find twitter unfollowers

unfollowers.go

package main

import (
	"bytes"
	"fmt"
	"io/ioutil"
	"log"
	"strings"
)

func main() {
	dat, err := ioutil.ReadFile("untitled")
	if err != nil {
		log.Fatal("unable to readFile")
	}
	parts := bytes.Split(dat, []byte("ProfileCard-userFields"))
	log.Printf("parts: %d", len(parts))
	var unfollowers []string
	parts = parts[1:]
	for _, p := range parts {
		if follows(p) {
			continue
		}
		u := username(p)
		if u != "" {
			unfollowers = append(unfollowers, u)
		}
	}
	var urls []string
	for _, val := range unfollowers {
		urls = append(urls, fmt.Sprintf("https://twitter.com/%s", val))
	}
	all := strings.Join(urls, "\n")
	err = ioutil.WriteFile("out.txt", []byte(all), 0644)
	if err != nil {
		log.Fatal(err)
	}
}

func follows(dat []byte) bool {
	i := bytes.Index(dat, []byte("ProfileCard-bio"))
	if i < 0 {
		log.Fatalf("missing ProfileCard-bio: %s", dat)
	}
	return bytes.Contains(dat[:i], []byte("follows you"))
}
func username(dat []byte) string {
	i := bytes.Index(dat, []byte("ProfileCard-screenname"))
	j := bytes.Index(dat, []byte("screennameLink"))
	if i < 0 || j < i {
		return ""
	}
	s := string(dat[i:j])
	i = strings.Index(s, "href=")
	j = strings.Index(s, "class=\"ProfileCard")
	if i < 0 || j < i {
		return ""
	}
	return s[i+7 : j-2]
}