import datetime
import logging
import pathlib
from typing import Union

from money.currency import Currency

from xexe.constants import DEFAULT_CURRENCIES, RATES_SOURCES
from xexe.currency_pair import CurrencyPair
from xexe.utils import DateRange

logger = logging.getLogger()


def handle_get_rates_inputs(
    start_date: Union[datetime.datetime, datetime.date],
    end_date: Union[datetime.datetime, datetime.date],
    dry_run: bool,
    rates_source: str,
    ignore_warnings: bool,
    output: Union[str, pathlib.Path],
    currencies: Union[None, str] = None,
    pairs: Union[None, str] = None,
):
    logger.info("Handling inputs.")

    date_range = DateRange(start_date=start_date.date(), end_date=end_date.date())

    if date_range.end_date > datetime.datetime.today().date():
        date_range.end_date = datetime.datetime.today().date()

    if pairs:
        if currencies:
            logger.error(f"Received both currencies and pairs.")
            logger.error(f"Currencies: '{currencies}'.")
            logger.error(f"Pairs: '{pairs}'.")
            raise ValueError("You can pass currencies or pairs, but not both.")

        pairs = {
            CurrencyPair(
                from_currency=Currency[str_pair[0:3]],
                to_currency=Currency[str_pair[3:6]],
            )
            for str_pair in pairs.split(",")
        }

    if currencies:
        # CLI input comes as a string of comma-separated currency codes
        currencies = {currency_code.strip() for currency_code in currencies.split(",")}
        tmp = {Currency(currency_code) for currency_code in currencies}
        currencies = tmp

    if currencies is None or currencies == "" and not pairs:
        logger.info("No currency list or pairs passed. Running for default currencies.")
        currencies = DEFAULT_CURRENCIES

    if rates_source not in RATES_SOURCES:
        raise ValueError(f"--rates-source must be one of {RATES_SOURCES.keys()}.")

    if not output == "dwh":
        # The Path constructor is idempotent, so this works equally fine if output
        # is a string or an actual Path object.
        output = pathlib.Path(output)
        if output.suffix != ".csv":
            raise ValueError("File output must be a .csv file.")

    prepared_inputs = {
        "date_range": date_range,
        "dry_run": dry_run,
        "rates_source": rates_source,
        "ignore_warnings": ignore_warnings,
        "output": output,
    }

    if currencies:
        prepared_inputs["currencies"] = currencies

    if pairs:
        prepared_inputs["pairs"] = pairs

    logger.debug(prepared_inputs)
    return prepared_inputs