import type { NextConfig } from "next";
import withPWAInit from "next-pwa";

// Conditionally load bundle analyzer only when ANALYZE=true (dev dependency)
const withBundleAnalyzer = process.env.ANALYZE === "true"
  // eslint-disable-next-line @typescript-eslint/no-require-imports
  ? require("@next/bundle-analyzer")({ enabled: true })
  : (config: NextConfig) => config;

/**
 * Security headers config for Next.js
 * Inline to avoid path alias resolution issues at runtime
 */
function getNextConfigSecurityHeaders(): Array<{
  source: string;
  headers: Array<{ key: string; value: string }>;
}> {
  const securityHeaders = [
    { key: 'X-DNS-Prefetch-Control', value: 'on' },
    { key: 'X-Content-Type-Options', value: 'nosniff' },
    { key: 'X-Frame-Options', value: 'DENY' },
    { key: 'X-XSS-Protection', value: '1; mode=block' },
    { key: 'Referrer-Policy', value: 'strict-origin-when-cross-origin' },
    { key: 'Permissions-Policy', value: 'camera=(), microphone=(), geolocation=(), interest-cohort=()' },
  ];

  return [
    {
      source: '/:path*',
      headers: securityHeaders,
    },
  ];
}

const withPWA = withPWAInit({
  dest: "public",
  disable: process.env.NODE_ENV === "development",
  register: true,
  skipWaiting: true,
  // Fallback for offline pages
  fallbacks: {
    document: "/offline",
  },
  // Runtime caching strategies
  runtimeCaching: [
    // Google Fonts - Cache First (rarely changes)
    {
      urlPattern: /^https:\/\/fonts\.(?:googleapis|gstatic)\.com\/.*/i,
      handler: "CacheFirst",
      options: {
        cacheName: "google-fonts",
        expiration: {
          maxEntries: 4,
          maxAgeSeconds: 365 * 24 * 60 * 60, // 1 year
        },
      },
    },
    // Static font assets
    {
      urlPattern: /\.(?:eot|otf|ttc|ttf|woff|woff2|font\.css)$/i,
      handler: "StaleWhileRevalidate",
      options: {
        cacheName: "static-font-assets",
        expiration: {
          maxEntries: 4,
          maxAgeSeconds: 7 * 24 * 60 * 60, // 1 week
        },
      },
    },
    // Images - Stale While Revalidate for quick loading
    {
      urlPattern: /\.(?:jpg|jpeg|gif|png|svg|ico|webp|avif)$/i,
      handler: "StaleWhileRevalidate",
      options: {
        cacheName: "static-image-assets",
        expiration: {
          maxEntries: 64,
          maxAgeSeconds: 30 * 24 * 60 * 60, // 30 days
        },
      },
    },
    // JavaScript files
    {
      urlPattern: /\/_next\/static.+\.js$/i,
      handler: "CacheFirst",
      options: {
        cacheName: "next-static-js-assets",
        expiration: {
          maxEntries: 64,
          maxAgeSeconds: 24 * 60 * 60, // 24 hours
        },
      },
    },
    // CSS files
    {
      urlPattern: /\.(?:css|less)$/i,
      handler: "StaleWhileRevalidate",
      options: {
        cacheName: "static-style-assets",
        expiration: {
          maxEntries: 32,
          maxAgeSeconds: 24 * 60 * 60, // 24 hours
        },
      },
    },
    // API routes - Network First for fresh data
    {
      urlPattern: /\/api\/.*/i,
      handler: "NetworkFirst",
      options: {
        cacheName: "api-cache",
        networkTimeoutSeconds: 10,
        expiration: {
          maxEntries: 32,
          maxAgeSeconds: 60 * 60, // 1 hour
        },
        cacheableResponse: {
          statuses: [0, 200],
        },
      },
    },
    // Next.js data fetching
    {
      urlPattern: /\/_next\/data\/.+\/.+\.json$/i,
      handler: "StaleWhileRevalidate",
      options: {
        cacheName: "next-data",
        expiration: {
          maxEntries: 32,
          maxAgeSeconds: 24 * 60 * 60, // 24 hours
        },
      },
    },
    // All other requests - Network First
    {
      urlPattern: /.*/i,
      handler: "NetworkFirst",
      options: {
        cacheName: "others",
        networkTimeoutSeconds: 10,
        expiration: {
          maxEntries: 32,
          maxAgeSeconds: 24 * 60 * 60, // 24 hours
        },
      },
    },
  ],
});

const nextConfig: NextConfig = {
  // Enable gzip compression
  compress: true,

  // Empty turbopack config to silence the warning about webpack config
  // (next-pwa plugin adds webpack config, but Next.js 16+ defaults to Turbopack)
  turbopack: {},

