package main

import (
    "fmt"
    "os"
    "time"

    "github.com/anacrolix/dht"
    "github.com/anacrolix/torrent"
)

func waitForInfo(clientTorrent *torrent.Torrent, seconds time.Duration) (deleted bool) {
    timeout := make(chan bool, 1) //creating a timeout channel for our gotinfo
    go func() {
        time.Sleep(seconds * time.Second)
        timeout <- true
    }()
    select {
    case <-clientTorrent.GotInfo(): //attempting to retrieve info for torrent
        clientTorrent.DownloadAll()
        return false
    case <-timeout: // getting info for torrent has timed out so purging the torrent
        clientTorrent.Drop()
        return true
    }

}

func main() {

    config := torrent.Config{DataDir: "downloads",
        DHTConfig: dht.ServerConfig{StartingNodes: dht.GlobalBootstrapAddrs},
    }

    tclient, err := torrent.NewClient(&config) //pulling out the torrent specific config to use
    if err != nil {
        fmt.Println("Error with creating client", err)
    }

    ubuntuTorrent, err := tclient.AddMagnet("magnet:?xt=urn:btih:9f9165d9a281a9b8e782cd5176bbcc8256fd1871&dn=Ubuntu+16.04.1+LTS+Desktop+64-bit&tr=udp%3A%2F%2Ftracker.leechers-paradise.org%3A6969&tr=udp%3A%2F%2Fzer0day.ch%3A1337&tr=udp%3A%2F%2Fopen.demonii.com%3A1337&tr=udp%3A%2F%2Ftracker.coppersurfer.tk%3A6969&tr=udp%3A%2F%2Fexodus.desync.com%3A6969")
    if err != nil {
        fmt.Println("Error adding Torrent", err)
    }
    timedOut := waitForInfo(ubuntuTorrent, 30)
    if timedOut {
        fmt.Println("Timed out awaiting info...")
        os.Exit(3)
    }
    ubuntuTorrent.DownloadAll()
    fmt.Println("downloading all.. now sleeping 60 seconds..")
    time.Sleep(60 * time.Second)
    fmt.Println("now forcing max connections to zero.")
    fmt.Println("current amount downloaded", ubuntuTorrent.Stats().BytesReadUsefulData)
    fmt.Println("Number of open peers", ubuntuTorrent.Stats().ActivePeers)
    ubuntuTorrent.SetMaxEstablishedConns(0)
    fmt.Println("now waiting 10 seconds")

    time.Sleep(10 * time.Second)
    oldMax := ubuntuTorrent.SetMaxEstablishedConns(80)
    fmt.Println("Reseting peers", oldMax)
    fmt.Println("now waiting 10 seconds")
    time.Sleep(10 * time.Second)
    ubuntuTorrent.Drop()
}