fix: remove monorepo

app/lib/stores/files.ts

@@ -0,0 +1,220 @@
+import type { PathWatcherEvent, WebContainer } from '@webcontainer/api';
+import { getEncoding } from 'istextorbinary';
+import { map, type MapStore } from 'nanostores';
+import { Buffer } from 'node:buffer';
+import * as nodePath from 'node:path';
+import { bufferWatchEvents } from '~/utils/buffer';
+import { WORK_DIR } from '~/utils/constants';
+import { computeFileModifications } from '~/utils/diff';
+import { createScopedLogger } from '~/utils/logger';
+import { unreachable } from '~/utils/unreachable';
+
+const logger = createScopedLogger('FilesStore');
+
+const utf8TextDecoder = new TextDecoder('utf8', { fatal: true });
+
+export interface File {
+  type: 'file';
+  content: string;
+  isBinary: boolean;
+}
+
+export interface Folder {
+  type: 'folder';
+}
+
+type Dirent = File | Folder;
+
+export type FileMap = Record<string, Dirent | undefined>;
+
+export class FilesStore {
+  #webcontainer: Promise<WebContainer>;
+
+  /**
+   * Tracks the number of files without folders.
+   */
+  #size = 0;
+
+  /**
+   * @note Keeps track all modified files with their original content since the last user message.
+   * Needs to be reset when the user sends another message and all changes have to be submitted
+   * for the model to be aware of the changes.
+   */
+  #modifiedFiles: Map<string, string> = import.meta.hot?.data.modifiedFiles ?? new Map();
+
+  /**
+   * Map of files that matches the state of WebContainer.
+   */
+  files: MapStore<FileMap> = import.meta.hot?.data.files ?? map({});
+
+  get filesCount() {
+    return this.#size;
+  }
+
+  constructor(webcontainerPromise: Promise<WebContainer>) {
+    this.#webcontainer = webcontainerPromise;
+
+    if (import.meta.hot) {
+      import.meta.hot.data.files = this.files;
+      import.meta.hot.data.modifiedFiles = this.#modifiedFiles;
+    }
+
+    this.#init();
+  }
+
+  getFile(filePath: string) {
+    const dirent = this.files.get()[filePath];
+
+    if (dirent?.type !== 'file') {
+      return undefined;
+    }
+
+    return dirent;
+  }
+
+  getFileModifications() {
+    return computeFileModifications(this.files.get(), this.#modifiedFiles);
+  }
+
+  resetFileModifications() {
+    this.#modifiedFiles.clear();
+  }
+
+  async saveFile(filePath: string, content: string) {
+    const webcontainer = await this.#webcontainer;
+
+    try {
+      const relativePath = nodePath.relative(webcontainer.workdir, filePath);
+
+      if (!relativePath) {
+        throw new Error(`EINVAL: invalid file path, write '${relativePath}'`);
+      }
+
+      const oldContent = this.getFile(filePath)?.content;
+
+      if (!oldContent) {
+        unreachable('Expected content to be defined');
+      }
+
+      await webcontainer.fs.writeFile(relativePath, content);
+
+      if (!this.#modifiedFiles.has(filePath)) {
+        this.#modifiedFiles.set(filePath, oldContent);
+      }
+
+      // we immediately update the file and don't rely on the `change` event coming from the watcher
+      this.files.setKey(filePath, { type: 'file', content, isBinary: false });
+
+      logger.info('File updated');
+    } catch (error) {
+      logger.error('Failed to update file content\n\n', error);
+
+      throw error;
+    }
+  }
+
+  async #init() {
+    const webcontainer = await this.#webcontainer;
+
+    webcontainer.watchPaths(
+      { include: [`${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': {
+          if (type === 'add_file') {
+            this.#size++;
+          }
+
+          let content = '';
+
+          /**
+           * @note This check is purely for the editor. The way we detect this is not
+           * bullet-proof and it's a best guess so there might be false-positives.
+           * The reason we do this is because we don't want to display binary files
+           * in the editor nor allow to edit them.
+           */
+          const isBinary = isBinaryFile(buffer);
+
+          if (!isBinary) {
+            content = this.#decodeFileContent(buffer);
+          }
+
+          this.files.setKey(sanitizedPath, { type: 'file', content, isBinary });
+
+          break;
+        }
+        case 'remove_file': {
+          this.#size--;
+          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 utf8TextDecoder.decode(buffer);
+    } catch (error) {
+      console.log(error);
+      return '';
+    }
+  }
+}
+
+function isBinaryFile(buffer: Uint8Array | undefined) {
+  if (buffer === undefined) {
+    return false;
+  }
+
+  return getEncoding(convertToBuffer(buffer), { chunkLength: 100 }) === 'binary';
+}
+
+/**
+ * Converts a `Uint8Array` into a Node.js `Buffer` by copying the prototype.
+ * The goal is to  avoid expensive copies. It does create a new typed array
+ * but that's generally cheap as long as it uses the same underlying
+ * array buffer.
+ */
+function convertToBuffer(view: Uint8Array): Buffer {
+  const buffer = new Uint8Array(view.buffer, view.byteOffset, view.byteLength);
+
+  Object.setPrototypeOf(buffer, Buffer.prototype);
+
+  return buffer as Buffer;
+}