from msg_container import MsgContainer
from msg_sink import MsgSink
from msg_source import MsgSource
from struct import pack

class UbxPacketizer(MsgSink, MsgSource):
	def __init__(self, sync_bytes: bytes):
		MsgSink.__init__(self)
		MsgSource.__init__(self)
		self.sync_bytes = sync_bytes
		self.packet = b''
		self.wait_sync = True
		self.latency = None
	def on_recv(self, msg: MsgContainer):
		name = msg.name
		data = msg.data
		w = len(self.sync_bytes)
		self.latency = 0
		for n in range (0, len(data)):
			d = data[n:n+w]
			if d == self.sync_bytes:
				self.latency = w-1
				print("UBX-sync")
				timestamp = msg.timestamp
				self.wait_sync = False
			elif not self.wait_sync:
				if self.latency == 0:
					self.packet += d
				else:
					self.latency -= 1



	def is_msg(self, msg: MsgContainer):
		return True


if __name__ == "__main__":
	_sync = b'JA'
	_data = b'31'
	pkt = UbxPacketizer(sync_bytes=_sync)
	frame1 = _sync + b'31' + _sync + b'31'
	pkt.on_recv(MsgContainer('test', 31101970.0208, frame1))

	frame2 = _sync + b'3' + _sync + b'10'
	pkt.on_recv(MsgContainer('test', 31101970.0208, frame2))