feat: implement prefetching of initial email data

app/[locale]/page.tsx

@@ -650,7 +650,10 @@ export default function Home() {
     }
   }, [initialCheckDone, isAuthenticated, authLoading]);
 
-  // Load mailboxes and emails when authenticated (only if not already loaded)
+  // Fallback fetch for paths that didn't go through login()'s prefetch
+  // (notably checkAuth on page refresh). The prefetch in auth-store/login()
+  // populates mailboxes before this effect first runs, so on the post-login
+  // path this block is a no-op.
   useEffect(() => {
     if (isAuthenticated && client && mailboxes.length === 0) {
       let retryTimer: ReturnType<typeof setTimeout> | null = null;
@@ -658,18 +661,14 @@ export default function Home() {
 
       const loadData = async (attempt = 1) => {
         try {
-          // First fetch mailboxes and quota (inbox will be auto-selected in fetchMailboxes)
           await Promise.all([
             fetchMailboxes(client),
             fetchQuota(client)
           ]);
 
-          // Get the selected mailbox (should be inbox by default)
           const state = useEmailStore.getState();
           const selectedMailboxId = state.selectedMailbox;
 
-          // On first login the server may still be provisioning mailboxes.
-          // Retry a few times with back-off before giving up.
           if (state.mailboxes.length === 0 && attempt <= 5 && !cancelled) {
             const delay = Math.min(1000 * attempt, 5000);
             debug.log('jmap', `[Mailbox] No mailboxes returned (attempt ${attempt}), retrying in ${delay}ms`);
@@ -677,34 +676,13 @@ export default function Home() {
             return;
           }
 
-          // Fetch emails for the selected mailbox
           if (selectedMailboxId) {
             await fetchEmails(client, selectedMailboxId);
           } else {
             await fetchEmails(client);
           }
 
-          // Fetch tag counts
           fetchTagCounts(client);
-
-          // Setup push notifications after successful data load
-          try {
-            // Register state change callback
-            client.onStateChange((change) => handleStateChange(change, client));
-
-            // Start receiving push notifications
-            const pushEnabled = client.setupPushNotifications();
-
-            if (pushEnabled) {
-              setPushConnected(true);
-              debug.log('push', '[Push] Push notifications successfully enabled');
-            } else {
-              debug.log('push', '[Push] Push notifications not available on this server');
-            }
-          } catch (error) {
-            // Push notifications are optional - don't break the app if they fail
-            debug.log('push', '[Push] Failed to setup push notifications:', error);
-          }
         } catch (error) {
           console.error('Error loading email data:', error);
         }
@@ -714,17 +692,33 @@ export default function Home() {
       return () => {
         cancelled = true;
         if (retryTimer) clearTimeout(retryTimer);
-        client.closePushNotifications();
       };
     }
+  }, [isAuthenticated, client, mailboxes.length, fetchMailboxes, fetchEmails, fetchQuota, fetchTagCounts]);
 
-    // Cleanup push notifications on unmount
+  // Push notifications: set up once per client and tear down when the client
-    return () => {
+  // goes away (logout or account switch). Kept separate from the fetch effect
-      if (client) {
+  // above so it still runs when data was prefetched at login time.
-        client.closePushNotifications();
+  useEffect(() => {
+    if (!isAuthenticated || !client) return;
+
+    try {
+      client.onStateChange((change) => handleStateChange(change, client));
+      const pushEnabled = client.setupPushNotifications();
+      if (pushEnabled) {
+        setPushConnected(true);
+        debug.log('push', '[Push] Push notifications successfully enabled');
+      } else {
+        debug.log('push', '[Push] Push notifications not available on this server');
       }
+    } catch (error) {
+      debug.log('push', '[Push] Failed to setup push notifications:', error);
+    }
+
+    return () => {
+      client.closePushNotifications();
     };
-  }, [isAuthenticated, client, mailboxes.length, fetchMailboxes, fetchEmails, fetchQuota, fetchTagCounts, handleStateChange, setPushConnected]);
+  }, [isAuthenticated, client, handleStateChange, setPushConnected]);
 
