From 4a0d1a288b2d6fe8e3bdb77cac1762ef69dd91bf Mon Sep 17 00:00:00 2001
From: firebadnofire <william@archuser.org>
Date: Sun, 4 May 2025 13:30:55 -0400
Subject: [PATCH] RC1

---
 main.go | 77 ++++++++++++++++++++++++++++++++++++++-------------------
 1 file changed, 52 insertions(+), 25 deletions(-)

diff --git a/main.go b/main.go
index 58ea3ef..ab4bc93 100644
--- a/main.go
+++ b/main.go
@@ -1,31 +1,47 @@
 package main
 
 import (
+	"context"
+	"flag"
 	"fmt"
 	"log"
 	"os"
-	"strings"
+	"path/filepath"
+	"regexp"
 	"time"
 
 	"github.com/anacrolix/torrent"
 )
 
+var invalidFilenameChars = regexp.MustCompile(`[<>:"/\\|?*\x00-\x1F]`)
+
+// sanitizeFilename replaces invalid filesystem characters with underscores.
+func sanitizeFilename(name string) string {
+	return invalidFilenameChars.ReplaceAllString(name, "_")
+}
+
 func main() {
-	if len(os.Args) < 2 {
-		fmt.Println("Usage: ./magnet-to-torrent \"magnet_link\" [output.torrent]")
+	// Command-line flags
+	output := flag.String("o", "", "Output .torrent filename (optional)")
+	timeout := flag.Duration("timeout", 5*time.Minute, "Timeout for metadata retrieval")
+	upload := flag.Bool("upload", false, "Allow uploading (seeding) after metadata retrieval")
+
+	flag.Usage = func() {
+		fmt.Fprintf(flag.CommandLine.Output(), "Usage: %s [options] magnet_link\nOptions:\n", os.Args[0])
+		flag.PrintDefaults()
+	}
+	flag.Parse()
+
+	if flag.NArg() < 1 {
+		flag.Usage()
 		os.Exit(1)
 	}
+	magnetLink := flag.Arg(0)
 
-	magnetLink := os.Args[1]
-	outputFile := ""
-
-	if len(os.Args) == 3 {
-		outputFile = os.Args[2]
-	}
-
+	// Configure torrent client
 	clientConfig := torrent.NewDefaultClientConfig()
 	clientConfig.DataDir = os.TempDir()
-	clientConfig.NoUpload = true
+	clientConfig.NoUpload = !*upload
 
 	client, err := torrent.NewClient(clientConfig)
 	if err != nil {
@@ -33,35 +49,46 @@ func main() {
 	}
 	defer client.Close()
 
+	// Add magnet link
 	t, err := client.AddMagnet(magnetLink)
 	if err != nil {
 		log.Fatalf("Error adding magnet link: %v", err)
 	}
 
-	<-t.GotInfo()
-	info := t.Metainfo()
+	// Wait for metadata with timeout
+	ctx, cancel := context.WithTimeout(context.Background(), *timeout)
+	defer cancel()
 
-	if outputFile == "" {
-		outputFile = strings.ReplaceAll(t.Name(), " ", "_") + ".torrent"
+	select {
+	case <-t.GotInfo():
+		// Metadata received
+	case <-ctx.Done():
+		log.Fatalf("Timeout waiting for metadata after %v", *timeout)
 	}
 
-	f, err := os.Create(outputFile)
+	info := t.Metainfo()
+
+	// Determine output filename
+	outFile := *output
+	if outFile == "" {
+		base := sanitizeFilename(t.Name())
+		outFile = base + ".torrent"
+	}
+	outFile = filepath.Clean(outFile)
+
+	// Write .torrent file
+	f, err := os.Create(outFile)
 	if err != nil {
-		log.Fatalf("Error creating file: %v", err)
+		log.Fatalf("Error creating file %s: %v", outFile, err)
 	}
 	defer f.Close()
 
-	err = info.Write(f)
-	if err != nil {
+	if err := info.Write(f); err != nil {
 		log.Fatalf("Error writing torrent file: %v", err)
 	}
 
-	fmt.Printf("Torrent metadata saved to %s\n", outputFile)
+	fmt.Printf("Torrent metadata saved to %s\n", outFile)
 
+	// Drop the torrent handle; client will close via defer
 	t.Drop()
-	client.Close()
-
-	// Give client some time to gracefully close
-	time.Sleep(2 * time.Second)
 }
-