#!/usr/bin/env python3

from collections import namedtuple, defaultdict
from datetime import datetime
from decimal import Decimal

from util import UTCTZ, KSTTZ


class ObjEntry(namedtuple('ModifiedEntry',
                          ('bucket',
                           'path',
                           'etags',
                           'modified',
                           ))
               ):

    def __new__(cls, *args, **kwargs):
        item = super(ObjEntry, cls).__new__(cls, *args, **kwargs)
        return item

    def params(self, bucket, path):
        if (self.bucket, self.path) != (bucket, path):
            return ()
        if self.etags is not None:
            yield ('IfNoneMatch', self.etags)
        if self.modified is not None:
            yield ('IfModifiedSince', self.modified)


class Cost(namedtuple('Cost',
                      ('amount',
                       'currency',
                       'service',
                       'type',
                       'start',
                       'end'
                       ))
           ):
    __slots__ = ()

    def __new__(cls, *args, **kwargs):
        argdict = defaultdict(lambda: None)
        argdict.update(**kwargs)
        parse_date = lambda item: datetime.strptime(item, '%Y-%m-%dT%H:%M:%SZ').replace(tzinfo=UTCTZ).astimezone(KSTTZ)
        args = (
            (Decimal(argdict['lineItem/BlendedCost']) if argdict['lineItem/BlendedCost'] else None),
            (argdict['lineItem/CurrencyCode'] if argdict['lineItem/CurrencyCode'] else None),
            (argdict['product/ProductName'] if argdict['product/ProductName'] else None),
            (argdict['lineItem/UsageType'] if argdict['lineItem/UsageType'] else None),
            (parse_date(argdict['lineItem/UsageStartDate']) if argdict['lineItem/UsageStartDate'] else None),
            (parse_date(argdict['lineItem/UsageEndDate']) if argdict['lineItem/UsageEndDate'] else None)
        )
        item = super(Cost, cls).__new__(cls, *args)
        return item

    @property
    def key(self):
        return CostSummery(self.currency, self.service, self.type)


class CostSubItem(namedtuple('CostSubItem',
                             ('currency',
                              'service',
                              ))
                  ):
    __slots__ = ()

    def __new__(cls, *args):
        item = super(CostSubItem, cls).__new__(cls, *args)
        return item


class CostSummery(namedtuple('CostSummery',
                             ('currency',
                              'service',
                              'type'
                              ))
                  ):
    __slots__ = ()

    def __new__(cls, *args):
        item = super(CostSummery, cls).__new__(cls, *args)
        return item

    @property
    def key(self):
        return CostSubItem(self.currency, self.service)