public string Decode(string pSource)
{
string label = null;
string[] labelArray = null;
StringBuilder buffer = null;
EncodingOption option = null;
UTF32String decoded = null;
// check if we have encoder or not
if (null == m_converter)
{
return(null);
}
if (null == pSource)
{
return(null);
}
// Initializes
buffer = new StringBuilder();
option = new EncodingOption();
// SHOULD ONLY contain FULL_STOP as seperator(RFC3492)
labelArray = pSource.Split('.');
// for each label do the decoding
for (int index = 0; index < labelArray.Length; index++)
{
label = labelArray[index];
decoded = StringUtil.Normalize(this.Decode(label, option));
if (null == decoded)
{
throw new ACEException(string.Format("Decoding error, empty label: {0}", pSource));
}
// append the decoded
buffer.Append(decoded.ToUTF16());
if (index < (labelArray.Length - 1))
{
// Based on RFC3492, only allow FULL_STOP in
// string as seperator after decoding
buffer.Append(".");
}
}
// return the decoded string
return(buffer.ToString());
}
//---------------------------------------------------------------------
// Public methods
//---------------------------------------------------------------------
public override string Encode(UTF32String pSource, bool[] pCaseFlag)
{
string source = null;
byte[] compressed = null;
// get the UTF16 string
source = pSource.ToUTF16();
// compress
compressed = this.Compress(source);
// Base32 encoding
return(Base32.Encode(compressed));
}
private UTF32String Decode(string pSource, IEncodingOption pOption)
{
string check = null;
UTF32String decoded = null;
UTF32String source = null;
try
{
// Initializes
source = new UTF32String(pSource);
// Step #1-2
if (!Converter.IsAllAscii(source) && (null != m_preparer))
{
source = m_preparer.Prepare(source, pOption);
}
// Step #3-5
if (null != m_converter)
{
decoded = m_converter.Decode(source.ToUTF16(), new bool[source.Length]);
}
// Step #6-7
if (pOption.IsOptionSet(EncodingOption.DECODE_DOUBLE_CHECK))
{
check = this.Encode(decoded, pOption);
if (0 != string.Compare(check, pSource, true))
{
throw new ACEException("Decoding round trip check failed");
}
}
}
catch (Exception e)
{
// Based on RFC3492, decode never fails.
// check if we need to allow decode fail
if (pOption.IsOptionSet(EncodingOption.ALLOW_DECODE_FAIL))
{
throw e;
}
decoded = new UTF32String(pSource);
}
// Step #8
return(decoded);
}
//---------------------------------------------------------------------
// Private methods
//---------------------------------------------------------------------
private string Encode(UTF32String pSource, IEncodingOption pOption)
{
bool bAllAscii = false;
string encoded = null;
UTF32String prepared = null;
// Step #1: set the flag, all ascii?
bAllAscii = Converter.IsAllAscii(pSource);
// Step #2
if (!bAllAscii)
{
// check if we need to prepare the string
if (null != m_preparer)
{
prepared = m_preparer.Prepare(pSource, pOption);
}
else
{
prepared = pSource;
}
}
// Step #3: check if we need to apply the rules
if (pOption.IsOptionSet(EncodingOption.USE_STD3_RULES))
{
// failed on Dns compatible?
if (!Converter.IsAllDnsCompatible(prepared))
{
throw new Std3RuleCodePointException(string.Format("The input does not conform to the STD 3 ASCII rules(DNS Compatible): {0}", prepared.ToString()));
}
if (0 < prepared.Length)
{
// first char is hyphen?
if (prepared[0] == Converter.CHAR_HYPHEN)
{
throw new Std3RuleCodePointException(string.Format("The input does not conform to the STD 3 ASCII rules(Hyphen at the beginning): {0}", prepared.ToString()));
}
// last char is hyphen?
if (prepared[prepared.Length - 1] == Converter.CHAR_HYPHEN)
{
throw new Std3RuleCodePointException(string.Format("The input does not conform to the STD 3 ASCII rules(Hyphen at the end): {0}", prepared.ToString()));
}
}
}
//Step #4: check if it's all ascii already
if (!bAllAscii)
{
// Step #5: check if it begin with the 'prefix'
if (m_converter.IsBeginWithPrefix(prepared))
{
throw new ACEException(string.Format("The input can't begin with an ACE prefix: {0}", pSource.ToString()));
}
// Step #6:
encoded = m_converter.Encode(prepared, new bool[prepared.Length]);
//Step #7: insert the prefix
encoded = encoded.Insert(0, m_converter.Prefix);
}
else
{
encoded = pSource.ToUTF16();
}
// Step #8
if (encoded.Length > Converter.LABEL_MAX_LENGTH)
{
throw new ACEException(string.Format("Encoded name too long: {0}", encoded.Length));
}
// Done
return(encoded);
}
