from datetime import datetime

import config as conf

from hashtree import HashTree

from networkers import NetworkReader,NetworkWriter

			# determine which blocks to send

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

			while len(nodeStack)>0:

				i=nodeStack.pop()

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

						nodeStack.append(2*i+1)

					else:

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

		return blocksToTransfer

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

		with Connection() as (incoming,outcoming):

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

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

				if i1+1!=i2:

				jsonData,binData=incoming.readMsg()

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

				i1=i2

		with Connection() as (incoming,outcoming):

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

import os

from datetime import datetime

class HashTree:

			res=cls(leafCount)

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

			for i in range(leafCount):

				data=f.read(HashTree.BLOCK_SIZE)

				res.insertLeaf(hashlib.sha256(data).digest()[HashTree.HASH_LEN:])

		res.buildTree()

		return res

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

	def buildTree(self):

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

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

			self.store[i]=hashlib.sha256(self.store[i*2+1]+self.store[i*2+2]).digest()[HashTree.HASH_LEN:]

if __name__=="__main__":