import type { NextConfig } from "next";

const isDev = process.env.NODE_ENV !== "production";

// Content-Security-Policy — in der Entwicklung etwas lockerer (HMR/Eval),
// in Produktion ohne 'unsafe-eval'. 'unsafe-inline' für Styles, da Tailwind/
// Next inline-Styles nutzen.
const csp = [
  "default-src 'self'",
  `script-src 'self' 'unsafe-inline'${isDev ? " 'unsafe-eval'" : ""}`,
  "style-src 'self' 'unsafe-inline'",
  "img-src 'self' data: blob:",
  // blob: nötig für die lokale Sprachnachricht-Vorschau vor dem Senden.
  "media-src 'self' blob:",
  "font-src 'self' data:",
  "connect-src 'self'" + (isDev ? " ws: http://localhost:*" : ""),
  "object-src 'none'",
  "base-uri 'self'",
  "form-action 'self'",
  "frame-ancestors 'none'",
  "upgrade-insecure-requests",
].join("; ");

const securityHeaders = [
  { key: "Content-Security-Policy", value: csp },
  { key: "X-Frame-Options", value: "DENY" },
  { key: "X-Content-Type-Options", value: "nosniff" },
  { key: "Referrer-Policy", value: "strict-origin-when-cross-origin" },
  {
    // Mikrofon für Sprachnachrichten erlauben (self); Kamera für spätere Calls.
    key: "Permissions-Policy",
    value: "camera=(self), microphone=(self), geolocation=(), interest-cohort=()",
  },
  {
    key: "Strict-Transport-Security",
    value: "max-age=63072000; includeSubDomains; preload",
  },
];

const nextConfig: NextConfig = {
  poweredByHeader: false,
  reactStrictMode: true,
  async headers() {
    return [{ source: "/:path*", headers: securityHeaders }];
  },
};

export default nextConfig;