/// <summary>
/// Get the single file mode meta information
/// </summary>
/// <param name="rootNode">the root node of torrent</param>
/// <param name="infoNode">the info node of torrent</param>
/// <returns>Return the single file mode meta information</returns>
private static SingleFileMetaInfo GetSingleFileMetaInfo(DictNode rootNode, DictNode infoNode)
{
SingleFileMetaInfo result = new SingleFileMetaInfo();
DecodeRootNode(result, rootNode);
DecodeInfoNode(result, infoNode);
BytesNode nameNode = infoNode["name"] as BytesNode;
Debug.Assert(nameNode != null);
result.Name = nameNode.StringText;
IntNode lengthNode = infoNode["length"] as IntNode;
Debug.Assert(lengthNode != null);
result.Length = lengthNode.Value;
if (infoNode.ContainsKey("md5sum"))
{
BytesNode md5SumNode = infoNode["md5sum"] as BytesNode;
Debug.Assert(md5SumNode != null);
result.Md5Sum = md5SumNode.StringText;
}
else
{
result.Md5Sum = String.Empty;
}
return(result);
}
/// <summary>
/// Parse meta-info from torrent file.
/// </summary>
/// <param name="fileName">The filename of torrent</param>
/// <returns>Return the metainfo</returns>
public static MetaInfo Parse(string fileName)
{
MetaInfo result = null;
DictNode rootNode;
byte[] source;
if (File.Exists(fileName))
{
source = File.ReadAllBytes(fileName);
rootNode = BEncodingFactory.Decode(source) as DictNode;
Debug.Assert(rootNode != null);
}
else
{
return(null);
}
DictNode infoNode = rootNode["info"] as DictNode;
Debug.Assert(infoNode != null);
if (infoNode.ContainsKey("length"))
{
result = GetSingleFileMetaInfo(rootNode, infoNode);
}
else
{
result = GetMultiFileMetaInfo(rootNode, infoNode);
}
result.InfoHash = Globals.GetSha1Hash(BEncodingFactory.ByteArrayEncode(rootNode["info"]));//Globals.Sha1.ComputeHash(BEncodingFactory.ByteArrayEncode(rootNode["info"]));
return(result);
}
private static void DecodeInfoNode(MetaInfo metaInfo, DictNode infoNode)
{
IntNode pieceLengthNode = infoNode["piece length"] as IntNode;
Debug.Assert(pieceLengthNode != null);
metaInfo.PieceLength = pieceLengthNode.IntValue;
BytesNode piecesNode = infoNode["pieces"] as BytesNode;
Debug.Assert(piecesNode != null);
metaInfo.SetFullHashValues(piecesNode.ByteArray);
if (infoNode.ContainsKey("private"))
{
IntNode privateNode = infoNode["private"] as IntNode;
Debug.Assert(privateNode != null);
metaInfo.Private = privateNode.Value == 1;
}
}
private static void DecodeRootNode(MetaInfo metaInfo, DictNode rootNode)
{
BytesNode annouceNode = rootNode["announce"] as BytesNode;
Debug.Assert(annouceNode != null);
metaInfo.Announce = annouceNode.StringText;
if (rootNode.ContainsKey("announce-list"))
{
ListNode announceListNode = rootNode["announce-list"] as ListNode;
Debug.Assert(announceListNode != null);
foreach (ListNode announceArrayNode in announceListNode)
{
Debug.Assert(announceArrayNode != null);
IList <string> announceArray = new List <string>();
foreach (BytesNode node in announceArrayNode)
{
Debug.Assert(node != null);
announceArray.Add(node.StringText);
}
metaInfo.AddAnnounceArray(announceArray);
}
}
if (rootNode.ContainsKey("creation date"))
{
IntNode creationDataNode = rootNode["creation date"] as IntNode;
Debug.Assert(creationDataNode != null);
metaInfo.CreationDate = creationDataNode.Value.FromUnixEpochFormat();
}
else
{
metaInfo.CreationDate = new DateTime(1970, 1, 1);
}
if (rootNode.ContainsKey("comment"))
{
BytesNode commentNode = rootNode["comment"] as BytesNode;
Debug.Assert(commentNode != null);
metaInfo.Comment = commentNode.StringText;
}
else
{
metaInfo.Comment = String.Empty;
}
if (rootNode.ContainsKey("created by"))
{
BytesNode createdByNode = rootNode["created by"] as BytesNode;
Debug.Assert(createdByNode != null);
metaInfo.CreatedBy = createdByNode.StringText;
}
else
{
metaInfo.CreatedBy = String.Empty;
}
if (rootNode.ContainsKey("encoding"))
{
BytesNode encodingNode = rootNode["encoding"] as BytesNode;
Debug.Assert(encodingNode != null);
metaInfo.Encoding = encodingNode.StringText;
}
else
{
metaInfo.Encoding = "ASCII";
}
}
/// <summary>
/// Get the multi file mode meta information
/// </summary>
/// <param name="rootNode">the root node of torrent</param>
/// <param name="infoNode">the info node of torrent</param>
/// <returns>Return the multi file mode meta information</returns>
private static MultiFileMetaInfo GetMultiFileMetaInfo(DictNode rootNode, DictNode infoNode)
{
MultiFileMetaInfo result = new MultiFileMetaInfo();
DecodeRootNode(result, rootNode);
DecodeInfoNode(result, infoNode);
BytesNode nameNode = infoNode["name"] as BytesNode;
Debug.Assert(nameNode != null);
result.Name = nameNode.StringText;
ListNode filesNode = infoNode["files"] as ListNode;
Debug.Assert(filesNode != null);
long begin = 0;
FileInfo[] fileInfoArray = new FileInfo[filesNode.Count];
for (int i = 0; i < filesNode.Count; i++)
{
DictNode node = filesNode[i] as DictNode;
IntNode lengthNode = node["length"] as IntNode;
Debug.Assert(lengthNode != null);
FileInfo fileInfo = new FileInfo();
fileInfo.Length = lengthNode.Value;
fileInfo.Begin = begin;
fileInfo.End = begin + fileInfo.Length;
begin = fileInfo.End;
ListNode pathNode = node["path"] as ListNode;
Debug.Assert(pathNode != null);
StringBuilder sb = new StringBuilder();
BytesNode firstPathNode = pathNode[0] as BytesNode;
Debug.Assert(firstPathNode != null);
sb.Append(firstPathNode.StringText);
for (int j = 1; j < pathNode.Count; j++)
{
BytesNode subPathNode = pathNode[j] as BytesNode;
Debug.Assert(subPathNode != null);
sb.AppendFormat(@"\{0}", subPathNode.StringText);
}
fileInfo.Path = sb.ToString();
if (!node.ContainsKey("md5sum"))
{
fileInfo.Md5Sum = String.Empty;
}
else
{
BytesNode md5SumNode = node["md5sum"] as BytesNode;
Debug.Assert(md5SumNode != null);
fileInfo.Md5Sum = md5SumNode.StringText;
}
fileInfoArray[i] = fileInfo;
}
result.SetFileInfoArray(fileInfoArray);
return(result);
}