from pathlib import Path

import pytest

from engine.character import BodyPart, Character
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_human(registry, **kwargs) -> Character:
    return Character(species_id="human", default_body_parts=registry.new_default_body_parts("human"), **kwargs)


def test_wield_one_handed_item_in_a_hand(registry):
    character = make_human(registry)
    assert character.wield_item("right_hand", "staff_oak", registry) is True
    assert character.get_held_item("right_hand").item_def_id == "staff_oak"
    assert character.get_held_item("left_hand") is None


def test_wield_fails_without_the_corresponding_arm(registry):
    character = make_human(registry)
    character.body_parts = [BodyPart("right_arm", "human_right_arm", removed=True)]
    assert character.wield_item("right_hand", "staff_oak", registry) is False
    assert character.get_held_item("right_hand") is None


def test_two_handed_item_occupies_both_hands(registry):
    character = make_human(registry)
    assert character.wield_item("right_hand", "multi_deconstructor", registry) is True
    assert character.get_held_item("right_hand").item_def_id == "multi_deconstructor"
    assert character.get_held_item("left_hand").item_def_id == "multi_deconstructor"


def test_two_handed_item_fails_if_paired_arm_missing(registry):
    character = make_human(registry)
    character.body_parts = [BodyPart("left_arm", "human_left_arm", removed=True)]
    assert character.wield_item("right_hand", "multi_deconstructor", registry) is False
    assert character.held_items == []  # no partial wield


def test_wielding_replaces_whatever_was_in_that_hand(registry):
    character = make_human(registry)
    character.wield_item("right_hand", "staff_oak", registry)
    character.wield_item("right_hand", "pistol_basic", registry)
    assert character.get_held_item("right_hand").item_def_id == "pistol_basic"
    assert len([h for h in character.held_items if h.hand_slot == "right_hand"]) == 1


def test_two_handed_wield_clears_a_previously_one_handed_offhand_item(registry):
    character = make_human(registry)
    character.wield_item("left_hand", "wooden_shield", registry)
    character.wield_item("right_hand", "multi_deconstructor", registry)
    assert character.get_held_item("left_hand").item_def_id == "multi_deconstructor"
    assert character.get_held_item("right_hand").item_def_id == "multi_deconstructor"


def test_unwield_clears_a_hand(registry):
    character = make_human(registry)
    character.wield_item("right_hand", "staff_oak", registry)
    character.unwield("right_hand")
    assert character.get_held_item("right_hand") is None


def test_four_armed_hand_slots_unavailable_on_a_two_armed_human(registry):
    character = make_human(registry)
    assert character.wield_item("right_hand_2", "staff_oak", registry) is False


def test_wielded_shield_detects_shield_by_stats(registry):
    character = make_human(registry)
    assert character.wielded_shield(registry) is None
    character.wield_item("left_hand", "wooden_shield", registry)
    shield = character.wielded_shield(registry)
    assert shield is not None
    assert shield.id == "wooden_shield"


def test_wielded_shield_ignores_non_shield_items(registry):
    character = make_human(registry)
    character.wield_item("right_hand", "staff_oak", registry)
    assert character.wielded_shield(registry) is None