enhance playlist addition cancellation and improve error handling UI

app/ytdl.py

@@ -535,10 +535,10 @@ class DownloadQueue:
         self.active_downloads = set()
         self.semaphore = asyncio.Semaphore(int(self.config.MAX_CONCURRENT_DOWNLOADS))
         self.done.load()
-        self._add_canceled = False
+        self._add_generation = 0
 
     def cancel_add(self):
-        self._add_canceled = True
+        self._add_generation += 1
         log.info('Playlist add operation canceled by user')
 
     async def __import_queue(self):
@@ -660,6 +660,7 @@ class DownloadQueue:
         subtitle_language,
         subtitle_mode,
         already,
+        _add_gen=None,
     ):
         if not entry:
             return {'status': 'error', 'msg': "Invalid/empty data was given."}
@@ -690,6 +691,7 @@ class DownloadQueue:
                 subtitle_language,
                 subtitle_mode,
                 already,
+                _add_gen,
             )
         elif etype == 'playlist' or etype == 'channel':
             log.debug(f'Processing as a {etype}')
@@ -704,7 +706,7 @@ class DownloadQueue:
                 log.info(f'Item limit is set. Processing only first {playlist_item_limit} entries')
                 entries = entries[:playlist_item_limit]
             for index, etr in enumerate(entries, start=1):
-                if self._add_canceled:
+                if _add_gen is not None and self._add_generation != _add_gen:
                     log.info(f'Playlist add canceled after processing {len(already)} entries')
                     return {'status': 'ok', 'msg': f'Canceled - added {len(already)} items before cancel'}
                 etr["_type"] = "video"
@@ -728,6 +730,7 @@ class DownloadQueue:
                         subtitle_language,
                         subtitle_mode,
                         already,
+                        _add_gen,
                     )
                 )
             if any(res['status'] == 'error' for res in results):
@@ -773,6 +776,7 @@ class DownloadQueue:
         subtitle_language="en",
         subtitle_mode="prefer_manual",
         already=None,
+        _add_gen=None,
     ):
         log.info(
             f'adding {url}: {quality=} {format=} {already=} {folder=} {custom_name_prefix=} '
@@ -780,7 +784,7 @@ class DownloadQueue:
             f'{subtitle_format=} {subtitle_language=} {subtitle_mode=}'
         )
         if already is None:
-            self._add_canceled = False
+            _add_gen = self._add_generation
         already = set() if already is None else already
         if url in already:
             log.info('recursion detected, skipping')
@@ -805,6 +809,7 @@ class DownloadQueue:
             subtitle_language,
             subtitle_mode,
             already,
+            _add_gen,
         )
 
     async def start_pending(self, ids):

ui/src/app/app.html

@@ -98,7 +98,12 @@
               name="addUrl"
               [(ngModel)]="addUrl"
               [disabled]="addInProgress || downloads.loading">
-            @if (addInProgress) {
+            @if (addInProgress && cancelRequested) {
+              <button class="btn btn-warning btn-lg px-3" type="button" disabled>
+                <span class="spinner-border spinner-border-sm me-1" role="status"></span>
+                Canceling...
+              </button>
+            } @else if (addInProgress) {
               <button class="btn btn-danger btn-lg px-3" type="button" (click)="cancelAdding()">
                 <fa-icon [icon]="faTimesCircle" class="me-1" /> Cancel
               </button>
@@ -426,15 +431,9 @@
     </table>
   </div>
 
