mctl/cmd/config.go

/*
Copyright © 2025 Jake jake.young.dev@gmail.com
*/
package cmd

import (
	"crypto/rand"
	"fmt"
	"io"
	"os"

	"code.jakeyoungdev.com/jake/mctl/cryptography"
	"github.com/spf13/cobra"
	"github.com/spf13/viper"
	"golang.org/x/term"
)

var (
	cfgserver string
	cfgport   int
)

// configCmd represents the config command
var configCmd = &cobra.Command{
	Use:     "config",
	Example: "mctl config -s x.x.x.x -p 61695",
	Short:   "Create and populate config file",
	Long: `Creates the .mctl file in the user home directory
			populating it with the server address, rcon password, and
			rcon port to be pulled when using Login command`,
	Run: func(cmd *cobra.Command, args []string) {
		//read in password using term to keep it secure/hidden from bash history
		fmt.Printf("Password: ")
		ps, err := term.ReadPassword(int(os.Stdin.Fd()))
		cobra.CheckErr(err)

		//generate and apply random nonce
		nonce := make([]byte, 12)
		_, err = io.ReadFull(rand.Reader, nonce)
		cobra.CheckErr(err)
		viper.Set("nonce", string(nonce))

		//encrypt password
		ciphert, err := cryptography.EncryptPassword(ps)
		cobra.CheckErr(err)

		//update config file with new values
		viper.Set("server", cfgserver)
		viper.Set("password", string(ciphert))
		viper.Set("port", cfgport)
		err = viper.WriteConfig()
		cobra.CheckErr(err)
		fmt.Println()
		fmt.Println("Config file updated!")
	},
}

func init() {
	initConfig()
	configCmd.Flags().StringVarP(&cfgserver, "server", "s", "", "server address")
	err := configCmd.MarkFlagRequired("server")
	cobra.CheckErr(err)
	configCmd.Flags().IntVarP(&cfgport, "port", "p", 0, "server rcon port")
	err = configCmd.MarkFlagRequired("port")
	cobra.CheckErr(err)
	rootCmd.AddCommand(configCmd)
}

// init config sets viper config and checks for config file, creating it if it doesn't exist
func initConfig() {
	home, err := os.UserHomeDir()
	cobra.CheckErr(err)

	viper.AddConfigPath(home)
	viper.SetConfigType("yaml")
	viper.SetConfigName(".mctl")
	viper.AutomaticEnv()
	err = viper.ReadInConfig()
	cobra.CheckErr(err)

	if err := viper.ReadInConfig(); err != nil {
		//file does not exist, create it
		viper.Set("server", cfgserver)
		viper.Set("password", "")
		viper.Set("port", cfgport)
		viper.Set("nonce", "")

		//generate psuedo-random key
		uu := make([]byte, 32)
		_, err := rand.Read(uu)
		cobra.CheckErr(err)

		//create custom command map
		cmdMap := make(map[string]any, 0)

		//write config
		viper.Set("customcmd", cmdMap)
		viper.Set("device", string(uu))
		cobra.CheckErr(viper.SafeWriteConfig())
	}
}