Automatic opening

resources/diagram-panel.html

@@ -12,23 +12,21 @@
     <div id="diagram-container"></div>
     <script type="module">
       const vscode = acquireVsCodeApi();
+      /** Waits for the page to be fully loaded before trying to render the graph */
       window.addEventListener('load', async() => {
         await vscode.postMessage({
           command: 'panel-content-loaded'
-        })
+        });
       });
       import mermaid from 'https://cdn.jsdelivr.net/npm/mermaid/+esm';
       (async () => {
         try {
+          /** The diagram container */
           const diagramContainerEl = document.getElementById('diagram-container');
 
-          function updateState(partialState) {
-            vscode.setState({
-              ...vscode.getState(),
-              ...partialState
-            });
-          }
-
+          /**
+           * Renders the provided graph definition
+           */
           async function updateDiagram({ graphDefinition }) {
             try {
               const { svg, bindFunctions } = await mermaid.render('sw-diagram', graphDefinition);
@@ -38,7 +36,6 @@
                 command: 'diagram-rendered',
                 svg: sanitizedSvg
               });
-              updateState({ graphDefinition });
             }
             catch (ex) {
               await vscode.postMessage({
@@ -49,6 +46,9 @@
             }
           }
 
+          /**
+           * Generates a PNG using a canvas
+           */
           function generatePng() {
             const canvas = document.createElement('canvas');
             const context = canvas.getContext('2d');
@@ -76,6 +76,7 @@
             img.src = `data:image/svg+xml;charset=utf-8;base64,${base64}`;
           }
 
+          /** Handles commands from the DiagramPanel */
           window.addEventListener('message', async (event) => {
             const { command, ...args } = event.data;
             switch (command) {
@@ -88,14 +89,10 @@
             }
           });
 
+          /** Init Mermaid JS */
           mermaid.initialize({
             startOnLoad: false
           });
-
-          const state = vscode.getState();
-          if (state?.graphDefinition) {
-            await updateDiagram({ graphDefinition: state.graphDefinition });
-          }
         }
         catch (ex) {
           await vscode.postMessage({

src/diagram-panel.ts

@@ -5,21 +5,46 @@ import { MermaidDiagram, Specification } from '@severlessworkflow/sdk-typescript
 
 export const diagramViewPanelType = 'serverlessWorkflowDiagramPanel';
 export const diagramViewPanelTitle = 'Diagram Preview';
+/**
+ * Type representing the mode of the diagram panel.
+ * - preview: opens a panel and displays the diagram
+ * - svg: generates a SVG from the diagram
+ * - png: generates a PNG from the diagram
+ */
 export type DiagramPanelMode = 'preview' | 'svg' | 'png';
+/**
+ * Options for the diagram panel.
+ */
 export type DiagramPanelOptions = {
   mode?: DiagramPanelMode
 };
 
 let panelContent: string | undefined;
 
+/**
+ * Class representing a diagram panel.
+ */
 export class DiagramPanel {
   #context: vscode.ExtensionContext;
   #panel: vscode.WebviewPanel | undefined;
   #subscriptions: vscode.Disposable[] = [];
   #target: vscode.TextDocument | undefined;
   #disposeEventEmitter: vscode.EventEmitter<void> = new vscode.EventEmitter<void>();
   #mode: DiagramPanelMode;
+  /** Gets the current @see vscode.TextDocument target */
+  get target(): vscode.TextDocument | undefined {
+    return this.#target;
+  }
+  /** Gets the current @see DiagramPanelMode */
+  get mode(): DiagramPanelMode {
+    return this.#mode;
+  }
 
+  /**
+   * Instanciates a new @see DiagramPanel
+   * @param context The @see vscode.ExtensionContext
+   * @param options The @see DiagramPanelOptions to instanciate the panel with
+   */
   constructor(context: vscode.ExtensionContext, options?: DiagramPanelOptions) {
     this.#context = context;
     this.#mode = options?.mode || 'preview';
@@ -59,10 +84,17 @@ export class DiagramPanel {
     );
   }
 
+  /**
+   * Event that fires when the panel is disposed.
+   */
   public get onDidDispose(): vscode.Event<void> {
     return this.#disposeEventEmitter.event;
   }
-
+
+  /**
+   * Renders the panel with the specified target text document.
+   * @param target The target text document.
+   */
   async render(target: vscode.TextDocument): Promise<void> {
     if (!this.#panel) {
       console.warn('No active diagram panel.');
@@ -80,10 +112,28 @@ export class DiagramPanel {
     this.#panel.webview.html = panelContent;
   }
 
+  /**
+   * Shows the diagram
+   * @returns 
+   */
+  async focus(): Promise<void> {
+    if (!this.#panel) {
+      console.warn('No active diagram panel.');
+      return;
+    }
+    this.#panel.reveal(undefined, true);
+  }
+
+  /**
+   * Disposes the panel.
+   */
   dispose() {
     this.#panel?.dispose();
   }
 
+  /**
+   * Initializes the panel.
+   */
   async #initPanel(): Promise<void> {
     if (panelContent) {
       return;
@@ -94,6 +144,10 @@ export class DiagramPanel {
     panelContent = decoder.decode(panelSourceContent);
   }
 
+  /**
+   * Gets the destination file URI when generating an image.
+   * @returns The destination file URI.
+   */
   #getFileDestination(): vscode.Uri | undefined {
     if (!this.#target) {
       return;
@@ -114,6 +168,10 @@ export class DiagramPanel {
     return destination;
   }
 
