1 files changed, 32 insertions, 0 deletions
diff --git a/src/ui/click_detector.cpp b/src/ui/click_detector.cpp
new file mode 100644
index 00000000..1442b885
--- /dev/null
+++ b/src/ui/click_detector.cpp
@@ -0,0 +1,32 @@
+#include "cru/ui/click_detector.hpp"
+
+#include <cassert>
+#include <optional>
+
+namespace cru::ui {
+ClickDetector::ClickDetector(Control* control) {
+  assert(control);
+  control_ = control;
+
+  event_rovoker_guards_.push_front(
+      EventRevokerGuard(control->MouseDownEvent()->Direct()->AddHandler(
+          [this, control](event::MouseButtonEventArgs& args) {
+            if (!control->CaptureMouse()) return;  // capture failed
+            FromButton(args.GetMouseButton()) =
+                args.GetPoint();  // save mouse down point
+          })));
+
+  event_rovoker_guards_.push_front(
+      EventRevokerGuard(control->MouseUpEvent()->Direct()->AddHandler(
+          [this, control](event::MouseButtonEventArgs& args) {
+            if (!control->IsMouseCaptured()) return;
+            const auto button = args.GetMouseButton();
+            auto& down_point = FromButton(button);
+            if (down_point.has_value()) {
+              event_.Raise(ClickEventArgs(control, down_point.value(),
+                                          args.GetPoint(), button));
+              down_point = std::nullopt;
+            }
+          })));
+}
+}  // namespace cru::ui