/// <summary>
/// The decode.
/// </summary>
/// <param name="value">
/// The value.
/// </param>
/// <returns>
/// The <see cref="Tuple"/>.
/// </returns>
public static Tuple <int, int> Decode(int[] value)
{
if (value.Length < 3)
{
throw new ArgumentException("Given trits can not be Pascal decoded. Invalid length.");
}
if (value.Take(4).SequenceEqual(Zero))
{
return(new Tuple <int, int>(0, 4));
}
var encoderStart = End(value);
var inputEnd = encoderStart + (encoderStart / Constants.TritsPerTryte);
var encoder = Converter.TritsToInt(value.Skip(encoderStart).Take(inputEnd - encoderStart).ToArray());
var result = 0;
for (var i = 0; i < encoderStart / Constants.TritsPerTryte; i++)
{
var tritsIntValue = ((encoder >> i) & 1) != 0
? -Converter.TritsToInt(value.Skip(i * Constants.TritsPerTryte).Take(Constants.TritsPerTryte).ToArray())
: Converter.TritsToInt(value.Skip(i * Constants.TritsPerTryte).Take(Constants.TritsPerTryte).ToArray());
result = result + ((int)Math.Pow(27, i) * tritsIntValue);
}
return(new Tuple <int, int>(result, inputEnd));
}
/// <summary>
/// The end.
/// </summary>
/// <param name="input">
/// The input.
/// </param>
/// <returns>
/// The <see cref="int"/>.
/// </returns>
private static int End(int[] input)
{
if (Converter.TritsToInt(input.Take(Constants.TritsPerTryte).ToArray()) > 0)
{
return(Constants.TritsPerTryte);
}
return(Constants.TritsPerTryte + End(input.Skip(Constants.TritsPerTryte).ToArray()));
}
/// <summary>
/// The encode.
/// </summary>
/// <param name="value">
/// The value.
/// </param>
/// <returns>
/// The <see cref="int[]"/>.
/// </returns>
public static int[] Encode(int value)
{
if (value == 0)
{
return(Zero);
}
var length = RoundThird(CalculateMinimumTrits(Math.Abs(value), 1));
var trits = new int[EncodedLength(value)];
IntToTrits(value, trits);
var encoding = 0;
var index = 0;
for (var i = 0; i < length - Constants.TritsPerTryte; i += Constants.TritsPerTryte)
{
var tritValue = trits.Skip(i).Take(Constants.TritsPerTryte).ToArray();
var tritsAsInt = Converter.TritsToInt(tritValue);
if (tritsAsInt >= 0)
{
encoding |= 1 << index;
for (var j = 0; j < tritValue.Length; j++)
{
trits[i + j] = -tritValue[j];
}
}
index++;
}
if (Converter.TritsToInt(trits.Skip(length - Constants.TritsPerTryte).Take(length).ToArray()) < 0)
{
encoding |= 1 << index;
for (var i = 0; i < trits.Skip(length - Constants.TritsPerTryte).Take(length).ToArray().Length; i++)
{
trits[i + length - Constants.TritsPerTryte] = -trits[i + length - Constants.TritsPerTryte];
}
}
var checksumTrits = new int[trits.Length - length];
IntToTrits(encoding, checksumTrits);
for (var i = 0; i < checksumTrits.Length; i++)
{
trits[length + i] = checksumTrits[i];
}
return(trits);
}