refactor: separate action system responsibilities

simulation/actions/ActionSelectionSystem.gd

@@ -0,0 +1,81 @@
+class_name ActionSelectionSystem
+extends RefCounted
+
+func select_action(npc: SimNPC, village: SimVillage) -> ActionSelectionResult:
+	if npc.is_dead:
+		return null
+	if npc.is_starving:
+		if village.food > 0:
+			return ActionSelectionResult.new(SimulationIds.ACTION_EAT, 1.0)
+		return ActionSelectionResult.new(SimulationIds.ACTION_GATHER_FOOD, 4.0)
+	if npc.hunger > 75.0:
+		if village.food > 0:
+			return ActionSelectionResult.new(SimulationIds.ACTION_EAT)
+		return ActionSelectionResult.new(SimulationIds.ACTION_GATHER_FOOD)
+	if npc.energy < 25.0:
+		return ActionSelectionResult.new(SimulationIds.ACTION_REST)
+	return ActionSelectionResult.new(_choose_best_work_action(npc, village))
+
+func _choose_best_work_action(
+	npc: SimNPC,
+	village: SimVillage
+) -> StringName:
+	var scores := {
+		SimulationIds.ACTION_GATHER_FOOD: _calculate_score(
+			npc, SimulationIds.ACTION_GATHER_FOOD, village.food_priority,
+			village.food, 15.0, 30.0, 3.0, 1.5
+		),
+		SimulationIds.ACTION_GATHER_WOOD: _calculate_score(
+			npc, SimulationIds.ACTION_GATHER_WOOD, village.wood_priority,
+			village.wood, 10.0, 20.0, 2.5, 1.0
+		),
+		SimulationIds.ACTION_PATROL: _calculate_score(
+			npc, SimulationIds.ACTION_PATROL, village.safety_priority,
+			village.safety, 30.0, 50.0, 3.0, 1.5
+		),
+		SimulationIds.ACTION_STUDY: _calculate_score(
+			npc, SimulationIds.ACTION_STUDY, village.knowledge_priority,
+			village.knowledge, 10.0, 25.0, 1.5, 0.75
+		)
+	}
+	var best_action := SimulationIds.ACTION_GATHER_FOOD
+	var best_score: float = scores[best_action]
+	for action_id in [
+		SimulationIds.ACTION_GATHER_WOOD,
+		SimulationIds.ACTION_PATROL,
+		SimulationIds.ACTION_STUDY
+	]:
+		var score: float = scores[action_id]
+		if score > best_score:
+			best_action = action_id
+			best_score = score
+	return best_action
+
+func _calculate_score(
+	npc: SimNPC,
+	action_id: StringName,
+	base_priority: float,
+	resource_amount: float,
+	critical_threshold: float,
+	low_threshold: float,
+	critical_bonus: float,
+	low_bonus: float
+) -> float:
+	var score := base_priority
+	if resource_amount < critical_threshold:
+		score += critical_bonus
+	elif resource_amount < low_threshold:
+		score += low_bonus
+	var definition := SimulationDefinitions.get_action(action_id)
+	if (
+		definition != null
+		and not definition.preferred_profession_id.is_empty()
+		and npc.profession == definition.preferred_profession_id
+	):
+		score += 2.0
+	if action_id == npc.last_task:
+		score -= 1.5
+	score += npc.random_source.randf_range(0.0, 0.5)
+	if npc.debug_logs:
+		print("[ActionSelection] ", npc.npc_name, " score ", action_id, " = ", score)
+	return score