from pathlib import Path

import pytest

from engine.character import Character
from engine.defs import DefRegistry
from engine.entity import EntityPosition
from engine.map import Map
from engine.tile import Tile, TileLayerInstance
from engine.world import World
from resources.logic.actions import activate_implant

DEFS_DIR = Path(__file__).resolve().parent.parent / "resources" / "defs"


@pytest.fixture()
def registry():
    return DefRegistry.load(DEFS_DIR)


def make_human(registry, **kwargs) -> Character:
    return Character(species_id="human", default_body_parts=registry.new_default_body_parts("human"), **kwargs)


def make_world(registry):
    field = Map("field", 15, 15, 1)
    for x in range(15):
        for y in range(15):
            field.set_tile(x, y, 0, Tile(flooring=TileLayerInstance("grass")))
    world = World(registry=registry)
    world.add_map(field)
    return world


# --- install/uninstall -----------------------------------------------------------------------


def test_install_implant_adds_to_character(registry):
    character = make_human(registry)
    assert character.install_implant("chronoimplant", registry) is True
    assert "chronoimplant" in character.implants


def test_install_implant_rejects_non_implant_item(registry):
    character = make_human(registry)
    assert character.install_implant("chronowand", registry) is False
    assert character.implants == []


def test_install_implant_rejects_duplicate(registry):
    character = make_human(registry)
    character.install_implant("chronoimplant", registry)
    assert character.install_implant("chronoimplant", registry) is False
    assert character.implants == ["chronoimplant"]


def test_uninstall_implant_removes_it(registry):
    character = make_human(registry)
    character.install_implant("chronoimplant", registry)
    character.uninstall_implant("chronoimplant")
    assert character.implants == []


def test_uninstall_implant_no_op_if_not_installed(registry):
    character = make_human(registry)
    character.uninstall_implant("chronoimplant")  # should not raise
    assert character.implants == []


# --- activate_implant -------------------------------------------------------------------------


def test_activate_implant_casts_time_warp_sphere(registry):
    world = make_world(registry)
    caster = make_human(registry, position=EntityPosition("field", 5.0, 5.0, 0.0))
    caster.install_implant("chronoimplant", registry)
    world.add_entity(caster)

    assert world.time_warp_zones == []
    result = activate_implant(caster, world, registry, "chronoimplant", now=3.0)
    assert len(world.time_warp_zones) == 1
    assert result is world.time_warp_zones[0]
    assert result.expires_at > 3.0


def test_activate_implant_returns_none_if_not_installed(registry):
    world = make_world(registry)
    caster = make_human(registry, position=EntityPosition("field", 5.0, 5.0, 0.0))
    world.add_entity(caster)

    result = activate_implant(caster, world, registry, "chronoimplant", now=3.0)
    assert result is None
    assert world.time_warp_zones == []


def test_activate_implant_returns_none_for_non_ability_implant(registry):
    world = make_world(registry)
    caster = make_human(registry, position=EntityPosition("field", 5.0, 5.0, 0.0))
    caster.install_implant("chronoimplant", registry)
    world.add_entity(caster)
    # a hypothetical implant with no grants_ability should be a safe no-op, not a crash
    object.__setattr__(registry.get_item_def("chronoimplant"), "grants_ability", None)

    result = activate_implant(caster, world, registry, "chronoimplant", now=3.0)
    assert result is None