middleware.ts

import { NextRequest, NextResponse } from "next/server";
import { isbot } from "isbot";

import { analytics } from "@/util/analytics";
import { rateLimiter } from "./lib/rate-limiter";

export default async function middleware(req: NextRequest) {
  const ip = req.headers.get("x-forwarded-for");
  const agent = req.headers.get("user-agent");

  if (req.nextUrl.pathname.startsWith("/api/v1")) {
    const { success, limit, reset, remaining } = await rateLimiter.limit(
      `ratelimit_${ip}`
    );
    if (!success) {
      return new Response(
        JSON.stringify({
          error: true,
          message: "rate limit exceeded, 5 request per second allowed",
        }),
        {
          status: 429,
          headers: {
            "X-RateLimit-Limit": limit.toString(),
            "X-RateLimit-Remaining": remaining.toString(),
            "X-RateLimit-Reset": reset.toString(),
          },
        }
      );
    }
  }

  if (req.nextUrl.pathname === "/" && !isbot(agent) && req.method === "GET") {
    await analytics.track(process.env.ADMIN_ID!, "tail-track", {
      country: req.geo?.country,
      ref: req.nextUrl.searchParams.get("ref") ?? "direct",
    });
  }

  return NextResponse.next();
}

export const config = {
  matcher: [
    {
      source: "/((?!_next/static|_next/image|favicon.ico).*)",
      missing: [
        { type: "header", key: "next-router-prefetch" },
        { type: "header", key: "purpose", value: "prefetch" },
      ],
    },
  ],
};