Add offline PlantUML renderer option

App.tsx

@@ -1090,7 +1090,7 @@ const MainApp: React.FC = () => {
     }
 
     const renderMainContent = () => {
-        if (view === 'info') return <InfoView />;
+        if (view === 'info') return <InfoView settings={settings} />;
         if (view === 'settings') return <SettingsView settings={settings} onSave={saveSettings} discoveredServices={discoveredServices} onDetectServices={handleDetectServices} isDetecting={isDetecting} commands={enrichedCommands} />;
 
         if (activeTemplate) {

FUNCTIONAL_MANUAL.md

@@ -133,14 +133,25 @@ Accessed via the gear icon in the title bar. The settings are organized into cat
 - **LLM Provider:** Configure your connection to a local AI service. You can detect running services and select a model.
 - **Appearance:** Change the UI scale and choose from different icon sets.
 - **Keyboard Shortcuts:** View and customize keyboard shortcuts for all major application actions. You can record a new key combination for any command.
-- **General:** Configure application behavior, like auto-saving logs and opting into pre-release updates.
+- **General:** Configure application behavior, like auto-saving logs, opting into pre-release updates, and choosing how PlantUML diagrams are rendered.
 - **Database:** View detailed statistics about your local database file, and perform maintenance tasks such as creating a compressed backup, checking file integrity, and optimizing the database size (`VACUUM`).
 - **Advanced:** View and edit the raw JSON configuration file using an interactive tree or a raw text editor, and import/export your settings.
 
 ### Info View
 
 Accessed via the info icon in the title bar. This view contains tabs for reading the application's `README.md`, this `FUNCTIONAL_MANUAL.md`, the `TECHNICAL_MANUAL.md`, and the `VERSION_LOG.md`.
 
+#### PlantUML Rendering Modes
+
+The **General** settings category includes a **PlantUML Rendering** selector. Choose between:
+
+- **Remote (plantuml.com):** Encodes the diagram and requests the SVG from the public PlantUML server.
+- **Offline (local renderer):** Invokes the bundled PlantUML engine inside the desktop application. This mode requires a local Java Runtime Environment and access to Graphviz (or the bundled `viz.js` assets) so the renderer can generate diagrams without contacting plantuml.com.
+
+If the Java runtime is unavailable, DocForge will report the error in the preview and you can switch back to remote rendering at any time.
+
+The chosen rendering mode is used for PlantUML code blocks inside Markdown documents *and* for standalone `.puml` documents rendered through the dedicated PlantUML previewer.
+
 ### Logger Panel
 
 Accessed via the terminal icon in the title bar, this panel is your primary tool for debugging and monitoring application activity.

TECHNICAL_MANUAL.md

@@ -14,6 +14,7 @@ This document provides a technical overview of the DocForge application's archit
 -   **Bundler:** [esbuild](https://esbuild.github.io/) for fast and efficient bundling of the application's source code.
 -   **Styling:** [Tailwind CSS](https://tailwindcss.com/) for a utility-first CSS framework.
 -   **Packaging:** [electron-builder](https://www.electron.build/) for creating distributable application packages.
+-   **Diagram Rendering:** [PlantUML](https://plantuml.com/) via either the public plantuml.com service or the bundled [`node-plantuml`](https://www.npmjs.com/package/node-plantuml) renderer. Offline rendering requires a locally installed Java Runtime Environment and access to Graphviz (or the cached `viz.js` binary) so that diagrams can be rendered without network access.
 
 ---
 
@@ -93,7 +94,8 @@ This system provides a consistent and extensible editing experience for all docu
 -   **`CodeEditor.tsx`:** A React component that wraps and configures the Monaco Editor instance. It's responsible for managing the editor's content, theme, and language for syntax highlighting based on props.
 -   **`PreviewPane.tsx`:** This component is responsible for displaying the rendered output of a document. It debounces content updates for performance and uses the `PreviewService` to get the correct output.
 -   **`services/previewService.ts`:** This service acts as a registry for all available renderer "plugins." It exposes a method, `getRendererForLanguage()`, which finds and returns the appropriate renderer for a given language ID (e.g., 'markdown').
--   **Renderer Plugins (`services/preview/`):** Each file format with a preview is supported by a dedicated renderer class that implements the `IRenderer` interface. This makes the system highly extensible: to support a new format, one only needs to create a new renderer class and add it to the `previewService` registry. Currently, renderers for Markdown, HTML, and plaintext (fallback) are implemented.
+-   **Renderer Plugins (`services/preview/`):** Each file format with a preview is supported by a dedicated renderer class that implements the `IRenderer` interface. This makes the system highly extensible: to support a new format, one only needs to create a new renderer class and add it to the `previewService` registry. The bundled plugins cover Markdown (with Mermaid + PlantUML support), standalone PlantUML documents, HTML, PDFs, common image formats, and a plaintext fallback renderer.
+    -   Both the Markdown renderer and the standalone PlantUML renderer share the `PlantUMLDiagram` component, which routes diagrams through either the remote plantuml.com server or the offline `node-plantuml` IPC bridge depending on the active setting.
 
