import abc
from typing import Union

from mfg_package.environment import rewards as r, constants as c
from mfg_package.utils.helpers import MOVEMAP
from mfg_package.utils.results import ActionResult


class Action(abc.ABC):

    @property
    def name(self):
        return self._identifier

    @abc.abstractmethod
    def __init__(self, identifier: str):
        self._identifier = identifier

    @abc.abstractmethod
    def do(self, entity, state) -> Union[None, ActionResult]:
        return

    def __repr__(self):
        return f'Action[{self._identifier}]'


class Noop(Action):

    def __init__(self):
        super().__init__(c.NOOP)

    def do(self, entity, *_) -> Union[None, ActionResult]:
        return ActionResult(identifier=self._identifier, validity=c.VALID,
                            reward=r.NOOP, entity=entity)


class Move(Action, abc.ABC):

    @abc.abstractmethod
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

    def do(self, entity, env):
        new_pos = self._calc_new_pos(entity.pos)
        if next_tile := env[c.FLOOR].by_pos(new_pos):
            # noinspection PyUnresolvedReferences
            valid = entity.move(next_tile)
        else:
            valid = c.NOT_VALID
        reward = r.MOVEMENTS_VALID if valid else r.MOVEMENTS_FAIL
        return ActionResult(entity=entity, identifier=self._identifier, validity=valid, reward=reward)

    def _calc_new_pos(self, pos):
        x_diff, y_diff = MOVEMAP[self._identifier]
        return pos[0] + x_diff, pos[1] + y_diff


class North(Move):
    def __init__(self, *args, **kwargs):
        super().__init__(c.NORTH, *args, **kwargs)


class NorthEast(Move):
    def __init__(self, *args, **kwargs):
        super().__init__(c.NORTHEAST, *args, **kwargs)


class East(Move):
    def __init__(self, *args, **kwargs):
        super().__init__(c.EAST, *args, **kwargs)


class SouthEast(Move):
    def __init__(self, *args, **kwargs):
        super().__init__(c.SOUTHEAST, *args, **kwargs)


class South(Move):
    def __init__(self, *args, **kwargs):
        super().__init__(c.SOUTH, *args, **kwargs)


class SouthWest(Move):
    def __init__(self, *args, **kwargs):
        super().__init__(c.SOUTHWEST, *args, **kwargs)


class West(Move):
    def __init__(self, *args, **kwargs):
        super().__init__(c.WEST, *args, **kwargs)


class NorthWest(Move):
    def __init__(self, *args, **kwargs):
        super().__init__(c.NORTHWEST, *args, **kwargs)


Move4 = [North, East, South, West]
# noinspection PyTypeChecker
Move8 = Move4 + [NorthEast, SouthEast, SouthWest, NorthWest]
