Bunch of changes

data_recorder_node.gd

@@ -0,0 +1,95 @@
+extends Node
+class_name DataRecorderNode
+
+var MAX_SENSOR_DATA_SIZE = 524288000
+
+var cached_data = []
+
+var thread: Thread
+var mutex: Mutex
+var exit_thread = false
+
+var timer = 0
+var timer_target = 15
+
+var target_dir = "user://sensor_data/"
+
+# Called when the node enters the scene tree for the first time.
+func _ready() -> void:
+	DataSignals.raw_data_received.connect(_on_raw_data_received)
+	thread = Thread.new()
+	mutex = Mutex.new()
+	thread.start(_thread_func)
+	DirAccess.make_dir_absolute(target_dir)
+
+func _exit_tree() -> void:
+	mutex.lock()
+	exit_thread = true
+	mutex.unlock()
+	thread.wait_to_finish()
+
+func _process(delta: float) -> void:
+	mutex.lock()
+	timer += delta
+	mutex.unlock()
+
+func _on_raw_data_received(source_ip: String, data_type: String, timestamp_list: Array, data_dict: Dictionary):
+	cached_data.append([source_ip, data_type, timestamp_list, data_dict])
+
+func _thread_func():
+	while true:
+		mutex.lock()
+		var should_exit = exit_thread
+		mutex.unlock()
+		if should_exit:
+			break
+		mutex.lock()
+		var should_write_data = (timer >= timer_target)
+		mutex.unlock()
+		if not should_write_data:
+			continue
+		mutex.lock()
+		timer = 0
+		var data_copy = null
+		if cached_data.size() > 0:
+			data_copy = cached_data.duplicate(true)
+			cached_data.clear()
+		mutex.unlock()
+		if data_copy != null:
+			_write_data(data_copy)
+		_delete_old_data()
+
+func _write_data(data_to_write: Array):
+	var current_file_path = target_dir + str(Time.get_unix_time_from_system()) + "_sensor_data.csv"
+	var file = FileAccess.open(current_file_path, FileAccess.WRITE)
+	for data in data_to_write:
+		var line = str(data[0]) + ',' + str(data[1]) + ','
+		for time_data in data[2]:
+			line += str(time_data) + ','
+		for value in data[3]:
+			line += str(value) + ','
+		file.store_line(line)
+	file.close()
+	
+func _delete_old_data():
+	var files: Array = []
+	var dir = DirAccess.open(target_dir)
+	dir.list_dir_begin()
+	while true:
+		var file_name = dir.get_next()
+		if file_name == "":
+			break
+		elif file_name.begins_with("."):
+			continue
+		files.append(file_name)
+	dir.list_dir_end()
+	files.sort()
+	var cutoff_idx = 0
+	var file_size_sum = 0
+	for idx in range(files.size(), 0, -1):
+		file_size_sum += FileAccess.get_size(target_dir + files[idx-1])
+		if file_size_sum >= MAX_SENSOR_DATA_SIZE:
+			cutoff_idx = idx
+	for i in range(cutoff_idx):
+		DirAccess.remove_absolute(target_dir+files[i])
+