feat: shared creature root, enemy definitions, defend duty, and player downing

simulation/state/player_state_record.gd

@@ -1,7 +1,9 @@
 class_name PlayerStateRecord
 extends RefCounted
 
-const SCHEMA_VERSION := 1
+const SCHEMA_VERSION := 2
+const LEGACY_SCHEMA_VERSION := 1
+const MAX_HEALTH := 100.0
 
 var data: Dictionary
 
@@ -18,6 +20,10 @@ static func create_default() -> PlayerStateRecord:
 				"schema_version": SCHEMA_VERSION,
 				"hunger": 40.0,
 				"energy": 100.0,
+				"health": MAX_HEALTH,
+				"max_health": MAX_HEALTH,
+				"downed": false,
+				"downed_ticks": 0,
 				"inventory": {},
 			}
 		)
@@ -25,15 +31,27 @@ static func create_default() -> PlayerStateRecord:
 
 
 static func from_dictionary(record_data: Dictionary) -> PlayerStateRecord:
-	if int(record_data.get("schema_version", -1)) != SCHEMA_VERSION:
+	var version := int(record_data.get("schema_version", -1))
+	if version == LEGACY_SCHEMA_VERSION:
+		record_data = _migrate_v1(record_data)
+	elif version != SCHEMA_VERSION:
 		return null
-	if not record_data.has_all(["hunger", "energy", "inventory"]):
+	if not record_data.has_all(
+		["hunger", "energy", "health", "max_health", "downed", "downed_ticks", "inventory"]
+	):
 		return null
 	if not record_data["inventory"] is Dictionary:
 		return null
 	var hunger := float(record_data["hunger"])
 	var energy := float(record_data["energy"])
-	if not is_finite(hunger) or not is_finite(energy):
+	var health := float(record_data["health"])
+	var max_health := float(record_data["max_health"])
+	if (
+		not is_finite(hunger)
+		or not is_finite(energy)
+		or not is_finite(health)
+		or not is_finite(max_health)
+	):
 		return null
 	var normalized_inventory := {}
 	for raw_item_id in record_data["inventory"]:
@@ -54,12 +72,26 @@ static func from_dictionary(record_data: Dictionary) -> PlayerStateRecord:
 				"schema_version": SCHEMA_VERSION,
 				"hunger": clampf(hunger, 0.0, 100.0),
 				"energy": clampf(energy, 0.0, 100.0),
+				"health": clampf(health, 0.0, max_health),
+				"max_health": max_health,
+				"downed": bool(record_data["downed"]),
+				"downed_ticks": int(record_data["downed_ticks"]),
 				"inventory": normalized_inventory,
 			}
 		)
 	)
 
 
+static func _migrate_v1(legacy_data: Dictionary) -> Dictionary:
+	var migrated := legacy_data.duplicate(true)
+	migrated["schema_version"] = SCHEMA_VERSION
+	migrated["health"] = MAX_HEALTH
+	migrated["max_health"] = MAX_HEALTH
+	migrated["downed"] = false
+	migrated["downed_ticks"] = 0
+	return migrated
+
+
 func get_hunger() -> float:
 	return clampf(float(data["hunger"]), 0.0, 100.0)
 
@@ -68,6 +100,22 @@ func get_energy() -> float:
 	return clampf(float(data["energy"]), 0.0, 100.0)
 
 
+func get_health() -> float:
+	return clampf(float(data["health"]), 0.0, get_max_health())
+
+
+func get_max_health() -> float:
+	return maxf(float(data["max_health"]), 1.0)
+
+
+func is_downed() -> bool:
+	return bool(data["downed"])
+
+
+func get_downed_ticks() -> int:
+	return int(data["downed_ticks"])
+
+
 func set_hunger(amount: float) -> void:
 	data["hunger"] = clampf(amount, 0.0, 100.0)
 
@@ -76,6 +124,28 @@ func set_energy(amount: float) -> void:
 	data["energy"] = clampf(amount, 0.0, 100.0)
 
 
+func take_damage(amount: float) -> float:
+	if not is_finite(amount) or amount <= 0.0 or is_downed():
+		return 0.0
+	var previous := get_health()
+	data["health"] = clampf(previous - amount, 0.0, get_max_health())
+	if get_health() <= 0.0:
+		data["downed"] = true
+		data["downed_ticks"] = 20
+	return previous - get_health()
+
+
+func advance_health() -> void:
+	if is_downed():
+		data["downed_ticks"] = maxi(get_downed_ticks() - 1, 0)
+		if get_downed_ticks() <= 0:
+			data["downed"] = false
+			data["health"] = get_max_health() * 0.5
+		return
+	if get_health() < get_max_health():
+		data["health"] = clampf(get_health() + 0.25, 0.0, get_max_health())
+
+
 func get_inventory_amount(item_id: StringName) -> float:
 	return float(data["inventory"].get(String(item_id), 0.0))