bool Nibbler::getDate (const std::string& format, time_t& t)
{
auto i = _cursor;
int month = -1; // So we can check later.
int day = -1;
int year = -1;
int hour = -1;
int minute = -1;
int second = -1;
// For parsing, unused.
int wday = -1;
int week = -1;
for (unsigned int f = 0; f < format.length (); ++f)
{
switch (format[f])
{
case 'm':
case 'M':
if (! parseDigits(i, month, 2, format[f] == 'M'))
return false;
break;
case 'd':
case 'D':
if (! parseDigits(i, day, 2, format[f] == 'D'))
return false;
break;
case 'y':
case 'Y':
if (! parseDigits(i, year, format[f] == 'y' ? 2 : 4))
return false;
if (format[f] == 'y')
year += 2000;
break;
case 'h':
case 'H':
if (! parseDigits(i, hour, 2, format[f] == 'H'))
return false;
break;
case 'n':
case 'N':
if (! parseDigits(i, minute, 2, format[f] == 'N'))
return false;
break;
case 's':
case 'S':
if (! parseDigits(i, second, 2, format[f] == 'S'))
return false;
break;
// Merely parse, not extract.
case 'v':
case 'V':
if (! parseDigits(i, week, 2, format[f] == 'V'))
return false;
break;
// Merely parse, not extract.
case 'a':
case 'A':
if (i + 3 <= _length &&
! Lexer::isDigit ((*_input)[i + 0]) &&
! Lexer::isDigit ((*_input)[i + 1]) &&
! Lexer::isDigit ((*_input)[i + 2]))
{
wday = ISO8601d::dayOfWeek (_input->substr (i, 3).c_str ());
i += (format[f] == 'a') ? 3 : ISO8601d::dayName (wday).size ();
}
else
return false;
break;
case 'b':
case 'B':
if (i + 3 <= _length &&
! Lexer::isDigit ((*_input)[i + 0]) &&
! Lexer::isDigit ((*_input)[i + 1]) &&
! Lexer::isDigit ((*_input)[i + 2]))
{
if (month != -1)
return false;
month = ISO8601d::monthOfYear (_input->substr (i, 3).c_str());
i += (format[f] == 'b') ? 3 : ISO8601d::monthName (month).size ();
}
else
return false;
break;
default:
if (i + 1 <= _length &&
(*_input)[i] == format[f])
++i;
else
return false;
break;
}
}
// By default, the most global date variables that are undefined are put to
// the current date (for instance, the year to the current year for formats
// that lack Y/y). If even 'second' is undefined, then the date is parsed as
// now.
if (year == -1)
{
ISO8601d now;
year = now.year ();
if (month == -1)
{
month = now.month ();
if (day == -1)
{
day = now.day ();
if (hour == -1)
{
hour = now.hour ();
if (minute == -1)
{
minute = now.minute ();
if (second == -1)
second = now.second ();
}
}
}
}
}
// Put all remaining undefined date variables to their default values (0 or
// 1).
month = (month == -1) ? 1 : month;
day = (day == -1) ? 1 : day;
hour = (hour == -1) ? 0 : hour;
minute = (minute == -1) ? 0 : minute;
second = (second == -1) ? 0 : second;
// Check that values are correct
if (! ISO8601d::valid (month, day, year, hour, minute, second))
return false;
// Convert to epoch.
struct tm tms {};
tms.tm_isdst = -1; // Requests that mktime determine summer time effect.
tms.tm_mon = month - 1;
tms.tm_mday = day;
tms.tm_year = year - 1900;
tms.tm_hour = hour;
tms.tm_min = minute;
tms.tm_sec = second;
t = mktime (&tms);
_cursor = i;
return true;
}
