import sys
import os.path
import logging as log
from argparse import ArgumentParser

from util import spawnDaemon
import config as conf
import stats
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 push(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)
	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

	c=Client(args.datafile)
	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)
	if args.port: conf.port=args.port

	s=Server(args.datafile,args.tree)
	try:
		spawnDaemon(s.serve)
	except Exception as e:
		log.exception("exception: %s",e)


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)