from __future__ import annotations

from typing import TYPE_CHECKING, Final

from delta_barth.constants import DEFAULT_API_ERR_CODE, DEFAULT_INTERNAL_ERR_CODE
from delta_barth.types import DataPipeStates, Status

if TYPE_CHECKING:
    from delta_barth.types import DelBarApiError, ErrorDescription


class UnspecifiedRequestType(Exception):
    """exception raised if for a given API endpoint a not defined operation is requested"""


class UnknownApiErrorCode(Exception):
    """exception raised if for a given request a unknown error response code is transmitted"""


class ApiConnectionError(Exception):
    """exception raised if an established connection is needed, but the current session is not connected"""


class FeaturesMissingError(Exception):
    """exception raised if needed features are missing"""


## ** internal error handling
DATA_PIPELINE_STATUS_DESCR: Final[tuple[ErrorDescription, ...]] = (
    ("SUCCESS", 0, "Erfolg"),
    ("TOO_FEW_POINTS", 1, "Datensatz besitzt nicht genügend Datenpunkte"),
    ("BAD_QUALITY", 2, "Prognosequalität des Modells unzureichend"),
)


class ErrorHandler:
    def __init__(self) -> None:
        self._pipe_states: DataPipeStates | None = None
        self._parse_data_pipe_states()

    @property
    def pipe_states(self) -> DataPipeStates:
        assert self._pipe_states is not None, (
            "tried to access not parsed data pipeline errors"
        )
        return self._pipe_states

    def _parse_data_pipe_states(self) -> None:
        if self._pipe_states is not None:
            return
        parsed_errors: dict[str, Status] = {}
        for err in DATA_PIPELINE_STATUS_DESCR:
            parsed_errors[err[0]] = Status(status_code=err[1], description=err[2])

        self._pipe_states = DataPipeStates(**parsed_errors)

    def error(
        self,
        description: str,
        message: str = "",
        err_code: int = DEFAULT_INTERNAL_ERR_CODE,
    ) -> Status:
        return Status(
            status_code=err_code,
            description=description,
            message=message,
        )

    def api_error(
        self,
        error: DelBarApiError,
    ) -> Status:
        description = "Es ist ein Fehler bei der Kommunikation mit dem API-Server aufgetreten"
        message = (
            "Bitte beachten Sie die zusätzliche Fehlerausgabe des Servers in dieser Antwort"
        )
        return Status(
            status_code=DEFAULT_API_ERR_CODE,
            description=description,
            message=message,
            api_server_error=error,
        )