"""Provides "fake" formulas."""

from abc import ABC
from typing import Any, Tuple
from functools import cache

from public import public

from pyecsca.ec.formula.base import (
    AdditionFormula,
    FormulaAction,
    Formula,
    DoublingFormula,
    TriplingFormula,
    LadderFormula,
    NegationFormula,
    ScalingFormula,
    DifferentialAdditionFormula,
)
from pyecsca.ec.mod import Mod, Undefined
from pyecsca.ec.point import Point


@public
class FakeFormula(Formula, ABC):
    """
    No matter what the input point is, it just returns the right amount of FakePoints.

    Useful for computing with the scalar multipliers without having concrete formulas
    and points (for example, to get the addition chain via the :py:class:`~.MultipleContext`).
    """

    def __init__(self, coordinate_model):
        # TODO: This is missing all of the other attributes
        self.coordinate_model = coordinate_model
        self.code = []

    def __call__(self, field: int, *points: Any, **params: Mod) -> Tuple[Any, ...]:
        with FormulaAction(self, *points, **params) as action:
            for i in range(self.num_outputs):
                res = FakePoint(self.coordinate_model)
                action.output_points.append(res)
            return action.exit(tuple(action.output_points))


@public
class FakeAdditionFormula(FakeFormula, AdditionFormula):
    name = "fake"


@public
class FakeDoublingFormula(FakeFormula, DoublingFormula):
    name = "fake"


@public
class FakeTriplingFormula(FakeFormula, TriplingFormula):
    name = "fake"


@public
class FakeNegationFormula(FakeFormula, NegationFormula):
    name = "fake"


@public
class FakeScalingFormula(FakeFormula, ScalingFormula):
    name = "fake"


@public
class FakeDifferentialAdditionFormula(FakeFormula, DifferentialAdditionFormula):
    name = "fake"


@public
class FakeLadderFormula(FakeFormula, LadderFormula):
    name = "fake"


@cache
def _fake_coords(model):
    """Return a dictionary of fake coordinates for the given model."""
    return {key: Undefined() for key in model.variables}


@public
class FakePoint(Point):
    """Just a fake point."""

    def __init__(self, model):  # noqa: We initialize everything here
        self.coordinate_model = model

    @property
    def field(self):
        return 0

    @field.setter
    def field(self, value):
        """Setter for field, does nothing."""
        pass

    @property
    def coords(self):
        return _fake_coords(self.coordinate_model)

    @coords.setter
    def coords(self, value):
        """Setter for coordinates, does nothing."""
        pass

    def __str__(self):
        return f"FakePoint{id(self)}"

    def __repr__(self):
        return str(self)

    def __eq__(self, other):
        return self is other

    def __hash__(self):
        return id(self)

    def __copy__(self):
        return self

    def __deepcopy__(self, memo):
        return self

    def __getstate__(self):
        return {"model": self.coordinate_model}

    def __setstate__(self, state):
        self.coordinate_model = state["model"]