feat: save energy state

godot/addons/save-system/SaveManager.gd

@@ -27,12 +27,12 @@ func load_from_slot(slot: int):
 	var file = FileAccess.open(file_name, FileAccess.READ)
 	var data
 	if file == null:
-		logger.error("Failed to load data from %s: %s" % [file_name, file.get_open_error()])
+		logger.error("Failed to load data from %s" % [file_name])
 	else:
 		data = file.get_var()
 		if data:
 			logger.debug("Load %s" % str(data))
-	file.close()
+		file.close()
 
 	return data
 

godot/src/Energy.gd

@@ -0,0 +1,14 @@
+extends Node
+
+@export var max_energy := 5
+@onready var energy := max_energy : set = _set_energy
+
+func _set_energy(v):
+	energy = v
+	GameManager.energy_updated.emit(energy)
+
+func use_energy():
+	if energy > 0:
+		self.energy -= 1
+		return true
+	return false

godot/src/game_manager.gd

@@ -2,21 +2,40 @@ extends Node
 
 signal energy_updated(energy)
 
+const SAVE_SLOT = 0
+
+@onready var save_manager := $SaveManager
+@onready var energy := $Energy
+
 var points := 0
 
-var max_energy := 5
-@onready var energy := max_energy : set = _set_energy
+func _ready():
+	_load_game()
 
-func _set_energy(v):
-	energy = v
-	energy_updated.emit(energy)
+func _exit_tree():
+	_save_game()
 
 func scored(score: int):
 	points += floor(score / 100)
 
 func start_game():
-	if energy > 0:
-		self.energy -= 1
+	if energy.use_energy():
 		SceneManager.change_scene("res://src/game.tscn")
 	else:
 		print("No energy")
+
+func get_energy():
+	return energy.energy
+
+func _save_game():
+	save_manager.save_to_slot(SAVE_SLOT, {
+		"energy": get_energy()
+	})
+
+func _load_game():
+	var data = save_manager.load_from_slot(SAVE_SLOT)
+	if data == null:
+		return
+
+	if "energy" in data:
+		energy.energy = data.energy

godot/src/game_manager.tscn

@@ -1,6 +1,14 @@
-[gd_scene load_steps=2 format=3 uid="uid://cn81olkklufoh"]
+[gd_scene load_steps=4 format=3 uid="uid://cn81olkklufoh"]
 
 [ext_resource type="Script" path="res://src/game_manager.gd" id="1_hnxtg"]
+[ext_resource type="Script" path="res://addons/save-system/SaveManager.gd" id="2_etxdi"]
+[ext_resource type="Script" path="res://src/Energy.gd" id="3_vf6rt"]
 
 [node name="GameManager" type="Node"]
 script = ExtResource("1_hnxtg")
+
+[node name="SaveManager" type="Node" parent="."]
+script = ExtResource("2_etxdi")
+
+[node name="Energy" type="Node" parent="."]
+script = ExtResource("3_vf6rt")

godot/src/menu/energy_container.gd

@@ -2,7 +2,7 @@ class_name EnergyContainer
 extends Control
 
 func _ready():
-	set_energy(GameManager.energy)
+	set_energy(GameManager.get_energy())
 
 func set_energy(v):
 	for i in get_child_count():