import type { NextConfig } from "next";

const apiUrl = process.env.API_URL ?? "http://127.0.0.1:4000";

/**
 * Security headers for the web origin. CSP itself is issued PER REQUEST with a
 * nonce by src/middleware.ts (Next attaches the nonce to its bootstrap scripts);
 * everything static lives here. In production behind HTTPS, HSTS pins the host.
 */
const securityHeaders = [
  { key: "X-Content-Type-Options", value: "nosniff" },
  { key: "X-Frame-Options", value: "DENY" },
  { key: "Referrer-Policy", value: "strict-origin-when-cross-origin" },
  { key: "Permissions-Policy", value: "camera=(), microphone=(), geolocation=()" },
  ...(process.env.NODE_ENV === "production"
    ? [{ key: "Strict-Transport-Security", value: "max-age=15552000; includeSubDomains" }]
    : []),
];

const nextConfig: NextConfig = {
  poweredByHeader: false,
  async rewrites() {
    // Same-origin proxy to the API — keeps cookies/CSRF simple (no CORS)
    return [{ source: "/api/:path*", destination: `${apiUrl}/api/:path*` }];
  },
  async headers() {
    return [{ source: "/:path*", headers: securityHeaders }];
  },
};

export default nextConfig;