import { NextResponse } from 'next/server';
import type { NextRequest } from 'next/server';
import {
  ATTRIBUTION_COOKIE_NAME,
  buildAttributionSnapshot,
  serializeAttributionCookie,
} from '@/lib/revops';
import { verifySignedUserIdEdge } from '@/lib/session-edge';

const isProduction = process.env.NODE_ENV === 'production';

function attachAttributionCookie(req: NextRequest, response: NextResponse) {
  if (req.cookies.get(ATTRIBUTION_COOKIE_NAME)?.value) {
    return response;
  }

  const path = req.nextUrl.pathname;

  if (path.startsWith('/api/') || path.startsWith('/_next') || path.startsWith('/r/') || path.includes('.')) {
    return response;
  }

  const snapshot = buildAttributionSnapshot({
    utmSource: req.nextUrl.searchParams.get('utm_source'),
    utmMedium: req.nextUrl.searchParams.get('utm_medium'),
    utmCampaign: req.nextUrl.searchParams.get('utm_campaign'),
    utmContent: req.nextUrl.searchParams.get('utm_content'),
    utmTerm: req.nextUrl.searchParams.get('utm_term'),
    referrer: req.headers.get('referer'),
    landingPath: path,
    firstSeenAt: new Date(),
  });

  response.cookies.set(ATTRIBUTION_COOKIE_NAME, serializeAttributionCookie(snapshot), {
    httpOnly: false,
    secure: isProduction,
    sameSite: 'lax',
    path: '/',
    maxAge: 60 * 60 * 24 * 90,
  });

  return response;
}

export async function middleware(req: NextRequest) {
  const path = req.nextUrl.pathname;
  const hostname = req.headers.get('host')?.split(':')[0] || req.nextUrl.hostname;

  if (hostname === 'qrmaster.net') {
    const url = req.nextUrl.clone();
    url.protocol = 'https';
    url.port = '';
    url.hostname = 'www.qrmaster.net';
    return NextResponse.redirect(url, 301);
  }

  // 301 Redirects for /guide -> /learn to avoid duplicate content and consolidate authority
  if (path === '/guide/tracking-analytics') {
    return attachAttributionCookie(req, NextResponse.redirect(new URL('/learn/tracking', req.url), 301));
  }
  if (path === '/guide/bulk-qr-code-generation') {
    return attachAttributionCookie(req, NextResponse.redirect(new URL('/learn/developer', req.url), 301));
  }
  if (path === '/guide/qr-code-best-practices') {
    return attachAttributionCookie(req, NextResponse.redirect(new URL('/learn/basics', req.url), 301));
  }
  if (path === '/create-qr') {
    return attachAttributionCookie(req, NextResponse.redirect(new URL('/dynamic-qr-code-generator', req.url), 301));
  }
  if (path === '/bar-code-generator' || path === '/barcode-generator') {
    return attachAttributionCookie(req, NextResponse.redirect(new URL('/tools/barcode-generator', req.url), 301));
  }

  // Public routes that don't require authentication
  const publicPaths = [
    '/',
    '/pricing',
    '/faq',
    '/blog',
    '/login',
    '/signup',
    '/privacy',
    '/newsletter',
    '/restaurants',
    '/tools',
    '/features',
    // '/guide', // Redirected to /learn/*
    '/de',
    '/qr-code-erstellen',
    '/dynamic-qr-code-generator',
    '/dynamic-barcode-generator',
    '/bulk-qr-code-generator',
    '/qr-code-tracking',
    '/qr-code-analytics',
    '/reprint-calculator',
    '/custom-qr-code-generator',
    '/manage-qr-codes',
    '/coupon',
    '/feedback',
    '/vcard',
    '/display',
    '/contact',
    '/about',
    '/learn',
    '/use-cases',
    '/authors',
    '/press',
    '/testimonials',
    '/qr-code-for-marketing-campaigns',
    '/qr-code-for',
    '/qr-code-print-size-guide',
    '/use-cases/flyer-qr-codes',
    '/use-cases/packaging-qr-codes',
    '/use-cases/real-estate-sign-qr-codes',
    '/use-cases/feedback-qr-codes',
    '/use-cases/payment-qr-codes',
    '/use-cases/coupon-qr-codes',
    '/alternatives',
    '/vs',
  ];

  // Check if path is public
  const isPublicPath = publicPaths.some(p => path === p || path.startsWith(p + '/'));

  // Allow API routes
  if (path.startsWith('/api/')) {
    return attachAttributionCookie(req, NextResponse.next());
  }

  // Allow redirect routes (QR code redirects)
  if (path.startsWith('/r/')) {
    return attachAttributionCookie(req, NextResponse.next());
  }

  // Allow static files
  if (path.includes('.') || path.startsWith('/_next')) {
    return attachAttributionCookie(req, NextResponse.next());
  }

  // Allow public paths
  if (isPublicPath) {
    return attachAttributionCookie(req, NextResponse.next());
  }

  const protectedPaths = [
    '/analytics',
    '/bulk-creation',
    '/create',
    '/dashboard',
    '/integrations',
    '/onboarding',
    '/qr',
    '/settings',
  ];
  const isProtectedPath = protectedPaths.some(p => path === p || path.startsWith(p + '/'));

  if (!isProtectedPath) {
    return attachAttributionCookie(req, NextResponse.next());
  }

  // For protected routes, require a validly signed userId cookie
  const userId = await verifySignedUserIdEdge(req.cookies.get('userId')?.value);

  if (!userId) {
    // Not authenticated - redirect to signup
    const signupUrl = new URL('/signup', req.url);
    const redirectTarget = `${path}${req.nextUrl.search}`;
    signupUrl.searchParams.set('redirect', redirectTarget);
    return attachAttributionCookie(req, NextResponse.redirect(signupUrl));
  }

  // Authenticated - allow access
  return attachAttributionCookie(req, NextResponse.next());
}

export const config = {
  matcher: [
    /*
     * Match all request paths except for the ones starting with:
     * - _next/static (static files)
     * - _next/image (image optimization files)
     * - favicon.ico (favicon file)
     * - public folder
     */
    '/((?!_next/static|_next/image|favicon.ico|logo.svg|og-image.png).*)',
  ],
};