package main

import("fmt"
      "strings"
      "net"
      "net/smtp"
      "log"
    )

  var(
    hostlist = make([]string,0)
    result = ""
    err  error
  )

func main(){
    var toemail,fromemail string = "bharatsewani1993@gmail.com","bharatsewani@gmail.com"
    //var toemail string = "bharatsewani1993@gmail.com"
    //  var getdetails bool

    //get the domain name from email recipient
    email_arr := strings.Split(toemail,"@")
    domain := email_arr[1]

    //get mx record of domain
    mxhosts,err := net.LookupMX(domain)
    if err != nil{
      panic(err)
    }

    //if mx record not found get dns record of domain
    if len(mxhosts) < 1 {
        dnshosts,err := net.LookupNS(domain)
        if err != nil{
          panic(err)
        }
        if len(dnshosts) > 0{
          for i := 0; i < len(dnshosts); i++ {
            hostlist = append(hostlist,dnshosts[i].Host)
          }
        }
      } else {
        //found mxhosts
        for i := 0; i < len(mxhosts); i++ {
          hostlist = append(hostlist,mxhosts[i].Host)
        }
      }

      //check if host list is not empty
      if len(hostlist) > 0{
        ip := hostlist[0]
        //connect to smtp server
        c, err := smtp.Dial(ip+":25")
        if err != nil {
          log.Fatal(err)
        }

        hello := c.Hello(ip)
        from := c.Mail(fromemail)
        to := c.Rcpt(toemail)
        quit := c.Quit()

        fmt.Println("Hello ==> ",hello)
        fmt.Println("From ==> ",from)
        fmt.Println("to ==> ",to)
        fmt.Println("Quit ==>", quit)
        // Send the email body.

      } else {
        fmt.Println("invalid")
        fmt.Println("No suitable mx record found!")
      }

}