   // Keep unified mailbox counts in sync when the feature is enabled and more
   // than one account is connected. Runs whenever the set of connected accounts

stores/auth-store.ts

@@ -512,6 +512,15 @@ export const useAuthStore = create<AuthState>()(
             activeAccountId: accountId,
           });
 
+          // Kick off mailbox/quota/email fetches now so they overlap with the
+          // soft-nav + home-page hydration that follows login. Dynamic import
+          // avoids a static circular dep with email-store.
+          import('@/stores/email-store').then(({ useEmailStore }) => {
+            useEmailStore.getState().prefetchInitialData(client).catch((err) => {
+              debug.error('Initial data prefetch failed:', err);
+            });
+          }).catch(() => {});
+
           // Schedule token refresh for TOTP-upgraded sessions
           if (upgradedToOAuth && oauthExpiresIn > 0) {
             scheduleRefresh(oauthExpiresIn, get().refreshAccessToken, accountId);
@@ -709,6 +718,12 @@ export const useAuthStore = create<AuthState>()(
             activeAccountId: accountId,
           });
 
+          import('@/stores/email-store').then(({ useEmailStore }) => {
+            useEmailStore.getState().prefetchInitialData(client).catch((err) => {
+              debug.error('Initial data prefetch failed:', err);
+            });
+          }).catch(() => {});
+
           scheduleRefresh(expires_in, get().refreshAccessToken, accountId);
 
           notifyParent('sso:auth-success', { username });
@@ -841,6 +856,12 @@ export const useAuthStore = create<AuthState>()(
             activeAccountId: accountId,
           });
 
+          import('@/stores/email-store').then(({ useEmailStore }) => {
+            useEmailStore.getState().prefetchInitialData(client).catch((err) => {
+              debug.error('Initial data prefetch failed:', err);
+            });
+          }).catch(() => {});
+
           scheduleRefresh(expires_in, get().refreshAccessToken, accountId);
 
           notifyParent('sso:auth-success', { username });

stores/email-store.ts

@@ -72,6 +72,10 @@ interface EmailStore {
   // JMAP operations
   fetchMailboxes: (client: IJMAPClient) => Promise<void>;
   fetchEmails: (client: IJMAPClient, mailboxId?: string) => Promise<void>;
+  // Eager post-login bootstrap: fires mailboxes/quota/emails so the round-trips
+  // overlap with Next's soft-nav + home-page hydration. Safe to call multiple
+  // times; later calls are no-ops while a prior one is in flight.
+  prefetchInitialData: (client: IJMAPClient) => Promise<void>;
   loadMoreEmails: (client: IJMAPClient) => Promise<void>;
   fetchEmailContent: (client: IJMAPClient, emailId: string) => Promise<Email | null>;
   fetchQuota: (client: IJMAPClient) => Promise<void>;
@@ -350,6 +354,33 @@ export const useEmailStore = create<EmailStore>((set, get) => ({
     }
   },
 
+  prefetchInitialData: async (client) => {
+    // Coalesce overlapping callers (e.g. login() and a slow home-page useEffect
+    // racing for the same fetch). The promise is stashed on the client so we
+    // don't need a separate keyed map and stale entries can't outlive the client.
+    const target = client as IJMAPClient & { __prefetchPromise?: Promise<void> };
+    if (target.__prefetchPromise) return target.__prefetchPromise;
+    target.__prefetchPromise = (async () => {
+      try {
+        await Promise.all([
+          get().fetchMailboxes(client),
+          get().fetchQuota(client),
+        ]);
+        const { selectedMailbox } = get();
+        if (selectedMailbox) {
+          await get().fetchEmails(client, selectedMailbox);
+        } else {
+          await get().fetchEmails(client);
+        }
+        // Tag counts can finish whenever; don't block the prefetch on them.
+        void get().fetchTagCounts(client);
+      } finally {
+        delete target.__prefetchPromise;
+      }
+    })();
+    return target.__prefetchPromise;
+  },
+
   fetchEmails: async (client, mailboxId) => {
     set({ isLoading: true, error: null }); // Keep previous emails visible during transition
     try {