import type { NextConfig } from "next";
import { defaultLocale, locales } from "./src/i18n/routes";

const PUBLIC_TO_INTERNAL: Record<string, string> = {
  "/": "/de",
  "/ueber-mich": "/de/about",
  "/projekte": "/de/projects",
  "/kontakt": "/de/contact",
  "/impressum": "/de/legal",
  "/datenschutz": "/de/privacy",
  "/en": "/en",
  "/en/about": "/en/about",
  "/en/projects": "/en/projects",
  "/en/contact": "/en/contact",
  "/en/legal": "/en/legal",
  "/en/privacy": "/en/privacy",
};

function projectItemRewrite(srcPrefix: string, destLocale: "de" | "en") {
  return {
    source: `${srcPrefix}/:slug`,
    destination: `/${destLocale}/projects/:slug`,
  };
}

// Content-Security-Policy. Bewusst moderat, weil Next.js inline-styles und
// inline-scripts für Hydration + RSC braucht. 'unsafe-inline' ist hier
// akzeptabel, weil wir kein User-Generated-Content haben und alle Skripte
// aus dem eigenen Build kommen — XSS via externe Quelle ist trotzdem geblockt.
// TODO: Migration zu Nonces sobald der RSC-Stream nonces unterstützt.
const CSP = [
  "default-src 'self'",
  "script-src 'self' 'unsafe-inline' 'unsafe-eval'",
  "style-src 'self' 'unsafe-inline'",
  "img-src 'self' data: https:",
  "font-src 'self' data:",
  "connect-src 'self'",
  "frame-ancestors 'none'",
  "base-uri 'self'",
  "form-action 'self'",
  "object-src 'none'",
].join("; ");

const config: NextConfig = {
  serverExternalPackages: ["better-sqlite3"],
  images: { unoptimized: true },
  output: "standalone",
  // View-Transitions-API wird via CSS ::view-transition-* in theme.css
  // genutzt (siehe dort). Next.js 16 hat keinen experimental.viewTransition-
  // Switch — die CSS-Regeln reichen aus, der Browser aktiviert die
  // Transition automatisch beim ersten Cross-Document-Navigation mit dem
  // Meta-View-Transition-Tag.
  async rewrites() {
    return [
      ...Object.entries(PUBLIC_TO_INTERNAL).map(([from, to]) => ({
        source: from,
        destination: to,
      })),
      projectItemRewrite("/projekte", "de"),
      projectItemRewrite("/en/projects", "en"),
    ];
  },
  async headers() {
    return [
      {
        source: "/:path*",
        headers: [
          { key: "Content-Security-Policy", value: CSP },
          { key: "X-DNS-Prefetch-Control", value: "off" },
          { key: "Strict-Transport-Security", value: "max-age=63072000; includeSubDomains; preload" },
          { key: "X-Content-Type-Options", value: "nosniff" },
          { key: "Referrer-Policy", value: "strict-origin-when-cross-origin" },
          { key: "Permissions-Policy", value: "camera=(), microphone=(), geolocation=(), payment=()" },
        ],
      },
    ];
  },
};

export default config;