1 files changed, 57 insertions, 0 deletions
diff --git a/include/cru/ui/render/flex_layout_render_object.hpp b/include/cru/ui/render/flex_layout_render_object.hpp
new file mode 100644
index 00000000..278bf8c2
--- /dev/null
+++ b/include/cru/ui/render/flex_layout_render_object.hpp
@@ -0,0 +1,57 @@
+#pragma once
+#include "render_object.hpp"
+
+#include <optional>
+
+namespace cru::ui::render {
+enum class FlexDirection {
+  Horizontal,
+  HorizontalReverse,
+  Vertical,
+  VertivalReverse
+};
+
+enum class Alignment { Start, End, Center };
+
+struct FlexChildLayoutData {
+  std::optional<float> flex_basis;  // nullopt stands for content
+  float flex_grow = 0;
+  float flex_shrink = 0;
+  Alignment alignment = Alignment::Center;
+};
+
+class FlexLayoutRenderObject : public RenderObject {
+ public:
+  FlexLayoutRenderObject() = default;
+  FlexLayoutRenderObject(const FlexLayoutRenderObject& other) = delete;
+  FlexLayoutRenderObject& operator=(const FlexLayoutRenderObject& other) =
+      delete;
+  FlexLayoutRenderObject(FlexLayoutRenderObject&& other) = delete;
+  FlexLayoutRenderObject& operator=(FlexLayoutRenderObject&& other) = delete;
+  ~FlexLayoutRenderObject() override = default;
+
+  FlexDirection GetFlexDirection() const { return direction_; }
+  void SetFlexDirection(FlexDirection direction) { direction_ = direction; }
+
+  Alignment GetContentMainAlign() const { return content_main_align_; }
+  void SetContentMainAlign(Alignment align) { content_main_align_ = align; }
+
+  FlexChildLayoutData* GetChildLayoutData(int position);
+
+  void Draw(platform::Painter* painter) override;
+
+  RenderObject* HitTest(const Point& point) override;
+
+ protected:
+  void OnAddChild(RenderObject* new_child, int position) override;
+  void OnRemoveChild(RenderObject* removed_child, int position) override;
+
+  Size OnMeasureContent(const Size& available_size) override;
+  void OnLayoutContent(const Rect& content_rect) override;
+
+ private:
+  FlexDirection direction_ = FlexDirection::Horizontal;
+  Alignment content_main_align_ = Alignment::Start;
+  std::vector<FlexChildLayoutData> child_layout_data_{};
+};
+}  // namespace cru::ui::render