"""Feed Status Monitor utils."""

import collections
import datetime
from datetime import date, timedelta

from dateutil.relativedelta import relativedelta

from feed_status import config

EMPTY_VALUE = '--'
ONE_DAY = datetime.timedelta(days=1)


def generate_default_date_dict_range(
        from_date: datetime.date, to_date: datetime.date):
    """Generate default date dict range."""
    assert from_date < to_date
    current_date = to_date
    default_days = collections.OrderedDict()
    while current_date > from_date:
        default_days[str(current_date)] = EMPTY_VALUE
        current_date -= ONE_DAY

    return default_days


def generate_default_month_date_dict_range(
    from_date: datetime.date,
    to_date: datetime.date,
):
    """Generate default date dict range."""
    assert from_date < to_date
    first_month = from_date.replace(day=1)
    end_month = to_date.replace(day=1)
    delta = relativedelta(end_month, first_month)
    return collections.OrderedDict(
        {
            str(end_month - relativedelta(months=m)): EMPTY_VALUE
            for m in range(delta.years*12+delta.months)
        }
    )


def get_start_date():
    """Return stating date of feed_statuses displayed on dashboard."""
    return str(date.today() - timedelta(days=config.DASHBOARD_DISPLAYED_DAYS))


def set_date_range_for_feeds(ingestion_feeds, dates):
    """Produce the same date range for all feeds."""
    for feed in ingestion_feeds:
        for dt in dates - set(feed.status.keys()):
            feed.status[dt] = EMPTY_VALUE
        feed.status = collections.OrderedDict(
            sorted(
                feed.status.items(),
                reverse=True,
            )
        )
    return ingestion_feeds