import collections

import socket

import ssl

import logging as log

from datetime import datetime

import config as conf

import stats

from util import Progress

from networkers import NetworkReader,NetworkWriter

class Connection:

	def __init__(self):

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

		sslContext=ssl.create_default_context(cafile=conf.peers)

		sslContext.check_hostname=False

		sslContext.load_cert_chain(conf.certfile,conf.keyfile)

		self._socket=sslContext.wrap_socket(sock)

		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.shutdown(socket.SHUT_RDWR)

		self._socket.close()

class Client:

		self._incoming=None

		self._outcoming=None

		self._filename=filename

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

	## Asks server for node hashes to determine which are to be transferred.

	#

	# Uses a binary HashTree, where item at k is hash of items at 2k+1, 2k+2.

	#

	# Requests nodes in order of a batch DFS. Needs stack of size O(treeDepth*batchSize). Nodes in each tree level are accessed in order.

	def negotiate(self):

		blocksToTransfer=[]

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

		# initialize session

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

		self._outcoming.writeMsg(jsonData)

		jsonData,binData=self._incoming.readMsg()

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

		# determine which blocks to send

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

		progress=Progress(localTree.leafCount)

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

		progress=Progress(len(blocksToTransfer))

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

			self._outcoming.writeMsg({"command":"req", "index":i2, "dataType":"data"})

			jsonData,binData=self._incoming.readMsg()

			assert jsonData["command"]=="send" and jsonData["index"]==i2 and jsonData["dataType"]=="data", jsonData

			if i1+1!=i2:

				dataFile.seek(i2*HashTree.BLOCK_SIZE)

			dataFile.write(binData)

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

			stats.logTransferredBlock()

			i1=i2

			progress.p(k)

		progress.done()

		self._outcoming.writeMsg({"command":"end"})

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

		dataFile.close()

	def setConnection(self,connection):

		(self._incoming,self._outcoming)=connection

import hashlib

import os

from datetime import datetime

from util import Progress

class HashTree:

	HASH_LEN=16 # bytes

	BLOCK_SIZE=4096 # bytes

	## Prepares a tree containing leafCount leaves.

	def __init__(self,leafCount):

		self.store=[b""]*(leafCount*2-1)

		self.leafStart=leafCount-1

		self.leafCount=leafCount

		self._index=self.leafStart

	@classmethod

	def fromFile(cls,filename):

		with open(filename,"rb") as f:

			stat=os.fstat(f.fileno())

			size=stat.st_size # !! symlinks

			leafCount=(size-1)//HashTree.BLOCK_SIZE+1 # number of leaf blocks

			res=cls(leafCount)

			print(datetime.now(), "hashing file:")

			progress=Progress(leafCount)

			for i in range(leafCount):

				data=f.read(HashTree.BLOCK_SIZE)

				progress.p(i)

			progress.done()

		res.buildTree()

		return res

	@classmethod

	def load(cls,filename):

		with open(filename,"rb") as f:

			stat=os.fstat(f.fileno())

			size=stat.st_size

		self._index+=1

	## Updates a hash stored in the leaf.

	def updateLeaf(self,index,h):

		if index<self.leafStart: raise IndexError()

		self.store[index]=h

		self.updateNode((index-1)//2)

	## Updates the node at index and all its ancestors.

	def updateNode(self,index):

		while index>=0:

			index=(index-1)//2

	## Fast construction of the tree over the leaves. O(n).

	def buildTree(self):

		print(datetime.now(), "building tree:")

		progress=Progress(-1, self.leafStart-1)

		for i in range(self.leafStart-1,-1,-1):

			progress.p(i)

		progress.done()

		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 push(args):

	_checkFile(args.datafile)

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

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

	with ClientConnection() as con:

		c.setConnection(con)

		blocksToTransfer=c.negotiate()

		c.sendData(blocksToTransfer)

	print()

	print(stats.report())

def pull(args):

	_checkFile(args.datafile)

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

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

	with ClientConnection() as con:

		c.setConnection(con)

		blocksToTransfer=c.negotiate()

		c.pullData(blocksToTransfer)

	print()

	print(stats.report())

def serve(args):

	_checkFile(args.datafile)

	if args.tree:

		_checkFile(args.tree)

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

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("push")

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

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

pUpdate.add_argument("datafile")

pUpdate.set_defaults(func=push)

pUpdate=subparsers.add_parser("pull")

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

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

pUpdate.add_argument("datafile")

pUpdate.set_defaults(func=pull)

pServe=subparsers.add_parser("serve")

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

pServe.add_argument("--host",default="")

pServe.add_argument("-t","--tree",help="stored hash tree location")

pServe.add_argument("datafile")

pServe.set_defaults(func=serve)

args=parser.parse_args()

args.func(args)

import ssl

import multiprocessing

import logging as log

from networkers import NetworkReader,NetworkWriter

import config as conf

class Connection:

	def __init__(self,serverSocket,sslContext):

		sock, address = serverSocket.accept()

		self._socket=sslContext.wrap_socket(sock,server_side=True)

		log.info('Connected by {0}'.format(address))

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

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

		return (jsonResponse,binResponse)

	def _receiveData(self,jsonData,binData):

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

		i=jsonData["index"]

		if self._lastIndex+1!=i:

			self._dataFile.seek(i*self.BLOCK_SIZE)

		self._dataFile.write(binData)

		self._lastIndex=i

		if self._treeFile:

		return ({"command": "ack", "index": i},)

	def _finalize(self):

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

		self._dataFile.close()

		self._dataFileHandle=None

		if self._treeFile:

			log.info("updating hash tree...")

			for (k,v) in self._newLeaves.items():

				self._tree.updateLeaf(k, v)

			self._tree.save(self._treeFile)