refactor(new_editor): tighten app dependency boundaries

new_editor/include/XCEditor/Collections/UIEditorGridDragDrop.h

@@ -0,0 +1,73 @@
+#pragma once
+
+#include <XCEditor/Collections/UIEditorDragDropInteraction.h>
+
+#include <string_view>
+
+namespace XCEngine::UI::Editor::Collections::GridDragDrop {
+
+using ::XCEngine::UI::UIPoint;
+using DragDropInteraction::kDefaultDragThreshold;
+using DragDropInteraction::ProcessResult;
+using DragDropInteraction::State;
+
+inline void ResetTransientRequests(State& state) {
+    DragDropInteraction::ResetTransientRequests(state);
+}
+
+inline bool HasActivePointerCapture(const State& state) {
+    return DragDropInteraction::HasActivePointerCapture(state);
+}
+
+template <typename Callbacks>
+ProcessResult ProcessInputEvents(
+    State& state,
+    const std::vector<DragDropInteraction::UIInputEvent>& inputEvents,
+    Callbacks& callbacks,
+    float dragThreshold = kDefaultDragThreshold) {
+    struct AdaptedCallbacks {
+        Callbacks& callbacks;
+
+        std::string ResolveDraggableItem(const UIPoint& point) const {
+            return callbacks.ResolveDraggableItem(point);
+        }
+
+        void ResetDropTarget(State& state) const {
+            state.dropTargetItemId.clear();
+            state.validDropTarget = false;
+        }
+
+        void UpdateDropTarget(
+            State& state,
+            std::string_view draggedItemId,
+            const UIPoint& point) const {
+            state.dropTargetItemId =
+                callbacks.ResolveDropTargetItem(draggedItemId, point);
+            state.validDropTarget =
+                !state.dropTargetItemId.empty() &&
+                callbacks.CanDropOnItem(draggedItemId, state.dropTargetItemId);
+        }
+
+        bool IsItemSelected(std::string_view itemId) const {
+            return callbacks.IsItemSelected(itemId);
+        }
+
+        bool SelectDraggedItem(std::string_view itemId) const {
+            return callbacks.SelectDraggedItem(itemId);
+        }
+
+        bool CommitDrop(State& state, ProcessResult&) const {
+            return callbacks.CommitDropOnItem(
+                state.draggedItemId,
+                state.dropTargetItemId);
+        }
+    } adaptedCallbacks{ callbacks };
+
+    return DragDropInteraction::ProcessInputEvents(
+        state,
+        inputEvents,
+        adaptedCallbacks,
+        dragThreshold);
+}
+
+} // namespace XCEngine::UI::Editor::Collections::GridDragDrop