1 files changed, 161 insertions, 0 deletions
diff --git a/src/ui/controls/scroll_control.hpp b/src/ui/controls/scroll_control.hpp
new file mode 100644
index 00000000..0541a010
--- /dev/null
+++ b/src/ui/controls/scroll_control.hpp
@@ -0,0 +1,161 @@
+#pragma once
+
+// ReSharper disable once CppUnusedIncludeDirective
+#include "pre.hpp"
+
+#include <optional>
+#include <initializer_list>
+
+#include "ui/control.hpp"
+
+namespace cru::ui::controls
+{
+    // Done: OnMeasureContent
+    // Done: OnLayoutContent
+    // Done: HitTest(no need)
+    // Done: Draw(no need)
+    // Done: API
+    // Done: ScrollBar
+    // Done: MouseEvent
+    class ScrollControl : public Control
+    {
+    private:
+        struct ScrollBarInfo
+        {
+            Rect border = Rect();
+            Rect bar = Rect();
+        };
+
+        enum class Orientation
+        {
+            Horizontal,
+            Vertical
+        };
+
+    public:
+        enum class ScrollBarVisibility
+        {
+            None,
+            Auto,
+            Always
+        };
+
+        static ScrollControl* Create(const std::initializer_list<Control*>& children = std::initializer_list<Control*>{})
+        {
+            const auto control = new ScrollControl(true);
+            for (auto child : children)
+                control->AddChild(child);
+            return control;
+        }
+
+        static constexpr auto control_type = L"ScrollControl";
+
+    protected:
+        explicit ScrollControl(bool container);
+    public:
+        ScrollControl(const ScrollControl& other) = delete;
+        ScrollControl(ScrollControl&& other) = delete;
+        ScrollControl& operator=(const ScrollControl& other) = delete;
+        ScrollControl& operator=(ScrollControl&& other) = delete;
+        ~ScrollControl() override;
+
+        StringView GetControlType() const override final;
+
+        bool IsHorizontalScrollEnabled() const
+        {
+            return horizontal_scroll_enabled_;
+        }
+
+        void SetHorizontalScrollEnabled(bool enable);
+
+        bool IsVerticalScrollEnabled() const
+        {
+            return vertical_scroll_enabled_;
+        }
+
+        void SetVerticalScrollEnabled(bool enable);
+
+
+        ScrollBarVisibility GetHorizontalScrollBarVisibility() const
+        {
+            return horizontal_scroll_bar_visibility_;
+        }
+
+        void SetHorizontalScrollBarVisibility(ScrollBarVisibility visibility);
+
+        ScrollBarVisibility GetVerticalScrollBarVisibility() const
+        {
+            return vertical_scroll_bar_visibility_;
+        }
+
+        void SetVerticalScrollBarVisibility(ScrollBarVisibility visibility);
+
+        float GetViewWidth() const
+        {
+            return view_width_;
+        }
+
+        float GetViewHeight() const
+        {
+            return view_height_;
+        }
+
+        float GetScrollOffsetX() const
+        {
+            return offset_x_;
+        }
+
+        float GetScrollOffsetY() const
+        {
+            return offset_y_;
+        }
+
+        // nullopt for not set. value is auto-coerced.
+        void SetScrollOffset(std::optional<float> x, std::optional<float> y);
+
+    protected:
+        void SetViewWidth(float length);
+        void SetViewHeight(float length);
+
+        Size OnMeasureContent(const Size& available_size) override final;
+        void OnLayoutContent(const Rect& rect) override final;
+
+        void AfterLayoutSelf() override;
+
+        void OnDrawForeground(ID2D1DeviceContext* device_context) override;
+
+        void OnMouseDownCore(events::MouseButtonEventArgs& args) override final;
+        void OnMouseMoveCore(events::MouseEventArgs& args) override final;
+        void OnMouseUpCore(events::MouseButtonEventArgs& args) override final;
+
+        void OnMouseWheelCore(events::MouseWheelEventArgs& args) override;
+
+    private:
+        void CoerceAndSetOffsets(float offset_x, float offset_y, bool update_children = true);
+        void UpdateScrollBarVisibility();
+        void UpdateScrollBarBorderInfo();
+        void UpdateScrollBarBarInfo();
+
+    private:
+        bool horizontal_scroll_enabled_ = true;
+        bool vertical_scroll_enabled_ = true;
+
+        ScrollBarVisibility horizontal_scroll_bar_visibility_ = ScrollBarVisibility::Auto;
+        ScrollBarVisibility vertical_scroll_bar_visibility_ = ScrollBarVisibility::Auto;
+
+        bool is_horizontal_scroll_bar_visible_ = false;
+        bool is_vertical_scroll_bar_visible_ = false;
+
+        float offset_x_ = 0.0f;
+        float offset_y_ = 0.0f;
+
+        float view_width_ = 0.0f;
+        float view_height_ = 0.0f;
+
+        ScrollBarInfo horizontal_bar_info_;
+        ScrollBarInfo vertical_bar_info_;
+
+        std::optional<Orientation> is_pressing_scroll_bar_ = std::nullopt;
+        float pressing_delta_ = 0.0f;
+    };
+}