feat(workbench): add file tree and hook up editor

packages/bolt/app/lib/stores/files.ts

@@ -0,0 +1,94 @@
+import type { PathWatcherEvent, WebContainer } from '@webcontainer/api';
+import { map } from 'nanostores';
+import { bufferWatchEvents } from '../../utils/buffer';
+import { WORK_DIR } from '../../utils/constants';
+
+const textDecoder = new TextDecoder('utf8', { fatal: true });
+
+interface File {
+  type: 'file';
+  content: string;
+}
+
+interface Folder {
+  type: 'folder';
+}
+
+type Dirent = File | Folder;
+
+export type FileMap = Record<string, Dirent | undefined>;
+
+export class FilesStore {
+  #webcontainer: Promise<WebContainer>;
+
+  files = map<FileMap>({});
+
+  constructor(webcontainerPromise: Promise<WebContainer>) {
+    this.#webcontainer = webcontainerPromise;
+
+    this.#init();
+  }
+
+  async #init() {
+    const webcontainer = await this.#webcontainer;
+
+    webcontainer.watchPaths(
+      { include: [`${WORK_DIR}/**`], exclude: ['**/node_modules', '.git'], includeContent: true },
+      bufferWatchEvents(100, this.#processEventBuffer.bind(this)),
+    );
+  }
+
+  #processEventBuffer(events: Array<[events: PathWatcherEvent[]]>) {
+    const watchEvents = events.flat(2);
+
+    for (const { type, path, buffer } of watchEvents) {
+      // remove any trailing slashes
+      const sanitizedPath = path.replace(/\/+$/g, '');
+
+      switch (type) {
+        case 'add_dir': {
+          // we intentionally add a trailing slash so we can distinguish files from folders in the file tree
+          this.files.setKey(sanitizedPath, { type: 'folder' });
+          break;
+        }
+        case 'remove_dir': {
+          this.files.setKey(sanitizedPath, undefined);
+
+          for (const [direntPath] of Object.entries(this.files)) {
+            if (direntPath.startsWith(sanitizedPath)) {
+              this.files.setKey(direntPath, undefined);
+            }
+          }
+
+          break;
+        }
+        case 'add_file':
+        case 'change': {
+          this.files.setKey(sanitizedPath, { type: 'file', content: this.#decodeFileContent(buffer) });
+          break;
+        }
+        case 'remove_file': {
+          this.files.setKey(sanitizedPath, undefined);
+          break;
+        }
+        case 'update_directory': {
+          // we don't care about these events
+          break;
+        }
+      }
+    }
+  }
+
+  #decodeFileContent(buffer?: Uint8Array) {
+    if (!buffer || buffer.byteLength === 0) {
+      return '';
+    }
+
+    try {
+      return textDecoder.decode(buffer);
+    } catch (error) {
+      console.log(error);
+      return '';
+    }
+  }
+}