = flexItem.style().logicalWidth();
        // Minimum/maximum width can't be depending on the containing block's width.
        auto needsResolvedContainingBlockWidth = logicalWidth.isCalculated() || logicalWidth.isPercent() || logicalWidth.isRelative();
        if (needsResolvedContainingBlockWidth)
            return { };

        if (auto width = fixedValue(logicalWidth))
            return { *width, *width };

        ASSERT(flexItem.establishesFormattingContext());
        auto intrinsicWidthConstraints = LayoutContext::createFormattingContext(flexItem, layoutState())->computedIntrinsicWidthConstraints();
        if (logicalWidth.isMinContent())
            return { intrinsicWidthConstraints.minimum, intrinsicWidthConstraints.minimum };
        if (logicalWidth.isMaxContent())
            return { intrinsicWidthConstraints.maximum, intrinsicWidthConstraints.maximum };
        return intrinsicWidthConstraints;
    };
    auto intrinsicWidthConstraints = constrainByMinMaxWidth(flexItem, computedIntrinsicWidthConstraints());
    intrinsicWidthConstraints.expand(fixedMarginBorderAndPadding(flexItem));
    return intrinsicWidthConstraints;
}

}
}

#endif