package config

import (
	"flag"
	"fmt"
	"net"
)

type Config struct {
	HTTPHost         string
	HTTPPort         int
	UDPHost          string
	UDPPort          int
	MaintenanceIP    string
	MaintenanceCIDR  string
	AdminPassword    string
	ServerVersion    string
	DeviceIDFallback string
}

func Load(args []string) Config {
	cfg := Config{
		HTTPHost:         "0.0.0.0",
		HTTPPort:         48888,
		UDPHost:          "0.0.0.0",
		UDPPort:          50000,
		MaintenanceIP:    "169.254.100.2",
		MaintenanceCIDR:  "169.254.100.2/16",
		AdminPassword:    "Dt123$",
		ServerVersion:    "0.1.0",
		DeviceIDFallback: "networktool-device",
	}

	fs := flag.NewFlagSet("networktool-server", flag.ContinueOnError)
	fs.StringVar(&cfg.MaintenanceIP, "ip", cfg.MaintenanceIP, "maintenance IPv4 address")
	fs.IntVar(&cfg.HTTPPort, "port", cfg.HTTPPort, "HTTP listen port")
	fs.StringVar(&cfg.AdminPassword, "password", cfg.AdminPassword, "admin password")
	_ = fs.Parse(args)

	if parsed := net.ParseIP(cfg.MaintenanceIP); parsed == nil || parsed.To4() == nil {
		panic(fmt.Sprintf("invalid maintenance ip: %s", cfg.MaintenanceIP))
	}

	cfg.MaintenanceCIDR = fmt.Sprintf("%s/16", cfg.MaintenanceIP)

	return cfg
}