// Homework 35, problem 3: A counter that remembers.
//
// Start from your visit counter. Save the count to visits.json on every visit,
// and load it when the server starts, so that it carries on after a restart. A
// missing file means a count of 0. A broken file stops the server at start, with
// a clear message. If saving fails, the visitor gets status 500, and the count
// stays as it was. The file is created in the folder you run the program from.
//
// Run with: go run exercises/35/homework/03-saved-counter.go

package main

import (
	"fmt"
	"net/http"
)

const visitsFile = "visits.json"

// TODO: add the mutex, the count, loadVisits and nextVisit here.

func handleHome(w http.ResponseWriter, r *http.Request) {
	// TODO: write your code here, in place of this placeholder line:
	fmt.Fprintln(w, "TODO: replace this line, and save to", visitsFile)
}

func main() {
	// TODO: load the count here.

	http.HandleFunc("GET /{$}", handleHome)

	fmt.Println("Server running at http://localhost:8080")
	fmt.Println("Press Ctrl+C to stop it.")

	err := http.ListenAndServe("localhost:8080", nil)
	if err != nil {
		fmt.Println("Server stopped:", err)
	}
}