Implement production vertical slice foundation

game/domain/dive/dive_step.gd

@@ -0,0 +1,70 @@
+class_name DiveStep
+extends RefCounted
+
+const DiveTick = preload("res://game/domain/dive/dive_tick.gd")
+const DiveTelemetrySample = preload("res://game/domain/dive/dive_telemetry_sample.gd")
+const CollisionObservation = preload("res://game/domain/dive/collision_observation.gd")
+const ToolPowerDemand = preload("res://game/domain/dive/tool_power_demand.gd")
+const EjectionIntent = preload("res://game/domain/dive/ejection_intent.gd")
+const ReturnRouteSample = preload("res://game/domain/dive/return_route_sample.gd")
+
+var tick: DiveTick
+var telemetry: DiveTelemetrySample
+var collisions: Array[CollisionObservation]
+var tool_power_demands: Array[ToolPowerDemand]
+var ejection_intent: EjectionIntent
+var return_route: ReturnRouteSample
+
+
+func _init(
+	p_tick: DiveTick,
+	p_telemetry: DiveTelemetrySample,
+	p_collisions: Array[CollisionObservation] = [],
+	p_tool_power_demands: Array[ToolPowerDemand] = [],
+	p_ejection_intent: EjectionIntent = null,
+	p_return_route: ReturnRouteSample = null
+) -> void:
+	tick = p_tick
+	telemetry = p_telemetry
+	collisions = p_collisions.duplicate()
+	tool_power_demands = p_tool_power_demands.duplicate()
+	ejection_intent = p_ejection_intent if p_ejection_intent != null else EjectionIntent.new()
+	return_route = p_return_route if p_return_route != null else ReturnRouteSample.new()
+
+
+func validation_error() -> String:
+	if tick == null:
+		return "DiveStep has no tick"
+	var error: String = tick.validation_error()
+	if not error.is_empty():
+		return error
+	if telemetry == null:
+		return "DiveStep has no telemetry"
+	error = telemetry.validation_error()
+	if not error.is_empty():
+		return error
+	if ejection_intent == null:
+		return "DiveStep has no ejection intent"
+	if return_route == null:
+		return "DiveStep has no return route sample"
+	error = return_route.validation_error()
+	if not error.is_empty():
+		return error
+	for collision: CollisionObservation in collisions:
+		if collision == null:
+			return "DiveStep contains a null collision"
+		error = collision.validation_error(tick.sequence)
+		if not error.is_empty():
+			return error
+	for demand: ToolPowerDemand in tool_power_demands:
+		if demand == null:
+			return "DiveStep contains a null tool power demand"
+		error = demand.validation_error()
+		if not error.is_empty():
+			return error
+	var tool_ids: Dictionary[StringName, bool] = {}
+	for demand: ToolPowerDemand in tool_power_demands:
+		if tool_ids.has(demand.tool_id):
+			return "DiveStep contains duplicate tool power demands"
+		tool_ids[demand.tool_id] = true
+	return ""