more work on level system

autoloads/levels.gd

@@ -2,3 +2,61 @@ extends Node
 
 
 @export var level_sets: Array[LevelSet] = []
+
+
+var current_set_index: int = 0
+var current_level_index: int = 0
+
+var current_set: LevelSet:
+	get():
+		return level_sets[current_set_index]
+
+var current_level: LevelInfo:
+	get():
+		return current_set.levels[current_level_index]
+
+
+func _ready() -> void:
+	SceneManager.current_scene_changed.connect(_on_current_scene_changed)
+
+
+func get_level(set_idx: int, level_idx: int) -> LevelInfo:
+	if set_idx >= level_sets.size():
+		return null
+	var lvl_set = level_sets[set_idx]
+	if level_idx >= lvl_set.levels.size():
+		return null
+	return lvl_set.levels[level_idx]
+
+
+func advance_level() -> void:
+	var next_idx = current_level_index + 1
+	
+	# change scene to end-of-set scene if it is reached
+	if next_idx >= current_set.levels.size():
+		SceneManager.current_scene = current_set.end_scene.instantiate()
+		return
+	
+	var level_info = current_set.levels[next_idx]
+	var level = load(level_info.scene_path) as PackedScene
+	if level:
+		SceneManager.current_scene = level.instantiate()
+
+func _detect_current_level() -> void:
+	if not SceneManager.current_scene is Level:
+		current_set_index = -1
+		current_level_index = -1
+		return
+	
+	for idx_set in level_sets.size():
+		var level_set = level_sets[idx_set]
+		for idx_lvl in level_set.levels.size():
+			var level = level_set.levels[idx_lvl]
+			if level.scene_path == SceneManager.current_scene.scene_file_path:
+				current_set_index = idx_set
+				current_level_index = idx_lvl
+				return
+
+
+func _on_current_scene_changed(_new_scene: Node) -> void:
+	_detect_current_level()