"""Cure spells damage undead instead of healing (Task 11 conformance).

SRD "Cure Light Wounds" (spells/cure-light-wounds.md): "Since undead are
powered by negative energy, this spell deals damage to them instead of curing
their wounds. An undead creature can apply spell resistance, and can attempt
a Will save to take half damage." The engine resolves SR upstream and the
rolled Will save halves the damage here; living targets keep healing exactly
as before.
"""

from __future__ import annotations

from typing import TYPE_CHECKING

from tests.test_spells import _make_caster, _make_engine, _make_target

if TYPE_CHECKING:
    from pf1e_simulator.models import Combatant


def _undead(cid: str = "skeleton", *, hp_max: int = 20) -> Combatant:
    return _make_target(cid=cid, hp_max=hp_max).model_copy(
        update={"creature_type": "undead"}
    )


def _caster() -> Combatant:
    return _make_caster().model_copy(update={"spells": ["Cure Light Wounds"]})


class TestCureDamagesUndead:
    """Given: a level-5 caster (Cure Light Wounds = 1d8+5) and an undead target

    When: the cure spell is delivered
    Then: the undead takes damage instead of healing.
    """

    def test_failed_save_deals_full_damage(self) -> None:
        """Given: an undead at 20 hp
        When: cured and it fails the Will save (d20=1), the die rolls 8
        Then: it takes the full 13 damage (8+5) instead of healing."""
        engine, c, t = _make_engine(
            _caster(), _undead(), [1, 8], target_pos=(1, 0), target_side="players"
        )
        engine._cast_spell(c, t, "Cure Light Wounds")
        assert t.hp == 7
        assert any("13 damage (undead)" in line for line in engine._transcript)

    def test_successful_save_halves_the_damage(self) -> None:
        """Given: an undead at 20 hp
        When: cured and it succeeds the Will save (natural 20), the die rolls 8
        Then: it takes half damage (13 // 2 = 6)."""
        engine, c, t = _make_engine(
            _caster(), _undead(), [20, 8], target_pos=(1, 0), target_side="players"
        )
        engine._cast_spell(c, t, "Cure Light Wounds")
        assert t.hp == 14
        assert any("6 damage (undead)" in line for line in engine._transcript)

    def test_undead_destroyed_by_cure_damage(self) -> None:
        """Given: an undead at 10 hp
        When: a failed-save cure deals 13 damage
        Then: the undead is destroyed (undead die at hp <= 0)."""
        engine, c, t = _make_engine(
            _caster(), _undead(hp_max=10), [1, 8], target_pos=(1, 0), target_side="players"
        )
        engine._cast_spell(c, t, "Cure Light Wounds")
        assert t.dead is True

    def test_living_target_still_heals(self) -> None:
        """Given: a living ally at 5/20 hp
        When: cured with a die roll of 8
        Then: it heals 13 hp (behavior unchanged for the living)."""
        engine, c, t = _make_engine(
            _caster(), _make_target(), [1, 8], target_pos=(1, 0), target_side="players"
        )
        t.hp = 5
        engine._cast_spell(c, t, "Cure Light Wounds")
        assert t.hp == 18
        assert any("+13 HP" in line for line in engine._transcript)


class TestCureUndeadAttrition:
    """Given: a cure spell delivered to an undead
    When: the negative-energy damage lands
    Then: it counts as damage in attrition (dealer + taker), while healing a
    living target records no damage either way."""

    def test_undead_damage_recorded_for_both_sides(self) -> None:
        engine, c, t = _make_engine(
            _caster(), _undead(), [1, 8], target_pos=(1, 0), target_side="players"
        )
        engine._cast_spell(c, t, "Cure Light Wounds")
        assert engine._stats["skeleton"].damage_taken == 13
        assert engine._stats["caster"].damage_dealt == 13

    def test_living_heal_records_no_damage(self) -> None:
        engine, c, t = _make_engine(
            _caster(), _make_target(), [1, 8], target_pos=(1, 0), target_side="players"
        )
        t.hp = 5
        engine._cast_spell(c, t, "Cure Light Wounds")
        assert engine._stats["caster"].damage_dealt == 0
        assert engine._stats["target"].damage_taken == 0