-  <div class="metube-section-header d-flex align-items-center">
+  <div class="metube-section-header">Completed</div>
-    Completed
-    <button type="button" class="btn btn-sm btn-outline-secondary ms-3"
-      (click)="toggleSortOrder()"
-      ngbTooltip="{{ sortAscending ? 'Oldest first' : 'Newest first' }}">
-      <fa-icon [icon]="sortAscending ? faSortAmountUp : faSortAmountDown" />
-    </button>
-  </div>
   <div class="px-2 py-3 border-bottom">
+    <button type="button" class="btn btn-link text-decoration-none px-0 me-4" (click)="toggleSortOrder()" ngbTooltip="{{ sortAscending ? 'Oldest first' : 'Newest first' }}"><fa-icon [icon]="sortAscending ? faSortAmountUp : faSortAmountDown" />&nbsp; {{ sortAscending ? 'Oldest first' : 'Newest first' }}</button>
     <button type="button" class="btn btn-link text-decoration-none px-0 me-4" disabled #doneDelSelected (click)="delSelectedDownloads('done')"><fa-icon [icon]="faTrashAlt" />&nbsp; Clear selected</button>
     <button type="button" class="btn btn-link text-decoration-none px-0 me-4" disabled #doneClearCompleted (click)="clearCompletedDownloads()"><fa-icon [icon]="faCheckCircle" />&nbsp; Clear completed</button>
     <button type="button" class="btn btn-link text-decoration-none px-0 me-4" disabled #doneClearFailed (click)="clearFailedDownloads()"><fa-icon [icon]="faTimesCircle" />&nbsp; Clear failed</button>
@@ -454,7 +453,7 @@
         </tr>
       </thead>
       <tbody>
-        @for (entry of sortedDone(); track entry[1].id) {
+        @for (entry of cachedSortedDone; track entry[1].id) {
           <tr [class.disabled]='entry[1].deleting'>
             <td>
               <app-slave-checkbox [id]="entry[0]" [master]="doneMasterCheckboxRef" [checkable]="entry[1]" />
@@ -465,7 +464,12 @@
                   <fa-icon [icon]="faCheckCircle" class="text-success" />
                 }
                 @if (entry[1].status === 'error') {
-                  <fa-icon [icon]="faTimesCircle" class="text-danger" style="cursor: pointer;" (click)="toggleErrorDetail(entry[0])" />
+                  <button type="button" class="btn btn-link p-0"
+                    (click)="toggleErrorDetail(entry[0])"
+                    [attr.aria-label]="'Toggle error details for ' + entry[1].title"
+                    [attr.aria-expanded]="isErrorExpanded(entry[0])">
+                    <fa-icon [icon]="faTimesCircle" class="text-danger" />
+                  </button>
                 }
               </div>
               <span ngbTooltip="{{buildResultItemTooltip(entry[1])}}">@if (!!entry[1].filename) {
@@ -494,9 +498,13 @@
                       <div class="text-muted" style="word-break: break-all;"><strong>URL:</strong> {{entry[1].url}}</div>
                     </div>
                     <button type="button" class="btn btn-sm btn-outline-danger ms-2 flex-shrink-0"
-                      (click)="copyErrorMessage(entry[1]); $event.stopPropagation()"
+                      (click)="copyErrorMessage(entry[0], entry[1]); $event.stopPropagation()"
                       ngbTooltip="Copy error details to clipboard">
+                      @if (lastCopiedErrorId === entry[0]) {
+                        <span class="text-success">Copied!</span>
+                      } @else {
                         <fa-icon [icon]="faCopy" />
+                      }
                     </button>
                   </div>
                 </div>

ui/src/app/app.ts

@@ -53,6 +53,7 @@ export class App implements AfterViewInit, OnInit {
   subtitleLanguage: string;
   subtitleMode: string;
   addInProgress = false;
+  cancelRequested = false;
   themes: Theme[] = Themes;
   activeTheme: Theme | undefined;
   customDirs$!: Observable<string[]>;
@@ -68,6 +69,8 @@ export class App implements AfterViewInit, OnInit {
   isAdvancedOpen = false;
   sortAscending = false;
   expandedErrors: Set<string> = new Set();
+  cachedSortedDone: [string, Download][] = [];
+  lastCopiedErrorId: string | null = null;
 
   // Download metrics
   activeDownloads = 0;
@@ -193,6 +196,7 @@ export class App implements AfterViewInit, OnInit {
     });
     this.downloads.doneChanged.subscribe(() => {
       this.updateMetrics();
+      this.rebuildSortedDone();
     });
     // Subscribe to real-time updates
     this.downloads.updated.subscribe(() => {
@@ -423,20 +427,24 @@ export class App implements AfterViewInit, OnInit {
 
