// Command httpstub is a trivial local HTTP server used only by
// scripts/run-local-e2e.sh, standing in for two kinds of real internet
// resources so the offline end-to-end harness needs no real internet
// access:
//   - "/" always returns 200 OK — stands in for the real outbound egress
//     targets (hub.docker.com, github.com, packages.ubuntu.com).
//   - "/ip" echoes the caller's remote address as plain text — stands in
//     for the external IP-echo service the validator-agent's self-check
//     queries in production (see internal/agentcore.detectPublicIP and
//     config.SelfCheckCfg.IPEchoURLs). Because httpstub runs locally, this
//     only produces a meaningful self-check signal in the harness because
//     the "floating IP" under test is itself the loopback address the
//     caller genuinely connects from — it is not a stand-in for OpenStack's
//     SNAT behavior.
package main

import (
	"flag"
	"fmt"
	"log"
	"net"
	"net/http"
)

func main() {
	addr := flag.String("addr", ":9090", "address to listen on")
	flag.Parse()

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte("stub ok\n"))
	})
	http.HandleFunc("/ip", func(w http.ResponseWriter, r *http.Request) {
		host, _, err := net.SplitHostPort(r.RemoteAddr)
		if err != nil {
			host = r.RemoteAddr
		}
		w.Header().Set("Content-Type", "text/plain")
		fmt.Fprintln(w, host)
	})
	log.Printf("httpstub listening on %s", *addr)
	log.Fatal(http.ListenAndServe(*addr, nil))
}