import { NextResponse } from "next/server";
import type { NextRequest } from "next/server";

// Paths that don't require authentication
const PUBLIC_PATHS = ["/login", "/signup", "/api/auth"];

function isPublicPath(pathname: string): boolean {
  return PUBLIC_PATHS.some((p) => pathname === p || pathname.startsWith(p + "/"));
}

export function middleware(request: NextRequest) {
  const { pathname } = request.nextUrl;

  // Allow public paths (login, auth callbacks)
  if (isPublicPath(pathname)) {
    return NextResponse.next();
  }

  // Production-only blocking without explicit config
  if (process.env.NODE_ENV === "production") {
    const explicitlyEnabled = process.env.ADMIN_ALLOW_PRODUCTION === "true";
    const hasAuth = Boolean(
      process.env.BETTER_AUTH_SECRET && process.env.BETTER_AUTH_URL,
    );

    if (!explicitlyEnabled || !hasAuth) {
      return new NextResponse(
        "MicProtocol Admin is not exposed in production without explicit configuration. " +
          "Set ADMIN_ALLOW_PRODUCTION=true and configure real authentication to enable it.",
        { status: 503 },
      );
    }
  }

  // Auth gating: check for Better Auth session cookie or dev-mode header
  const sessionCookie = request.cookies.get("better-auth.session");
  const devUserId = request.headers.get("x-user-id");

  if (!sessionCookie && !devUserId) {
    const loginUrl = new URL("/login", request.url);
    loginUrl.searchParams.set("callbackUrl", pathname);
    return NextResponse.redirect(loginUrl);
  }

  return NextResponse.next();
}

export const config = {
  matcher: ["/((?!_next|.*\\..*).*)"],
};