2 files changed, 215 insertions, 0 deletions
diff --git a/include/cru/ui/host/LayoutPaintCycler.hpp b/include/cru/ui/host/LayoutPaintCycler.hpp
new file mode 100644
index 00000000..ed543afa
--- /dev/null
+++ b/include/cru/ui/host/LayoutPaintCycler.hpp
@@ -0,0 +1,39 @@
+#pragma once
+#include "../Base.hpp"
+
+#include "cru/platform/gui/UiApplication.hpp"
+
+#include <chrono>
+
+namespace cru::ui::host {
+class LayoutPaintCycler {
+ public:
+  explicit LayoutPaintCycler(WindowHost* host);
+
+  CRU_DELETE_COPY(LayoutPaintCycler)
+  CRU_DELETE_MOVE(LayoutPaintCycler)
+
+  ~LayoutPaintCycler();
+
+ public:
+  void InvalidateLayout();
+  void InvalidatePaint();
+
+  bool IsLayoutDirty() { return layout_dirty_; }
+
+ private:
+  void OnCycle();
+
+ private:
+  WindowHost* host_;
+
+  platform::gui::TimerAutoCanceler timer_canceler_;
+
+  bool layout_dirty_ = true;
+  bool paint_dirty_ = true;
+
+  std::chrono::steady_clock::time_point last_cycle_time_;
+  std::chrono::steady_clock::duration cycle_threshold_ =
+      std::chrono::milliseconds(1000) / 144;
+};
+}  // namespace cru::ui::host
diff --git a/include/cru/ui/host/WindowHost.hpp b/include/cru/ui/host/WindowHost.hpp
new file mode 100644
index 00000000..bd2f7c16
--- /dev/null
+++ b/include/cru/ui/host/WindowHost.hpp
@@ -0,0 +1,176 @@
+#pragma once
+#include "../Base.hpp"
+
+#include "../render/Base.hpp"
+#include "cru/common/Event.hpp"
+#include "cru/platform/gui/UiApplication.hpp"
+#include "cru/platform/gui/Window.hpp"
+
+#include <functional>
+#include <memory>
+#include <optional>
+
+namespace cru::ui::host {
+class LayoutPaintCycler;
+
+struct AfterLayoutEventArgs {};
+
+struct CreateWindowParams {
+  CreateWindowParams(platform::gui::INativeWindow* parent = nullptr,
+                     platform::gui::CreateWindowFlag flag = {})
+      : parent(parent), flag(flag) {}
+
+  platform::gui::INativeWindow* parent;
+  platform::gui::CreateWindowFlag flag;
+};
+
+// The bridge between control tree and native window.
+class WindowHost : public Object {
+  CRU_DEFINE_CLASS_LOG_TAG(u"cru::ui::host::WindowHost")
+
+ public:
+  WindowHost(controls::Control* root_control);
+
+  CRU_DELETE_COPY(WindowHost)
+  CRU_DELETE_MOVE(WindowHost)
+
+  ~WindowHost() override;
+
+ public:
+  platform::gui::INativeWindow* GetNativeWindow() { return native_window_; }
+
+  // Do nothing if native window is already created.
+  gsl::not_null<platform::gui::INativeWindow*> CreateNativeWindow(
+      CreateWindowParams create_window_params = {});
+
+  // Mark the layout as invalid, and arrange a re-layout later.
+  // This method could be called more than one times in a message cycle. But
+  // layout only takes place once.
+  void InvalidateLayout();
+
+  // Mark the paint as invalid, and arrange a re-paint later.
+  // This method could be called more than one times in a message cycle. But
+  // paint only takes place once.
+  void InvalidatePaint();
+
+  IEvent<AfterLayoutEventArgs>* AfterLayoutEvent() {
+    return &after_layout_event_;
+  }
+
+  void Relayout();
+  void Relayout(const Size& available_size);
+
+  void Repaint();
+
+  // Is layout is invalid, wait for relayout and then run the action. Otherwist
+  // run it right now.
+  void RunAfterLayoutStable(std::function<void()> action);
+
+  // If true, preferred size of root render object is set to window size when
+  // measure. Default is true.
