package main

import (
	"flag"
	"log"
	"math/rand"
	"net/http"
	"os"
	"os/signal"
	"time"
)

func main() {
	// Set up flags
	log.Println("Setting up components")
	registerHTTPFlags()
	registerSessionFlags()
	registerCredentialsFlags()
	registerSeedFlags()
	registerAccessFlags()
	flag.Parse()

	// Read challenges from file
	log.Println("Reading seed file")
	readChallengesError := getChallengesFromSeedFile()
	if readChallengesError != nil {
		log.Fatalln(readChallengesError.Error())
	}

	// Seed the random number generator
	log.Println("Seed random number generator")
	rand.Seed(time.Now().UTC().UnixNano())

	// Start our VPN container and network
	log.Printf("Starting VPN container ('%s')", vpnContainerName)
	startVPNError := startVPN()
	if startVPNError != nil {
		log.Fatalln(startVPNError.Error())
	}

	// Set up HTTP server
	log.Printf("Running HTTP server on port %d", *port)
	httpServer := setupHTTPServer()

	// React to system signals
	signalChannel := make(chan os.Signal, 1)
	signal.Notify(signalChannel)
	go cleanup(signalChannel, httpServer)

	// Start our HTTP server
	log.Fatalln(httpServer.ListenAndServe())
}

func cleanup(signalChannel chan os.Signal, server http.Server) {
	// Block until we receive a signal
	<- signalChannel
	log.Println("Requested shutdown")

	// Stop everything
	log.Println("Stopping HTTP server")
	server.Close()
	log.Println("Stopping VPN container")
	stopVPN()
	log.Println("Stopping challenge containers")
	stopAllChallengeContainers()
	log.Println("Deleting Docker networks")
	deleteNetwork(getVPNNetworkName())
	deleteNetwork(getChallengeNetworkName())
	os.Exit(0)
}