/// <summary>
/// Function that implements the ToUnicode operation as defined in the IDNA
/// RFC. This operation is done on <b>single labels</b> before sending it to
/// something that expects Unicode names. A label is an individual part of a
/// domain name. Labels are usually separated by dots; for
/// e.g." "www.example.com" is composed of 3 labels "www","example", and
/// "com".
/// </summary>
///
/// <param name="src">The input string as UCharacterIterator to be processed</param>
/// <param name="options">A bit set of options: - IDNA.DEFAULT Use default options,i.e., do not process unassigned code points and do not useSTD3 ASCII rules If unassigned code points are found theoperation fails with ParseException.- IDNA.ALLOW_UNASSIGNED Unassigned values can be converted toASCII for query operations If this option is set, theunassigned code points are in the input are treated as normalUnicode code points.- IDNA.USE_STD3_RULES Use STD3 ASCII rules for host namesyntax restrictions If this option is set and the input doesnot satisfy STD3 rules, the operation will fail withParseException</param>
/// <returns>StringBuffer the converted String</returns>
/// <exception cref="ParseException"></exception>
/// @stable ICU 2.8
public static StringBuilder ConvertToUnicode(UCharacterIterator src,
int options)
{
bool[] caseFlags = null;
// the source contains all ascii codepoints
bool srcIsASCII = true;
// assume the source contains all LDH codepoints
// boolean srcIsLDH = true;
// get the options
// boolean useSTD3ASCIIRules = ((options & USE_STD3_RULES) != 0);
// int failPos = -1;
int ch;
int saveIndex = src.GetIndex();
// step 1: find out if all the codepoints in src are ASCII
while ((ch = src.Next()) != IBM.ICU.Text.UForwardCharacterIterator_Constants.DONE)
{
if (ch > 0x7F)
{
srcIsASCII = false;
} /*
* else if((srcIsLDH = isLDHChar(ch))==false){ failPos =
* src.getIndex(); }
*/
}
StringBuilder processOut;
if (srcIsASCII == false)
{
try {
// step 2: process the string
src.SetIndex(saveIndex);
processOut = singleton.namePrep.Prepare(src, options);
} catch (StringPrepParseException ex) {
return(new StringBuilder(src.GetText()));
}
}
else
{
// just point to source
processOut = new StringBuilder(src.GetText());
}
// TODO:
// The RFC states that
// <quote>
// ToUnicode never fails. If any step fails, then the original input
// is returned immediately in that step.
// </quote>
// step 3: verify ACE Prefix
if (StartsWithPrefix(processOut))
{
StringBuilder decodeOut = null;
// step 4: Remove the ACE Prefix
String temp = processOut.ToString(ACE_PREFIX.Length, processOut.Length - ACE_PREFIX.Length);
// step 5: Decode using punycode
try {
decodeOut = IBM.ICU.Text.Punycode.Decode(new StringBuilder(temp), caseFlags);
} catch (StringPrepParseException e) {
decodeOut = null;
}
// step 6:Apply toASCII
if (decodeOut != null)
{
StringBuilder toASCIIOut = ConvertToASCII(decodeOut, options);
// step 7: verify
if (CompareCaseInsensitiveASCII(processOut, toASCIIOut) != 0)
{
// throw new
// StringPrepParseException("The verification step prescribed by the RFC 3491 failed",
// StringPrepParseException.VERIFICATION_ERROR);
decodeOut = null;
}
}
// step 8: return output of step 5
if (decodeOut != null)
{
return(decodeOut);
}
}
// }else{
// // verify that STD3 ASCII rules are satisfied
// if(useSTD3ASCIIRules == true){
// if( srcIsLDH == false /* source contains some non-LDH characters */
// || processOut.charAt(0) == HYPHEN
// || processOut.charAt(processOut.length()-1) == HYPHEN){
//
// if(srcIsLDH==false){
// throw new
// StringPrepParseException("The input does not conform to the STD 3 ASCII rules",
// StringPrepParseException.STD3_ASCII_RULES_ERROR,processOut.toString(),
// (failPos>0) ? (failPos-1) : failPos);
// }else if(processOut.charAt(0) == HYPHEN){
// throw new
// StringPrepParseException("The input does not conform to the STD 3 ASCII rules",
// StringPrepParseException.STD3_ASCII_RULES_ERROR,
// processOut.toString(),0);
//
// }else{
// throw new
// StringPrepParseException("The input does not conform to the STD 3 ASCII rules",
// StringPrepParseException.STD3_ASCII_RULES_ERROR,
// processOut.toString(),
// processOut.length());
//
// }
// }
// }
// // just return the source
// return new StringBuffer(src.getText());
// }
return(new StringBuilder(src.GetText()));
}
/// <summary>
/// This function implements the ToASCII operation as defined in the IDNA
/// RFC. This operation is done on <b>single labels</b> before sending it to
/// something that expects ASCII names. A label is an individual part of a
/// domain name. Labels are usually separated by dots;
/// e.g." "www.example.com" is composed of 3 labels "www","example", and
/// "com".
