fix offline mode and layout bugs

src/lib/services/offlineCatalog.ts

@@ -0,0 +1,102 @@
+// Offline catalog service - "browse & queue" for offline mode.
+//
+// Two responsibilities:
+//  1. Full-catalog pre-sync: while online, walk every library and persist all
+//     items to the offline cache so the whole catalog is browsable (greyed out)
+//     offline. Backed by the `syncFullCatalog` Rust command.
+//  2. Resume-on-reconnect: when the server becomes reachable again, resolve the
+//     stream URLs of downloads that were queued while offline and let the pump
+//     start them. Backed by `resumeQueuedDownloads`.
+//
+// It also owns the `showServerCatalog` UI flag (the offline banner toggle that
+// reveals greyed-out, non-downloaded server media).
+//
+// TRACES: UR-002
+
+import { writable, type Writable } from "svelte/store";
+import { commands } from "$lib/api/bindings";
+import { auth } from "$lib/stores/auth";
+
+/**
+ * When true (and offline), library grids reveal greyed-out versions of media
+ * that exists on the server but isn't downloaded, each with a button to queue
+ * a download for the next reconnect. Toggled from the offline banner.
+ */
+export const showServerCatalog: Writable<boolean> = writable(false);
+
+/** Last time a full catalog sync completed, for a UI hint. */
+export const lastCatalogSync: Writable<string | null> = writable(null);
+
+// Guard against overlapping syncs (they can be slow on large libraries).
+let syncInProgress = false;
+
+function currentHandle(): string | null {
+  try {
+    return auth.getRepository().getHandle();
+  } catch {
+    return null; // not connected yet
+  }
+}
+
+/**
+ * Walk every library and cache the full catalog. Best-effort and non-blocking:
+ * safe to call on startup (while online) and on reconnect. No-ops if not
+ * connected or a sync is already running.
+ */
+export async function syncCatalog(): Promise<void> {
+  if (syncInProgress) return;
+  const handle = currentHandle();
+  if (!handle) return;
+
+  syncInProgress = true;
+  try {
+    const result = await commands.syncFullCatalog(handle);
+    console.info(
+      `[OfflineCatalog] Synced ${result.itemsCached} items (${result.librariesFailed} libraries failed)`
+    );
+    await refreshSyncStatus();
+  } catch (err) {
+    console.warn("[OfflineCatalog] Full catalog sync failed:", err);
+  } finally {
+    syncInProgress = false;
+  }
+}
+
+/**
+ * Resolve URLs for downloads queued while offline and pump them. Call on
+ * reconnect. No-ops if not connected.
+ */
+export async function resumeQueued(): Promise<void> {
+  const handle = currentHandle();
+  if (!handle) return;
+  try {
+    const result = await commands.resumeQueuedDownloads(handle);
+    if (result.resolved > 0 || result.failed > 0) {
+      console.info(
+        `[OfflineCatalog] Resumed queued downloads: ${result.resolved} resolved, ${result.failed} failed`
+      );
+    }
+  } catch (err) {
+    console.warn("[OfflineCatalog] Failed to resume queued downloads:", err);
+  }
+}
+
+/** Refresh the last-synced timestamp from the backend. */
+export async function refreshSyncStatus(): Promise<void> {
+  try {
+    const status = await commands.catalogSyncStatus();
+    lastCatalogSync.set(status.lastSyncedAt ?? null);
+  } catch (err) {
+    console.debug("[OfflineCatalog] Failed to fetch sync status:", err);
+  }
+}
+
+/**
+ * Called when the server becomes reachable again: resume queued downloads first
+ * (fast, user-visible), then refresh the catalog in the background.
+ */
+export async function onReconnected(): Promise<void> {
+  await resumeQueued();
+  // Fire-and-forget: don't block reconnection handling on a potentially long walk.
+  void syncCatalog();
+}