     console.debug('Downloading: url=' + url + ' quality=' + quality + ' format=' + format + ' folder=' + folder + ' customNamePrefix=' + customNamePrefix + ' playlistItemLimit=' + playlistItemLimit + ' autoStart=' + autoStart + ' splitByChapters=' + splitByChapters + ' chapterTemplate=' + chapterTemplate + ' subtitleFormat=' + subtitleFormat + ' subtitleLanguage=' + subtitleLanguage + ' subtitleMode=' + subtitleMode);
     this.addInProgress = true;
+    this.cancelRequested = false;
     this.downloads.add(url, quality, format, folder, customNamePrefix, playlistItemLimit, autoStart, splitByChapters, chapterTemplate, subtitleFormat, subtitleLanguage, subtitleMode).subscribe((status: Status) => {
-      if (status.status === 'error') {
+      if (status.status === 'error' && !this.cancelRequested) {
         alert(`Error adding URL: ${status.msg}`);
-      } else {
+      } else if (status.status !== 'error') {
         this.addUrl = '';
       }
       this.addInProgress = false;
+      this.cancelRequested = false;
     });
   }
 
   cancelAdding() {
+    this.cancelRequested = true;
     this.downloads.cancelAdd().subscribe({
-      next: () => { this.addInProgress = false; },
+      error: (err) => {
-      error: () => { this.addInProgress = false; }
+        console.error('Failed to cancel adding:', err?.message || err);
+      }
     });
   }
 
@@ -715,20 +723,18 @@ export class App implements AfterViewInit, OnInit {
   toggleSortOrder() {
     this.sortAscending = !this.sortAscending;
     this.cookieService.set('metube_sort_ascending', this.sortAscending ? 'true' : 'false', { expires: 3650 });
+    this.rebuildSortedDone();
   }
 
-  sortedDone(): [string, Download][] {
+  private rebuildSortedDone() {
     const result: [string, Download][] = [];
     this.downloads.done.forEach((dl, key) => {
       result.push([key, dl]);
     });
-    result.sort((a, b) => {
+    if (!this.sortAscending) {
-      const tsA = (a[1] as any).timestamp || 0;
+      result.reverse();
-      const tsB = (b[1] as any).timestamp || 0;
+    }
-      const cmp = tsA < tsB ? -1 : tsA > tsB ? 1 : 0;
+    this.cachedSortedDone = result;
-      return this.sortAscending ? cmp : -cmp;
-    });
-    return result;
   }
 
   toggleErrorDetail(id: string) {
@@ -736,13 +742,40 @@ export class App implements AfterViewInit, OnInit {
     else this.expandedErrors.add(id);
   }
 
-  copyErrorMessage(download: Download) {
+  copyErrorMessage(id: string, download: Download) {
     const parts: string[] = [];
     if (download.title) parts.push(`Title: ${download.title}`);
     if (download.url) parts.push(`URL: ${download.url}`);
     if (download.msg) parts.push(`Message: ${download.msg}`);
     if (download.error) parts.push(`Error: ${download.error}`);
-    navigator.clipboard.writeText(parts.join('\n')).catch(() => {});
+    const text = parts.join('\n');
+    if (!text.trim()) return;
+    const done = () => {
+      this.lastCopiedErrorId = id;
+      setTimeout(() => { this.lastCopiedErrorId = null; }, 1500);
+    };
+    const fail = (err?: unknown) => {
+      console.error('Clipboard write failed:', err);
+      alert('Failed to copy to clipboard. Your browser may require HTTPS for clipboard access.');
+    };
+    if (navigator.clipboard?.writeText) {
+      navigator.clipboard.writeText(text).then(done).catch(fail);
+    } else {
+      try {
+        const ta = document.createElement('textarea');
+        ta.value = text;
+        ta.setAttribute('readonly', '');
+        ta.style.position = 'fixed';
+        ta.style.opacity = '0';
+        document.body.appendChild(ta);
+        ta.select();
+        document.execCommand('copy');
+        document.body.removeChild(ta);
+        done();
+      } catch (e) {
+        fail(e);
+      }
+    }
   }
 
   isErrorExpanded(id: string): boolean {

ui/src/app/services/downloads.service.ts

@@ -209,7 +209,7 @@ export class DownloadsService {
     return Array.from(this.queue.values()).map(download => download.url);
   }
   public cancelAdd() {
-    return this.http.post<any>('cancel-add', {}).pipe(
+    return this.http.post<Status>('cancel-add', {}).pipe(
       catchError(this.handleHTTPError)
     );
   }