package args

import (
	"flag"
	"os"
	"strings"
)

type Arguments struct {
	DatabasePath string
	TemplatePath string
	StaticPath   string

	Migrate   bool
	Scheduler bool

	Port   int
	Server bool

	// Dns runs the authoritative DNS server for the LAN. DnsZone is the suffix
	// it owns (e.g. penguins.lan); queries outside it are forwarded to
	// DnsResolvers (empty = no forwarding, since the LAN has no outside
	// internet). ServerIP (env SERVER_IP) answers the zone apex so the website
	// itself resolves; empty leaves the apex unanswered.
	Dns          bool
	DnsPort      int
	DnsResolvers []string
	DnsZone      string
	ServerIP     string

	// DevMAC (env DEV_MAC) forces every client's MAC, for testing auth from
	// loopback where the browser never appears in the ARP table.
	DevMAC string

	// Minecraft RCON, for the server status panel. Empty address disables it.
	RconAddress  string
	RconPassword string

	// LanSubnet (env LAN_SUBNET, e.g. 192.168.8.0/24) is swept to populate the
	// ARP table for idle devices. Empty disables the sweep.
	LanSubnet string
}

func GetArgs() (*Arguments, error) {
	databasePath := flag.String("database-path", "./db/penguins.db", "Path to the SQLite database")
	templatePath := flag.String("template-path", "./templates", "Path to the template directory")
	staticPath := flag.String("static-path", "./static", "Path to the static directory")

	migrate := flag.Bool("migrate", false, "Run the migrations on startup")
	scheduler := flag.Bool("scheduler", false, "Run the background scheduler (ARP refresh, session cleanup)")

	port := flag.Int("port", 8080, "Port to listen on")
	server := flag.Bool("server", false, "Run the HTTP server")

	dns := flag.Bool("dns", false, "Run the authoritative DNS server")
	dnsPort := flag.Int("dns-port", 8053, "Port for the DNS server to listen on")
	dnsZone := flag.String("dns-zone", "penguins.lan", "DNS zone this server is authoritative for")
	dnsResolvers := flag.String("dns-resolvers", "", "Comma-separated upstream resolvers for non-zone queries (empty disables forwarding)")

	flag.Parse()

	resolvers := []string{}
	for _, r := range strings.Split(*dnsResolvers, ",") {
		if r = strings.TrimSpace(r); r != "" {
			resolvers = append(resolvers, r)
		}
	}

	return &Arguments{
		DatabasePath: *databasePath,
		TemplatePath: *templatePath,
		StaticPath:   *staticPath,
		Migrate:      *migrate,
		Scheduler:    *scheduler,
		Port:         *port,
		Server:       *server,
		Dns:          *dns,
		DnsPort:      *dnsPort,
		DnsResolvers: resolvers,
		DnsZone:      *dnsZone,
		ServerIP:     os.Getenv("SERVER_IP"),
		DevMAC:       os.Getenv("DEV_MAC"),
		RconAddress:  os.Getenv("RCON_ADDRESS"),
		RconPassword: os.Getenv("RCON_PASSWORD"),
		LanSubnet:    os.Getenv("LAN_SUBNET"),
	}, nil
}