package main

import "fmt"
import "io"
import "log"
import "os"
import "bufio"
import "strings"

func longest(r io.Reader) string {
	lw := ""
	s := bufio.NewScanner(r)
	s.Split(bufio.ScanWords)
	for s.Scan() {
		word := s.Text()
		word = strings.ToLower(word)
		word = strings.Replace(word, ".", "", -1)
		word = strings.Replace(word, ",", "", -1)
		word = strings.Replace(word, "\"", "", -1)
		for _, word := range strings.Split(word, "—") {
			if len(word) > len(lw) {
				if !strings.HasPrefix(word, "http://") {
					lw = word
				}
			}
		}
	}
	return lw
}

func openFile(path *string) *os.File {
	f, err := os.Open(os.Args[1])
	if err != nil {
		log.Fatalln(err)
	}
	return f
}
func main() {
	if len(os.Args) <= 1 {
		log.Fatalln("Missing file")
	}
	f := openFile(&os.Args[1])

	fmt.Println(longest(f))
}