Dynamic Branding, Instance name and description on log in sign up page.

src/app/api/auth/check-handle/route.ts

@@ -0,0 +1,30 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { db, users } from '@/db';
+import { eq } from 'drizzle-orm';
+
+export async function GET(req: NextRequest) {
+    try {
+        const { searchParams } = new URL(req.url);
+        const handle = searchParams.get('handle')?.toLowerCase().trim();
+
+        if (!handle || handle.length < 3) {
+            return NextResponse.json({ available: false, error: 'Handle too short' });
+        }
+
+        if (!/^[a-zA-Z0-9_]+$/.test(handle)) {
+            return NextResponse.json({ available: false, error: 'Invalid characters' });
+        }
+
+        const existingUser = await db.query.users.findFirst({
+            where: eq(users.handle, handle),
+        });
+
+        return NextResponse.json({
+            available: !existingUser,
+            handle
+        });
+    } catch (error) {
+        console.error('Check handle error:', error);
+        return NextResponse.json({ error: 'Failed to check handle' }, { status: 500 });
+    }
+}