import collections

import socket

import logging as log

from datetime import datetime

import config as conf

from util import Progress

from hashtree import HashTree

from networkers import NetworkReader,NetworkWriter

class Connection:

	def __init__(self):

		self.socket=socket.socket(socket.AF_INET,socket.SOCK_STREAM)

		self.socket.connect((conf.hosts[0], conf.port))

		fr=self.socket.makefile(mode="rb")

		fw=self.socket.makefile(mode="wb")

		self.incoming=NetworkReader(fr)

		self.outcoming=NetworkWriter(fw)

	def __enter__(self):

		return self.incoming,self.outcoming

	def __exit__(self, exc_type, exc_val, exc_tb):

		self.socket.close()

class Client:

	def __init__(self,filename):

	def negotiate(self):

		print(datetime.now(), "initializing...")

		localTree=HashTree.fromFile(self.filename)

		blocksToTransfer=[]

		nodeStack=collections.deque([0]) # root

		# initialize session

		with Connection() as (incoming,outcoming):

			jsonData={"command":"init", "blockSize":localTree.BLOCK_SIZE, "blockCount":localTree.leafCount, "version":conf.version}

			outcoming.writeMsg(jsonData)

			jsonData,binData=incoming.readMsg()

			assert jsonData["command"]=="ack"

			# determine which blocks to send

			print(datetime.now(), "negotiating:")

			progress=Progress(localTree.leafCount)

			while len(nodeStack)>0:

				i=nodeStack.pop()

				outcoming.writeMsg({"command":"req", "index":i})

				jsonData,binData=incoming.readMsg()

				assert jsonData["index"]==i

				assert jsonData["dataType"]=="hash"

				if localTree.store[i]!=binData:

					if 2*i+3<len(localTree.store): # inner node

						nodeStack.append(2*i+2)

						nodeStack.append(2*i+1)

					else:

						blocksToTransfer.append(i-localTree.leafStart) # leaf

						progress.p(i-localTree.leafStart)

		progress.done()

		return blocksToTransfer

	def sendData(self,blocksToTransfer):

		log.info(blocksToTransfer)

		dataFile=open(self.filename,mode="rb")

		i1=-1

		print(datetime.now(), "sending data:")

		with Connection() as (incoming,outcoming):

			progress=Progress(len(blocksToTransfer))

			for (k,i2) in enumerate(blocksToTransfer):

				jsonData={"command":"send", "index":i2, "dataType":"data"}

				if i1+1!=i2:

					dataFile.seek(i2*HashTree.BLOCK_SIZE)

				binData=dataFile.read(HashTree.BLOCK_SIZE)

				log.info("block #{0}: {1}...{2}".format(i2,binData[:5],binData[-5:]))

				outcoming.writeMsg(jsonData,binData)

				jsonData,binData=incoming.readMsg()

				assert jsonData["command"]=="ack" and jsonData["index"]==i2, jsonData

				i1=i2

				progress.p(k)

		progress.done()

		with Connection() as (incoming,outcoming):

			outcoming.writeMsg({"command":"end"})

		log.info("closing session...")

		dataFile.close()

import sys

import os.path

from argparse import ArgumentParser

import config as conf

from hashtree import HashTree

from client import Client

from server import Server

def _checkFile(f):

	if not os.path.isfile(f):

		print("invalid file specified:",f,file=sys.stderr)

		sys.exit(1)

def buildTree(args):

	_checkFile(args.datafile)

	tree=HashTree.fromFile(args.datafile)

	tree.save(args.treefile)

def update(args):

	_checkFile(args.datafile)

	if args.host: conf.hosts.insert(0,args.host)

	if args.port: conf.port=args.port

	c=Client(args.datafile)

	blocksToTransfer=c.negotiate()

	c.sendData(blocksToTransfer)

def serve(args):

	_checkFile(args.datafile)

	if args.tree:

		_checkFile(args.tree)

	if args.host: conf.hosts.insert(0,args.host)

	if args.port: conf.port=args.port

	s=Server(args.datafile,args.tree)

	s.serve()

parser=ArgumentParser()

subparsers=parser.add_subparsers()

pBuild=subparsers.add_parser("build")

pBuild.add_argument("treefile", help="stored hash tree location")

pBuild.add_argument("datafile")

pBuild.set_defaults(func=buildTree)

pUpdate=subparsers.add_parser("update")

pUpdate.add_argument("-p","--port",type=int)

pUpdate.add_argument("--host",default="127.0.0.1")

pUpdate.add_argument("datafile")

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.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))