 ### LLM Service (`services/llmService.ts`)
 

components/InfoView.tsx

@@ -2,6 +2,7 @@ import React, { useState, useEffect } from 'react';
 import PreviewPane from './PreviewPane';
 import Spinner from './Spinner';
 import { useLogger } from '../hooks/useLogger';
+import type { Settings } from '../types';
 
 type DocTab = 'Readme' | 'Functional Manual' | 'Technical Manual' | 'Version Log';
 
@@ -12,7 +13,11 @@ const docFiles: Record<DocTab, string> = {
   'Version Log': 'VERSION_LOG.md',
 };
 
-const InfoView: React.FC = () => {
+interface InfoViewProps {
+  settings: Settings;
+}
+
+const InfoView: React.FC<InfoViewProps> = ({ settings }) => {
   const [activeTab, setActiveTab] = useState<DocTab>('Readme');
   const [documents, setDocuments] = useState<Record<DocTab, string>>({
     'Readme': 'Loading...',
@@ -100,7 +105,7 @@ const InfoView: React.FC = () => {
             <span>Loading documentation...</span>
           </div>
         ) : (
-          <PreviewPane content={documents[activeTab]} language="markdown" addLog={addLog} />
+          <PreviewPane content={documents[activeTab]} language="markdown" addLog={addLog} settings={settings} />
         )}
       </div>
     </div>

components/PreviewPane.tsx

@@ -2,16 +2,17 @@ import React, { useState, useEffect } from 'react';
 import { previewService } from '../services/previewService';
 import Spinner from './Spinner';
 import { useTheme } from '../hooks/useTheme';
-import type { LogLevel } from '../types';
+import type { LogLevel, Settings } from '../types';
 
 interface PreviewPaneProps {
   content: string;
   language: string | null;
   onScroll?: (event: React.UIEvent<HTMLDivElement>) => void;
   addLog: (level: LogLevel, message: string) => void;
+  settings: Settings;
 }
 
-const PreviewPane = React.forwardRef<HTMLDivElement, PreviewPaneProps>(({ content, language, onScroll, addLog }, ref) => {
+const PreviewPane = React.forwardRef<HTMLDivElement, PreviewPaneProps>(({ content, language, onScroll, addLog, settings }, ref) => {
   const [renderedOutput, setRenderedOutput] = useState<React.ReactElement | null>(null);
   const [error, setError] = useState<string | null>(null);
   const [isLoading, setIsLoading] = useState(true);
@@ -28,7 +29,7 @@ const PreviewPane = React.forwardRef<HTMLDivElement, PreviewPaneProps>(({ conten
 
       setError(null);
       const renderer = previewService.getRendererForLanguage(language);
-      const result = await renderer.render(content, addLog, language);
+      const result = await renderer.render(content, addLog, language, settings);
 
       clearTimeout(loadingTimer);
       if (!isCancelled) {
@@ -57,7 +58,7 @@ const PreviewPane = React.forwardRef<HTMLDivElement, PreviewPaneProps>(({ conten
       isCancelled = true;
       clearTimeout(debounceTimer);
     };
-  }, [content, language, addLog, ref, onScroll]);
+  }, [content, language, addLog, ref, onScroll, settings]);
 
   return (
     <div className="w-full h-full bg-secondary">

components/PromptEditor.tsx

@@ -29,6 +29,9 @@ interface DocumentEditorProps {
 const PREVIEWABLE_LANGUAGES = new Set<string>([
   'markdown',
   'html',
+  'plantuml',
+  'puml',
+  'uml',
   'pdf',
   'application/pdf',
   'image',
@@ -62,6 +65,9 @@ const resolveDefaultViewMode = (mode: ViewMode | null | undefined, languageHint:
   if (normalizedHint === 'image' || normalizedHint.startsWith('image/')) {
     return 'preview';
   }
+  if (normalizedHint === 'plantuml' || normalizedHint === 'puml' || normalizedHint === 'uml') {
+    return 'preview';
+  }
   return 'edit';
 };
 
