Fix note sync reliability and Unicode filename support

- Fixed critical bug where notes with empty category had malformed IDs (leading slash)
- Added URL encoding for Czech and Unicode characters in WebDAV paths
- Fixed filename sanitization to preserve Unicode characters (only remove filesystem-unsafe chars)
- Updated note preview to show first non-empty line after title instead of repeating title
- Adjusted default column widths for better proportions (increased window width to 1300px)
- Protection mechanism now works correctly with proper note ID matching

src-tauri/tauri.conf.json

@@ -13,9 +13,9 @@
     "windows": [
       {
         "title": "Nextcloud Notes",
-        "width": 1200,
+        "width": 1300,
         "height": 800,
-        "minWidth": 900,
+        "minWidth": 800,
         "minHeight": 600,
         "devtools": true
       }

src/App.tsx

@@ -212,16 +212,7 @@ function App() {
 
   const handleCreateNote = async () => {
     try {
-      const timestamp = new Date().toLocaleString('en-US', {
+      const note = await syncManager.createNote('New Note', '', selectedCategory);
-        year: 'numeric',
-        month: '2-digit',
-        day: '2-digit',
-        hour: '2-digit',
-        minute: '2-digit',
-        hour12: false,
-      }).replace(/[/:]/g, '-').replace(', ', ' ');
-      
-      const note = await syncManager.createNote(`New Note ${timestamp}`, '', selectedCategory);
       setNotes([note, ...notes]);
       setSelectedNoteId(note.id);
     } catch (error) {
@@ -275,12 +266,24 @@ function App() {
             favorite: updatedNote.favorite,
           });
           setNotes(notes.map(n => n.id === originalNote.id ? finalNote : n.id === movedNote.id ? finalNote : n));
+          // Update selected note ID if it changed
+          if (selectedNoteId === originalNote.id && finalNote.id !== originalNote.id) {
+            setSelectedNoteId(finalNote.id);
+          }
         } else {
           setNotes(notes.map(n => n.id === originalNote.id ? movedNote : n));
+          // Update selected note ID if it changed
+          if (selectedNoteId === originalNote.id && movedNote.id !== originalNote.id) {
+            setSelectedNoteId(movedNote.id);
+          }
         }
       } else {
         const updated = await syncManager.updateNote(updatedNote);
         setNotes(notes.map(n => n.id === updatedNote.id ? updated : n));
+        // Update selected note ID if it changed (e.g., filename changed due to first line edit)
+        if (selectedNoteId === updatedNote.id && updated.id !== updatedNote.id) {
+          setSelectedNoteId(updated.id);
+        }
       }
     } catch (error) {
       console.error('Update note failed:', error);

src/api/nextcloud.ts

@@ -259,7 +259,7 @@ export class NextcloudAPI {
     const title = firstLine || filename.replace(/\.(md|txt)$/, '');
     
     return {
-      id: `${category}/${filename}`,
+      id: category ? `${category}/${filename}` : filename,
       filename,
       path: category ? `${category}/${filename}` : filename,
       etag,
@@ -358,7 +358,7 @@ export class NextcloudAPI {
   async fetchNoteContentWebDAV(note: Note): Promise<Note> {
     const categoryPath = note.category ? `/${note.category}` : '';
     const filename = note.filename || String(note.id).split('/').pop() || 'note.md';
-    const webdavPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${filename}`;
+    const webdavPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${encodeURIComponent(filename)}`;
     const url = `${this.serverURL}${webdavPath}`;
     
     const response = await tauriFetch(url, {
@@ -374,9 +374,9 @@ export class NextcloudAPI {
   }
 
   async createNoteWebDAV(title: string, content: string, category: string): Promise<Note> {
-    const filename = `${title.replace(/[^a-zA-Z0-9\s-]/g, '').replace(/\s+/g, ' ').trim()}.md`;
+    const filename = `${title.replace(/[\/:\*?"<>|]/g, '').replace(/\s+/g, ' ').trim()}.md`;
     const categoryPath = category ? `/${category}` : '';
-    const webdavPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${filename}`;
+    const webdavPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${encodeURIComponent(filename)}`;
     const url = `${this.serverURL}${webdavPath}`;
     
