from dataclasses import dataclass

from common.utils import compute_hash
from core.BuiltinConcepts import BuiltinConcepts
from core.ExecutionContext import ExecutionContext


class SheerkaException(Exception):
    def get_error_msg(self) -> str:
        pass


class MethodAccessError(SheerkaException):
    def __init__(self, method_name):
        self.method_name = method_name

    def get_error_msg(self) -> str:
        return f"Cannot access method '{self.method_name}'"


class NotEnoughParameters(SheerkaException):
    """
    Exception when not enough parameters are found during Sya parsing
    """

    def __init__(self, concept_to_recognize, expected_nb_parameters, nb_parameters_found):
        self.concept = concept_to_recognize
        self.expected = expected_nb_parameters
        self.found = nb_parameters_found

    def get_error_msg(self) -> str:
        return f"Failed to parse {self.concept}. Expecting {self.expected} parameters, but only found {self.found}."


@dataclass
class ErrorObj:
    def get_error_msg(self) -> str:
        pass


class ErrorContext(ErrorObj):
    """
    This class represents the result of a data flow processing
    """

    def __init__(self, who: str, context: ExecutionContext, value: object = None):
        self.who = who
        self.context = context
        self.value = value
        self.parents = None

    def __repr__(self):
        return f"Error(who={self.who}, context_id={self.context.medium_id}, value={self.value})"

    def __eq__(self, other):
        if id(self) == id(other):
            return True

        if not isinstance(other, ErrorContext):
            return False

        return self.who == other.who and \
            self.context.id == other.context.id and \
            self.value == other.value

    def __hash__(self):
        return hash((self.who, self.context.id, compute_hash(self.value)))

    def get_error_msg(self):
        value_as_list = self.value if isinstance(self.value, list) else [self.value]
        temp = []
        for value in value_as_list:
            if isinstance(value, str):
                temp.append(value)
            elif isinstance(value, (SheerkaException, ErrorObj)):
                temp.append(value.get_error_msg())
            else:
                temp.append(repr(value))

        return ", ".join(temp)


ErrorConcepts = {BuiltinConcepts.UNKNOWN_CONCEPT,
                 BuiltinConcepts.EVALUATION_ERROR,
                 BuiltinConcepts.INVALID_CONCEPT}