Panel busy states: Connecting placeholder with Cancel, slow-load overlay

Connecting blanks the list to a fading spinner with the target name and
a Cancel button (token discards late results and orphan sessions).
Listings >300ms dim the list under a spinner. All panel input is
blocked while busy; the source picker stays usable.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

ui/src/app/file-panel/file-panel.html

@@ -156,8 +156,9 @@
 <div class="flex items-center gap-1 border-b border-border px-2 py-1.5">
   <button
     (click)="panel().up()"
+    [disabled]="blocked()"
     title="Parent directory (Backspace)"
-    class="grid size-(--path-ctl-h) shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-foreground"
+    class="grid size-(--path-ctl-h) shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-foreground disabled:opacity-50 disabled:hover:bg-transparent"
   >
     <ng-icon name="mynaArrowUp" size="1rem" />
   </button>
@@ -167,13 +168,15 @@
     (keydown.enter)="commitPath()"
     (keydown.escape)="resetPath()"
     (keydown)="$event.stopPropagation()"
+    [disabled]="blocked()"
     spellcheck="false"
-    class="h-(--path-ctl-h) min-w-0 flex-1 rounded-md border border-input bg-transparent px-2 font-mono text-(length:--path-font) outline-none focus:ring-2 focus:ring-ring"
+    class="h-(--path-ctl-h) min-w-0 flex-1 rounded-md border border-input bg-transparent px-2 font-mono text-(length:--path-font) outline-none focus:ring-2 focus:ring-ring disabled:opacity-50"
   />
   <button
     (click)="panel().refresh()"
+    [disabled]="blocked()"
     title="Refresh"
-    class="grid size-(--path-ctl-h) shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-foreground"
+    class="grid size-(--path-ctl-h) shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-foreground disabled:opacity-50 disabled:hover:bg-transparent"
   >
     @if (panel().loading()) {
       <ng-icon name="mynaSpinner" size="1rem" class="animate-spin" />
@@ -217,14 +220,31 @@
 }
 
 <!-- file list -->
+<div class="relative min-h-0 flex-1">
 <div
   #list
   tabindex="0"
   (keydown)="onKeydown($event)"
   (mousedown)="activate()"
   (contextmenu)="listContextMenu($event)"
-  class="flex-1 overflow-y-auto outline-none"
+  class="h-full overflow-y-auto outline-none"
 >
+  @if (panel().connecting()) {
+    <div class="panel-fade-in grid h-full place-items-center">
+      <div class="flex flex-col items-center gap-3">
+        <ng-icon name="mynaSpinner" size="1.4rem" class="animate-spin text-primary" />
+        <span class="text-xs text-muted-foreground">
+          Connecting to {{ panel().connectingTo() }}…
+        </span>
+        <button
+          (click)="cancelConnect()"
+          class="rounded-md border border-border px-3 py-1 text-xs text-muted-foreground hover:bg-accent hover:text-foreground"
+        >
+          Cancel
+        </button>
+      </div>
+    </div>
+  } @else {
   @for (entry of panel().sorted(); track entry.name; let i = $index) {
     <div
       [attr.data-index]="i"
@@ -255,4 +275,11 @@
   @if (panel().filter() && filterMatches() === 0) {
     <div class="p-6 text-center text-xs text-muted-foreground">No matches</div>
   }
+  }
+</div>
+@if (panel().slowLoad() && !panel().connecting()) {
+  <div class="panel-fade-in absolute inset-0 z-10 grid place-items-center bg-background/60">
+    <ng-icon name="mynaSpinner" size="1.4rem" class="animate-spin text-primary" />
+  </div>
+}
 </div>

ui/src/app/file-panel/file-panel.ts

@@ -37,6 +37,8 @@ export class FilePanel {
   readonly panel = computed(() => this.panels.get(this.side()));
   readonly isActive = computed(() => this.panels.activeSide() === this.side());
   readonly isRemote = computed(() => this.panel().sessionId() !== 'local');
+  /** Input is ignored while the panel is connecting or a listing is in flight. */
+  readonly blocked = computed(() => this.panel().busy());
   /** The copy button points toward the other panel. */
   readonly copyIcon = computed(() => (this.side() === 'left' ? 'mynaArrowRight' : 'mynaArrowLeft'));
 
@@ -63,12 +65,18 @@ export class FilePanel {
     this.panels.setActiveSide(this.side());
   }
 
+  cancelConnect(): void {
+    this.panels.cancelConnect(this.side());
+  }
+
   copyToOther(): void {
+    if (this.blocked()) return;
     this.activate();
     void this.transfers.copyToOtherPanel(this.side());
   }
 
   run(action: 'edit' | 'rename' | 'mkdir' | 'createFile' | 'chmod' | 'delete'): void {
+    if (this.blocked()) return;
     this.activate();
     void this.actions[action](this.panel());
   }
@@ -148,6 +156,7 @@ export class FilePanel {
   }
 
   commitPath(): void {
+    if (this.blocked()) return;
     const value = this.pathDraft().trim();
     if (value) void this.panel().load(value);
     this.listEl().nativeElement.focus();
@@ -159,6 +168,7 @@ export class FilePanel {
   }
 