@@ -482,7 +488,7 @@ const DocumentEditor: React.FC<DocumentEditorProps> = ({ documentNode, onSave, o
             fontSize={settings.editorFontSize}
           />
         );
-    const preview = <PreviewPane ref={previewScrollRef} content={content} language={language} onScroll={handlePreviewScroll} addLog={addLog} />;
+    const preview = <PreviewPane ref={previewScrollRef} content={content} language={language} onScroll={handlePreviewScroll} addLog={addLog} settings={settings} />;
 
     switch(viewMode) {
         case 'edit': return editor;

components/SettingsView.tsx

@@ -1369,8 +1369,10 @@ requests"
 };
 
 const GeneralSettingsSection: React.FC<Pick<SectionProps, 'settings' | 'setCurrentSettings' | 'sectionRef'>> = ({ settings, setCurrentSettings, sectionRef }) => {
+    const isOfflineRendererAvailable = typeof window !== 'undefined' && !!window.electronAPI?.renderPlantUML;
+    const offlineRendererMessage = 'Offline rendering requires the desktop application with a local Java runtime.';
     return (
-         <div id="general" ref={sectionRef} className="py-6">
+            <div id="general" ref={sectionRef} className="py-6">
             <h2 className="text-lg font-semibold text-text-main mb-4">General</h2>
             <div className="space-y-6">
                  <SettingRow htmlFor="allowPrerelease" label="Receive Pre-releases" description="Get notified about new beta versions and test features early.">
@@ -1379,6 +1381,31 @@ const GeneralSettingsSection: React.FC<Pick<SectionProps, 'settings' | 'setCurre
                  <SettingRow htmlFor="autoSaveLogs" label="Auto-save Logs" description="Automatically save all logs to a daily file on your computer for debugging.">
                     <ToggleSwitch id="autoSaveLogs" checked={settings.autoSaveLogs} onChange={(val) => setCurrentSettings(s => ({...s, autoSaveLogs: val}))} />
                 </SettingRow>
+                 <SettingRow
+                    htmlFor="plantumlRendererMode"
+                    label="PlantUML Rendering"
+                    description="Choose whether PlantUML diagrams are rendered via the public server or the local renderer."
+                >
+                    <div className="flex flex-col items-end w-full md:items-end">
+                        <select
+                            id="plantumlRendererMode"
+                            value={settings.plantumlRendererMode}
+                            onChange={(event) => setCurrentSettings(prev => ({
+                                ...prev,
+                                plantumlRendererMode: event.target.value as Settings['plantumlRendererMode'],
+                            }))}
+                            className="w-full md:w-64 px-3 py-2 text-sm rounded-md border border-border-color bg-background text-text-main focus:outline-none focus:ring-2 focus:ring-primary/50"
+                        >
+                            <option value="remote">Remote (plantuml.com)</option>
+                            <option value="offline">Offline (local renderer)</option>
+                        </select>
+                        {!isOfflineRendererAvailable && (
+                            <p className={`mt-2 text-xs ${settings.plantumlRendererMode === 'offline' ? 'text-destructive-text' : 'text-text-secondary'} text-right md:text-left md:w-full`}>
+                                {offlineRendererMessage}
+                            </p>
+                        )}
+                    </div>
+                </SettingRow>
             </div>
         </div>
     );

constants.ts

@@ -24,6 +24,7 @@ export const DEFAULT_SETTINGS: Settings = {
   iconSet: 'heroicons',
   autoSaveLogs: false,
   allowPrerelease: false,
+  plantumlRendererMode: 'remote',
   uiScale: 100,
   documentTreeIndent: 16,
   documentTreeVerticalSpacing: 4,

