/// <summary>
/// Pack an <see cref="EmvTags"/> object into a byte array
/// </summary>
/// <param name="tags">
/// The tags
/// </param>
/// <returns>
/// The packed byte array
/// </returns>
public static byte[] Pack(this EmvTags tags)
{
var stream = new MemoryStream();
foreach (var kvp in tags)
{
var field = PackField(kvp.Key, kvp.Value);
stream.Write(field, 0, field.Length);
}
return(stream.ToArray());
}
/// <summary>
/// Unpack a byte array into an <see cref="EmvTags"/> object
/// </summary>
/// <param name="msg">
/// The data
/// </param>
/// <returns>
/// The <see cref="EmvTags"/> object
/// </returns>
public static EmvTags UnpackEmvTags(byte[] msg)
{
var emvTags = new EmvTags();
var stream = new MemoryStream(msg);
while (stream.Position < stream.Length)
{
var tagValue = stream.ReadByte();
// Extended tag
if ((tagValue & 0x1F) == 0x1F)
{
tagValue <<= 8;
tagValue += stream.ReadByte();
}
var tag = (Tag)tagValue;
var length = stream.ReadByte();
if (length > 127)
{
int lengthOfLength = length - 128;
stream.Seek(lengthOfLength, SeekOrigin.Current);
length = stream.ReadByte();
}
byte[] data = null;
if (length > 0)
{
data = new byte[length];
stream.Read(data, 0, length);
}
emvTags.Add(tag, data);
}
return(emvTags);
}