Fix file drop

frontend/webEditor/src/serialize/di.config.ts

@@ -9,6 +9,7 @@ import { SaveJsonFileCommand } from "./saveJsonFile";
 import { SaveDfdAndDdFileCommand } from "./saveDfdAndDdFile";
 import { AnalyzeCommand } from "./analyze";
 import { LoadFromUrlCommand } from "./LoadUrl";
+import { JsonDropHandler, LoadDroppedFileCommand } from "./dropListener";
 
 export const serializeModule = new ContainerModule((bind, unbind, isBound, rebind) => {
     const context = { bind, unbind, isBound, rebind };
@@ -20,6 +21,9 @@ export const serializeModule = new ContainerModule((bind, unbind, isBound, rebin
     configureCommand(context, SaveJsonFileCommand);
     configureCommand(context, SaveDfdAndDdFileCommand);
     configureCommand(context, AnalyzeCommand);
+    configureCommand(context, LoadDroppedFileCommand);
+
+    bind(TYPES.MouseListener).to(JsonDropHandler);
 
     rebind(TYPES.IModelFactory).to(DfdModelFactory);
 });

frontend/webEditor/src/serialize/dropListener.ts

@@ -0,0 +1,82 @@
+import { inject, injectable } from "inversify";
+import { ActionDispatcher, ILogger, MouseListener, SModelElementImpl, TYPES } from "sprotty";
+import { Action } from "sprotty-protocol";
+import { FileData, LoadJsonCommand } from "./loadJson";
+import { SavedDiagram } from "./SavedDiagram";
+import { SETTINGS } from "../settings/Settings";
+import { ConstraintRegistry } from "../constraint/constraintRegistry";
+import { FileName } from "../fileName/fileName";
+import { LabelTypeRegistry } from "../labels/LabelTypeRegistry";
+import { LoadingIndicator } from "../loadingIndicator/loadingIndicator";
+import { EditorModeController } from "../settings/editorMode";
+
+@injectable()
+export class JsonDropHandler extends MouseListener {
+    constructor(@inject(TYPES.ILogger) private readonly logger: ILogger) {
+        super();
+    }
+
+    drop(_target: SModelElementImpl, ev: DragEvent): Promise<Action>[] {
+        this.logger.log(this, "Drop event detected", ev);
+
+        const file = ev.dataTransfer?.files[0];
+        if (!file) {
+            return [];
+        }
+
+        if (file.type !== "application/json") {
+            return [];
+        }
+
+        // Prevent default behavior which would open the file in the browser
+        ev.preventDefault();
+
+        return [file.text().then((t) => LoadDroppedFileAction.create(file.name, JSON.parse(t)))];
+    }
+}
+
+interface LoadDroppedFileAction extends Action {
+    file: FileData<SavedDiagram>;
+}
+
+namespace LoadDroppedFileAction {
+    export const KIND = "loadDroppedFileAction";
+    export function create(fileName: string, content: SavedDiagram): LoadDroppedFileAction {
+        return {
+            kind: KIND,
+            file: {
+                fileName,
+                content,
+            },
+        };
+    }
+}
+
+export class LoadDroppedFileCommand extends LoadJsonCommand {
+    static readonly KIND = LoadDroppedFileAction.KIND;
+
+    constructor(
+        @inject(TYPES.Action) private readonly action: LoadDroppedFileAction,
+        @inject(TYPES.ILogger) logger: ILogger,
+        @inject(LabelTypeRegistry) labelTypeRegistry: LabelTypeRegistry,
+        @inject(ConstraintRegistry) constraintRegistry: ConstraintRegistry,
+        @inject(SETTINGS.Mode) editorModeController: EditorModeController,
+        @inject(TYPES.IActionDispatcher) actionDispatcher: ActionDispatcher,
+        @inject(FileName) fileName: FileName,
+        @inject(LoadingIndicator) loadingIndicator: LoadingIndicator,
+    ) {
+        super(
+            logger,
+            labelTypeRegistry,
+            constraintRegistry,
+            editorModeController,
+            actionDispatcher,
+            fileName,
+            loadingIndicator,
+        );
+    }
+
+    protected async getFile(): Promise<FileData<SavedDiagram> | undefined> {
+        return this.action.file;
+    }
+}