private void ParseMagnetLink(string url)
{
var splitStr = url.Split('?');
if (splitStr.Length == 0 || splitStr[0] != "magnet:")
throw new FormatException("The magnet link must start with 'magnet:?'.");
if (splitStr.Length == 1)
return; //no parametter
var keyValuePairs = splitStr[1].Split('&', ';')
.Select(x => x.Split('='))
.Select(x => new {Key = x[0], Value = x[1], x.Length});
foreach (var keyValue in keyValuePairs)
{
if (keyValue.Length != 2)
throw new FormatException("A field-value pair of the magnet link contain more than one equal'.");
switch (keyValue.Key.Substring(0, 2))
{
case "xt": //exact topic
if (InfoHash != null)
throw new FormatException("More than one infohash in magnet link is not allowed.");
if (keyValue.Value.Length != 49 && keyValue.Value.Length != 41)
throw new FormatException("Infohash must be base32 or hex encoded.");
var val = keyValue.Value.Substring(9);
switch (keyValue.Value.Substring(0, 9))
{
case "urn:sha1:": //base32 hash
case "urn:btih:":
if (val.Length == 32)
InfoHash = InfoHash.FromBase32(val);
else if (val.Length == 40)
InfoHash = InfoHash.FromHex(val);
break;
}
break;
case "tr": //address tracker
AnnounceUrls.Add(keyValue.Value);
break;
case "as": //Acceptable Source
_webseeds.Add(keyValue.Value);
break;
case "dn": //display name
Name = keyValue.Value;
break;
case "xl": //exact length
case "xs": // eXact Source - P2P link.
case "kt": //keyword topic
case "mt": //manifest topic
//not supported for moment
break;
//not supported
}
}
}
