from pathlib import Path

import pytest

from engine.character import Character
from engine.defs import DefRegistry
from resources.logic.combat import perform_attack

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)


class SequenceRng:
    """Deterministic stand-in: returns rolls from a fixed sequence, one call at a time."""

    def __init__(self, rolls: list[int], choice_value=None):
        self._rolls = list(rolls)
        self._choice_value = choice_value

    def randint(self, _lo, _hi):
        return self._rolls.pop(0)

    def choice(self, seq):
        return self._choice_value if self._choice_value is not None else seq[0]


def test_non_blocking_defender_uses_flat_difficulty(registry):
    attacker = make_human(registry)
    defender = make_human(registry)
    result = perform_attack(attacker, defender, registry, rng=SequenceRng([15], choice_value="torso"))
    assert result.blocked_check is False
    assert result.hit is True  # 15 > BASE_DIFFICULTY(10)


def test_blocking_defender_uses_opposed_check(registry):
    attacker = make_human(registry)
    attacker.bio["athletics"] = 0
    defender = make_human(registry, is_blocking=True)
    defender.bio["athletics"] = 15  # strong defense roll

    # attacker rolls 12, defender rolls 5 but has a high skill -> defender wins
    result = perform_attack(attacker, defender, registry, rng=SequenceRng([12, 5], choice_value="torso"))
    assert result.blocked_check is True
    assert result.hit is False


def test_blocking_defender_can_still_be_hit_if_attacker_beats_the_opposed_check(registry):
    attacker = make_human(registry)
    attacker.bio["athletics"] = 15
    defender = make_human(registry, is_blocking=True)
    defender.bio["athletics"] = 0

    result = perform_attack(attacker, defender, registry, rng=SequenceRng([18, 3], choice_value="torso"))
    assert result.blocked_check is True
    assert result.hit is True


def test_shield_bonus_helps_the_defender_block(registry):
    attacker = make_human(registry)  # bio athletics=0, so attacker_check == the raw roll

    unshielded = make_human(registry, is_blocking=True)
    shielded = make_human(registry, is_blocking=True)
    shielded.wield_item("left_hand", "wooden_shield", registry)

    # attacker rolls 10 (check=10), defender rolls 8 (check=8) both times;
    # only wooden_shield's +4 block bonus should flip the outcome
    result_unshielded = perform_attack(attacker, unshielded, registry, rng=SequenceRng([10, 8], choice_value="torso"))
    result_shielded = perform_attack(attacker, shielded, registry, rng=SequenceRng([10, 8], choice_value="torso"))

    assert result_unshielded.hit is True  # 10 > 8
    assert result_shielded.hit is False  # 10 < 8 + 4 (shield bonus)