public async Task <Tag> GetNextTag(Stream stream)
{
Tag t = new Tag();
byte[] header = new byte[11];
byte[] remainder = new byte[4];
stream.Read(header, 0, 11);
t.Type = header[0];
t.PacketSize = header[1] << 16 | header[2] << 8 | header[3] & 255;
t.TimeStamp = (header[7] << 24 | header[4] << 16 | header[5] << 8 | header[6] & 255) & 0x7FFFFFFF;
t.Remainder = new byte[3];
Array.Copy(header, 8, t.Remainder, 0, 3);
byte[] data = new byte[t.PacketSize];
stream.Read(data, 0, t.PacketSize);
stream.Read(remainder, 0, 4);
Array.Reverse(remainder);
t.TotalSize = BitConverter.ToInt32(remainder, 0);
t.NeedDecryption = false;
if (t.Type == 10 || t.Type == 11)
{
t.Type -= 2;
byte tp = data[12];
int pos = 13;
if ((tp & 2) > 0)
{
pos += 16;
}
if ((tp & 4) > 0)
{
StringBuilder bld = new StringBuilder();
byte b = data[pos++];
while (b != 0)
{
bld.Append((char)b);
b = data[pos++];
}
string nurl = bld.ToString();
if (nurl != KeyUrl)
{
Uri bas = new Uri(baseurl);
string url = string.Format(FormatKey, bas.Scheme + "://" + bas.Host + nurl, guid, manifest.Pv20.Substring(1) + "&hdcore=3.2.0");
int idx = nurl.IndexOf("_");
keydata = nurl.Substring(idx);
WebStream ws = await GetStream(url);
if (ws == null || ws.StatusCode != HttpStatusCode.OK)
{
ws?.Dispose();
throw new IOException("Error " + ws.StatusCode + " trying to download fragment");
}
KeyData = new byte[ws.ContentLength];
await ws.ReadAsync(KeyData, 0, (int)ws.ContentLength);
ws.Dispose();
KeyUrl = nurl;
}
}
t.NeedDecryption = true;
t.Key = KeyData;
}
t.Packet = data;
t.PacketSize = data.Length;
return(t);
}