forget-cancellare-vecchi-toot/lib/interval.py

78 lines
2.2 KiB
Python

from datetime import timedelta
from statistics import mean
SCALES = [
('minutes', timedelta(minutes=1)),
('hours', timedelta(hours=1)),
('days', timedelta(days=1)),
('weeks', timedelta(days=7)),
('months', timedelta(days=
# you, a fool: a month is 30 days
# me, wise:
mean((31,
mean((29 if year % 400 == 0
or (year % 100 != 0 and year % 4 == 0)
else 28
for year in range(400)))
,31,30,31,30,31,31,30,31,30,31))
)),
('years', timedelta(days=
# you, a fool: ok. a year is 365.25 days. happy?
# me, wise: absolutely not
mean((366 if year % 400 == 0
or (year % 100 != 0 and year % 4 == 0)
else 365
for year in range(400)))
)),
]
def decompose_interval(attrname):
scales = [scale[1] for scale in SCALES]
scales.reverse()
def decorator(cls):
scl_name = '{}_scale'.format(attrname)
sig_name = '{}_significand'.format(attrname)
@property
def scale(self):
if getattr(self, attrname) == timedelta(0):
return timedelta(minutes=1)
for m in scales:
if getattr(self, attrname) % m == timedelta(0):
return m
return timedelta(minutes=1)
@scale.setter
def scale(self, value):
if(type(value) != timedelta):
value = timedelta(seconds=float(value))
setattr(self, attrname, max(1, getattr(self, sig_name)) * value)
@property
def significand(self):
return int(getattr(self, attrname) / getattr(self, scl_name))
@significand.setter
def significand(self, value):
if type(value) == str and value.strip() == '':
value = 0
try:
value = int(value)
assert value >= 0
except (ValueError, AssertionError) as e:
raise ValueError("Incorrect time interval", e)
setattr(self, attrname, value * getattr(self, scl_name))
setattr(cls, scl_name, scale)
setattr(cls, sig_name, significand)
return cls
return decorator