extends SceneTree
## Bear ram test. Running the bull HORNS-FIRST into the bear should wound it. The bear detects this by
## sweeping the bull's actual travel (prev → now) against its body each frame (bear._sweep_bull_ram),
## gated by speed (bear_hit_threshold), reach (bear_ram_reach) and a horns-first cone (bull_gore_arc),
## and edge-triggered so one charge = one wound. This drives passes against a frozen bear and asserts:
## a horns-first charge (even one that tunnels / starts close) wounds it once; a charge moving AWAY
## (bear behind the horns), a pass out of reach, and a too-slow nudge all leave it unharmed.
## Run: godot --headless --script res://tests/bear_ram_test.gd

var _pass := 0
var _fail := 0


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


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


func _make_bull() -> CharacterBody3D:
	var b := CharacterBody3D.new()
	b.set_script(load("res://tests/_fake_bull.gd"))   # exposes is_dashing()/is_rolling()
	b.collision_layer = 2
	b.collision_mask = 0
	b.add_to_group(&"player")
	var cs := CollisionShape3D.new()
	var shape := CapsuleShape3D.new()
	shape.radius = 0.75
	shape.height = 1.845
	cs.shape = shape
	b.add_child(cs)
	root.add_child(b)
	return b


# Sweep the bull from `from` to `to` at `speed` (velocity along the travel), reseting the bear's ram
# edge-state first so each pass is isolated. The prev → now segment is what the bear tests against.
func _ram_pass(bear: Node, bull: CharacterBody3D, speed: float, from: Vector3, to: Vector3) -> void:
	bear.set("_bull_prev_seen", false)
	bear.set("_bull_ramming", false)
	var dir := to - from
	dir.y = 0.0
	bull.velocity = dir.normalized() * speed if dir.length() > 0.01 else Vector3.ZERO
	bull.global_position = from
	bear.call("_sweep_bull_ram")
	bull.global_position = to
	bear.call("_sweep_bull_ram")


func _run() -> void:
	var bull := _make_bull()
	var bear := (load("res://Bear.tscn") as PackedScene).instantiate() as Node3D
	root.add_child(bear)
	bear.global_position = Vector3.ZERO
	bear.set_physics_process(false)   # freeze the AI; we drive the ram sweep ourselves
	await physics_frame
	bear.call("_acquire_bull")

	var dp := root.get_node("/root/DP")
	var reach: float = dp.f("bear_ram_reach")
	var thr: float = dp.f("bear_hit_threshold")
	_ok(bear.get("_bull") == bull, "bear acquired the bull")

	# (a) Horns-first charge straight through the bear — endpoints (3 m) sit outside the reach, so
	# only the swept test catches the pass-through.
	var hp0: int = bear.get("_hp")
	_ok(3.0 > reach, "test pass tunnels: endpoints (3 m) exceed the ram reach (%.2f m)" % reach)
	_ram_pass(bear, bull, 66.0, Vector3(-3, 0, 0), Vector3(3, 0, 0))
	_ok(bear.get("_hp") == hp0 - 1, "a horns-first charge wounds the bear once")

	# (b) One charge = one wound: sweeping the same charge again without disengaging doesn't re-hit
	# mid-contact (edge-triggered). Re-seed as if the bull never left the ram — no reset.
	var hp1: int = bear.get("_hp")
	bull.velocity = Vector3(66, 0, 0)
	bull.global_position = Vector3(0.2, 0, 0)   # still on top of the bear, still charging
	bear.call("_sweep_bull_ram")
	_ok(bear.get("_hp") == hp1, "a sustained charge doesn't drain the bear frame-by-frame")

	# (c) Charging AWAY (bear behind the horns) is not a horns-first ram, even up close.
	var hp2: int = bear.get("_hp")
	_ram_pass(bear, bull, 66.0, Vector3(0.5, 0, 0), Vector3(4, 0, 0))
	_ok(bear.get("_hp") == hp2, "a charge moving away from the bear leaves it unharmed")

	# (d) A fast pass wide of the bear (out of reach) is spared.
	_ram_pass(bear, bull, 66.0, Vector3(-3, 0, 3), Vector3(3, 0, 3))
	_ok(bear.get("_hp") == hp2, "a charge that passes wide of the bear is spared")

	# (e) A slow nudge below the hit threshold is shrugged off.
	_ram_pass(bear, bull, thr - 1.0, Vector3(-3, 0, 0), Vector3(3, 0, 0))
	_ok(bear.get("_hp") == hp2, "a nudge below the hit threshold doesn't wound the bear")

	# (f) The DASH ability bypasses the horns-first cone: the same charge-away pass that (c) shrugged
	# off DOES wound the bear while dashing (a committed lunge rams on contact).
	var hp3: int = bear.get("_hp")
	bull.set("dashing", true)
	_ram_pass(bear, bull, 66.0, Vector3(0.5, 0, 0), Vector3(4, 0, 0))
	_ok(bear.get("_hp") == hp3 - 1, "the dash ability rams the bear on contact even when not horns-first")
	bull.set("dashing", false)

	_finish()


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