docs/FUNCTIONAL_MANUAL.md

@@ -133,14 +133,25 @@ Accessed via the gear icon in the title bar. The settings are organized into cat
 - **LLM Provider:** Configure your connection to a local AI service. You can detect running services and select a model.
 - **Appearance:** Change the UI scale and choose from different icon sets.
 - **Keyboard Shortcuts:** View and customize keyboard shortcuts for all major application actions. You can record a new key combination for any command.
-- **General:** Configure application behavior, like auto-saving logs and opting into pre-release updates.
+- **General:** Configure application behavior, like auto-saving logs, opting into pre-release updates, and choosing how PlantUML diagrams are rendered.
 - **Database:** View detailed statistics about your local database file, and perform maintenance tasks such as creating a compressed backup, checking file integrity, and optimizing the database size (`VACUUM`).
 - **Advanced:** View and edit the raw JSON configuration file using an interactive tree or a raw text editor, and import/export your settings.
 
 ### Info View
 
 Accessed via the info icon in the title bar. This view contains tabs for reading the application's `README.md`, this `FUNCTIONAL_MANUAL.md`, the `TECHNICAL_MANUAL.md`, and the `VERSION_LOG.md`.
 
+#### PlantUML Rendering Modes
+
+The **General** settings category includes a **PlantUML Rendering** selector. Choose between:
+
+- **Remote (plantuml.com):** Encodes the diagram and requests the SVG from the public PlantUML server.
+- **Offline (local renderer):** Invokes the bundled PlantUML engine inside the desktop application. This mode requires a local Java Runtime Environment and access to Graphviz (or the bundled `viz.js` assets) so the renderer can generate diagrams without contacting plantuml.com.
+
+If the Java runtime is unavailable, DocForge will report the error in the preview and you can switch back to remote rendering at any time.
+
+The chosen rendering mode is used for PlantUML code blocks inside Markdown documents *and* for standalone `.puml` documents rendered through the dedicated PlantUML previewer.
+
 ### Logger Panel
 
 Accessed via the terminal icon in the title bar, this panel is your primary tool for debugging and monitoring application activity.

docs/TECHNICAL_MANUAL.md

@@ -14,6 +14,7 @@ This document provides a technical overview of the DocForge application's archit
 -   **Bundler:** [esbuild](https://esbuild.github.io/) for fast and efficient bundling of the application's source code.
 -   **Styling:** [Tailwind CSS](https://tailwindcss.com/) for a utility-first CSS framework.
 -   **Packaging:** [electron-builder](https://www.electron.build/) for creating distributable application packages.
+-   **Diagram Rendering:** [PlantUML](https://plantuml.com/) via either the public plantuml.com service or the bundled [`node-plantuml`](https://www.npmjs.com/package/node-plantuml) renderer. Offline rendering requires a locally installed Java Runtime Environment and access to Graphviz (or the cached `viz.js` binary) so that diagrams can be rendered without network access.
 
 ---
 
@@ -93,7 +94,8 @@ This system provides a consistent and extensible editing experience for all docu
 -   **`CodeEditor.tsx`:** A React component that wraps and configures the Monaco Editor instance. It's responsible for managing the editor's content, theme, and language for syntax highlighting based on props.
 -   **`PreviewPane.tsx`:** This component is responsible for displaying the rendered output of a document. It debounces content updates for performance and uses the `PreviewService` to get the correct output.
 -   **`services/previewService.ts`:** This service acts as a registry for all available renderer "plugins." It exposes a method, `getRendererForLanguage()`, which finds and returns the appropriate renderer for a given language ID (e.g., 'markdown').
--   **Renderer Plugins (`services/preview/`):** Each file format with a preview is supported by a dedicated renderer class that implements the `IRenderer` interface. This makes the system highly extensible: to support a new format, one only needs to create a new renderer class and add it to the `previewService` registry. Currently, renderers for Markdown, HTML, and plaintext (fallback) are implemented.
+-   **Renderer Plugins (`services/preview/`):** Each file format with a preview is supported by a dedicated renderer class that implements the `IRenderer` interface. This makes the system highly extensible: to support a new format, one only needs to create a new renderer class and add it to the `previewService` registry. The bundled plugins cover Markdown (with Mermaid + PlantUML support), standalone PlantUML documents, HTML, PDFs, common image formats, and a plaintext fallback renderer.
+    -   Both the Markdown renderer and the standalone PlantUML renderer share the `PlantUMLDiagram` component, which routes diagrams through either the remote plantuml.com server or the offline `node-plantuml` IPC bridge depending on the active setting.
 
 ### LLM Service (`services/llmService.ts`)