Step 88: drag-and-drop open

editor/src/DragDropHandler.h

@@ -0,0 +1,24 @@
+#pragma once
+// Step 88: Drag-and-drop handler
+
+#include <string>
+#include <functional>
+#include <filesystem>
+
+class DragDropHandler {
+public:
+    using FileCallback = std::function<void(const std::string&)>;
+    using FolderCallback = std::function<void(const std::string&)>;
+
+    static void handleDrop(const std::string& path,
+                           const FileCallback& onFile,
+                           const FolderCallback& onFolder) {
+        if (path.empty()) return;
+        std::filesystem::path p(path);
+        if (std::filesystem::is_directory(p)) {
+            if (onFolder) onFolder(path);
+        } else {
+            if (onFile) onFile(path);
+        }
+    }
+};