import datetime
from itertools import combinations
from typing import Set, Tuple

from money.currency import Currency

from xexe.currency_pair import CurrencyPair


class DateRange:

    def __init__(self, start_date: datetime.date, end_date: datetime.date):
        if type(start_date) != datetime.date or type(end_date) != datetime.date:
            raise TypeError("start_date and end_date must be date objects.")

        if start_date > end_date:
            raise ValueError("start_date can't be after end_date.")

        self._start_date = start_date
        self._end_date = end_date

    @property
    def start_date(self):
        return self._start_date

    @start_date.setter
    def start_date(self, value: datetime.date):
        if type(value) != datetime.date:
            raise TypeError("start_date must be a date object.")

        if value > self._end_date:
            raise ValueError("start_date can't be after end_date.")

        self._start_date = value

    @property
    def end_date(self):
        return self._end_date

    @end_date.setter
    def end_date(self, value: datetime.date):
        if type(value) != datetime.date:
            raise TypeError("end_date must be a date object.")

        if value < self._start_date:
            raise ValueError("end_date can't be before start_date.")

        self._end_date = value

    def __eq__(self, other: "DateRange") -> bool:
        if not isinstance(other, DateRange):
            raise TypeError("DataRange can only be compared to other DateRange.")

        start_dates_are_different = self.start_date != other.start_date
        end_dates_are_different = self.end_date != other.end_date

        if start_dates_are_different or end_dates_are_different:
            return False

        return True

    def __repr__(self) -> str:
        return f"""Date Range: {self.start_date.strftime("%Y-%m-%d")} to {self.end_date.strftime("%Y-%m-%d")}."""

    def __iter__(self):
        current_date = self.start_date
        while current_date <= self.end_date:
            yield current_date
            current_date += datetime.timedelta(days=1)


def generate_pairs_and_dates_combinations(
    date_range: DateRange, pairs: Set[CurrencyPair]
) -> Tuple[dict]:
    currency_date_combinations = []
    for date in date_range:
        for pair in pairs:
            currency_date_combinations.append(
                {
                    "from_currency": pair.from_currency,
                    "to_currency": pair.to_currency,
                    "date": date,
                }
            )

    currency_date_combinations = tuple(currency_date_combinations)

    return currency_date_combinations