"""Collection of common components."""

from __future__ import annotations

from typing import Final, Self

import attrs

import tcod.ecs.callbacks

from tcod.ecs import Entity

@attrs.define(frozen=True)

class Position:

"""An entities position."""

x: int

y: int

def __add__(self, direction: tuple[int, int]) -> Self:

"""Add a vector to this position."""

x, y = direction

return self.__class__(self.x + x, self.y + y)

@tcod.ecs.callbacks.register_component_changed(component=Position)

def on_position_changed(entity: Entity, old: Position | None, new: Position | None) -> None:

"""Mirror position components as a tag."""

if old == new:

return

if old is not None:

entity.tags.discard(old)

if new is not None:

entity.tags.add(new)

@attrs.define(frozen=True)

class Graphic:

"""An entities icon and color."""

ch: int = ord("!")

fg: tuple[int, int, int] = (255, 255, 255)

Gold: Final = ("Gold", int)

"""Amount of gold."""