import os
import shutil
import hashlib
import multiprocessing
from logging import FileHandler
from unittest import TestCase

import config
from hashtree import HashTree
from client import Client, Connection as ClientConnection, DeniedConnection
from server import Miniserver
from . import RedirectedOutput


config.logger.removeHandler(config.handler)
handler = FileHandler("/tmp/morevna.log")
handler.setFormatter(config.formatter)
config.logger.addHandler(handler)

config.batch_size.hash = 8
config.batch_size.data = 8

data_dir = os.path.join(config.directory, "src/tests/data")
filename = os.path.join(data_dir, "test.img")


def compare_files(f1, f2):
	with open(f1, mode="rb") as f:
		h2 = hashlib.sha256(f.read()).hexdigest()
	with open(f2, mode="rb") as f:
		h = hashlib.sha256(f.read()).hexdigest()
	return (h, h2)


class TestMorevna(RedirectedOutput, TestCase):
	_stdout = None

	def setUp(self):
		src = os.path.join(data_dir, "test1.img")
		shutil.copyfile(src, filename)

	@classmethod
	def tearDownClass(cls):
		super().tearDownClass()
		os.remove(filename)

	def test_build(self):
		tree_file = os.path.join(data_dir, "test.bin")
		ref_file = os.path.join(data_dir, "test1.bin")

		tree = HashTree.from_file(os.path.join(data_dir, "test1.img"))
		tree.save(tree_file)

		self.assertEqual(*compare_files(ref_file, tree_file))

		os.remove(tree_file)

	def test_push(self):
		config.port += 1
		ms = Miniserver(filename)
		p = multiprocessing.Process(target=ms.serve)
		p.start()

		for client_file in ("test2.img", "test3.img", "test4.img"):
			client_file = os.path.join(data_dir, client_file)
			c = Client(client_file)
			with ClientConnection("127.0.0.1", config.port) as con:
				c.set_connection(con)
				c.init("push")
				blocks_to_transfer = c.negotiate()
				c.send_data(blocks_to_transfer)

			self.assertEqual(*compare_files(client_file, filename))

		p.terminate()
		p.join()

	def test_pull(self):
		config.port += 1
		server_file = os.path.join(data_dir, "test3.img")
		ms = Miniserver(server_file)
		p = multiprocessing.Process(target=ms.serve)
		p.start()

		c = Client(filename)
		with ClientConnection("127.0.0.1", config.port) as con:
			c.set_connection(con)
			c.init("pull")
			blocks_to_transfer = c.negotiate()
			c.pull_data(blocks_to_transfer)

		self.assertEqual(*compare_files(server_file, filename))

		p.terminate()
		p.join()

	def test_deny(self):
		config.port += 1
		ms = Miniserver(filename)
		p = multiprocessing.Process(target=ms.serve)
		p.start()

		c1 = Client(os.path.join(data_dir, "test2.img"))
		with ClientConnection("127.0.0.1", config.port) as con1:
			c1.set_connection(con1)
			c1.init("push")

			c2 = Client(os.path.join(data_dir, "test3.img"))
			with ClientConnection("127.0.0.1", config.port) as con2:
				c2.set_connection(con2)
				with self.assertRaises(DeniedConnection):
					c2.init("push")
			c1.send_data([]) # to unlock the server

		p.terminate()
		p.join()