package main

import (
	"log/slog"
	"os"
	"regexp"
	"time"

	"git.sbstp.ca/sbstp/qbittorrent-sentinel/api"
	"github.com/samber/lo"
)

var rxExecutable = regexp.MustCompile(`\.(exe|scr|lnk|bat|vbs|js|cmd)$`)

func isExecutable(t *api.TorrentFile) bool {
	// - File has extension commonly used for viruses/executables
	return rxExecutable.MatchString(t.Name)
}

func isCandidate(t *api.TorrentInfo) bool {
	// - Less downloaded than total size, indicates it's stalled
	// - Size is less than total size, indicates some files have been filtered out
	return t.Downloaded < t.TotalSize && t.Size < t.TotalSize && time.Since(t.AddedOn.Time) > time.Minute*15
}

func checkTorrents(baseURL, username, password string) error {
	client, err := api.NewClient(baseURL, username, password)
	if err != nil {
		slog.Error("Could not connect to qBittorrent", slog.String("error", err.Error()))
		return err
	}

	list, err := client.LisTorrents()
	if err != nil {
		slog.Error("Could not list torrents", slog.String("error", err.Error()))
		return err
	}
	slog.Info("Successfully listed torrents", slog.Int("num", len(list)))

	for _, t := range list {
		if isCandidate(&t) {
			slog.Info("Torrent is a candidate", slog.String("hash", t.Hash), slog.String("name", t.Name))
			files, err := client.TorrentFiles(t.Hash)
			if err != nil {
				slog.Error("Could not get torrent files", slog.String("error", err.Error()))
				continue
			}

			executables := lo.Filter(files, func(f api.TorrentFile, _ int) bool {
				return isExecutable(&f)
			})
			if len(executables) > 0 {
				slog.Info("Torrent contains executables")
				for _, exe := range executables {
					slog.Info("Torrent file is executable", slog.String("name", exe.Name))
				}
				slog.Info("Deleting torrent...")
				if err := client.DeleteTorrent(t.Hash, true); err != nil {
					slog.Error("Failed to delete torrent", slog.String("error", err.Error()))
				} else {
					slog.Info("Torrent deleted successfully")
				}
			}

		}

	}

	slog.Info("Done")
	return nil
}

func main() {
	baseURL := os.Getenv("QBITTORRENT_BASE_URL")
	username := os.Getenv("QBITTORRENT_USERNAME")
	password := os.Getenv("QBITTORRENT_PASSWORD")

	if len(baseURL) == 0 {
		slog.Error("QBITTORRENT_BASE_URL environment variable is required")
		os.Exit(2)
	}

	if err := checkTorrents(baseURL, username, password); err != nil {
		os.Exit(1)
	}
}