from pathlib import Path

import pytest

from engine.character import BodyPart, Character, ClothingPiece
from engine.defs import DefRegistry

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


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


def make_character(registry, species_id: str, **kwargs) -> Character:
    return Character(species_id=species_id, default_body_parts=registry.new_default_body_parts(species_id), **kwargs)


# --- arm_slot_count -----------------------------------------------------------------------


def test_arm_slot_count_for_two_armed_species(registry):
    human = make_character(registry, "human")
    assert human.arm_slot_count() == 2


def test_arm_slot_count_for_four_armed_species(registry):
    reptilian = make_character(registry, "reptilian_quad")
    assert reptilian.arm_slot_count() == 4


def test_arm_slot_count_for_armless_species(registry):
    dog = make_character(registry, "dog")
    assert dog.arm_slot_count() == 0


def test_arm_slot_count_ignores_a_missing_arm(registry):
    human = make_character(registry, "human")
    human.body_parts.append(BodyPart("left_arm", "human_left_arm", removed=True))
    assert human.arm_slot_count() == 1


# --- wear_item: bigger (more sleeves) fits smaller, not vice versa --------------------------


def test_two_armed_species_can_wear_a_four_armed_jacket(registry):
    human = make_character(registry, "human")
    assert human.wear_item("torso", "reptilian_jacket", registry) is True
    assert human.get_clothing("torso").item_def_id == "reptilian_jacket"


def test_four_armed_species_cannot_wear_a_two_armed_jacket(registry):
    reptilian = make_character(registry, "reptilian_quad")
    assert reptilian.wear_item("torso", "leather_jacket", registry) is False
    assert reptilian.get_clothing("torso") is None


def test_four_armed_species_can_wear_a_four_armed_jacket(registry):
    reptilian = make_character(registry, "reptilian_quad")
    assert reptilian.wear_item("torso", "reptilian_jacket", registry) is True


def test_two_armed_species_can_wear_a_two_armed_jacket(registry):
    human = make_character(registry, "human")
    assert human.wear_item("torso", "leather_jacket", registry) is True


def test_non_sleeved_item_ignores_arm_count_entirely(registry):
    # dog_saddlebag has no arm_slots_required set (0 = unconstrained) - arm count is
    # irrelevant for a non-sleeved item, regardless of body type
    dog = make_character(registry, "dog")
    assert dog.wear_item("back", "dog_saddlebag", registry) is True


# --- wear_item: body_type gate (a dog can't wear human clothes, full stop) -------------------


def test_dog_cannot_wear_a_human_jacket(registry):
    dog = make_character(registry, "dog")
    assert dog.wear_item("torso", "leather_jacket", registry) is False
    assert dog.get_clothing("torso") is None


def test_dog_cannot_wear_a_four_armed_jacket_either(registry):
    # arm count would technically fit (0 <= 4) but body_type ("quadruped" vs "biped") rejects
    # it outright - a completely different anatomy, not just a sleeve-count mismatch
    dog = make_character(registry, "dog")
    assert dog.wear_item("torso", "reptilian_jacket", registry) is False


def test_dog_cannot_wear_a_human_backpack(registry):
    dog = make_character(registry, "dog")
    assert dog.wear_item("back", "backpack_basic", registry) is False


def test_dog_can_wear_dog_equipment(registry):
    dog = make_character(registry, "dog")
    assert dog.wear_item("torso", "dog_harness", registry) is True
    assert dog.wear_item("back", "dog_saddlebag", registry) is True


def test_biped_species_cannot_wear_dog_equipment(registry):
    human = make_character(registry, "human")
    reptilian = make_character(registry, "reptilian_quad")
    assert human.wear_item("torso", "dog_harness", registry) is False
    assert reptilian.wear_item("back", "dog_saddlebag", registry) is False


def test_reptilian_and_zenari_share_biped_body_type_and_can_wear_each_others_jackets(registry):
    zenari = make_character(registry, "alien_tri")
    assert zenari.wear_item("torso", "reptilian_jacket", registry) is True  # both bipeds, fits (2 <= 4)


# --- wear_item: slot / replacement semantics -------------------------------------------------


def test_wear_item_rejects_item_meant_for_a_different_slot(registry):
    human = make_character(registry, "human")
    assert human.wear_item("back", "leather_jacket", registry) is False  # leather_jacket is "torso"
    assert human.get_clothing("back") is None


def test_wear_item_replaces_whatever_was_in_that_slot(registry):
    human = make_character(registry, "human")
    human.wear_item("torso", "leather_jacket", registry)
    human.wear_item("torso", "reptilian_jacket", registry)
    assert human.get_clothing("torso").item_def_id == "reptilian_jacket"
    assert len([c for c in human.clothing if c.slot == "torso"]) == 1


def test_wear_item_does_not_replace_on_failed_fit_check(registry):
    reptilian = make_character(registry, "reptilian_quad")
    reptilian.wear_item("torso", "reptilian_jacket", registry)
    assert reptilian.wear_item("torso", "leather_jacket", registry) is False
    assert reptilian.get_clothing("torso").item_def_id == "reptilian_jacket"  # unchanged


def test_take_off_clears_a_slot(registry):
    human = make_character(registry, "human")
    human.wear_item("torso", "leather_jacket", registry)
    human.take_off("torso")
    assert human.get_clothing("torso") is None


def test_take_off_reveals_a_default_garment_underneath(registry):
    human = make_character(registry, "human", default_clothing=[ClothingPiece("torso", "leather_jacket")])
    human.wear_item("torso", "reptilian_jacket", registry)
    assert human.get_clothing("torso").item_def_id == "reptilian_jacket"
    human.take_off("torso")
    assert human.get_clothing("torso").item_def_id == "leather_jacket"  # fell back to the default