+  /**
+   * Saves the diagram to a file.
+   * @param buffer The buffer to save.
+   */
   async #saveToFile(buffer: Buffer): Promise<void> {
     try {
       let destination = this.#getFileDestination();
@@ -133,6 +191,10 @@ export class DiagramPanel {
     this.dispose();
   }
 
+  /**
+   * Handles receiving message from the panel.
+   * @param message The message received.
+   */
   async #onPanelReceiveMessage(message: any): Promise<void> {    
     const { command, ...args } = message;
     switch (command) {
@@ -167,7 +229,10 @@ export class DiagramPanel {
       }
     }
   }
-
+
+  /**
+   * Updates the diagram.
+   */
   async #updateDiagram(): Promise<void> {
     if (!this.#panel) {
       console.warn('No active diagram panel.');

src/extension.ts

@@ -5,7 +5,35 @@ import * as path from 'path';
 import { DiagramPanel, DiagramPanelMode } from './diagram-panel';
 
 const supportedExtensions = [ '.json', '.yml', '.yaml' ];
+let diagramPanels: Array<DiagramPanel> = [];
 
+/**
+ * Creates and registers a diagram panel
+ * @param context The current @see vscode.ExtensionContext
+ * @param mode The @see DiagramPanelMode
+ * @param target The target @see vscode.TextDocument
+ */
+async function registerDiagramPanel(context: vscode.ExtensionContext, mode: DiagramPanelMode, target: vscode.TextDocument): Promise<void> {
+	let diagramPanel: DiagramPanel | undefined = diagramPanels.find(panel => panel.mode === mode && panel.target === target);
+	if (diagramPanel) {
+		await diagramPanel.focus();
+		return;
+	}
+	diagramPanel = new DiagramPanel(context, { mode });
+	diagramPanels.push(diagramPanel);
+	diagramPanel.onDidDispose((_) => {
+		diagramPanels = diagramPanels.filter(panel => panel !== diagramPanel);
+	}, null, context.subscriptions);
+	await diagramPanel.render(target!);
+}
+
+/**
+ * Handles a command used to open/export a diagram
+ * @param context The current @see vscode.ExtensionContext
+ * @param mode The @see DiagramPanelMode
+ * @param selectionSource The explorer menu item the action has been made on
+ * @param selectedItems The selected items in the explorer menu
+ */
 async function handleDiagramCommand(context: vscode.ExtensionContext, mode: DiagramPanelMode, selectionSource?: vscode.Uri, selectedItems?: vscode.Uri[]): Promise<void> {
 	let title: string = 'Loading';
 	switch (mode) {
@@ -19,35 +47,51 @@ async function handleDiagramCommand(context: vscode.ExtensionContext, mode: Diag
 			title = 'Generating PNG...';
 			break;
 	}
-	vscode.window.withProgress({
-    location: vscode.ProgressLocation.Window,
-    cancellable: false,
-    title
-	}, async() => {
-	if (selectionSource && selectedItems) {
-		for (let item of selectedItems) {
-			const ext = path.extname(item.fsPath);
-			if (supportedExtensions.includes(ext)) {
-				const target = await vscode.workspace.openTextDocument(item);
-				const diagramPanel = new DiagramPanel(context, { mode });
-				await diagramPanel.render(target!);
+	vscode.window.withProgress(
+		{
+			location: vscode.ProgressLocation.Window,
+			cancellable: false,
+			title
+		}, 
+		async() => {
+			if (selectionSource && selectedItems) {
+				for (let item of selectedItems) {
+					const ext = path.extname(item.fsPath);
+					if (supportedExtensions.includes(ext)) {
+						const target = await vscode.workspace.openTextDocument(item);
+						if (target) {
+							registerDiagramPanel(context, mode, target);
+						}
+					}
+				}
+				return;
+			}
+			const target = vscode.window.activeTextEditor?.document;
+			if (target) {
+				registerDiagramPanel(context, mode, target);
 			}
 		}
-		return;
-	}
-	else {
-		const target = vscode.window.activeTextEditor?.document;
-		if (target) {
-			const diagramPanel = new DiagramPanel(context, { mode });
-			await diagramPanel.render(target);
-		}
-		return;
-	}
-});
+	);
 }
 
+/**
+ * Activate the extension.
+ * @param context The context of the extension.
+ */
 export function activate(context: vscode.ExtensionContext) {
-
+	// Detects when a file is focused
+	vscode.window.onDidChangeActiveTextEditor(editor => {
+		if ((editor?.document?.languageId === 'json' || editor?.document?.languageId === 'yaml')
+			&& editor?.document?.fileName.includes('.sw.')
+		) {
+			registerDiagramPanel(context, 'preview', editor?.document /* === vscode.window.activeTextEditor?.document*/);
+		}
+	}, null, context.subscriptions);
+	//Detect when a file is closed
+	vscode.workspace.onDidCloseTextDocument(document => {
+		diagramPanels.filter(panel => panel.target === document).forEach(panel => panel.dispose());
+	}, null, context.subscriptions);
+	// Handles commands (palette/right click/keybinding, see package.json for more info)
   context.subscriptions.push(
     vscode.commands.registerCommand('serverlessWorkflow.diagram.preview', handleDiagramCommand.bind(null, context, 'preview'))
   );
@@ -57,5 +101,4 @@ export function activate(context: vscode.ExtensionContext) {
   context.subscriptions.push(
     vscode.commands.registerCommand('serverlessWorkflow.diagram.png', handleDiagramCommand.bind(null, context, 'png'))
   );
-
 }