prefill username in login

src/app/auth/login/device/page.tsx

@@ -7,22 +7,35 @@ import { cache } from "react";
 export const dynamic = "force-dynamic";
 
 type Props = {
-    searchParams: Promise<{ code?: string }>;
+    searchParams: Promise<{ code?: string; user?: string }>;
 };
 
+function deviceRedirectSearchParams(params: {
+    code?: string;
+    user?: string;
+}): string {
+    const search = new URLSearchParams();
+    if (params.code) search.set("code", params.code);
+    if (params.user) search.set("user", params.user);
+    const q = search.toString();
+    return q ? `?${q}` : "";
+}
+
 export default async function DeviceLoginPage({ searchParams }: Props) {
     const user = await verifySession({ forceLogin: true });
 
     const params = await searchParams;
     const code = params.code || "";
+    const defaultUser = params.user;
 
     if (!user) {
-        const redirectDestination = code
-            ? `/auth/login/device?code=${encodeURIComponent(code)}`
-            : "/auth/login/device";
-        redirect(
-            `/auth/login?forceLogin=true&redirect=${encodeURIComponent(redirectDestination)}`
-        );
+        const redirectDestination = `/auth/login/device${deviceRedirectSearchParams({ code, user: params.user })}`;
+        const loginUrl = new URL("/auth/login", "http://x");
+        loginUrl.searchParams.set("forceLogin", "true");
+        loginUrl.searchParams.set("redirect", redirectDestination);
+        if (defaultUser) loginUrl.searchParams.set("user", defaultUser);
+        console.log("loginUrl", loginUrl.pathname + loginUrl.search);
+        redirect(loginUrl.pathname + loginUrl.search);
     }
 
     const userName = user
@@ -37,6 +50,7 @@ export default async function DeviceLoginPage({ searchParams }: Props) {
             userEmail={user?.email || ""}
             userName={userName}
             initialCode={code}
+            userQueryParam={defaultUser}
         />
     );
 }

src/app/auth/login/page.tsx

@@ -72,6 +72,8 @@ export default async function Page(props: {
         searchParams.redirect = redirectUrl;
     }
 
+    const defaultUser = searchParams.user as string | undefined;
+
     // Only use SmartLoginForm if NOT (OSS build OR org-only IdP enabled)
     const useSmartLogin =
         build === "saas" || (build === "enterprise" && env.flags.useOrgOnlyIdp);
@@ -151,6 +153,7 @@ export default async function Page(props: {
                             <SmartLoginForm
                                 redirect={redirectUrl}
                                 forceLogin={forceLogin}
+                                defaultUser={defaultUser}
                             />
                         </CardContent>
                     </Card>
@@ -165,6 +168,7 @@ export default async function Page(props: {
                         (build === "saas" || env.flags.useOrgOnlyIdp)
                     }
                     searchParams={searchParams}
+                    defaultUser={defaultUser}
                 />
             )}
 

src/components/DashboardLoginForm.tsx

@@ -29,6 +29,7 @@ type DashboardLoginFormProps = {
     searchParams?: {
         [key: string]: string | string[] | undefined;
     };
+    defaultUser?: string;
 };
 
 export default function DashboardLoginForm({
@@ -36,7 +37,8 @@ export default function DashboardLoginForm({
     idps,
     forceLogin,
     showOrgLogin,
-    searchParams
+    searchParams,
+    defaultUser
 }: DashboardLoginFormProps) {
     const router = useRouter();
     const { env } = useEnvContext();
@@ -75,6 +77,7 @@ export default function DashboardLoginForm({
                     redirect={redirect}
                     idps={idps}
                     forceLogin={forceLogin}
+                    defaultEmail={defaultUser}
                     onLogin={(redirectUrl) => {
                         if (redirectUrl) {
                             const safe = cleanRedirect(redirectUrl);

src/components/DeviceLoginForm.tsx

@@ -55,12 +55,14 @@ type DeviceLoginFormProps = {
     userEmail: string;
     userName?: string;
     initialCode?: string;
+    userQueryParam?: string;
 };
 
 export default function DeviceLoginForm({
     userEmail,
     userName,
-    initialCode = ""
+    initialCode = "",
+    userQueryParam
 }: DeviceLoginFormProps) {
     const router = useRouter();
     const { env } = useEnvContext();
@@ -219,9 +221,12 @@ export default function DeviceLoginForm({
             const currentSearch =
                 typeof window !== "undefined" ? window.location.search : "";
             const redirectTarget = `/auth/login/device${currentSearch || ""}`;
-            router.push(
-                `/auth/login?forceLogin=true&redirect=${encodeURIComponent(redirectTarget)}`
-            );
+            const loginUrl = new URL("/auth/login", "http://x");
+            loginUrl.searchParams.set("forceLogin", "true");
+            loginUrl.searchParams.set("redirect", redirectTarget);
+            if (userQueryParam)
+                loginUrl.searchParams.set("user", userQueryParam);
+            router.push(loginUrl.pathname + loginUrl.search);
             router.refresh();
         }
     }

src/components/LoginForm.tsx

@@ -54,6 +54,7 @@ type LoginFormProps = {
     idps?: LoginFormIDP[];
     orgId?: string;
     forceLogin?: boolean;
+    defaultEmail?: string;
 };
 
 export default function LoginForm({
@@ -61,7 +62,8 @@ export default function LoginForm({
     onLogin,
     idps,
     orgId,
-    forceLogin
+    forceLogin,
+    defaultEmail
 }: LoginFormProps) {
     const router = useRouter();
 
@@ -116,7 +118,7 @@ export default function LoginForm({
     const form = useForm({
         resolver: zodResolver(formSchema),
         defaultValues: {
-            email: "",
+            email: defaultEmail ?? "",
             password: ""
         }
     });

src/components/SmartLoginForm.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { useState } from "react";
+import { useEffect, useRef, useState } from "react";
 import { useForm } from "react-hook-form";
 import { zodResolver } from "@hookform/resolvers/zod";
 import * as z from "zod";
@@ -42,6 +42,7 @@ const isValidEmail = (str: string): boolean => {
 type SmartLoginFormProps = {
     redirect?: string;
     forceLogin?: boolean;
+    defaultUser?: string;
 };
 
 type ViewState =
@@ -59,7 +60,8 @@ type ViewState =
 
 export default function SmartLoginForm({
     redirect,
-    forceLogin
+    forceLogin,
+    defaultUser
 }: SmartLoginFormProps) {
     const router = useRouter();
     const { lookup, loading, error } = useUserLookup();
@@ -72,10 +74,18 @@ export default function SmartLoginForm({
     const form = useForm<z.infer<typeof identifierSchema>>({
         resolver: zodResolver(identifierSchema),
         defaultValues: {
-            identifier: ""
+            identifier: defaultUser ?? ""
         }
     });
 
+    const hasAutoLookedUp = useRef(false);
+    useEffect(() => {
+        if (defaultUser?.trim() && !hasAutoLookedUp.current) {
+            hasAutoLookedUp.current = true;
+            void handleLookup({ identifier: defaultUser.trim() });
+        }
+    }, [defaultUser]);
+
     const handleLookup = async (values: z.infer<typeof identifierSchema>) => {
         const identifier = values.identifier.trim();
         const isEmail = isValidEmail(identifier);