+  bool IsLayoutPreferToFillWindow() const;
+  void SetLayoutPreferToFillWindow(bool value);
+
+  // Get current control that mouse hovers on. This ignores the mouse-capture
+  // control. Even when mouse is captured by another control, this function
+  // return the control under cursor. You can use `GetMouseCaptureControl` to
+  // get more info.
+  controls::Control* GetMouseHoverControl() const {
+    return mouse_hover_control_;
+  }
+
+  //*************** region: focus ***************
+
+  controls::Control* GetFocusControl();
+
+  void SetFocusControl(controls::Control* control);
+
+  //*************** region: focus ***************
+
+  // Pass nullptr to release capture. If mouse is already capture by a control,
+  // this capture will fail and return false. If control is identical to the
+  // capturing control, capture is not changed and this function will return
+  // true.
+  //
+  // When capturing control changes,
+  // appropriate event will be sent. If mouse is not on the capturing control
+  // and capture is released, mouse enter event will be sent to the mouse-hover
+  // control. If mouse is not on the capturing control and capture is set, mouse
+  // leave event will be sent to the mouse-hover control.
+  bool CaptureMouseFor(controls::Control* control);
+
+  // Return null if not captured.
+  controls::Control* GetMouseCaptureControl();
+
+  controls::Control* HitTest(const Point& point);
+
+  void UpdateCursor();
+
+  IEvent<platform::gui::INativeWindow*>* NativeWindowChangeEvent() {
+    return &native_window_change_event_;
+  }
+
+  // If window exist, return window actual size. Otherwise if saved rect exists,
+  // return it. Otherwise return 0.
+  Rect GetWindowRect();
+
+  void SetSavedWindowRect(std::optional<Rect> rect);
+
+  void SetWindowRect(const Rect& rect);
+
+ private:
+  //*************** region: native messages ***************
+  void OnNativeDestroy(platform::gui::INativeWindow* window, std::nullptr_t);
+  void OnNativePaint(platform::gui::INativeWindow* window, std::nullptr_t);
+  void OnNativeResize(platform::gui::INativeWindow* window, const Size& size);
+
+  void OnNativeFocus(platform::gui::INativeWindow* window,
+                     cru::platform::gui::FocusChangeType focus);
+
+  void OnNativeMouseEnterLeave(platform::gui::INativeWindow* window,
+                               cru::platform::gui::MouseEnterLeaveType enter);
+  void OnNativeMouseMove(platform::gui::INativeWindow* window,
+                         const Point& point);
+  void OnNativeMouseDown(platform::gui::INativeWindow* window,
+                         const platform::gui::NativeMouseButtonEventArgs& args);
+  void OnNativeMouseUp(platform::gui::INativeWindow* window,
+                       const platform::gui::NativeMouseButtonEventArgs& args);
+
+  void OnNativeKeyDown(platform::gui::INativeWindow* window,
+                       const platform::gui::NativeKeyEventArgs& args);
+  void OnNativeKeyUp(platform::gui::INativeWindow* window,
+                     const platform::gui::NativeKeyEventArgs& args);
+
+  //*************** region: event dispatcher helper ***************
+
+  void DispatchMouseHoverControlChangeEvent(controls::Control* old_control,
+                                            controls::Control* new_control,
+                                            const Point& point, bool no_leave,
+                                            bool no_enter);
+
+ private:
+  controls::Control* root_control_ = nullptr;
+  render::RenderObject* root_render_object_ = nullptr;
+
+  platform::gui::INativeWindow* native_window_ = nullptr;
+
+  std::unique_ptr<LayoutPaintCycler> layout_paint_cycler_;
+
+  Event<AfterLayoutEventArgs> after_layout_event_;
+  std::vector<std::function<void()> > after_layout_stable_action_;
+
+  std::vector<EventRevokerGuard> event_revoker_guards_;
+
+  controls::Control* mouse_hover_control_ = nullptr;
+
+  controls::Control* focus_control_;
+
+  controls::Control* mouse_captured_control_ = nullptr;
+
+  bool layout_prefer_to_fill_window_ = true;
+
+  Event<platform::gui::INativeWindow*> native_window_change_event_;
+
+  std::optional<Rect> saved_rect_;
+};
+}  // namespace cru::ui::host