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

from util import spawnDaemon, splitHost
import config as conf
import stats
from hashtree import HashTree
from client import Client, Connection as ClientConnection, FailedConnection
from server import Miniserver


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)
	if os.path.isfile(args.treefile):
		treeMod=os.stat(args.treefile).st_mtime
		dataMod=os.stat(args.datafile).st_mtime
		if dataMod<treeMod and not args.force:
			print("tree file is up to date")
			return

	tree=HashTree.fromFile(args.datafile)
	tree.save(args.treefile)

def push(args):
	_checkFile(args.datafile)
	if args.tree:
		_checkFile(args.tree)
	if args.host: conf.hosts=[args.host]
	if args.port: conf.port=args.port

	c=Client(args.datafile,args.tree)
	for h in conf.hosts:
		host=splitHost(h,conf.port)
		try:
			with ClientConnection(*host) as con:
				c.setConnection(con)
				blocksToTransfer=c.negotiate()
				c.sendData(blocksToTransfer)
			print()
			print(stats.report())
		except FailedConnection: continue

def pull(args):
	_checkFile(args.datafile)
	if args.tree:
		_checkFile(args.tree)
	if args.host: conf.hosts=[args.host]
	if args.port: conf.port=args.port

	c=Client(args.datafile,args.tree)
	host=splitHost(conf.hosts[0],conf.port)
	try:
		with ClientConnection(*host) as con:
			c.setConnection(con)
			blocksToTransfer=c.negotiate()
			c.pullData(blocksToTransfer)
		print()
		print(stats.report())
	except FailedConnection: pass

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=Miniserver(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("-f","--force",action="store_true",help="force tree rebuild")
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")
pUpdate.add_argument("-t","--tree",help="stored hash tree location")
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")
pUpdate.add_argument("-t","--tree",help="stored hash tree location")
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")
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)