extends "res://tests/test_case.gd"

const NetInterpolator = preload("res://scripts/net_interpolator.gd")
const NetBodyState = preload("res://scripts/net_body_state.gd")


func test_extrapolation_integrates_angular_velocity() -> void:
	var interpolator := NetInterpolator.new()
	var first := NetBodyState.new()
	first.angular_velocity = Vector3.UP * PI
	interpolator.add_sample(1, first, 0)
	var second := first.copy()
	interpolator.add_sample(2, second, 0)
	var result := interpolator.sample_at(2.0 + 0.1 * 1000.0 / NetInterpolator.TICK_MS)
	assert_almost_eq(result.rotation.angle_to(Quaternion(Vector3.UP, PI * 0.1)), 0.0, 0.001, "present-time extrapolation advances rotation from angular velocity")


func test_stale_pre_reset_packet_cannot_reopen_an_old_epoch() -> void:
	var interpolator := NetInterpolator.new()
	interpolator.add_sample(10, NetBodyState.new(), 0)
	interpolator.add_sample(20, NetBodyState.new(), 1)
	assert_eq(interpolator.reset_gen, 1, "newer reset establishes the new epoch")
	assert_true(not interpolator.add_sample(15, NetBodyState.new(), 0), "late old-generation snapshot is rejected before reset handling")
	assert_eq(interpolator.reset_gen, 1, "stale packet cannot flip reset generation back")