     // Ensure category directory exists
@@ -411,7 +411,7 @@ export class NextcloudAPI {
     const modified = Math.floor(Date.now() / 1000);
     
     return {
-      id: `${category}/${filename}`,
+      id: category ? `${category}/${filename}` : filename,
       filename,
       path: category ? `${category}/${filename}` : filename,
       etag,
@@ -425,8 +425,28 @@ export class NextcloudAPI {
   }
 
   async updateNoteWebDAV(note: Note): Promise<Note> {
+    // Extract new title from first line of content
+    const firstLine = note.content.split('\n')[0].replace(/^#+\s*/, '').trim();
+    const newTitle = firstLine || 'New Note';
+    const newFilename = `${newTitle.replace(/[\/:\*?"<>|]/g, '').replace(/\s+/g, ' ').trim()}.md`;
+    
+    // Check if filename needs to change
+    const needsRename = note.filename !== newFilename;
+    
+    if (needsRename) {
+      // Rename the file first, then update content
+      const renamedNote = await this.renameNoteWebDAV(note, newFilename);
+      // Now update the content of the renamed file
+      return this.updateNoteContentWebDAV(renamedNote);
+    } else {
+      // Just update content
+      return this.updateNoteContentWebDAV(note);
+    }
+  }
+
+  private async updateNoteContentWebDAV(note: Note): Promise<Note> {
     const categoryPath = note.category ? `/${note.category}` : '';
-    const webdavPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${note.filename}`;
+    const webdavPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${encodeURIComponent(note.filename!)}`;
     const url = `${this.serverURL}${webdavPath}`;
     
     const noteContent = this.formatNoteContent(note);
@@ -457,9 +477,62 @@ export class NextcloudAPI {
     };
   }
 
+  private async renameNoteWebDAV(note: Note, newFilename: string): Promise<Note> {
+    const categoryPath = note.category ? `/${note.category}` : '';
+    const oldPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${encodeURIComponent(note.filename!)}`;
+    const newPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${encodeURIComponent(newFilename)}`;
+    
+    const response = await tauriFetch(`${this.serverURL}${oldPath}`, {
+      method: 'MOVE',
+      headers: {
+        'Authorization': this.authHeader,
+        'Destination': `${this.serverURL}${newPath}`,
+      },
+    });
+
+    if (!response.ok && response.status !== 201 && response.status !== 204) {
+      throw new Error(`Failed to rename note: ${response.status}`);
+    }
+
+    // Also rename attachment folder if it exists
+    const oldNoteIdStr = String(note.id);
+    const oldJustFilename = oldNoteIdStr.split('/').pop() || oldNoteIdStr;
+    const oldFilenameWithoutExt = oldJustFilename.replace(/\.(md|txt)$/, '');
+    const oldSanitizedNoteId = oldFilenameWithoutExt.replace(/[^a-zA-Z0-9_-]/g, '_');
+    const oldAttachmentFolder = `.attachments.${oldSanitizedNoteId}`;
+    
+    const newFilenameWithoutExt = newFilename.replace(/\.(md|txt)$/, '');
+    const newSanitizedNoteId = newFilenameWithoutExt.replace(/[^a-zA-Z0-9_-]/g, '_');
+    const newAttachmentFolder = `.attachments.${newSanitizedNoteId}`;
+    
+    const oldAttachmentPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${oldAttachmentFolder}`;
+    const newAttachmentPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${newAttachmentFolder}`;
+    
+    try {
+      await tauriFetch(`${this.serverURL}${oldAttachmentPath}`, {
+        method: 'MOVE',
+        headers: {
+          'Authorization': this.authHeader,
+          'Destination': `${this.serverURL}${newAttachmentPath}`,
+        },
+      });
+    } catch (e) {
+      // Attachment folder might not exist, that's ok
+    }
+
+    const newId = note.category ? `${note.category}/${newFilename}` : newFilename;
+    
+    return {
+      ...note,
+      id: newId,
+      filename: newFilename,
+      path: note.category ? `${note.category}/${newFilename}` : newFilename,
+    };
+  }
+
   async deleteNoteWebDAV(note: Note): Promise<void> {
     const categoryPath = note.category ? `/${note.category}` : '';
-    const webdavPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${note.filename}`;
+    const webdavPath = `/remote.php/dav/files/${this.username}/Notes${categoryPath}/${encodeURIComponent(note.filename!)}`;
     const url = `${this.serverURL}${webdavPath}`;
     
     const response = await tauriFetch(url, {
@@ -475,8 +548,8 @@ export class NextcloudAPI {
   async moveNoteWebDAV(note: Note, newCategory: string): Promise<Note> {
     const oldCategoryPath = note.category ? `/${note.category}` : '';
     const newCategoryPath = newCategory ? `/${newCategory}` : '';
-    const oldPath = `/remote.php/dav/files/${this.username}/Notes${oldCategoryPath}/${note.filename}`;
+    const oldPath = `/remote.php/dav/files/${this.username}/Notes${oldCategoryPath}/${encodeURIComponent(note.filename!)}`;
-    const newPath = `/remote.php/dav/files/${this.username}/Notes${newCategoryPath}/${note.filename}`;
+    const newPath = `/remote.php/dav/files/${this.username}/Notes${newCategoryPath}/${encodeURIComponent(note.filename!)}`;
     
