1 files changed, 46 insertions, 0 deletions
diff --git a/jb-ui/src/pages/MagicAMTLink.tsx b/jb-ui/src/pages/MagicAMTLink.tsx
new file mode 100644
index 0000000..fdd7437
--- /dev/null
+++ b/jb-ui/src/pages/MagicAMTLink.tsx
@@ -0,0 +1,46 @@
+import { useEffect, useRef, useState } from "react";
+
+type ExchangeState = "working" | "failed" | "missing";
+
+const MagicLink = function () {
+  const started = useRef(false);
+  const [state, setState] = useState<ExchangeState>("working");
+
+  useEffect(() => {
+    // React Strict Mode runs effects twice in development. Never redeem twice.
+    if (started.current) return;
+    started.current = true;
+
+    const params = new URLSearchParams(window.location.search);
+    const token = params.get("token");
+    if (!token) {
+      setState("missing");
+      return;
+    }
+
+    // Keep the credential out of browser history and subsequent Referer headers.
+    window.history.replaceState({}, "", window.location.pathname);
+
+    void fetch("/auth/link-amt/exchange/", {
+      method: "POST",
+      credentials: "include",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({ token: token }),
+    })
+      .then((response) => {
+        if (!response.ok) throw new Error("Magic-link exchange failed");
+        window.location.replace("/");
+      })
+      .catch(() => setState("failed"));
+  }, []);
+
+  if (state === "missing") {
+    return <p>This login link is missing its token.</p>;
+  }
+  if (state === "failed") {
+    return <p>This login link is invalid or has expired.</p>;
+  }
+  return <p>Signing you in…</p>;
+};
+
+export default MagicLink;