from datetime import datetime
from typing import Any, Iterable, Optional

import flag

from apollo_notifications.constants import APOLLO_GLOBAL_MARKET, DATETIME_FORMAT, GLOBAL_MARKET


def get_country_code(country_code: str or None) -> str:
    """Prepare country code for using in queries."""

    if not country_code:
        return ''

    _country_code = country_code.lower()
    if _country_code == GLOBAL_MARKET:
        return APOLLO_GLOBAL_MARKET

    return _country_code


def get_country_flag(country_code: str or None) -> str:
    """Returns flag symbol by country_code"""

    if not country_code:
        return ''
    return '🌍' if country_code == APOLLO_GLOBAL_MARKET else flag.flag(country_code)


def filter_by(result: Iterable[Any], by: Optional[Iterable[Any]]) -> Iterable[Any]:
    """Filter some collection by passed values."""

    if filter_by:
        result = list(set(result) & set(by))
    return result


def parse_global_to_gl(market: Optional[str]) -> Optional[str]:
    if not market:
        return
    if market == GLOBAL_MARKET:
        return APOLLO_GLOBAL_MARKET
    return market.lower()


def parse_gl_to_global(market: Optional[str]) -> Optional[str]:
    if not market:
        return
    if market == APOLLO_GLOBAL_MARKET:
        return GLOBAL_MARKET
    return market.lower()


def load_datetime(dt_str: Optional[str], format=DATETIME_FORMAT) -> Optional[datetime]:
    if dt_str:
        return datetime.strptime(dt_str, format)


def dump_datetime(dt: datetime, format=DATETIME_FORMAT) -> Optional[str]:
    if datetime:
        return dt.strftime(format)