extends SceneTree
## Characterization test for the bull's damage reception. It pins the OBSERVABLE behaviour of
## take_sword_hit / apply_knock_up — pip loss, i-frame absorption, a single tagged death, and
## upward-only knock-up — before the WS2 slice reroutes them through DamageEvent, so the rewire can
## prove it changed nothing. When receive_damage(DamageEvent) lands, add a block that drives it and
## asserts the identical outcomes.
## Run: godot --headless --script tests/damage_pipeline_test.gd

var _pass := 0
var _fail := 0
var _died_count := 0
var _last_cause := ""
var _last_hp := -1


func _init() -> void:
	_run.call_deferred()


func _ok(cond: bool, msg: String) -> void:
	if cond:
		_pass += 1
		print("  PASS: ", msg)
	else:
		_fail += 1
		print("  FAIL: ", msg)


func _on_died(cause: String) -> void:
	_died_count += 1
	_last_cause = cause


func _on_health(current: int, _max_hp: int) -> void:
	_last_hp = current


func _run() -> void:
	(root.get_node("/root/Run") as Node).call("ensure_run")
	var scene: Node = load("res://scene.tscn").instantiate()
	root.add_child(scene)
	current_scene = scene
	await create_timer(0.8).timeout

	var players := get_nodes_in_group(&"player")
	_ok(not players.is_empty(), "bull present in the shell")
	if players.is_empty():
		return _finish()
	var bull: Node = players[0]
	bull.connect(&"died", _on_died)
	bull.connect(&"health_changed", _on_health)

	# Everything below runs synchronously (no await), so no physics frame or enemy turn interleaves —
	# the bull's state changes only from the calls under test.
	bull.set(&"_max_hp", 3)
	bull.set(&"_hp", 3)
	bull.set(&"_dead", false)
	bull.set(&"_hit_iframes", 0.0)
	bull.set(&"velocity", Vector3.ZERO)

	bull.call(&"take_sword_hit", "gored")
	_ok(int(bull.get(&"_hp")) == 2, "a clean hit removes one pip (3→2)")
	_ok(_last_hp == 2, "health_changed reports the new pip count")

	bull.call(&"take_sword_hit", "gored")
	_ok(int(bull.get(&"_hp")) == 2, "i-frames absorb a second hit in the same window")

	bull.set(&"_hit_iframes", 0.0)
	bull.call(&"take_sword_hit", "gored")
	_ok(int(bull.get(&"_hp")) == 1, "a hit after i-frames removes another pip (2→1)")

	bull.set(&"_hit_iframes", 0.0)
	bull.call(&"take_sword_hit", "gored")
	_ok(int(bull.get(&"_hp")) <= 0, "the last pip drops the bull")
	_ok(_died_count == 1, "died emits exactly once")
	_ok(_last_cause == "gored", "died carries the hit's cause")

	bull.set(&"_hit_iframes", 0.0)
	bull.call(&"take_sword_hit", "thrown")
	_ok(_died_count == 1, "a downed bull takes no further hits (death latches)")

	bull.set(&"velocity", Vector3.ZERO)
	bull.call(&"apply_knock_up", 5.0)
	_ok(is_equal_approx(float((bull.get(&"velocity") as Vector3).y), 5.0), "knock_up raises velocity.y to the pop")
	bull.call(&"apply_knock_up", 3.0)
	_ok(is_equal_approx(float((bull.get(&"velocity") as Vector3).y), 5.0), "a smaller knock_up never lowers it")
	bull.call(&"apply_knock_up", 8.0)
	_ok(is_equal_approx(float((bull.get(&"velocity") as Vector3).y), 8.0), "a larger knock_up raises it further")

	# The typed pipeline (Hitbox → DamageEvent → receive_damage) must produce identical outcomes to
	# the string path it now wraps.
	_last_hp = -1
	bull.set(&"_hp", 3)
	bull.set(&"_dead", false)
	bull.set(&"_hit_iframes", 0.0)
	bull.set(&"velocity", Vector3.ZERO)
	bull.call(&"receive_damage", DamageEvent.make(DamageEvent.Cause.MAULED, Vector3.ZERO))
	_ok(int(bull.get(&"_hp")) == 2, "receive_damage removes a pip like take_sword_hit")
	_ok(_last_hp == 2, "receive_damage emits health_changed with the new pip count")

	bull.set(&"_hit_iframes", 0.0)
	bull.set(&"velocity", Vector3.ZERO)
	var popping := DamageEvent.make(DamageEvent.Cause.SLAMMED, Vector3.ZERO)
	popping.knock_up = 6.0
	bull.call(&"receive_damage", popping)
	_ok(is_equal_approx(float((bull.get(&"velocity") as Vector3).y), 6.0), "receive_damage applies the event's knock_up")

	_finish()


func _finish() -> void:
	print("Results: %d passed, %d failed" % [_pass, _fail])
	quit(1 if _fail > 0 else 0)