import { clerkMiddleware, createRouteMatcher } from "@clerk/nextjs/server";
import { NextResponse } from "next/server";
import { timingSafeStringEqual } from "@/lib/timing-safe-compare";

const isPublicRoute = createRouteMatcher([
  "/",
  "/sign-up(.*)",
  "/log-in(.*)",
  "/forgot-password(.*)",
  "/reset-password(.*)",
  "/verify-email(.*)",
  "/health-card/(.*)",
  "/api/gdpr-export/(.*)",
  "/opengraph-image",
  "/impressum",
  "/datenschutz",
  "/nutzungsbedingungen",
  "/join(.*)",
  "/api/webhooks/(.*)",
  "/api/auth/(.*)",
  "/api/cron/(.*)",
  "/api/csp-report",
  // tRPC handles its own auth per-procedure (protectedProcedure vs.
  // publicProcedure) and returns a proper JSON UNAUTHORIZED error — letting
  // Clerk's page-level auth.protect() intercept it first produced a 307 HTML
  // redirect to the sign-in page instead, which a JSON API client can't
  // parse, and incorrectly blocked publicProcedure calls (e.g.
  // explore.listPets) for logged-out visitors entirely.
  "/api/trpc/(.*)",
]);

function getSupabaseHostname(): string {
  const url = process.env.NEXT_PUBLIC_SUPABASE_URL;
  if (url) {
    try {
      return new URL(url).hostname;
    } catch {
      /* fall through */
    }
  }
  return "*.supabase.co";
}

function getGlitchtipHostname(): string {
  const dsn = process.env.NEXT_PUBLIC_SENTRY_DSN;
  if (dsn) {
    try {
      return new URL(dsn).hostname;
    } catch {
      /* fall through */
    }
  }
  return "glitchtip.pawfeed.org";
}

export default clerkMiddleware(
  async (auth, request) => {
    const { pathname } = request.nextUrl;

    // Invite gate: block /sign-up unless the visitor has a valid invite cookie.
    // Set INVITE_REQUIRED=false in env to disable for the live/post-beta launch.
    if (pathname.startsWith("/sign-up")) {
      const inviteRequired = process.env.INVITE_REQUIRED !== "false";
      if (inviteRequired && !request.cookies.has("pf_invite")) {
        return NextResponse.redirect(new URL("/join", request.url));
      }
    }

    // Admin panel: validate secret path segment before anything else.
    // Returns 404 (not 403) — the panel's existence must not be revealed.
    if (pathname.startsWith("/p/")) {
      const segments = pathname.split("/");
      const providedSecret = segments[2] ?? "";
      const adminSecret = process.env.ADMIN_SECRET ?? "";

      if (!adminSecret || !timingSafeStringEqual(providedSecret, adminSecret)) {
        return new NextResponse(null, { status: 404 });
      }
    }

    if (!isPublicRoute(request)) {
      await auth.protect();
    }
  },
  {
    // Report-Only for now — an earlier enforced attempt blanked the whole
    // app because ClerkProvider crashes uncaught when a required resource
    // gets blocked mid-init. Clerk's own contentSecurityPolicy option (not
    // the hand-rolled next.config.ts draft this replaces) already ships the
    // 'unsafe-inline'/https: script-src Next.js needs to hydrate, which is
    // what the hand-rolled version was missing. Move to enforced only after
    // a clean report-only period — see /api/csp-report for the violations.
    contentSecurityPolicy: {
      reportOnly: true,
      reportTo: "/api/csp-report",
      directives: {
        "img-src": [`https://${getSupabaseHostname()}`, "https://image.mux.com", "blob:"],
        "connect-src": [
          `https://${getSupabaseHostname()}`,
          `https://${getGlitchtipHostname()}`,
          "https://stream.mux.com",
          "https://image.mux.com",
          "https://litix.io",
          "https://storage.googleapis.com",
        ],
        "media-src": ["self", "blob:", "https://stream.mux.com", "https://*.edgemv.mux.com"],
        "font-src": ["self", "data:"],
        "frame-ancestors": ["none"],
        "object-src": ["none"],
        "base-uri": ["self"],
        "report-uri": ["/api/csp-report"],
      },
    },
  }
);

export const config = {
  matcher: [
    "/((?!_next|[^?]*\\.(?:html?|css|js(?!on)|jpe?g|webp|png|gif|svg|ttf|woff2?|ico|csv|docx?|xlsx?|zip|webmanifest)).*)",
    "/(api|trpc)(.*)",
    "/__clerk/(.*)",
  ],
};