Enhance save system functionality; improve game state management and session tracking

autoloads/save_system.gd

@@ -1,4 +1,3 @@
-class_name SaveSystem
 extends Node
 
 @export var save_path: String = "user://savegame.save"
@@ -15,18 +14,32 @@ func save_game():
 	var file      := FileAccess.open(save_path, FileAccess.WRITE)
 	file.store_var(save_data)
 	file.close()
+	print("Game saved to: ", save_path)
 
 
-func load_game():
+func load_game() -> bool:
 	if not FileAccess.file_exists(save_path):
-		return
+		return false
 	var file                  := FileAccess.open(save_path, FileAccess.READ)
 	var save_data: Dictionary =  file.get_var()
 	file.close()
 
 	if save_data.has("version") and save_data["version"] != version:
 		print("Save file version mismatch. Expected: ", version, ", Found: ", save_data["version"])
-		return
+		return false
 
+	print("save data: ", save_data)
 	gm.player_state = save_data["player_state"]
-	gm.unlock_skills(gm.player_state["unlocked_skills"])
+	print("Player state loaded: ", gm.player_state)
+	var skills: Array[String] = []
+	for skill_name in gm.player_state["unlocked_skills"]:
+		skills.append(skill_name)
+
+	print("Newly unlocked skills: ", skills)
+	gm.unlock_skills(skills)
+	print("Game loaded from: ", save_path)
+	return true
+
+
+func check_save_exists() -> bool:
+	return FileAccess.file_exists(save_path)

project.godot

@@ -36,6 +36,7 @@ Console="*res://addons/console/console.gd"
 AchievementsManager="*res://objects/achievements.tscn"
 ConfigFileHandler="*res://autoloads/config_file_handler.gd"
 UiManager="*res://autoloads/ui_manager.gd"
+SaveSystem="*res://autoloads/save_system.gd"
 
 [debug]
 

scenes/level_village_2.tscn

@@ -75,8 +75,9 @@ player_health = NodePath("../../Brick Player/HealthComponent")
 current_level = SubResource("Resource_bqjcg")
 nodes_to_disable = [NodePath("../../Brick Player")]
 
-[node name="Marketplace" parent="UI Layer" index="3" node_paths=PackedStringArray("skill_unlocker")]
+[node name="Marketplace" parent="UI Layer" index="3" node_paths=PackedStringArray("skill_unlocker", "components_to_disable")]
 skill_unlocker = NodePath("../../Brick Player/SkillUnlockerComponent")
+components_to_disable = [NodePath("../../Brick Player")]
 
 [node name="Global Light" parent="." instance=ExtResource("4_wykfl")]
 

scripts/components/exit_door_component.gd

@@ -36,4 +36,4 @@ func on_exit_area_body_entered(_body: Node2D) -> void:
 
 
 func go_to_next_level() -> void:
-	gm.try_to_go_to_next_level()
+	gm.on_level_complete()

scripts/components/player_death.gd

@@ -17,5 +17,5 @@ func _on_health_component_on_death() -> void:
 		effect.scale = Vector2(1.5, 1.5)
 
 	gm.remove_lives(1)
-	gm.set_coins(0)
+	gm.reset_current_session_state()
 		

scripts/components/score.gd

@@ -6,10 +6,10 @@ extends Node
 
 func _ready():
 	await get_tree().process_frame
-	var coins = get_tree().get_nodes_in_group("coins")
+	var coins := get_tree().get_nodes_in_group("coins")
 
 	for coin in coins:
-		coin.connect("collected", on_collected)
+		coin.collected.connect(on_collected)
 
 
 func on_collected(amount: int, type: CollectableResource.CollectableType) -> void:
@@ -17,4 +17,4 @@ func on_collected(amount: int, type: CollectableResource.CollectableType) -> voi
 		return
 	if type != CollectableResource.CollectableType.COIN:
 		return
-	game_manager.add_coins(amount)
+	game_manager.current_session_state["coins_collected"] += amount

scripts/components/skill_unlocker_component.gd

@@ -6,6 +6,11 @@ extends Node
 @onready var game_manager: GM = $"/root/GameManager"
 
 
+
+func has_enough_coins(amount: int) -> bool:
+	return game_manager and game_manager.get_coins() >= amount
+
+
 func try_unlock_skill(skill_data: SkillData) -> bool:
 	if not game_manager:
 		return false
@@ -13,11 +18,11 @@ func try_unlock_skill(skill_data: SkillData) -> bool:
 	if game_manager.is_skill_unlocked(skill_data.name):
 		return false
 
-	if game_manager.get_coins() < skill_data.cost:
+	if not has_enough_coins(skill_data.cost):
 		return false
 
 	game_manager.remove_coins(skill_data.cost)
-	game_manager.unlock_skill(skill_data.name)
+	game_manager.current_session_state["unlocked_skills"].append(skill_data.name)
 	skill_manager.add_skill(skill_data)
 	return true
 
