/** @type {import('next').NextConfig} */
const nextConfig = {
  reactStrictMode: true,
  swcMinify: true,
  // Configure cache busting with build ID
  generateBuildId: async () => {
    return process.env.BUILD_ID || `build-${Date.now()}`
  },
  images: {
    domains: [],
    formats: ['image/avif', 'image/webp'],
    deviceSizes: [640, 750, 828, 1080, 1200, 1920, 2048, 3840],
    imageSizes: [16, 32, 48, 64, 96, 128, 256, 384],
  },
  experimental: {
    optimizePackageImports: ['lucide-react', '@react-three/fiber', '@react-three/drei'],
  },
  webpack: (config, { isServer }) => {
    if (!isServer) {
      // Optimize bundle splitting
      config.optimization.splitChunks = {
        chunks: 'all',
        cacheGroups: {
          default: false,
          vendors: false,
          framework: {
            name: 'framework',
            chunks: 'all',
            test: /(?<!node_modules.*)[\\/]node_modules[\\/](react|react-dom|scheduler|prop-types|use-subscription)[\\/]/,
            priority: 40,
            enforce: true,
          },
          lib: {
            test: /[\\/]node_modules[\\/]/,
            name(module) {
              const packageName = module.context.match(/[\\/]node_modules[\\/](.*?)([\\/]|$)/)?.[1]
              return `npm.${packageName?.replace('@', '')}`
            },
            priority: 30,
            minChunks: 1,
            reuseExistingChunk: true,
          },
          commons: {
            name: 'commons',
            minChunks: 2,
            priority: 20,
          },
          shared: {
            name() {
              return 'shared'
            },
            minChunks: 2,
            priority: 10,
            reuseExistingChunk: true,
          },
        },
      }
    }
    return config
  },
  async headers() {
    const isDev = process.env.NODE_ENV === 'development'
    
    return [
      {
        source: '/:path*',
        headers: [
          {
            key: 'Content-Type',
            value: 'text/html; charset=utf-8',
          },
          {
            key: 'X-Content-Type-Options',
            value: 'nosniff',
          },
          {
            key: 'X-DNS-Prefetch-Control',
            value: 'on',
          },
          {
            key: 'Strict-Transport-Security',
            value: 'max-age=63072000; includeSubDomains; preload',
          },
          {
            key: 'X-Frame-Options',
            value: 'DENY',
          },
          // X-XSS-Protection removed - deprecated and not needed with CSP
          {
            key: 'Referrer-Policy',
            value: 'strict-origin-when-cross-origin',
          },
          {
            key: 'Permissions-Policy',
            value: 'camera=(), microphone=(), geolocation=()',
          },
          // CSP is required for security
          // In development, Next.js requires 'unsafe-eval' for hot reloading
          // In production, we use stricter CSP without eval
          {
            key: 'Content-Security-Policy',
            value: [
              "default-src 'self'",
              isDev
                ? "script-src 'self' 'unsafe-eval' 'unsafe-inline'"
                : "script-src 'self' 'unsafe-inline'",
              "style-src 'self' 'unsafe-inline'",
              "img-src 'self' data: https:",
              "font-src 'self' data:",
              "connect-src 'self' https: ws: wss:",
            ].join('; '),
          },
        ],
      },
      // Content-Type headers for static assets (Next.js handles these automatically, but we ensure charset)
      {
        source: '/_next/static/:path*',
        headers: [
          {
            key: 'Cache-Control',
            value: 'public, max-age=31536000, immutable',
          },
        ],
      },
      {
        source: '/_next/static/css/:path*.css',
        headers: [
          {
            key: 'Content-Type',
            value: 'text/css; charset=utf-8',
          },
        ],
      },
      {
        source: '/_next/static/chunks/:path*.js',
        headers: [
          {
            key: 'Content-Type',
            value: 'text/javascript; charset=utf-8',
          },
        ],
      },
    ]
  },
}

module.exports = nextConfig