extends SceneTree
## 玩家子弹弹道回归测试（时间驱动）：
## L4 齐射后快照所有子弹位置，0.25s 后比对实际位移方向，
## 必须命中 UP / ±22° / ±30° 五个弹道之一，且各组数量正确。
## 在 spawner 首波敌机（0.8s）出现前完成测量，保证确定性。
## 运行：godot --headless -s tests/bullet_traj_test.gd

const SNAP_DELAY := 0.1
const FLY_TIME := 0.25
const DOT_EPS := 0.995
const GLOBAL_TIMEOUT := 15.0

var _time := 0.0
var _snapped := false
var _game: Game
var _pbullets: Node2D
var _fails: Array[String] = []
var _snapshot: Array = []  # [bullet: Node2D, pos: Vector2]


func _initialize() -> void:
	_game = (load("res://scenes/game.tscn") as PackedScene).instantiate()
	root.add_child(_game)
	print("[traj_test] game instantiated")


func _fail(msg: String) -> void:
	_fails.append(msg)
	print("[FAIL] " + msg)


func _ensure_refs() -> bool:
	if _pbullets == null:
		_pbullets = _game.get_node_or_null("PlayerBullets") as Node2D
	return _pbullets != null


func _process(delta: float) -> bool:
	_time += delta
	if _time > GLOBAL_TIMEOUT:
		_fail("global timeout")
		return _finish()
	if not _ensure_refs():
		return false

	if not _snapped and _time >= SNAP_DELAY:
		_snapped = true
		# 先射一梭子 L4（fire 从首帧按住，此处已有一发齐射在飞）
		_game.player.weapon_level = 4
		Input.action_release("fire")
		_game.player._fire()
		_snapshot = []
		for bullet in _pbullets.get_children():
			_snapshot.append([bullet, (bullet as Node2D).position])
		if _snapshot.size() != 12:
			_fail("L4 volley=%d expected 12" % _snapshot.size())
		return false

	if _snapped and _time >= SNAP_DELAY + FLY_TIME:
		var allowed := [
			Vector2.UP,
			Vector2.UP.rotated(deg_to_rad(-22.0)),
			Vector2.UP.rotated(deg_to_rad(22.0)),
			Vector2.UP.rotated(deg_to_rad(-30.0)),
			Vector2.UP.rotated(deg_to_rad(30.0)),
		]
		var counts := [0, 0, 0, 0, 0]
		var classified := 0
		for entry in _snapshot:
			var bullet: Node2D = entry[0]
			var start: Vector2 = entry[1]
			if not is_instance_valid(bullet):
				_fail("bullet freed before measurement window ended")
				continue
			var disp: Vector2 = bullet.position - start
			if disp.length() < 50.0:
				_fail("bullet barely moved: %.1f px" % disp.length())
				continue
			var dir := disp.normalized()
			for i in allowed.size():
				if dir.dot(allowed[i]) >= DOT_EPS:
					counts[i] += 1
					classified += 1
					break
		if classified != _snapshot.size():
			_fail("only %d/%d bullets on valid trajectories" % [classified, _snapshot.size()])
		elif counts[0] != 6 or counts[1] != 2 or counts[2] != 2 or counts[3] != 1 or counts[4] != 1:
			_fail("trajectory group counts wrong: straight=%d L22=%d R22=%d L30=%d R30=%d" % counts)
		else:
			print("[traj_test] trajectories ok: straight=%d ±22=%d+%d ±30=%d+%d" % [counts[0], counts[1], counts[2], counts[3], counts[4]])
		return _finish()
	return false


func _finish() -> bool:
	if _fails.is_empty():
		print("[traj_test] PASS")
	else:
		print("[traj_test] FAIL: %d issue(s)" % _fails.size())
	quit(0 if _fails.is_empty() else 1)
	return true