package main
  
  import (
  	"bufio"
  	"fmt"
  	"io"
  	"log"
  	"os"
  	"os/exec"
  )
  
  func main() {
  	var host string
  	var out io.Writer
  
  	if l := len(os.Args); l == 1 {
  		host = "172.30.0.1"
  		out = os.Stdout
  	} else if l == 2 {
  		host = os.Args[1]
  		out = os.Stdout
  	} else {
  		f, err := os.OpenFile(os.Args[2], os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0666)
  		if err != nil {
  			log.Fatal(err)
  		}
  		defer f.Close()
  
  		host = os.Args[1]
  		out = f
  	}
  
  	test("hw-wifi", host, out)
  }
  
  func test(code, host string, out io.Writer) {
  	c := exec.Command("iperf", "-c", host, "-i", "1", "-t", "10")
  	stdout, err := c.StdoutPipe()
  
  	err = c.Start()
  	if err != nil {
  		log.Fatal(err)
  	}
  
  	state := 0
  
  	s := bufio.NewScanner(stdout)
  	for s.Scan() {
  		fmt.Fprintf(out, "{\"code\": \"%v\", \"state\": %v, \"data\": \"%v\", \"timeout\": 10}
  ", code, state, s.Text())
  		if state < 90 {
  			state += 10
  		}
  	}
  
  	fmt.Fprintf(out, "{\"code\": \"%v\", \"state\": 100, \"data\": \"\", \"timeout\": 10}
  ", code)
  }