import json


class NetworkReader:
	def __init__(self,stream):
		self.stream=stream

	def readMsg(self):
		data=self.stream.readline()
		assert data
		jsonLength=int(data.split(b":")[1].strip()) # "json-length: length" -> length
		data=self.stream.readline()
		assert data
		binLength=int(data.split(b":")[1].strip()) # "bin-length: length" -> length
		jsonData=self.stream.read(jsonLength)
		assert len(jsonData)==jsonLength
		jsonData=json.loads(str(jsonData,encoding="utf-8"))
		binData=self.stream.read(binLength)
		assert len(binData)==binLength
		
		return (jsonData,binData)
		

class NetworkWriter:
	def __init__(self,stream):
		self.stream=stream

	def writeMsg(self,*args):
		self.stream.write(self.prepMsg(*args))
		self.stream.flush()

	def prepMsg(self,jsonData,binData=b""):
		jsonData=bytes(json.dumps(jsonData)+"\n",encoding="utf-8")
		jsonLength=bytes("json-length: "+str(len(jsonData))+"\n",encoding="utf-8")
		binLength=bytes("bin-length: "+str(len(binData))+"\n",encoding="utf-8")

		return b"".join((jsonLength,binLength,jsonData,binData))