   rowClick(event: MouseEvent, index: number): void {
+    if (this.blocked()) return;
     this.activate();
     const panel = this.panel();
     if (event.shiftKey) {
@@ -176,6 +186,7 @@ export class FilePanel {
   rowContextMenu(event: MouseEvent, index: number): void {
     event.preventDefault();
     event.stopPropagation();
+    if (this.blocked()) return;
     this.activate();
     const panel = this.panel();
     const entry = panel.sorted()[index] ?? null;
@@ -187,16 +198,19 @@ export class FilePanel {
 
   listContextMenu(event: MouseEvent): void {
     event.preventDefault();
+    if (this.blocked()) return;
     this.activate();
     void this.actions.openContextMenu({ side: this.side(), panel: this.panel(), entry: null });
   }
 
   openAt(index: number): void {
+    if (this.blocked()) return;
     const entry = this.panel().sorted()[index];
     if (entry) this.panel().open(entry);
   }
 
   onKeydown(event: KeyboardEvent): void {
+    if (this.blocked()) return;
     const panel = this.panel();
     const key = event.key;
 

ui/src/app/panels.service.ts

@@ -17,9 +17,18 @@ export class PanelState {
   readonly fsKey = signal('local');
   readonly title = signal('Local');
   readonly connecting = signal(false);
+  /** Name shown in the "Connecting to X…" placeholder while connecting. */
+  readonly connectingTo = signal<string | null>(null);
   readonly cwd = signal('');
   readonly entries = signal<FileEntry[]>([]);
   readonly loading = signal(false);
+  /** True once an in-flight load has taken >300ms — drives the dim overlay. */
+  readonly slowLoad = signal(false);
+  /** Bumping this discards the result of any in-flight connect (cancel/supersede). */
+  connectToken = 0;
+
+  /** Input on this panel is ignored while it's connecting or loading. */
+  readonly busy = computed(() => this.connecting() || this.loading());
   readonly sortKey = signal<SortKey>('name');
   readonly sortAsc = signal(true);
   readonly cursor = signal(0);
@@ -65,6 +74,7 @@ export class PanelState {
 
   async load(path: string | null): Promise<void> {
     this.loading.set(true);
+    const slowTimer = setTimeout(() => this.slowLoad.set(true), 300);
     try {
       const res = await this.deps.rpc.request.listDir({ sessionId: this.sessionId(), path });
       if (!res.ok) {
@@ -77,6 +87,8 @@ export class PanelState {
       this.selected.set(new Set());
       this.filter.set('');
     } finally {
+      clearTimeout(slowTimer);
+      this.slowLoad.set(false);
       this.loading.set(false);
     }
   }
@@ -86,6 +98,7 @@ export class PanelState {
     const keepCursorName = this.sorted()[this.cursor()]?.name;
     const keepSelected = this.selected();
     this.loading.set(true);
+    const slowTimer = setTimeout(() => this.slowLoad.set(true), 300);
     try {
       const res = await this.deps.rpc.request.listDir({
         sessionId: this.sessionId(),
@@ -102,6 +115,8 @@ export class PanelState {
       const idx = this.sorted().findIndex((e) => e.name === keepCursorName);
       this.cursor.set(idx >= 0 ? idx : Math.min(this.cursor(), Math.max(0, this.sorted().length - 1)));
     } finally {
+      clearTimeout(slowTimer);
+      this.slowLoad.set(false);
       this.loading.set(false);
     }
   }
@@ -349,9 +364,16 @@ export class PanelsService {
   /** Connect a panel to a server; replaces (and disconnects) its previous remote session. */
   async connectPanel(side: Side, config: ConnectionConfig, title: string): Promise<boolean> {
     const panel = this.get(side);
+    const token = ++panel.connectToken;
     panel.connecting.set(true);
+    panel.connectingTo.set(title);
     try {
       const res = await this.rpc.request.connect({ config });
+      if (panel.connectToken !== token) {
+        // cancelled or superseded while waiting — clean up the orphan session
+        if (res.ok) void this.rpc.request.disconnect({ sessionId: res.sessionId });
+        return false;
+      }
       if (!res.ok) {
         this.toast.error(`${title}: ${res.error}`);
         return false;
@@ -366,9 +388,21 @@ export class PanelsService {
       await panel.load(config.initialPath ?? res.homeDir);
       return true;
     } finally {
+      if (panel.connectToken === token) {
         panel.connecting.set(false);
+        panel.connectingTo.set(null);
       }
     }
+  }
+
+  /** Abort waiting on an in-flight connect; the panel keeps its previous state. */
+  cancelConnect(side: Side): void {
+    const panel = this.get(side);
+    if (!panel.connecting()) return;
+    panel.connectToken++;
+    panel.connecting.set(false);
+    panel.connectingTo.set(null);
+  }
 
   async disconnectPanel(side: Side): Promise<void> {
     const panel = this.get(side);

ui/src/styles.css

@@ -188,6 +188,16 @@
   --action-icon: 1.05rem;
 }
 
+/* Soft entrance for the panel busy states (connecting placeholder, load overlay). */
+@keyframes panel-fade-in {
+  from {
+    opacity: 0;
+  }
+}
+.panel-fade-in {
+  animation: panel-fade-in 0.18s ease-out;
+}
+
 /* Accent tone (data-accent set by SettingsService; absent = graphite/zinc).
    Each tone is one hue+chroma line; the formula blocks below derive --primary,
    --ring and the cursor-row tint for light and both dark states. The dark