class_name CollisionObservation
extends RefCounted

var observation_id: StringName
var sequence: int
var tick_sequence: int
var normal_impact_speed_mps: float


func _init(
	p_observation_id: StringName,
	p_sequence: int,
	p_tick_sequence: int,
	p_normal_impact_speed_mps: float
) -> void:
	observation_id = p_observation_id
	sequence = p_sequence
	tick_sequence = p_tick_sequence
	normal_impact_speed_mps = p_normal_impact_speed_mps


func validation_error(expected_tick_sequence: int) -> String:
	if observation_id.is_empty():
		return "collision observation_id is empty"
	if sequence < 0:
		return "collision sequence is negative"
	if tick_sequence != expected_tick_sequence:
		return "collision tick sequence does not match DiveTick"
	if not is_finite(normal_impact_speed_mps) or normal_impact_speed_mps < 0.0:
		return "collision speed must be finite and non-negative"
	return ""