import (
    "fmt"
    "github.com/urfave/cli"
    "log"
    "net"
    "os"
)


func main() {

    app := cli.NewApp()
    app.Name = "Website Lookup CLI"
    app.Usage = "Let's you query IPs, CNAMEs, MX records and Name Servers!"
    app.Version = "1.0.0"
    app.Author = "Adeshina H. H."

    // We'll be using the same flag for all our commands
    // so we'll define it up here
    myFlags := []cli.Flag{
        cli.StringFlag{
            Name:  "host",
            Value: "tutorialedge.net",
        },
    }

    // we create our commands
    app.Commands = []cli.Command{
        {
            Name:  "ns",
            Usage: "Looks Up the NameServers for a Particular Host",
            Flags: myFlags,
            // the action, or code that will be executed when
            // we execute our `ns` command
            Action: func(c *cli.Context) error {
                // a simple lookup function
                ns, err := net.LookupNS(c.String("url"))
                if err != nil {
                    return err
                }
                // we log the results to our console
                // using a trusty fmt.Println statement
                for i := 0; i < len(ns); i++ {
                    fmt.Println(ns[i].Host)
                }
                return nil
            },
        },


    }


    // start our application
    err := app.Run(os.Args)
    if err != nil {
        log.Fatal(err)
    }
}