/**
* Encodes a MIME header.
*
* XXX: preferences
*
* @param field_name header field name
* @param field_value header field value
* @param preferences
* @return encoded mime header
*/
public static StringValue encodeMime(Env env,
StringValue name,
StringValue value,
string inCharset,
string outCharset,
string scheme,
string lineBreakChars,
int lineLength)
{
Decoder decoder = Decoder.create(inCharset);
CharSequence nameUnicode = decoder.decode(env, name);
decoder.reset();
string valueUnicode = decoder.decode(env, value).ToString();
StringValue sb = env.createUnicodeBuilder();
sb.append(UnicodeUtility.encode(env, nameUnicode, outCharset));
sb.append(':');
sb.append(' ');
string word = encodeMimeWord(valueUnicode.ToString(),
outCharset,
scheme,
lineBreakChars,
lineLength);
sb.append(MimeUtility.fold(sb.length(), word));
return(sb);
}