From 9c22252e0be318eb0b58c35c54bb5f91fabb0419 Mon Sep 17 00:00:00 2001
From: Dominik Stahl <dominik@samdj.de>
Date: Mon, 12 May 2025 21:22:56 +0200
Subject: [PATCH] refactor: dynamically generated login page

---
 src/app/login/page.tsx             | 14 +++++----
 src/auth.ts                        | 47 +++++++++++++++++++++++++-----
 src/components/labeled-input.tsx   |  9 +++---
 src/components/user/login-form.tsx | 22 +++++++++++++-
 4 files changed, 75 insertions(+), 17 deletions(-)

diff --git a/src/app/login/page.tsx b/src/app/login/page.tsx
index 714e996..1786e82 100644
--- a/src/app/login/page.tsx
+++ b/src/app/login/page.tsx
@@ -1,4 +1,4 @@
-import { auth } from '@/auth';
+import { auth, providerMap } from '@/auth';
 import SSOLogin from '@/components/user/sso-login-button';
 import LoginForm from '@/components/user/login-form';
 import { redirect } from 'next/navigation';
@@ -35,11 +35,15 @@ export default async function LoginPage() {
             <CardContent className='gap-6 flex flex-col'>
               <LoginForm />
 
-              <hr />
+              {providerMap.length > 0 && <hr />}
 
-              {process.env.AUTH_AUTHENTIK_ISSUER && (
-                <SSOLogin provider='authentik' providerDisplayName='SSO' />
-              )}
+              {providerMap.map((provider) => (
+                <SSOLogin
+                  key={provider.id}
+                  provider={provider.id}
+                  providerDisplayName={provider.name}
+                />
+              ))}
             </CardContent>
           </Card>
         </div>
diff --git a/src/auth.ts b/src/auth.ts
index b3ed869..09a5065 100644
--- a/src/auth.ts
+++ b/src/auth.ts
@@ -1,16 +1,49 @@
 import NextAuth from 'next-auth';
+
+import type { Provider } from 'next-auth/providers';
+import Credentials from 'next-auth/providers/credentials';
+
 import Authentik from 'next-auth/providers/authentik';
 
+const providers: Provider[] = [
+  !process.env.DISABLE_PASSWORD_LOGIN &&
+    Credentials({
+      credentials: { password: { label: 'Password', type: 'password' } },
+      authorize(c) {
+        if (c.password !== 'password') return null;
+        return {
+          id: 'test',
+          name: 'Test User',
+          email: 'test@example.com',
+        };
+      },
+    }),
+  process.env.AUTH_AUTHENTIK_ID && Authentik,
+].filter(Boolean) as Provider[];
+
+export const providerMap = providers
+  .map((provider) => {
+    if (typeof provider === 'function') {
+      const providerData = provider();
+      return { id: providerData.id, name: providerData.name };
+    } else {
+      return { id: provider.id, name: provider.name };
+    }
+  })
+  .filter((provider) => provider.id !== 'credentials');
+
 export const { handlers, signIn, signOut, auth } = NextAuth({
-  providers: [process.env.AUTH_AUTHENTIK_ISSUER ? Authentik : null].filter(
-    (x) => x !== null,
-  ),
-  callbacks: {
-    authorized: async ({ auth }) => {
-      return !!auth?.user;
-    },
+  providers,
+  session: {
+    strategy: 'jwt',
   },
   pages: {
     signIn: '/login',
+    signOut: '/logout',
+  },
+  callbacks: {
+    authorized({ auth }) {
+      return !!auth?.user;
+    },
   },
 });
diff --git a/src/components/labeled-input.tsx b/src/components/labeled-input.tsx
index 7b4768a..7a416d4 100644
--- a/src/components/labeled-input.tsx
+++ b/src/components/labeled-input.tsx
@@ -6,23 +6,24 @@ export default function LabeledInput({
   label,
   placeholder,
   value,
+  name,
 }: {
   type: 'text' | 'email' | 'password';
   label: string;
   placeholder?: string;
   value?: string;
+  name?: string;
 }) {
-  const elementId = Math.random().toString(36).substring(2, 15);
-
   return (
     <div className='flex flex-col gap-1'>
-      <Label htmlFor={elementId}>{label}</Label>
+      <Label htmlFor={name}>{label}</Label>
 
       <Input
         type={type}
         placeholder={placeholder}
         defaultValue={value}
-        id={elementId}
+        id={name}
+        name={name}
       />
     </div>
   );
diff --git a/src/components/user/login-form.tsx b/src/components/user/login-form.tsx
index 20438e8..2869930 100644
--- a/src/components/user/login-form.tsx
+++ b/src/components/user/login-form.tsx
@@ -1,18 +1,38 @@
+import { signIn } from '@/auth';
 import LabeledInput from '@/components/labeled-input';
 import { Button } from '@/components/ui/button';
+import { AuthError } from 'next-auth';
+import { redirect } from 'next/navigation';
+
+const SIGNIN_ERROR_URL = '/error';
 
 export default function LoginForm() {
   return (
-    <form className='flex flex-col gap-5 w-full'>
+    <form
+      className='flex flex-col gap-5 w-full'
+      action={async (formData) => {
+        'use server';
+        try {
+          await signIn('credentials', formData);
+        } catch (error) {
+          if (error instanceof AuthError) {
+            return redirect(`${SIGNIN_ERROR_URL}?error=${error.type}`);
+          }
+          throw error;
+        }
+      }}
+    >
       <LabeledInput
         type='email'
         label='E-Mail'
         placeholder='Enter your E-Mail'
+        name='email'
       />
       <LabeledInput
         type='password'
         label='Password'
         placeholder='Enter your Password'
+        name='password'
       />
       <Button
         className='hover:bg-blue-600 hover:text-white'