1 files changed, 85 insertions, 0 deletions
diff --git a/diplomacy/utils/time.py b/diplomacy/utils/time.py
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+++ b/diplomacy/utils/time.py
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+# ==============================================================================
+# Copyright (C) 2019 - Philip Paquette
+#
+#  This program is free software: you can redistribute it and/or modify it under
+#  the terms of the GNU Affero General Public License as published by the Free
+#  Software Foundation, either version 3 of the License, or (at your option) any
+#  later version.
+#
+#  This program is distributed in the hope that it will be useful, but WITHOUT
+#  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+#  FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
+#  details.
+#
+#  You should have received a copy of the GNU Affero General Public License along
+#  with this program.  If not, see <https://www.gnu.org/licenses/>.
+# ==============================================================================
+""" Time functions
+    - Contains generic time functions (e.g. to calculate deadlines)
+"""
+import calendar
+import datetime
+import math
+import pytz
+
+def str_to_seconds(offset_str):
+    """ Converts a time in format 00W00D00H00M00S in number of seconds
+        :param offset_str: The string to convert (e.g. '20D')
+        :return: Its equivalent in seconds = 1728000
+    """
+    mult = {'W': 7 * 24 * 60 * 60, 'D': 24 * 60 * 60, 'H': 60 * 60, 'M': 60, 'S': 1, ' ': 1}
+    buffer = current_sum = 0
+    offset_str = str(offset_str)
+
+    # Adding digits to buffer, when a character is found,
+    # multiply it with buffer and increase the current_sum
+    for char in offset_str:
+        if char.isdigit():
+            buffer = buffer * 10 + int(char)
+        elif char.upper() in mult:
+            current_sum += buffer * mult[char.upper()]
+            buffer = 0
+        else:
+            buffer = 0
+    current_sum += buffer
+
+    return current_sum
+
+def trunc_time(timestamp, trunc_interval, time_zone='GMT'):
+    """  Truncates time at a specific interval (e.g. 20M) (i.e. Rounds to the next :20, :40, :60)
+        :param timestamp: The unix epoch to truncate (e.g. 1498746120)
+        :param trunc_interval: The truncation interval (e.g. 60*60 or '1H')
+        :param time_zone: The time to use for conversion (defaults to GMT otherwise)
+        :return: A timestamp truncated to the nearest (future) interval
+    """
+    midnight_ts = calendar.timegm(datetime.datetime.combine(datetime.date.today(), datetime.time.min).utctimetuple())
+    midnight_offset = (timestamp - midnight_ts) % (24*3600)
+
+    dtime = datetime.datetime.fromtimestamp(timestamp, pytz.timezone(time_zone))
+    tz_offset = dtime.utcoffset().total_seconds()
+    interval = str_to_seconds(trunc_interval)
+    trunc_offset = math.ceil((midnight_offset + tz_offset) / interval) * interval
+
+    trunc_ts = timestamp - midnight_offset + trunc_offset - tz_offset
+    return int(trunc_ts)
+
+def next_time_at(timestamp, time_at, time_zone='GMT'):
+    """ Returns the next timestamp at a specific 'hh:mm'
+        :param timestamp: The unix timestamp to convert
+        :param time_at: The next 'hh:mm' to have the time rounded to, or 0 to skip
+        :param time_zone: The time to use for conversion (defaults to GMT otherwise)
+        :return: A timestamp truncated to the nearest (future) hh:mm
+    """
+    if not time_at:
+        return timestamp
+
+    midnight_ts = calendar.timegm(datetime.datetime.combine(datetime.date.today(), datetime.time.min).utctimetuple())
+    midnight_offset = (timestamp - midnight_ts) % (24*3600)
+
+    dtime = datetime.datetime.fromtimestamp(timestamp, pytz.timezone(time_zone))
+    tz_offset = dtime.utcoffset().total_seconds()
+    trunc_interval = '%dH%dM' % (int(time_at.split(':')[0]), int(time_at.split(':')[1])) if ':' in time_at else time_at
+    interval = str_to_seconds(trunc_interval)
+    at_offset = (-midnight_offset + interval - tz_offset) % (24 * 3600)
+    at_ts = timestamp + at_offset
+    return int(at_ts)