1 files changed, 113 insertions, 0 deletions
diff --git a/src/ui/controls/text_common.cpp b/src/ui/controls/text_common.cpp
new file mode 100644
index 00000000..d6bcdd03
--- /dev/null
+++ b/src/ui/controls/text_common.cpp
@@ -0,0 +1,113 @@
+#include "cru/ui/controls/text_common.hpp"
+
+#include "cru/common/logger.hpp"
+#include "cru/platform/graph/font.hpp"
+#include "cru/platform/graph/painter.hpp"
+#include "cru/platform/native/ui_application.hpp"
+#include "cru/ui/control.hpp"
+#include "cru/ui/render/canvas_render_object.hpp"
+#include "cru/ui/render/text_render_object.hpp"
+
+#include <cassert>
+
+namespace cru::ui::controls {
+using platform::graph::ITextLayout;
+
+constexpr float caret_width = 2;
+constexpr long long caret_blink_duration = 500;
+
+TextControlService::TextControlService(Control* control,
+                                       ITextControl* text_control)
+    : control_(control), text_control_(text_control) {
+  event_revoker_guards_.push_back(
+      EventRevokerGuard{control->MouseDownEvent()->Direct()->AddHandler(
+          [this](event::MouseButtonEventArgs& args) {
+            if (this->select_down_button_.has_value()) {
+              return;
+            } else {
+              if (!this->control_->CaptureMouse()) return;
+              const auto text_render_object =
+                  this->text_control_->GetTextRenderObject();
+              this->select_down_button_ = args.GetButton();
+              const auto result = text_render_object->TextHitTest(
+                  text_render_object->FromRootToContent(args.GetPoint()));
+              const auto position = result.position + (result.trailing ? 1 : 0);
+              this->select_start_position_ = position;
+              log::Debug("Begin to select text. Position: {}", position);
+            }
+          })});
+
+  event_revoker_guards_.push_back(
+      EventRevokerGuard{control->MouseMoveEvent()->Direct()->AddHandler(
+          [this](event::MouseEventArgs& args) {
+            if (this->select_down_button_.has_value()) {
+              const auto text_render_object =
+                  this->text_control_->GetTextRenderObject();
+              const auto result = text_render_object->TextHitTest(
+                  text_render_object->FromRootToContent(args.GetPoint()));
+              const auto position = result.position + (result.trailing ? 1 : 0);
+              this->caret_position_ = position;
+              log::Debug("Text select range: {} : {}.", position,
+                         this->select_start_position_);
+              this->text_control_->GetTextRenderObject()->SetSelectionRange(
+                  TextRange::FromTwoSides(
+                      static_cast<unsigned>(position),
+                      static_cast<unsigned>(this->select_start_position_)));
+              this->text_control_->GetTextRenderObject()->InvalidatePaint();
+              this->text_control_->GetCaretRenderObject()->InvalidatePaint();
+            }
+          })});
+
+  event_revoker_guards_.push_back(
+      EventRevokerGuard{control->MouseUpEvent()->Direct()->AddHandler(
+          [this](event::MouseButtonEventArgs& args) {
+            if (this->select_down_button_.has_value() &&
+                this->select_down_button_.value() == args.GetButton()) {
+              this->control_->ReleaseMouse();
+              this->select_down_button_ = std::nullopt;
+              log::Debug("End selecting text.");
+            }
+          })});
+}
+
+TextControlService::~TextControlService() { TearDownCaretTimer(); }
+
+void TextControlService::SetCaretVisible(bool visible) {
+  if (visible) {
+    SetupCaretTimer();
+  } else {
+    TearDownCaretTimer();
+  }
+}
+
+void TextControlService::DrawCaret(platform::graph::IPainter* painter) {
+  if (caret_show_) {
+    const auto text_render_object = text_control_->GetTextRenderObject();
+    const auto point = text_render_object->TextSingleRect(
+        caret_position_, false);  // Maybe cache the result???
+    painter->FillRectangle(
+        Rect{point,
+             Size{caret_width, text_render_object->GetFont()->GetFontSize()}},
+        text_control_->GetCaretBrush());
+  }
+}
+
+void TextControlService::SetupCaretTimer() {
+  if (caret_visible_) return;
+
+  caret_visible_ = true;
+  caret_timer_tag_ =
+      platform::native::IUiApplication::GetInstance()->SetInterval(
+          std::chrono::milliseconds(caret_blink_duration), [this] {
+            this->caret_show_ = !this->caret_show_;
+            this->text_control_->GetCaretRenderObject()->InvalidatePaint();
+          });
+}
+
+void TextControlService::TearDownCaretTimer() {
+  if (!caret_visible_) return;
+  caret_visible_ = false;
+  platform::native::IUiApplication::GetInstance()->CancelTimer(
+      caret_timer_tag_);
+}
+}  // namespace cru::ui::controls