  // Experimental features for bundle optimization
  experimental: {
    // Optimize imports for better tree-shaking
    optimizePackageImports: [
      'lucide-react',
      '@radix-ui/react-icons',
      'recharts',
      'framer-motion',
      'date-fns',
    ],
  },

  // Exclude server-only packages from bundling (prevents Turbopack from trying to bundle test files)
  serverExternalPackages: [
    'pino',
    'pino-pretty',
    'thread-stream',
    // OpenTelemetry packages with Node.js-only dependencies
    '@opentelemetry/auto-instrumentations-node',
    '@opentelemetry/instrumentation-net',
    '@opentelemetry/instrumentation-dns',
    '@opentelemetry/instrumentation-fs',
    '@opentelemetry/sdk-node',
  ],

  images: {
    // Configure remote patterns for external image sources
    remotePatterns: [
      {
        protocol: 'https',
        hostname: 'res.cloudinary.com',
        pathname: '/**',
      },
      {
        protocol: 'https',
        hostname: '*.cloudinary.com',
        pathname: '/**',
      },
    ],
    // Note: Custom loader is available at @/lib/images/cloudinary-loader
    // Use it via the `loader` prop on individual Image components that need Cloudinary optimization
    // Do NOT set global loader: 'custom' as it breaks local images
    // Optimize images with these device sizes
    deviceSizes: [640, 750, 828, 1080, 1200, 1920, 2048, 3840],
    // Sizes for responsive images
    imageSizes: [16, 32, 48, 64, 96, 128, 256, 384],
    // Image formats to use - include AVIF for better compression
    formats: ["image/avif", "image/webp"],
    // Cache optimized images for 1 year
    minimumCacheTTL: 60 * 60 * 24 * 365,
  },

  // Remove console logs in production (except errors)
  compiler: {
    removeConsole: process.env.NODE_ENV === "production" ? {
      exclude: ["error", "warn"],
    } : false,
  },

  // Redirects for URL changes (SEO-friendly permanent redirects)
  async redirects() {
    return [
      {
        source: '/shop-with-sidebar',
        destination: '/shop',
        permanent: true, // 308 redirect for SEO
      },
      {
        source: '/shop-with-sidebar/:path*',
        destination: '/shop/:path*',
        permanent: true,
      },
    ];
  },

  // HTTP headers for caching static assets
  async headers() {
    return [
      {
        // Cache static images for 1 year (immutable)
        source: "/images/:path*",
        headers: [
          {
            key: "Cache-Control",
            value: "public, max-age=31536000, immutable",
          },
        ],
      },
      {
        // Cache Cloudinary proxy images for 1 year
        source: "/api/images/:path*",
        headers: [
          {
            key: "Cache-Control",
            value: "public, max-age=31536000, s-maxage=31536000, stale-while-revalidate=86400",
          },
        ],
      },
      {
        // Cache Next.js static files for 1 year (immutable)
        source: "/_next/static/:path*",
        headers: [
          {
            key: "Cache-Control",
            value: "public, max-age=31536000, immutable",
          },
        ],
      },
      {
        // Cache fonts for 1 year
        source: "/fonts/:path*",
        headers: [
          {
            key: "Cache-Control",
            value: "public, max-age=31536000, immutable",
          },
        ],
      },
      {
        // Service worker should not be cached
        source: "/sw.js",
        headers: [
          {
            key: "Cache-Control",
            value: "no-cache, no-store, must-revalidate",
          },
        ],
      },
      // Security headers for all routes
      ...getNextConfigSecurityHeaders(),
    ];
  },
};

export default withBundleAnalyzer(withPWA(nextConfig));