Make ParseMagnetURI easier to read

diff --git a/magnet.go b/magnet.go
index 4c3e137d5c9862557c795795b88728deb8f75e32..b326e1fc00bbea43951ae0e25f2188dd480f8cd2 100644 (file)
--- a/magnet.go
+++ b/magnet.go
@@ -30,6 +30,7 @@ func (m *Magnet) String() (ret string) {
        return
 }
 
+// ParseMagnetURI parses Magnet-formatted URIs into a Magnet instance
 func ParseMagnetURI(uri string) (m Magnet, err error) {
        u, err := url.Parse(uri)
        if err != nil {
@@ -45,22 +46,23 @@ func ParseMagnetURI(uri string) (m Magnet, err error) {
                err = fmt.Errorf("bad xt parameter")
                return
        }
-       xt = xt[len(xtPrefix):]
-       decode := func() func(dst, src []byte) (int, error) {
-               switch len(xt) {
-               case 40:
-                       return hex.Decode
-               case 32:
-                       return base32.StdEncoding.Decode
-               default:
-                       return nil
-               }
-       }()
+       infoHash := xt[len(xtPrefix):]
+
+       // BTIH hash can be in HEX or BASE32 encoding
+       // will assign apropriate func judging from symbol length
+       var decode func(dst, src []byte) (int, error)
+       switch len(infoHash) {
+       case 40:
+               decode = hex.Decode
+       case 32:
+               decode = base32.StdEncoding.Decode
+       }
+
        if decode == nil {
-               err = fmt.Errorf("unhandled xt parameter encoding: encoded length %d", len(xt))
+               err = fmt.Errorf("unhandled xt parameter encoding: encoded length %d", len(infoHash))
                return
        }
-       n, err := decode(m.InfoHash[:], []byte(xt))
+       n, err := decode(m.InfoHash[:], []byte(infoHash))
        if err != nil {
                err = fmt.Errorf("error decoding xt: %s", err)
                return