/// <summary>
/// Initializes a new instance of the <see cref="Base58"/> class
/// using a custom alphabet.
/// </summary>
/// <param name="alphabet">Alphabet to use.</param>
public Base58(Base58Alphabet alphabet)
{
this.Alphabet = alphabet;
this.ZeroChar = alphabet.Value[0];
}
public Base58(Base58Alphabet alphabet)
{
Require.NotNull(alphabet, "alphabet");
this.alphabet = alphabet;
}
/// <summary>
/// Encode to Base58 representation.
/// </summary>
/// <param name="bytes">Bytes to encode.</param>
/// <returns>Encoded string.</returns>
public unsafe string Encode(ReadOnlySpan <byte> bytes)
{
int bytesLen = bytes.Length;
if (bytesLen == 0)
{
return(string.Empty);
}
fixed(byte *inputPtr = bytes)
fixed(char *alphabetPtr = this.Alphabet.Value)
{
byte *pInput = inputPtr;
byte *pEnd = inputPtr + bytesLen;
while (pInput != pEnd && *pInput == 0)
{
pInput++;
}
int numZeroes = (int)(pInput - inputPtr);
char zeroChar = alphabetPtr[0];
if (pInput == pEnd)
{
return(new string(zeroChar, numZeroes));
}
// we can safely use char count for allocating a byte buffer for the numeric representation
// because each digit will map to a single character later in the encoding process.
int outputLen = Base58Alphabet.GetAllocationCharCountForEncoding(bytesLen, numZeroes);
int length = 0;
byte[] output = new byte[outputLen];
fixed(byte *outputPtr = output)
{
byte *pOutputEnd = outputPtr + outputLen - 1;
while (pInput != pEnd)
{
int carry = *pInput;
int i = 0;
for (byte *pDigit = pOutputEnd; (carry != 0 || i < length) &&
pDigit >= outputPtr; pDigit--, i++)
{
carry += 256 * (*pDigit);
carry = Math.DivRem(carry, 58, out int remainder);
*pDigit = (byte)remainder;
}
length = i;
pInput++;
}
pOutputEnd++;
byte *pOutput = outputPtr;
while (pOutput != pOutputEnd && *pOutput == 0)
{
pOutput++;
}
int resultLen = numZeroes + (int)(pOutputEnd - pOutput);
string result = new string(zeroChar, resultLen);
fixed(char *resultPtr = result)
{
char *pResult = resultPtr + numZeroes;
while (pOutput != pOutputEnd)
{
*pResult++ = alphabetPtr[*pOutput++];
}
}
return(result);
}
}
}
/// <summary>
/// Initializes a new instance of the <see cref="Base58"/> class
/// using a custom alphabet.
/// </summary>
/// <param name="alphabet">Alphabet to use.</param>
public Base58(Base58Alphabet alphabet)
{
this.Alphabet = alphabet;
}
public Base58(Base58Alphabet alphabet)
{
Require.NotNull(alphabet, nameof(alphabet));
this.alphabet = alphabet;
}