middleware.ts

import { NextResponse } from 'next/server';
import type { NextRequest } from 'next/server';

export function middleware(request: NextRequest) {
  const token = request.cookies.get('auth-token')?.value;
  const pathname = request.nextUrl.pathname;
  
  // Public routes that don't require authentication
  const publicRoutes = ['/login', '/register', '/api/auth/login', '/api/auth/register'];
  const isPublicRoute = publicRoutes.some(route => pathname.startsWith(route));
  
  // Static assets and Next.js internals
  if (
    pathname.startsWith('/_next') ||
    pathname.startsWith('/static') ||
    pathname.includes('.') ||
    pathname === '/favicon.ico'
  ) {
    return NextResponse.next();
  }
  
  // Redirect to login if no token and not on public route
  if (!token && !isPublicRoute) {
    return NextResponse.redirect(new URL('/login', request.url));
  }
  
  // Redirect to dashboard if token exists and trying to access login/register
  if (token && (pathname === '/login' || pathname === '/register')) {
    return NextResponse.redirect(new URL('/dashboard', request.url));
  }
  
  // Redirect root to dashboard if authenticated, otherwise to login
  if (pathname === '/') {
    if (token) {
      return NextResponse.redirect(new URL('/dashboard', request.url));
    } else {
      return NextResponse.redirect(new URL('/login', request.url));
    }
  }
  
  return NextResponse.next();
}

export const config = {
  matcher: ['/((?!_next/static|_next/image|favicon.ico).*)'],
};