package sources

import (
	"bufio"
	"iplistget/common"
	"net"
	"os"
	"strings"
)

func init() {
	common.RegisterSource(File{FileName: "iplistget.txt"})
}

type File struct {
	FileName string
}

func (s File) Get(filename string) ([]net.IPNet, error) {
	if filename != "" {
		s.FileName = filename
	}

	file, err := os.Open(s.FileName)
	if err != nil {
		return nil, err
	}
	defer file.Close()

	ipmap := map[string]bool{}

	// TODO Provide custom split function for scanner to be universal
	scanner := bufio.NewScanner(file)
	for scanner.Scan() {
		ip := scanner.Text()
		if !strings.Contains(ip, "/") {
			ip += "/32"
		}
		ipmap[ip] = true
	}

	if err := scanner.Err(); err != nil {
		return nil, err
	}

	iplist := make([]net.IPNet, 0, len(ipmap))
	for key, _ := range ipmap {
		if _, ipnet, err := net.ParseCIDR(key); err == nil {
			iplist = append(iplist, *ipnet)
		}
	}

	return iplist, nil
}