/// </summary>
///
/// <param name="src">The input string as UCharacterIterator to be processed</param>
/// <param name="options">A bit set of options: - IDNA.DEFAULT Use default options,i.e., do not process unassigned code points and do not useSTD3 ASCII rules If unassigned code points are found theoperation fails with ParseException.- IDNA.ALLOW_UNASSIGNED Unassigned values can be converted toASCII for query operations If this option is set, theunassigned code points are in the input are treated as normalUnicode code points.- IDNA.USE_STD3_RULES Use STD3 ASCII rules for host namesyntax restrictions If this option is set and the input doesnot satisfy STD3 rules, the operation will fail withParseException</param>
/// <returns>StringBuffer the converted String</returns>
/// <exception cref="ParseException"></exception>
/// @stable ICU 2.8
public static StringBuilder ConvertToASCII(UCharacterIterator src,
int options)
{
bool[] caseFlags = null;
// the source contains all ascii codepoints
bool srcIsASCII = true;
// assume the source contains all LDH codepoints
bool srcIsLDH = true;
// get the options
bool useSTD3ASCIIRules = ((options & USE_STD3_RULES) != 0);
int ch;
// step 1
while ((ch = src.Next()) != IBM.ICU.Text.UForwardCharacterIterator_Constants.DONE)
{
if (ch > 0x7f)
{
srcIsASCII = false;
}
}
int failPos = -1;
src.SetToStart();
StringBuilder processOut = null;
// step 2 is performed only if the source contains non ASCII
if (!srcIsASCII)
{
// step 2
processOut = singleton.namePrep.Prepare(src, options);
}
else
{
processOut = new StringBuilder(src.GetText());
}
int poLen = processOut.Length;
if (poLen == 0)
{
throw new StringPrepParseException(
"Found zero length lable after NamePrep.",
IBM.ICU.Text.StringPrepParseException.ZERO_LENGTH_LABEL);
}
StringBuilder dest = new StringBuilder();
// reset the variable to verify if output of prepare is ASCII or not
srcIsASCII = true;
// step 3 & 4
for (int j = 0; j < poLen; j++)
{
ch = processOut[j];
if (ch > 0x7F)
{
srcIsASCII = false;
}
else if (IsLDHChar(ch) == false)
{
// here we do not assemble surrogates
// since we know that LDH code points
// are in the ASCII range only
srcIsLDH = false;
failPos = j;
}
}
if (useSTD3ASCIIRules == true)
{
// verify 3a and 3b
if (srcIsLDH == false || /* source contains some non-LDH characters */
processOut[0] == HYPHEN ||
processOut[processOut.Length - 1] == HYPHEN)
{
/* populate the parseError struct */
if (srcIsLDH == false)
{
throw new StringPrepParseException(
"The input does not conform to the STD 3 ASCII rules",
IBM.ICU.Text.StringPrepParseException.STD3_ASCII_RULES_ERROR,
processOut.ToString(),
(failPos > 0) ? (failPos - 1) : failPos);
}
else if (processOut[0] == HYPHEN)
{
throw new StringPrepParseException(
"The input does not conform to the STD 3 ASCII rules",
IBM.ICU.Text.StringPrepParseException.STD3_ASCII_RULES_ERROR,
processOut.ToString(), 0);
}
else
{
throw new StringPrepParseException(
"The input does not conform to the STD 3 ASCII rules",
IBM.ICU.Text.StringPrepParseException.STD3_ASCII_RULES_ERROR,
processOut.ToString(), (poLen > 0) ? poLen - 1
: poLen);
}
}
}
if (srcIsASCII)
{
dest = processOut;
}
else
{
// step 5 : verify the sequence does not begin with ACE prefix
if (!StartsWithPrefix(processOut))
{
// step 6: encode the sequence with punycode
caseFlags = new bool[poLen];
StringBuilder punyout = IBM.ICU.Text.Punycode.Encode(processOut, caseFlags);
// convert all codepoints to lower case ASCII
StringBuilder lowerOut = ToASCIILower(punyout);
// Step 7: prepend the ACE prefix
dest.Append(ACE_PREFIX, 0, ACE_PREFIX.Length);
// Step 6: copy the contents in b2 into dest
dest.Append(lowerOut);
}
else
{
throw new StringPrepParseException(
"The input does not start with the ACE Prefix.",
IBM.ICU.Text.StringPrepParseException.ACE_PREFIX_ERROR,
processOut.ToString(), 0);
}
}
if (dest.Length > MAX_LABEL_LENGTH)
{
throw new StringPrepParseException(
"The labels in the input are too long. Length > 63.",
IBM.ICU.Text.StringPrepParseException.LABEL_TOO_LONG_ERROR,
dest.ToString(), 0);
}
return(dest);
}