Bolt.new

WorkbenchStore is the central state management class for the Bolt.new workbench. It orchestrates the state for files, the code editor, terminal, previews, and AI-generated artifacts. It uses nanostores for reactive state management.

Key responsibilities include:

• File Management: Saving, resetting, and tracking unsaved files.
• Editor State: Managing the current document, selected file, and scroll positions.
• Terminal Control: Toggling visibility and attaching terminal instances.
• Artifact Management: Handling AI-generated artifacts and their associated ActionRunner instances.
• View Control: Managing whether the workbench is visible and switching between code and preview views.

import { workbenchStore } from '~/lib/stores/workbench';

// Example: Saving the current document
await workbenchStore.saveCurrentDocument();

// Example: Switching to preview view
workbenchStore.currentView.set('preview');

// Example: Checking for unsaved files
const unsaved = workbenchStore.unsavedFiles.get();
console.log(`You have ${unsaved.size} unsaved files.`);

The StreamingMessageParser is designed for incremental processing. It maintains a MessageState for every unique messageId provided to the .parse() method.

Internal State Management

• Position Tracking: The parser tracks the last processed character index (position) to ensure it doesn't re-process text or miss partial tags across chunks.
• Nesting Logic: It tracks whether the parser is currently insideArtifact or insideAction to correctly handle nested tags.
• Output Generation: The .parse() method returns a string containing the text that is not part of a tag. If an artifactElement factory is provided, the <boltArtifact> tags are replaced in the output with the string returned by that factory.

Workflow

1. Chunk 1: ... <boltArtifact id="a" title="t"> ...
   • onArtifactOpen is triggered.
   • Output contains the artifactElement placeholder.
2. Chunk 2: ... <boltAction type="shell"> ...
   • onActionOpen is triggered.
3. Chunk 3: ... </boltAction> </boltArtifact>
   • onActionClose and onArtifactClose are triggered.
4. Chunk 4: ...
   • Parser returns the remaining text normally.

The FilesStore class manages the state of files and folders within a WebContainer environment. It synchronizes the in-memory file map with the actual filesystem using a path watcher.

Key features include:

• Reactive State: Uses nanostores to provide a files MapStore that can be subscribed to for UI updates.
• File Tracking: Tracks file modifications to compute diffs, which is useful for informing AI models of changes.
• Binary Detection: Automatically detects if a file is binary to prevent attempting to render or edit non-text content in the editor.

Data Structures:

• File: { type: 'file', content: string, isBinary: boolean }
• Folder: { type: 'folder' }
• FileMap: A record mapping file paths (strings) to File | Folder | undefined.

import { FilesStore } from '~/lib/stores/files';

// Initialize with a WebContainer promise
const filesStore = new FilesStore(webcontainerPromise);

// Access the reactive file map
filesStore.files.listen((fileMap) => {
  console.log('Files updated:', fileMap);
});

When instantiating StreamingMessageParser, you can provide a StreamingMessageParserOptions object to control callback behavior and UI rendering.

Options

• callbacks?: ParserCallbacks: An object containing lifecycle hooks:
  • onArtifactOpen?: (data: ArtifactCallbackData) => void
  • onArtifactClose?: (data: ArtifactCallbackData) => void
  • onActionOpen?: (data: ActionCallbackData) => void
  • onActionClose?: (data: ActionCallbackData) => void
• artifactElement?: ElementFactory: A function used to generate a string representation of the artifact placeholder in the returned text. It receives { messageId: string } as an argument.

Callback Data Shapes

ArtifactCallbackData

{
  id: string;
  title: string;
  messageId: string;
}

ActionCallbackData

{
  artifactId: string;
  messageId: string;
  actionId: string;
  action: BoltAction; // Can be FileAction or ShellAction
}

The project uses UnoCSS for styling. The configuration includes custom presets for icons, theme-aware dark mode, and a comprehensive set of design tokens (colors, shortcuts, and rules).

Key configuration features:

• Presets: Uses presetUno with dark mode support via [data-theme="light/dark"] and presetIcons for icon management.
• Custom Icons: Icons are loaded from the ./icons/*.svg directory and registered under the bolt collection.
• Transformers: Includes transformerDirectives() to support @apply and other CSS directives.
• Theme Tokens: Extensive use of CSS variables (e.g., var(--bolt-elements-...)) for theme-aware components like buttons, sidebars, and terminals.

import { defineConfig, presetIcons, presetUno, transformerDirectives } from 'unocss';

export default defineConfig({
  presets: [
    presetUno({
      dark: {
        light: '[data-theme="light"]',
        dark: '[data-theme="dark"]',
      },
    }),
    presetIcons({
      warn: true,
      collections: {
        // custom collections
      },
    }),
  ],
  transformers: [transformerDirectives()],
});