v0.8.0 — Update-available detection (version chip + changelog)

Footer becomes a changelog chip and shows an 'Update available' badge when a
newer APP_VERSION exists upstream. Detection reads src/lib/version.ts from the
Gitea default branch (dms model) and compares — self-contained, no OTM control
plane. Adds src/lib/update-check.ts and GET /api/version (also a running-version
probe for the upcoming one-click rebuild).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app/api/version/route.ts

@@ -0,0 +1,19 @@
+import { NextResponse } from "next/server";
+import { requireAuth } from "@/lib/auth";
+import { getUpdateStatus } from "@/lib/update-check";
+
+export const dynamic = "force-dynamic";
+
+// Running-version probe + upstream update check. Used by the footer chip, and
+// (later) polled by the self-update UI to detect when the rebuilt instance is
+// back online on the new version.
+export async function GET() {
+  try {
+    await requireAuth();
+  } catch {
+    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+  }
+  return NextResponse.json(await getUpdateStatus(), {
+    headers: { "Cache-Control": "no-store" },
+  });
+}

src/components/layout/footer.tsx

@@ -1,12 +1,83 @@
-import Link from "next/link";
+"use client";
+
+import { useEffect, useState } from "react";
+import {
+  Dialog,
+  DialogContent,
+  DialogHeader,
+  DialogTitle,
+} from "@/components/ui/dialog";
 import { APP_VERSION } from "@/lib/version";
+import { CHANGELOG } from "@/lib/changelog";
+import type { UpdateStatus } from "@/lib/update-check";
 
 export function Footer() {
+  const [open, setOpen] = useState(false);
+  const [status, setStatus] = useState<UpdateStatus | null>(null);
+
+  useEffect(() => {
+    let cancelled = false;
+    fetch("/api/version")
+      .then((r) => (r.ok ? r.json() : null))
+      .then((d) => {
+        if (!cancelled) setStatus(d);
+      })
+      .catch(() => {});
+    return () => {
+      cancelled = true;
+    };
+  }, []);
+
+  const updateAvailable = status?.updateAvailable && status.latest;
+
   return (
-    <footer className="h-8 border-t flex items-center justify-end px-4 md:px-6 shrink-0">
-      <span className="text-[11px] text-muted-foreground/60">
-        Moon Base v{APP_VERSION}
+    <>
+      <footer className="h-8 border-t flex items-center justify-end gap-2 px-4 md:px-6 shrink-0">
+        {updateAvailable && (
+          <span
+            className="text-[11px] font-medium rounded-full px-2 py-0.5 bg-amber-100 text-amber-800"
+            title={`Version ${status!.latest} is available`}
+          >
+            Update available → v{status!.latest}
           </span>
+        )}
+        <button
+          type="button"
+          onClick={() => setOpen(true)}
+          className="text-[11px] text-muted-foreground/60 hover:text-foreground transition-colors tabular-nums"
+          title="Show changelog"
+        >
+          Moon Base v{APP_VERSION}
+        </button>
       </footer>
+
+      <Dialog open={open} onOpenChange={setOpen}>
+        <DialogContent className="max-h-[80vh] overflow-y-auto">
+          <DialogHeader>
+            <DialogTitle>Changelog</DialogTitle>
+          </DialogHeader>
+          {updateAvailable && (
+            <p className="text-sm rounded-md px-3 py-2 bg-amber-50 text-amber-800">
+              A newer version (v{status!.latest}) is available. You're on v{APP_VERSION}.
+            </p>
+          )}
+          <div className="space-y-5">
+            {CHANGELOG.map((entry) => (
+              <div key={entry.version} className="space-y-1.5">
+                <div className="flex items-baseline gap-2">
+                  <span className="font-semibold text-sm tabular-nums">v{entry.version}</span>
+                  <span className="text-xs text-muted-foreground">{entry.date}</span>
+                </div>
+                <ul className="text-sm space-y-1 list-disc pl-5 marker:text-muted-foreground">
+                  {entry.changes.map((c, i) => (
+                    <li key={i}>{c}</li>
+                  ))}
+                </ul>
+              </div>
+            ))}
+          </div>
+        </DialogContent>
+      </Dialog>
+    </>
   );
 }

src/lib/changelog.ts

@@ -8,6 +8,13 @@ export type ChangelogEntry = {
 };
 
 export const CHANGELOG: ChangelogEntry[] = [
+  {
+    version: "0.8.0",
+    date: "2026-06-15",
+    changes: [
+      "The app now tells you when a newer version is available — a little \"Update available\" badge appears in the bottom bar, and the version number opens the full changelog. (One-click updating is coming next.)",
+    ],
+  },
   {
     version: "0.7.0",
     date: "2026-06-15",

src/lib/update-check.ts

@@ -0,0 +1,60 @@
+import { APP_VERSION } from "./version";
+
+// Detects whether a newer version has been pushed upstream by reading
+// src/lib/version.ts from the Gitea repo's default branch and comparing its
+// APP_VERSION to the running one. Self-contained — no OTM control plane needed.
+// Reuses the same GITEA_* env as the suggestions module.
+const GITEA_URL = process.env.GITEA_URL;
+const GITEA_TOKEN = process.env.GITEA_TOKEN;
+const GITEA_REPO = process.env.GITEA_REPO;
+const GITEA_BRANCH = process.env.GITEA_BRANCH || "master";
+
+export type UpdateStatus = {
+  version: string;
+  latest: string | null;
+  updateAvailable: boolean;
+};
+
+/** Read APP_VERSION from src/lib/version.ts on the upstream branch. null on any failure. */
+export async function fetchUpstreamVersion(): Promise<string | null> {
+  if (!GITEA_URL || !GITEA_TOKEN || !GITEA_REPO) return null;
+  try {
+    const url = `${GITEA_URL}/api/v1/repos/${GITEA_REPO}/contents/src/lib/version.ts?ref=${GITEA_BRANCH}`;
+    const res = await fetch(url, {
+      headers: { Authorization: `token ${GITEA_TOKEN}` },
+      cache: "no-store",
+    });
+    if (!res.ok) return null;
+    const json = await res.json();
+    if (!json?.content) return null;
+    const decoded = Buffer.from(
+      json.content,
+      json.encoding === "base64" ? "base64" : "utf8"
+    ).toString("utf8");
+    const m = decoded.match(/APP_VERSION\s*=\s*["']([^"']+)["']/);
+    return m ? m[1] : null;
+  } catch {
+    return null;
+  }
+}
+
+/** Numeric dotted compare. -1 if a<b, 0 if equal, 1 if a>b. */
+export function compareVersions(a: string, b: string): number {
+  const pa = a.split(".").map((n) => parseInt(n, 10) || 0);
+  const pb = b.split(".").map((n) => parseInt(n, 10) || 0);
+  const len = Math.max(pa.length, pb.length);
+  for (let i = 0; i < len; i++) {
+    const d = (pa[i] || 0) - (pb[i] || 0);
+    if (d !== 0) return d > 0 ? 1 : -1;
+  }
+  return 0;
+}
+
+export async function getUpdateStatus(): Promise<UpdateStatus> {
+  const latest = await fetchUpstreamVersion();
+  return {
+    version: APP_VERSION,
+    latest,
+    updateAvailable: latest != null && compareVersions(latest, APP_VERSION) > 0,
+  };
+}

src/lib/version.ts

@@ -1,2 +1,2 @@
 // Bump on every user-visible release. Changelog entries live in `src/lib/changelog.ts`.
-export const APP_VERSION = "0.7.0";
+export const APP_VERSION = "0.8.0";