Align.h

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/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
 
#pragma once
 
#include <yoga/Yoga.h>
 
#include <yoga/algorithm/FlexDirection.h>
#include <yoga/node/Node.h>
 
namespace facebook::yoga {
 
inline Align resolveChildAlignment(
    const yoga::Node* node,
    const yoga::Node* child) {
  const Align align = child->style().alignSelf() == Align::Auto
      ? node->style().alignItems()
      : child->style().alignSelf();
 
  if (node->style().display() == Display::Flex && align == Align::Baseline &&
      isColumn(node->style().flexDirection())) {
    return Align::FlexStart;
  }
 
  return align;
}
 
inline Justify resolveChildJustification(
    const yoga::Node* node,
    const yoga::Node* child) {
  return child->style().justifySelf() == Justify::Auto
      ? node->style().justifyItems()
      : child->style().justifySelf();
}
 
constexpr Align fallbackAlignment(Align align) {
  switch (align) {
      // Fallback to flex-start
    case Align::SpaceBetween:
    case Align::Stretch:
      return Align::FlexStart;
 
    // Fallback to safe center. TODO (T208209388): This should be aligned to
    // Start instead of FlexStart (for row-reverse containers)
    case Align::SpaceAround:
    case Align::SpaceEvenly:
      return Align::FlexStart;
    default:
      return align;
  }
}
 
constexpr Justify fallbackAlignment(Justify align) {
  switch (align) {
      // Fallback to flex-start
    case Justify::SpaceBetween:
      // TODO: Support `justify-content: stretch`
      // case Justify::Stretch:
      return Justify::FlexStart;
 
    // Fallback to safe center. TODO (T208209388): This should be aligned to
    // Start instead of FlexStart (for row-reverse containers)
    case Justify::SpaceAround:
    case Justify::SpaceEvenly:
      return Justify::FlexStart;
    default:
      return align;
  }
}
 
} // namespace facebook::yoga