package main

import (
	"bufio"
	"encoding/gob"
	"encoding/hex"
	"fmt"
	"io"
	"os"
	"os/exec"
	"strconv"
	"strings"

	"github.com/dustin/go-humanize"
	"go.stargrave.org/rutrackerer"
)

func main() {
	cmd := exec.Command("grep", append([]string{"-n"}, os.Args[1:]...)...)
	grepStdin, err := cmd.StdinPipe()
	if err != nil {
		panic(err)
	}
	grepStdout, err := cmd.StdoutPipe()
	if err != nil {
		panic(err)
	}
	if err = cmd.Start(); err != nil {
		panic(err)
	}
	torrents := make([]*rutrackerer.Torrent, 0, 1<<20)
	printer := make(chan struct{})
	go func() {
		scanner := bufio.NewScanner(grepStdout)
		var t string
		var i int
		var err error
		var torrent *rutrackerer.Torrent
		for scanner.Scan() {
			t = scanner.Text()
			i = strings.IndexByte(t, ':')
			i, err = strconv.Atoi(t[:i])
			if err != nil {
				panic(err)
			}
			torrent = torrents[i-1]
			fmt.Printf(
				`%s
	%s %s %d
	https://rutracker.org/forum/viewtopic.php?t=%d
	magnet:?xt=urn:btih:%s
`,
				torrent.Title,
				torrent.Registered.Format("2006-01-02T15:04:05"),
				humanize.IBytes(uint64(torrent.Size)),
				torrent.Offset,
				torrent.Id,
				strings.ToUpper(hex.EncodeToString(torrent.Hash[:])),
			)
		}
		if err = scanner.Err(); err != nil {
			panic(err)
		}
		close(printer)
	}()
	gobDec := gob.NewDecoder(bufio.NewReader(os.Stdin))
	for {
		var torrent rutrackerer.Torrent
		if err = gobDec.Decode(&torrent); err != nil {
			if err == io.EOF {
				break
			}
			panic(err)
		}
		torrents = append(torrents, &torrent)
		if _, err = grepStdin.Write([]byte(torrent.Title + "\n")); err != nil {
			panic(err)
		}
	}
	grepStdin.Close()
	<-printer
	if err = cmd.Wait(); err != nil {
		panic(err)
	}
}