from django.template import Library
from datetime import datetime, timedelta

@register.filter
def is_day_of(value,arg):
    return (arg and value) and arg.day == int(value)

@register.filter
def is_month_of(value,arg):
    return (arg and value) and arg.month == int(value)

@register.filter
def is_year_of(value,arg):
    return (arg and value) and arg.year == int(value)

@register.filter
def is_hour_of(value,arg):
    return (arg and value) and arg.hour == int(value)

@register.filter
def is_minute_of(value,arg):
    return (arg and value) and arg.minute == int(value)

@register.filter
def dec_year(value,arg):
    delta = type(arg) != types.IntType and int(arg) or arg
    return value - timedelta(365 * delta)

@register.filter
def dec_month(value,arg):
    delta = type(arg) != types.IntType and int(arg) or arg
    return value - timedelta(30 * delta)

@register.filter
def inc_year(value,arg):
    delta = type(arg) != types.IntType and int(arg) or arg
    return value + timedelta(365 * delta)

@register.filter
def inc_month(value,arg):
    delta = type(arg) != types.IntType and int(arg) or arg
    return value + timedelta(30 * delta)