// This function converts Windows date/time pattern format [1][2] into LDML date
// format pattern [3].
//
// i.e.
// We set h, H, m, s, d, dd, M, or y as is. They have same meaning in both of
// Windows and LDML.
// We need to convert the following patterns:
// t -> a
// tt -> a
// ddd -> EEE
// dddd -> EEEE
// g -> G
// gg -> ignore
//
// [1] http://msdn.microsoft.com/en-us/library/dd317787(v=vs.85).aspx
// [2] http://msdn.microsoft.com/en-us/library/dd318148(v=vs.85).aspx
// [3] LDML http://unicode.org/reports/tr35/tr35-6.html#Date_Format_Patterns
static String convertWindowsDateTimeFormat(const String& format)
{
StringBuilder converted;
StringBuilder literalBuffer;
bool inQuote = false;
bool lastQuoteCanBeLiteral = false;
for (unsigned i = 0; i < format.length(); ++i) {
UChar ch = format[i];
if (inQuote) {
if (ch == '\'') {
inQuote = false;
ASSERT(i);
if (lastQuoteCanBeLiteral && format[i - 1] == '\'') {
literalBuffer.append('\'');
lastQuoteCanBeLiteral = false;
} else
lastQuoteCanBeLiteral = true;
} else
literalBuffer.append(ch);
continue;
}
if (ch == '\'') {
inQuote = true;
if (lastQuoteCanBeLiteral && i > 0 && format[i - 1] == '\'') {
literalBuffer.append(ch);
lastQuoteCanBeLiteral = false;
} else
lastQuoteCanBeLiteral = true;
} else if (isASCIIAlpha(ch)) {
commitLiteralToken(literalBuffer, converted);
unsigned symbolStart = i;
unsigned count = countContinuousLetters(format, i);
i += count - 1;
if (ch == 'h' || ch == 'H' || ch == 'm' || ch == 's' || ch == 'M' || ch == 'y')
converted.append(format, symbolStart, count);
else if (ch == 'd') {
if (count <= 2)
converted.append(format, symbolStart, count);
else if (count == 3)
converted.append("EEE");
else
converted.append("EEEE");
} else if (ch == 'g') {
if (count == 1)
converted.append('G');
else {
// gg means imperial era in Windows.
// Just ignore it.
}
} else if (ch == 't')
converted.append('a');
else
literalBuffer.append(format, symbolStart, count);
} else
literalBuffer.append(ch);
}
commitLiteralToken(literalBuffer, converted);
return converted.toString();
}
// See http://msdn.microsoft.com/en-us/library/dd317787(v=vs.85).aspx
static Vector<DateFormatToken> parseDateFormat(const String format)
{
Vector<DateFormatToken> tokens;
StringBuilder literalBuffer;
bool inQuote = false;
for (unsigned i = 0; i < format.length(); ++i) {
UChar ch = format[i];
if (inQuote) {
if (ch == '\'') {
inQuote = false;
ASSERT(i);
if (format[i - 1] == '\'')
literalBuffer.append('\'');
} else
literalBuffer.append(ch);
continue;
}
if (ch == '\'') {
inQuote = true;
if (i > 0 && format[i - 1] == '\'')
literalBuffer.append(ch);
} else if (isYearSymbol(ch)) {
commitLiteralToken(literalBuffer, tokens);
unsigned count = countContinuousLetters(format, i);
i += count - 1;
if (count == 1)
tokens.append(DateFormatToken(DateFormatToken::Year1));
else if (count == 2)
tokens.append(DateFormatToken(DateFormatToken::Year2));
else
tokens.append(DateFormatToken(DateFormatToken::Year4));
} else if (isMonthSymbol(ch)) {
commitLiteralToken(literalBuffer, tokens);
unsigned count = countContinuousLetters(format, i);
i += count - 1;
if (count == 1)
tokens.append(DateFormatToken(DateFormatToken::Month1));
else if (count == 2)
tokens.append(DateFormatToken(DateFormatToken::Month2));
else if (count == 3)
tokens.append(DateFormatToken(DateFormatToken::Month3));
else
tokens.append(DateFormatToken(DateFormatToken::Month4));
} else if (isDaySymbol(ch)) {
commitLiteralToken(literalBuffer, tokens);
unsigned count = countContinuousLetters(format, i);
i += count - 1;
if (count == 1)
tokens.append(DateFormatToken(DateFormatToken::Day1));
else
tokens.append(DateFormatToken(DateFormatToken::Day2));
} else if (isEraSymbol(ch)) {
// Just ignore era.
// HTML5 date supports only A.D.
} else
literalBuffer.append(ch);
}
commitLiteralToken(literalBuffer, tokens);
return tokens;
}