Fix

apps/web/messages/cs.json

@@ -198,6 +198,7 @@
   "editor_error_title": "Chyba při načítání souboru",
   "project_download_no_files": "V projektu nebyly nalezeny žádné soubory ke stažení",
   "project_layout_load_error": "Nepodařilo se načíst nastavení rozložení, používá se výchozí",
+  "project_save_before_leave_error": "Projektové soubory se nepodařilo uložit. Navigace byla zastavena, aby se změny neztratily.",
   "project_provider_load_failed": "Nepodařilo se načíst projekt",
   "project_panel_pkg_load_error": "Nepodařilo se načíst knihovny",
   "project_panel_pkg_versions_error": "Nepodařilo se načíst verze knihovny",
@@ -235,6 +236,14 @@
   "editor_jacly_autosave_error": "Nepodařilo se uložit automatickou zálohu projektu",
   "editor_jacly_save_json_error": "Nepodařilo se uložit JSON",
   "editor_jacly_save_code_error": "Nepodařilo se uložit generovaný kód",
+  "editor_jacly_recovery_title": "Soubor bloků je poškozený",
+  "editor_jacly_recovery_description": "Jacly našel platnou zálohu ({backupName}). Nahradit poškozený soubor index.jacly touto zálohou? Poškozený soubor bude zachován.",
+  "editor_jacly_recovery_keep": "Ponechat poškozený soubor",
+  "editor_jacly_recovery_replace": "Nahradit ze zálohy",
+  "editor_jacly_recovery_restoring": "Obnovuji...",
+  "editor_jacly_recovery_kept": "Poškozený soubor index.jacly nebyl změněn",
+  "editor_jacly_recovery_success": "Soubor index.jacly byl obnoven ze zálohy",
+  "editor_jacly_recovery_error": "Obnovení souboru index.jacly ze zálohy se nezdařilo",
   "editor_jacly_missing_packages": "Některé bloky ve vašem workspace vyžadují balíčky, které nejsou aktuálně nainstalovány. Zkontrolujte chybějící balíčky a nainstalujte je.",
   "editor_jacly_loading_desc": "Připravuji váš workspace...",
   "editor_jacly_installing_header": "Instalace balíčků",

apps/web/messages/en.json

@@ -234,6 +234,14 @@
   "editor_jacly_autosave_error": "Failed to save project autosave backup",
   "editor_jacly_save_json_error": "Failed to save JSON",
   "editor_jacly_save_code_error": "Failed to save generated code",
+  "editor_jacly_recovery_title": "The blocks file is damaged",
+  "editor_jacly_recovery_description": "Jacly found a valid backup ({backupName}). Replace the damaged index.jacly file with this backup? The damaged file will be preserved.",
+  "editor_jacly_recovery_keep": "Keep damaged file",
+  "editor_jacly_recovery_replace": "Replace from backup",
+  "editor_jacly_recovery_restoring": "Restoring...",
+  "editor_jacly_recovery_kept": "The damaged index.jacly file was not changed",
+  "editor_jacly_recovery_success": "index.jacly was restored from backup",
+  "editor_jacly_recovery_error": "Failed to restore index.jacly from backup",
   "editor_jacly_missing_packages": "Some blocks in your workspace require packages that are not currently installed. Please review the missing packages and install them.",
   "editor_jacly_loading_desc": "Preparing your workspace...",
   "editor_jacly_installing_header": "Installing Packages",
@@ -242,6 +250,7 @@
   "editor_code_file_update_error": "Error updating file",
   "project_download_no_files": "No files found in project to download",
   "project_layout_load_error": "Failed to load layout settings, using default",
+  "project_save_before_leave_error": "Failed to save project files. Navigation was stopped to protect your changes.",
   "device_wifi_network_added": "WiFi network added successfully",
   "device_wifi_network_add_failed": "Failed to add WiFi network",
   "device_wifi_network_removed": "WiFi network removed successfully",

apps/web/src/editor/code/code-editor-rw.tsx

@@ -20,6 +20,7 @@ export function CodeEditorRW({ filePath }: CodeEditorRWProps) {
   const fullPath = `${projectPath}/${filePath}`;
 
   useEffect(() => {
+    setLoading(true);
     async function loadFile() {
       if (!monacoService) return;
       await monacoService.requestFile(filePath);
@@ -29,14 +30,9 @@ export function CodeEditorRW({ filePath }: CodeEditorRWProps) {
     loadFile();
 
     return () => {
-      monacoService?.closeFile(filePath);
+      void monacoService?.closeFile(filePath);
     };
-  }, [fullPath]);
-
-  function handleEditorChange(value: string | undefined) {
-    if (value === undefined) return;
-    monacoService?.updateFile(filePath, value);
-  }
+  }, [filePath, monacoService]);
 
   if (loading) {
     return <div>{m.editor_loading()}</div>;
@@ -53,7 +49,6 @@ export function CodeEditorRW({ filePath }: CodeEditorRWProps) {
         automaticLayout: true,
         fixedOverflowWidgets: true,
       }}
-      onChange={handleEditorChange}
     />
   );
 }

