# -*- coding: utf-8 -*-
"""WebKit time implementation."""
import decimal
from dfdatetime import definitions
from dfdatetime import factory
from dfdatetime import interface
[docs]
class WebKitTimeEpoch(interface.DateTimeEpoch):
"""WebKit time epoch."""
[docs]
def __init__(self):
"""Initializes a WebKit time epoch."""
super(WebKitTimeEpoch, self).__init__(1601, 1, 1)
[docs]
class WebKitTime(interface.DateTimeValues):
"""WebKit timestamp.
The WebKit timestamp is a signed 64-bit integer that contains the number of
microseconds since 1601-01-01 00:00:00.
Attributes:
is_local_time (bool): True if the date and time value is in local time.
"""
_EPOCH = WebKitTimeEpoch()
# The difference between January 1, 1601 and January 1, 1970 in seconds.
_WEBKIT_TO_POSIX_BASE = 11644473600
[docs]
def __init__(self, precision=None, time_zone_offset=None, timestamp=None):
"""Initializes a WebKit timestamp.
Args:
precision (Optional[str]): precision of the date and time value, which
should be one of the PRECISION_VALUES in definitions.
time_zone_offset (Optional[int]): time zone offset in number of minutes
from UTC or None if not set.
timestamp (Optional[int]): WebKit timestamp.
"""
super(WebKitTime, self).__init__(
precision=precision or definitions.PRECISION_1_MICROSECOND,
time_zone_offset=time_zone_offset)
self._timestamp = timestamp
@property
def timestamp(self):
"""decimal.Decimal: WebKit timestamp or None if not set."""
return self._timestamp
def _GetNormalizedTimestamp(self):
"""Retrieves the normalized timestamp.
Returns:
float: normalized timestamp, which contains the number of seconds since
January 1, 1970 00:00:00 and a fraction of second used for increased
precision, or None if the normalized timestamp cannot be determined.
"""
if self._normalized_timestamp is None:
if (self._timestamp is not None and self._timestamp >= self._INT64_MIN and
self._timestamp <= self._INT64_MAX):
self._normalized_timestamp = (
decimal.Decimal(self._timestamp) /
definitions.MICROSECONDS_PER_SECOND)
self._normalized_timestamp -= self._WEBKIT_TO_POSIX_BASE
if self._time_zone_offset:
self._normalized_timestamp -= self._time_zone_offset * 60
return self._normalized_timestamp
[docs]
def CopyFromDateTimeString(self, time_string):
"""Copies a WebKit timestamp from a date and time string.
Args:
time_string (str): date and time value formatted as:
YYYY-MM-DD hh:mm:ss.######[+-]##:##
Where # are numeric digits ranging from 0 to 9 and the seconds
fraction can be either 3, 6 or 9 digits. The time of day, seconds
fraction and time zone offset are optional. The default time zone
is UTC.
Raises:
ValueError: if the time string is invalid or not supported.
"""
date_time_values = self._CopyDateTimeFromString(time_string)
year = date_time_values.get('year', 0)
month = date_time_values.get('month', 0)
day_of_month = date_time_values.get('day_of_month', 0)
hours = date_time_values.get('hours', 0)
minutes = date_time_values.get('minutes', 0)
seconds = date_time_values.get('seconds', 0)
nanoseconds = date_time_values.get('nanoseconds', 0)
time_zone_offset = date_time_values.get('time_zone_offset', None)
microseconds, _ = divmod(
nanoseconds, definitions.NANOSECONDS_PER_MICROSECOND)
timestamp = self._GetNumberOfSecondsFromElements(
year, month, day_of_month, hours, minutes, seconds)
timestamp += self._WEBKIT_TO_POSIX_BASE
timestamp *= definitions.MICROSECONDS_PER_SECOND
timestamp += microseconds
self._normalized_timestamp = None
self._timestamp = timestamp
self._time_zone_offset = time_zone_offset
[docs]
def CopyToDateTimeString(self):
"""Copies the WebKit timestamp to a date and time string.
Returns:
str: date and time value formatted as: "YYYY-MM-DD hh:mm:ss.######" or
None if the timestamp is missing or invalid.
"""
if (self._timestamp is None or self._timestamp < self._INT64_MIN or
self._timestamp > self._INT64_MAX):
return None
timestamp, microseconds = divmod(
self._timestamp, definitions.MICROSECONDS_PER_SECOND)
number_of_days, hours, minutes, seconds = self._GetTimeValues(timestamp)
year, month, day_of_month = self._GetDateValuesWithEpoch(
number_of_days, self._EPOCH)
return (f'{year:04d}-{month:02d}-{day_of_month:02d} '
f'{hours:02d}:{minutes:02d}:{seconds:02d}.{microseconds:06d}')
factory.Factory.RegisterDateTimeValues(WebKitTime)