feat: integrate Google OAuth authentication provider and add login UI button

apps/backend/.env.example

@@ -12,3 +12,7 @@ SMTP_PORT=587
 SMTP_USER=user@example.com
 SMTP_PASS=your-smtp-password
 SMTP_FROM=Playzer <no-reply@example.com>
+
+# Google OAuth
+GOOGLE_CLIENT_ID=your-google-client-id
+GOOGLE_CLIENT_SECRET=your-google-client-secret

apps/backend/src/lib/auth.ts

@@ -17,7 +17,21 @@ export const auth = betterAuth({
   emailAndPassword: {
     enabled: true,
   },
-  trustedOrigins: [process.env.APP_BASE_URL ?? 'http://localhost:5173'],
+  socialProviders: {
+    google: {
+      clientId: process.env.GOOGLE_CLIENT_ID!,
+      clientSecret: process.env.GOOGLE_CLIENT_SECRET!,
+    },
+  },
+  advanced: {
+    generateUsername: async (data) => {
+      return `user_${Date.now()}`;
+    },
+  },
+  trustedOrigins: [
+    process.env.APP_BASE_URL ?? 'http://localhost:5173',
+    process.env.BETTER_AUTH_URL ?? 'http://localhost:3000',
+  ],
   plugins: [openAPI()],
 });
 

apps/frontend/src/features/login/login-page.tsx

@@ -1,6 +1,7 @@
 import { Button } from '@/components/ui/button';
 import { Field, FieldError, FieldLabel } from '@/components/ui/field';
 import { Input } from '@/components/ui/input';
+import { authClient } from '@/lib/api-client';
 import { useAuth } from '@/lib/auth';
 import { zodResolver } from '@hookform/resolvers/zod';
 import { Link, useNavigate } from '@tanstack/react-router';
@@ -48,6 +49,21 @@ export function LoginPage({ redirectTo = '/' }: LoginPageProps) {
     }
   };
 
+  const handleGoogleSignIn = async () => {
+    setSubmitError(null);
+
+    try {
+      await authClient.signIn.social({
+        provider: 'google',
+        callbackURL: redirectTo.startsWith('http')
+          ? redirectTo
+          : `http://localhost:5173${redirectTo}`,
+      });
+    } catch {
+      setSubmitError('No pudimos iniciar sesión con Google.');
+    }
+  };
+
   return (
     <main className="flex min-h-screen w-full items-center justify-center px-6">
       <section className="w-full max-w-sm rounded-xl border bg-card p-6 text-card-foreground shadow-sm">
@@ -56,6 +72,37 @@ export function LoginPage({ redirectTo = '/' }: LoginPageProps) {
           Ingresá con tu cuenta para acceder a Home.
         </p>
 
+        <Button type="button" variant="outline" className="w-full" onClick={handleGoogleSignIn}>
+          <svg className="mr-2 h-4 w-4" viewBox="0 0 24 24" aria-hidden="true">
+            <path
+              fill="currentColor"
+              d="M22.56 12.25c0-.78-.07-1.53-.2-2.25H12v4.26h5.92c-.26 1.37-1.04 2.53-2.21 3.31v2.77h3.57c2.08-1.92 3.28-4.74 3.28-8.09z"
+            />
+            <path
+              fill="currentColor"
+              d="M12 23c2.97 0 5.46-.98 7.28-2.66l-3.57-2.77c-.98.66-2.23 1.06-3.71 1.06-2.86 0-5.29-1.93-6.16-4.53H2.18v2.84C3.99 20.53 7.7 23 12 23z"
+            />
+            <path
+              fill="currentColor"
+              d="M5.84 14.09c-.22-.66-.35-1.36-.35-2.09s.13-1.43.35-2.09V7.07H2.18C1.43 8.55 1 10.22 1 12s.43 3.45 1.18 4.93l2.85-2.22.81-.62z"
+            />
+            <path
+              fill="currentColor"
+              d="M12 5.38c1.62 0 3.06.56 4.21 1.64l3.15-3.15C17.45 2.09 14.97 1 12 1 7.7 1 3.99 3.47 2.18 7.07l3.66 2.84c.87-2.6 3.3-4.53 6.16-4.53z"
+            />
+          </svg>
+          Continuar con Google
+        </Button>
+
+        <div className="relative my-4">
+          <div className="absolute inset-0 flex items-center">
+            <span className="w-full border-t" />
+          </div>
+          <div className="relative flex justify-center text-xs uppercase">
+            <span className="bg-card px-2 text-muted-foreground">O</span>
+          </div>
+        </div>
+
         <form className="space-y-3" onSubmit={handleSubmit(onSubmit)}>
           <Field data-invalid={Boolean(errors.email)}>
             <FieldLabel htmlFor="email">Email</FieldLabel>