apps/web/src/editor/jacly/index.ts

@@ -1,5 +1,12 @@
 export { JaclyEditorComponent } from './jacly';
-export { AUTOSAVE_INTERVAL_MS, writeAutosaveBackup, writeStartupBackup } from './jacly-backup';
+export {
+  AUTOSAVE_INTERVAL_MS,
+  preserveCorruptIndex,
+  writeAutosaveBackup,
+  writeStartupBackup,
+} from './jacly-backup';
+export type { JaclyBackupCandidate } from './jacly-backup-recovery';
+export { findNewestValidBackup } from './jacly-backup-recovery';
 export type {
   EditorJaclyActions,
   EditorJaclyContextValue,
@@ -17,4 +24,3 @@ export {
 export { JaclyEditorPanel } from './jacly-panel';
 export { EditorJaclyProvider } from './jacly-provider';
 export { jaclySaveCoordinator } from './jacly-save-coordinator';
-export { createLatestFileWriter, type LatestFileWriter } from './latest-file-writer';

apps/web/src/editor/jacly/jacly-backup-recovery.ts

@@ -0,0 +1,54 @@
+import { basename, extname, join } from 'node:path';
+import type { ProjectFsPromises } from './jacly-files';
+
+const BACKUP_DIR = 'backup';
+
+export interface JaclyBackupCandidate {
+  path: string;
+  name: string;
+  content: string;
+  json: object;
+}
+
+export async function findNewestValidBackup(
+  fsp: ProjectFsPromises,
+  projectPath: string,
+  jaclyPath: string,
+): Promise<JaclyBackupCandidate | null> {
+  const name = basename(jaclyPath, extname(jaclyPath));
+  const ext = extname(jaclyPath);
+  const backupDir = join(projectPath, BACKUP_DIR);
+
+  try {
+    const files = (await fsp.readdir(backupDir)) as string[];
+    const candidates = await Promise.all(
+      files
+        .filter(
+          (file) =>
+            (file.startsWith(`${name}-A-`) || file.startsWith(`${name}-S-`)) && file.endsWith(ext),
+        )
+        .map(async (file) => ({
+          file,
+          mtimeMs: (await fsp.stat(join(backupDir, file))).mtimeMs,
+        })),
+    );
+    candidates.sort((left, right) => right.mtimeMs - left.mtimeMs);
+
+    for (const { file } of candidates) {
+      const path = join(backupDir, file);
+      try {
+        const content = await fsp.readFile(path, 'utf-8');
+        const json: unknown = JSON.parse(content);
+        if (typeof json === 'object' && json !== null && !Array.isArray(json)) {
+          return { path, name: file, content, json };
+        }
+      } catch {
+        // Continue to older backups when a backup is incomplete or invalid.
+      }
+    }
+  } catch {
+    return null;
+  }
+
+  return null;
+}

apps/web/src/editor/jacly/jacly-backup.ts

@@ -1,4 +1,5 @@
 import { basename, extname, join } from 'node:path';
+import { durableWriteFile } from '@/project';
 import type { ProjectFsPromises } from './jacly-files';
 
 export const AUTOSAVE_INTERVAL_MS = 5 * 60 * 1000;
@@ -19,7 +20,7 @@ async function writeBackupFile(
   projectPath: string,
   jaclyPath: string,
   content: string,
-  prefix: 'S' | 'A',
+  prefix: 'S' | 'A' | 'C',
 ): Promise<void> {
   const name = basename(jaclyPath, extname(jaclyPath));
   const ext = extname(jaclyPath);
@@ -28,7 +29,16 @@ async function writeBackupFile(
   await fsp.mkdir(backupDir, { recursive: true });
 
   const fileName = `${name}-${prefix}-${formatTimestamp(new Date())}${ext}`;
-  await fsp.writeFile(join(backupDir, fileName), content, 'utf-8');
+  await durableWriteFile(fsp, join(backupDir, fileName), content);
+}
+
+export async function preserveCorruptIndex(
+  fsp: ProjectFsPromises,
+  projectPath: string,
+  jaclyPath: string,
+  content: string,
+): Promise<void> {
+  await writeBackupFile(fsp, projectPath, jaclyPath, content, 'C');
 }
 
 async function pruneAutosaveBackups(

apps/web/src/editor/jacly/jacly-files.ts

@@ -16,13 +16,14 @@ export async function readOrCreateJsonFile(
   fs: ProjectFs,
   fsp: ProjectFsPromises,
   filePath: string,
+  createFile: (path: string, content: string) => Promise<void>,
 ): Promise<object> {
   await ensureParentDir(fsp, filePath);
 
   if (fs.existsSync(filePath)) {
     return JSON.parse(fs.readFileSync(filePath, 'utf-8'));
   }
 
-  await fsp.writeFile(filePath, '{}', 'utf-8');
+  await createFile(filePath, '{}');
   return {};
 }