feat(ui): shared header — Sign in/Sign out and New Chat on every page; hide the Sources nav link from anonymous users

2026-08-24 12:32:45 -04:00
parent fd7f02ce68
commit 2afc77ee56
14 changed files with 904 additions and 59 deletions
@@ -0,0 +1,96 @@
+/* Brain of Reese — shared header module (phase 19).
+ *
+ * Owner report 2026-08-23: clicking "Sources" made New Chat and Sign in
+ * vanish — the user expects ONE consistent bar on every page. This module
+ * is the single owner of the shared header controls:
+ *
+ *   • the Sign in / Sign out auth pair (phase 16, exactly one visible —
+ *     decided by /api/whoami at load);
+ *   • the "Sources" nav link (#nav-sources) — phase 19 UX revision
+ *     (owner permission 2026-08-23): hidden for anonymous on every page
+ *     that has a nav (chat, sources, login), revealed for admin. The
+ *     link SHIPS hidden in the HTML (anonymous-safe default — the
+ *     phase-16 "absent, not hidden" spirit), so no anonymous user ever
+ *     sees it for a frame;
+ *   • the sign-out click binding (POST /api/logout → reload) — moved
+ *     here from app.js so there is exactly one implementation;
+ *   • clearChatStorage() — the phase-14 conversation key, for the
+ *     New Chat buttons on the NON-CHAT pages (sources / document
+ *     viewer): a new chat means going to the chat, fresh.
+ *
+ * Every page loads this module (type="module", before its page script)
+ * and its page script calls initSharedHeader() once at boot. init…
+ * toggles ONLY the controls that exist on the page — a missing element
+ * is a no-op, which is how the login page reuses the module without
+ * gaining chat controls (no #new-chat-btn / #sign-in-link /
+ * #sign-out-btn in its markup → none appear).
+ *
+ * whoami is fetched at most ONCE per page load: the promise is cached in
+ * the module-level `adminPromise`, so app.js's tuning gate, the sources
+ * page's catalog gate, and the header toggling all share one request.
+ * Anonymous-safe: any network failure resolves to false (the anonymous
+ * UI), mirroring the per-page catch the pages used before phase 19.
+ *
+ * A10/A11 untouched: no API change, no CDN, no state beyond the cached
+ * promise; the soft gate page and the A10 API split are unchanged —
+ * this is UI visibility only.
+ */
+
+let adminPromise = null;
+
+/* The SINGLE /api/whoami call site for the whole frontend. First call
+   stores the promise in `adminPromise`; every later call — on this page
+   — returns the same promise, i.e. exactly one request per page load.
+   Anonymous-safe: non-2xx or a network failure resolves to false. */
+export function fetchIsAdmin() {
+  if (!adminPromise) {
+    adminPromise = fetch("/api/whoami")
+      .then(async (r) => (r.ok ? (await r.json()).authenticated === true : false))
+      .catch(() => false);
+  }
+  return adminPromise;
+}
+
+/* Toggle the shared header controls, only the ones present on this page
+   (querySelector, null-safe — missing → no-op). Returns the admin flag
+   so callers can reuse it instead of awaiting fetchIsAdmin() again (the
+   cached promise makes both awaits the same single request). */
+export async function initSharedHeader() {
+  const admin = await fetchIsAdmin();
+  const signIn = document.querySelector("#sign-in-link");
+  if (signIn) signIn.hidden = admin;
+  const signOut = document.querySelector("#sign-out-btn");
+  if (signOut) signOut.hidden = !admin;
+  const navSources = document.querySelector("#nav-sources");
+  if (navSources) navSources.hidden = !admin;
+  return admin;
+}
+
+/* Remove the phase-14 conversation key — same key + fail-silence
+   contract as app.js's clearStoredConversation: private mode or a
+   storage error is swallowed, the navigation still happens. */
+export function clearChatStorage() {
+  try {
+    localStorage.removeItem("bor.chat.v1");
+  } catch {
+    /* nothing was stored */
+  }
+}
+
+/* Sign-out binding (phase 16 behavior, now module-owned): runs at module
+   import, so every page that loads header.js gets it exactly once.
+   Disable during the call, POST /api/logout (the result is ignored —
+   the reload resets the UI either way), then reload so the header
+   re-resolves to the anonymous state (Sign in back, Sources gone). */
+const signOutBtn = document.querySelector("#sign-out-btn");
+if (signOutBtn) {
+  signOutBtn.addEventListener("click", async () => {
+    signOutBtn.disabled = true;
+    try {
+      await fetch("/api/logout", { method: "POST" });
+    } catch {
+      /* the reload resets the UI either way */
+    }
+    window.location.reload();
+  });
+}