middleware.ts

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

export const config = {
  matcher: [
    "/((?!api/|_next/|_static/|[\\w-]+\\.\\w+).*)",
  ],
};

export async function middleware(req: NextRequest) {
  const url = req.nextUrl;
  let hostname = req.headers.get("host") || '';

  // Remove port if it exists
  hostname = hostname.split(':')[0];

  // Define allowed domains (including main domain and localhost)
  const allowedDomains = ["tudominio.ar", "www.tudominio.ar", "localhost"];

  // Check if the current hostname is in the list of allowed domains
  const isMainDomain = allowedDomains.includes(hostname);

  // Extract subdomain if not a main domain
  const subdomain = isMainDomain ? null : hostname.split('.')[0];

  console.log('Middleware: Hostname:', hostname);
  console.log('Middleware: Subdomain:', subdomain);

  // If it's a main domain, allow the request to proceed
  if (isMainDomain) {
    console.log('Middleware: Main domain detected, passing through');
    return NextResponse.next();
  }

  // Handle subdomain logic
  if (subdomain) {
    try {
      // Use fetch to verify if the subdomain exists
      const response = await fetch(`${url.origin}/api/tenant?subdomain=${subdomain}`);
      
      if (response.ok) {
        console.log('Middleware: Valid subdomain detected, rewriting URL');
        // Rewrite the URL to a dynamic route based on the subdomain
        return NextResponse.rewrite(new URL(`/${subdomain}${url.pathname}`, req.url));
      }
    } catch (error) {
      console.error('Middleware: Error fetching tenant:', error);
    }
  }

  console.log('Middleware: Invalid subdomain or domain, returning 404');
  // If none of the above conditions are met, return a 404 response
  return new NextResponse(null, { status: 404 });
}