     // Ensure new category directory exists (including nested subdirectories)
     if (newCategory) {
@@ -547,7 +620,7 @@ export class NextcloudAPI {
       ...note,
       category: newCategory,
       path: newCategory ? `${newCategory}/${note.filename}` : note.filename || '',
-      id: `${newCategory}/${note.filename}`,
+      id: newCategory ? `${newCategory}/${note.filename}` : (note.filename || ''),
     };
   }
 }

src/components/NotesList.tsx

@@ -125,9 +125,17 @@ export function NotesList({
   };
 
   const getPreview = (content: string) => {
-    // grab first 100 characters of note's content, remove markdown syntax from the preview
+    // Skip first line (title) and find first non-empty line
-    const previewContent = content.substring(0, 100);
+    const lines = content.split('\n');
-    const cleanedPreview = previewContent.replace(/[#*`]/g, '');
+    const contentLines = lines.slice(1); // Skip first line
+    
+    // Find first non-empty line
+    const firstContentLine = contentLines.find(line => line.trim().length > 0);
+    if (!firstContentLine) return '';
+    
+    // Take up to 100 characters from the content lines
+    const previewContent = contentLines.join(' ').substring(0, 100);
+    const cleanedPreview = previewContent.replace(/[#*`]/g, '').trim();
     return cleanedPreview;
   };
 
@@ -160,7 +168,7 @@ export function NotesList({
     <div 
       ref={containerRef}
       className="bg-gray-50 dark:bg-gray-900 border-r border-gray-200 dark:border-gray-700 flex flex-col relative flex-shrink-0"
-      style={{ width: `${width}px`, minWidth: '240px', maxWidth: '600px' }}
+      style={{ width: `${width}px`, minWidth: '340px', maxWidth: '600px' }}
     >
       <div className="p-4 border-b border-gray-200 dark:border-gray-700">
         <div className="flex items-center justify-between mb-3">

src/services/syncManager.ts

@@ -10,6 +10,8 @@ export class SyncManager {
   private syncInProgress: boolean = false;
   private statusCallback: ((status: SyncStatus, pendingCount: number) => void) | null = null;
   private syncCompleteCallback: (() => void) | null = null;
+  private recentlyModifiedNotes: Set<number | string> = new Set();
+  private readonly PROTECTION_WINDOW_MS = 10000;
 
   constructor() {
     window.addEventListener('online', () => {
@@ -110,12 +112,15 @@ export class SyncManager {
         }
       }
       
-      // Remove deleted notes from cache
+      // Remove deleted notes from cache (but protect recently modified notes)
       for (const cachedNote of cachedNotes) {
         if (!serverMap.has(cachedNote.id)) {
+          // Don't delete notes that were recently created/updated (race condition protection)
+          if (!this.recentlyModifiedNotes.has(cachedNote.id)) {
             await localDB.deleteNote(cachedNote.id);
           }
         }
+      }
       
       // Sync favorite status from API
       await this.syncFavoriteStatus();
@@ -236,6 +241,10 @@ export class SyncManager {
       this.notifyStatus('syncing', 0);
       const note = await this.api.createNoteWebDAV(title, content, category);
       await localDB.saveNote(note);
+      
+      // Protect this note from being deleted by background sync for a short window
+      this.protectNote(note.id);
+      
       this.notifyStatus('idle', 0);
       
       // Trigger background sync to fetch any other changes
@@ -297,8 +306,19 @@ export class SyncManager {
 
     try {
       this.notifyStatus('syncing', 0);
+      const oldId = note.id;
       const updatedNote = await this.api.updateNoteWebDAV(note);
+      
+      // If the note ID changed (due to filename change), delete the old cache entry
+      if (oldId !== updatedNote.id) {
+        await localDB.deleteNote(oldId);
+      }
+      
       await localDB.saveNote(updatedNote);
+      
+      // Protect this note from being deleted by background sync for a short window
+      this.protectNote(updatedNote.id);
+      
       this.notifyStatus('idle', 0);
       
       // Trigger background sync to fetch any other changes
@@ -349,6 +369,10 @@ export class SyncManager {
       const movedNote = await this.api.moveNoteWebDAV(note, newCategory);
       await localDB.deleteNote(note.id);
       await localDB.saveNote(movedNote);
+      
+      // Protect the moved note from being deleted by background sync
+      this.protectNote(movedNote.id);
+      
       this.notifyStatus('idle', 0);
       
       // Trigger background sync to fetch any other changes
@@ -370,6 +394,14 @@ export class SyncManager {
   getOnlineStatus(): boolean {
     return this.isOnline;
   }
+
+  // Protect a note from being deleted during background sync for a short window
+  private protectNote(noteId: number | string): void {
+    this.recentlyModifiedNotes.add(noteId);
+    setTimeout(() => {
+      this.recentlyModifiedNotes.delete(noteId);
+    }, this.PROTECTION_WINDOW_MS);
+  }
 }
 
 export const syncManager = new SyncManager();