1  # SPDX-License-Identifier: MIT
       2  # SPDX-FileCopyrightText: 2021 Taneli Hukkinen
       3  # Licensed to PSF under a Contributor Agreement.
       4  
       5  from __future__ import annotations
       6  
       7  from datetime import date, datetime, time, timedelta, timezone, tzinfo
       8  from functools import lru_cache
       9  import re
      10  from typing import Any
      11  
      12  from ._types import ParseFloat
      13  
      14  # E.g.
      15  # - 00:32:00.999999
      16  # - 00:32:00
      17  _TIME_RE_STR = r"([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9])(?:\.([0-9]{1,6})[0-9]*)?"
      18  
      19  RE_NUMBER = re.compile(
      20      r"""
      21  0
      22  (?:
      23      x[0-9A-Fa-f](?:_?[0-9A-Fa-f])*   # hex
      24      |
      25      b[01](?:_?[01])*                 # bin
      26      |
      27      o[0-7](?:_?[0-7])*               # oct
      28  )
      29  |
      30  [+-]?(?:0|[1-9](?:_?[0-9])*)         # dec, integer part
      31  (?P<floatpart>
      32      (?:\.[0-9](?:_?[0-9])*)?         # optional fractional part
      33      (?:[eE][+-]?[0-9](?:_?[0-9])*)?  # optional exponent part
      34  )
      35  """,
      36      flags=re.VERBOSE,
      37  )
      38  RE_LOCALTIME = re.compile(_TIME_RE_STR)
      39  RE_DATETIME = re.compile(
      40      rf"""
      41  ([0-9]{{4}})-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])  # date, e.g. 1988-10-27
      42  (?:
      43      [Tt ]
      44      {_TIME_RE_STR}
      45      (?:([Zz])|([+-])([01][0-9]|2[0-3]):([0-5][0-9]))?  # optional time offset
      46  )?
      47  """,
      48      flags=re.VERBOSE,
      49  )
      50  
      51  
      52  def match_to_datetime(match: re.Match) -> datetime | date:
      53      """Convert a `RE_DATETIME` match to `datetime.datetime` or `datetime.date`.
      54  
      55      Raises ValueError if the match does not correspond to a valid date
      56      or datetime.
      57      """
      58      (
      59          year_str,
      60          month_str,
      61          day_str,
      62          hour_str,
      63          minute_str,
      64          sec_str,
      65          micros_str,
      66          zulu_time,
      67          offset_sign_str,
      68          offset_hour_str,
      69          offset_minute_str,
      70      ) = match.groups()
      71      year, month, day = int(year_str), int(month_str), int(day_str)
      72      if hour_str is None:
      73          return date(year, month, day)
      74      hour, minute, sec = int(hour_str), int(minute_str), int(sec_str)
      75      micros = int(micros_str.ljust(6, "0")) if micros_str else 0
      76      if offset_sign_str:
      77          tz: tzinfo | None = cached_tz(
      78              offset_hour_str, offset_minute_str, offset_sign_str
      79          )
      80      elif zulu_time:
      81          tz = timezone.utc
      82      else:  # local date-time
      83          tz = None
      84      return datetime(year, month, day, hour, minute, sec, micros, tzinfo=tz)
      85  
      86  
      87  @lru_cache(maxsize=None)
      88  def cached_tz(hour_str: str, minute_str: str, sign_str: str) -> timezone:
      89      sign = 1 if sign_str == "+" else -1
      90      return timezone(
      91          timedelta(
      92              hours=sign * int(hour_str),
      93              minutes=sign * int(minute_str),
      94          )
      95      )
      96  
      97  
      98  def match_to_localtime(match: re.Match) -> time:
      99      hour_str, minute_str, sec_str, micros_str = match.groups()
     100      micros = int(micros_str.ljust(6, "0")) if micros_str else 0
     101      return time(int(hour_str), int(minute_str), int(sec_str), micros)
     102  
     103  
     104  def match_to_number(match: re.Match, parse_float: ParseFloat) -> Any:
     105      if match.group("floatpart"):
     106          return parse_float(match.group())
     107      return int(match.group(), 0)