@@ -31,8 +36,3 @@ func unlock_all_skills() -> void:
 
 	game_manager.unlock_skills(skills)
 	skill_manager.apply_unlocked_skills()
-
-
-func _input(event: InputEvent) -> void:
-	if event.is_action_pressed("unlock_skills"):
-		unlock_all_skills()

scripts/game_manager.gd

@@ -9,11 +9,18 @@ extends Node
 								"unlocked_skills": [],
 								"current_level": 0,
 								"unlocked_levels": [],
+								"completed_levels": [],
 							}
 
 var nodes_in_scene := []
 
 
+var current_session_state := {
+								 "coins_collected": 0,
+								 "skills_unlocked": [],
+							 }
+
+
 func _enter_tree() -> void:
 	get_tree().node_added.connect(on_node_added)
 	get_tree().node_removed.connect(on_node_removed)
@@ -64,6 +71,7 @@ func get_kid_nodes() -> Array[CollectableComponent]:
 
 func add_coins(amount: int) -> void:
 	player_state["coins"] += amount
+	player_state["coins"] = max(0, player_state["coins"])
 
 
 func set_coins(amount: int) -> void:
@@ -71,11 +79,20 @@ func set_coins(amount: int) -> void:
 
 
 func get_coins() -> int:
-	return player_state["coins"]
+	return player_state["coins"] + current_session_state["coins_collected"]
 
 
 func remove_coins(amount: int) -> void:
-	player_state["coins"] -= amount
+	var session_coins = current_session_state["coins_collected"]
+
+	if amount <= session_coins:
+		current_session_state["coins_collected"] -= amount
+	else:
+		var remaining_amount = amount - session_coins
+		current_session_state["coins_collected"] = 0
+		player_state["coins"] = max(0, player_state["coins"] - remaining_amount)
+
+	player_state["coins"] = max(0, player_state["coins"])
 
 
 func add_lives(amount: int) -> void:
@@ -95,7 +112,7 @@ func get_lives() -> int:
 
 
 func is_skill_unlocked(skill_name: String) -> bool:
-	return skill_name in player_state["unlocked_skills"]
+	return skill_name in player_state["unlocked_skills"] or skill_name in current_session_state["skills_unlocked"]
 
 
 func unlock_skill(skill_name: String) -> void:
@@ -118,6 +135,7 @@ func reset_player_state() -> void:
 		"coins": 0,
 		"lives": 3,
 		"unlocked_skills": [],
+		"completed_levels": [],
 	}
 
 
@@ -132,6 +150,19 @@ func try_to_go_to_next_level() -> void:
 		get_tree().change_scene_to_packed(level_scenes[next_level])
 
 
+
+func mark_level_complete(level_index: int) -> void:
+	unlock_level(level_index + 1)
+	if level_index not in player_state["completed_levels"]: player_state["completed_levels"].append(level_index)
+
+
+func reset_current_session_state() -> void:
+	current_session_state = {
+		"coins_collected": 0,
+		"skills_unlocked": [],
+	}
+
+
 func quit_game() -> void:
 	get_tree().quit()
 
@@ -152,9 +183,24 @@ func start_new_game() -> void:
 
 
 func continue_game() -> void:
-	# todo: load player state from save file
+	if not SaveSystem.load_game():
+		printerr("Failed to load game. Starting a new game instead.")
+		start_new_game()
+		return
 
 	if player_state["current_level"] < level_scenes.size():
 		get_tree().change_scene_to_packed(level_scenes[player_state["current_level"]])
 	else:
 		printerr("No levels unlocked to continue.")
+
+
+func on_level_complete() -> void:
+	var level_index = player_state["current_level"]
+	mark_level_complete(level_index)
+	add_coins(current_session_state["coins_collected"])
+	for skill_name in current_session_state["skills_unlocked"]:
+		unlock_skill(skill_name)
+
+	reset_current_session_state()
+	try_to_go_to_next_level()
+	SaveSystem.save_game()

scripts/ui/game_over_screen.gd

@@ -23,6 +23,7 @@ func on_restart_button_pressed() -> void:
 		return
 
 	gm.reset_player_state()
+	gm.reset_current_session_state()
 	get_tree().reload_current_scene()
 
 

scripts/ui/main_menu.gd

@@ -27,6 +27,11 @@ func _ready() -> void:
 	if version_label:
 		version_label.text = "v. " + ProjectSettings.get_setting("application/config/version")
 
+	if not SaveSystem.check_save_exists() and continue_button:
+		continue_button.disabled = true
+	else:
+		continue_button.disabled = false
+
 
 func _on_new_game_button_pressed() -> void:
 	if gm: