package main

import (
	"log"
	"net/http"
)

func helloHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		return
	}

	w.Header().Set("Content-Type", "text/plain")
	w.WriteHeader(http.StatusOK)
	w.Write([]byte("Hello world"))
}

func main() {
	http.HandleFunc("/", helloHandler)

	port := ":8080"
	log.Printf("Server starting on port %s", port)
	log.Fatal(http.ListenAndServe(port, nil))
}