feat: define reusable animal archetypes

simulation/state/animal_state_record.gd

@@ -4,12 +4,14 @@ extends RefCounted
 signal changed(state: AnimalStateRecord)
 signal fed(state: AnimalStateRecord, actor_id: int)
 
-const SCHEMA_VERSION := 2
+const SCHEMA_VERSION := 3
+const ROUTINE_SCHEMA_VERSION := 2
 const LEGACY_SCHEMA_VERSION := 1
 const HUNGER_PER_TICK := 0.125
 const FEED_THRESHOLD := 65.0
 const HUNGER_RELIEF := 55.0
 const NEVER_FED_TICK := -1
+const LEGACY_DEFINITION_BY_SPECIES := {"goat": "domestic_goat"}
 
 var data: Dictionary
 
@@ -25,6 +27,7 @@ static func create_from_node(node: AnimalNode) -> AnimalStateRecord:
 			{
 				"schema_version": SCHEMA_VERSION,
 				"animal_id": String(node.animal_id),
+				"animal_definition_id": String(node.animal_definition_id),
 				"display_name": node.display_name,
 				"species_id": String(node.species_id),
 				"position":
@@ -49,6 +52,8 @@ static func from_dictionary(record_data: Dictionary) -> AnimalStateRecord:
 	var version := int(record_data.get("schema_version", -1))
 	if version == LEGACY_SCHEMA_VERSION:
 		record_data = _migrate_legacy(record_data)
+	elif version == ROUTINE_SCHEMA_VERSION:
+		record_data = _migrate_definition_identity(record_data)
 	elif version != SCHEMA_VERSION:
 		return null
 	if not (
@@ -56,6 +61,7 @@ static func from_dictionary(record_data: Dictionary) -> AnimalStateRecord:
 		. has_all(
 			[
 				"animal_id",
+				"animal_definition_id",
 				"display_name",
 				"species_id",
 				"position",
@@ -75,6 +81,7 @@ static func from_dictionary(record_data: Dictionary) -> AnimalStateRecord:
 	):
 		return null
 	var animal_id := String(record_data["animal_id"])
+	var animal_definition_id := String(record_data["animal_definition_id"])
 	var display_name := String(record_data["display_name"])
 	var species_id := String(record_data["species_id"])
 	var saved_position = record_data["position"]
@@ -87,9 +94,12 @@ static func from_dictionary(record_data: Dictionary) -> AnimalStateRecord:
 	var has_travel_target := bool(record_data["has_travel_target"])
 	var next_routine_tick := int(record_data["next_routine_tick"])
 	var enabled := bool(record_data["enabled"])
-	if animal_id.is_empty() or display_name.is_empty() or species_id.is_empty():
-		return null
-	if StringName(species_id) != SimulationIds.SPECIES_GOAT:
+	if (
+		not AnimalDefinition.is_valid_stable_id(animal_id)
+		or not AnimalDefinition.is_valid_stable_id(animal_definition_id)
+		or display_name.is_empty()
+		or not AnimalDefinition.is_valid_stable_id(species_id)
+	):
 		return null
 	if not saved_position is Array or saved_position.size() != 3:
 		return null
@@ -120,6 +130,7 @@ static func from_dictionary(record_data: Dictionary) -> AnimalStateRecord:
 	var normalized := record_data.duplicate(true)
 	normalized["schema_version"] = SCHEMA_VERSION
 	normalized["animal_id"] = animal_id
+	normalized["animal_definition_id"] = animal_definition_id
 	normalized["display_name"] = display_name
 	normalized["species_id"] = species_id
 	normalized["position"] = [
@@ -145,7 +156,8 @@ func apply_definition(node: AnimalNode) -> bool:
 	if node == null or node.animal_id != get_animal_id():
 		return false
 	return (
-		node.display_name == get_display_name()
+		node.animal_definition_id == get_animal_definition_id()
+		and node.display_name == get_display_name()
 		and node.species_id == get_species_id()
 		and node.can_npcs_feed == can_npc_feed()
 		and node.can_player_feed == can_player_feed_animal()
@@ -156,6 +168,10 @@ func get_animal_id() -> StringName:
 	return StringName(data["animal_id"])
 
 
+func get_animal_definition_id() -> StringName:
+	return StringName(data["animal_definition_id"])
+
+
 func get_display_name() -> String:
 	return String(data["display_name"])
 
@@ -350,10 +366,18 @@ func to_dictionary() -> Dictionary:
 
 static func _migrate_legacy(record_data: Dictionary) -> Dictionary:
 	var migrated := record_data.duplicate(true)
-	migrated["schema_version"] = SCHEMA_VERSION
+	migrated["schema_version"] = ROUTINE_SCHEMA_VERSION
 	migrated["routine_site_id"] = ""
 	migrated["travel_target_site_id"] = ""
 	migrated["travel_target_position"] = [0.0, 0.0, 0.0]
 	migrated["has_travel_target"] = false
 	migrated["next_routine_tick"] = 0
+	return _migrate_definition_identity(migrated)
+
+
+static func _migrate_definition_identity(record_data: Dictionary) -> Dictionary:
+	var migrated := record_data.duplicate(true)
+	migrated["schema_version"] = SCHEMA_VERSION
+	var species_id := String(migrated.get("species_id", ""))
+	migrated["animal_definition_id"] = String(LEGACY_DEFINITION_BY_SPECIES.get(species_id, ""))
 	return migrated