# coding: utf-8
from __future__ import print_function, division, absolute_import

import os.path
import subprocess
import sys
from contextlib import contextmanager
from shutil import rmtree
from tempfile import mkdtemp

from cutadapt.__main__ import main


@contextmanager
def redirect_stderr():
	"""Send stderr to stdout. Nose doesn't capture stderr, yet."""
	old_stderr = sys.stderr
	sys.stderr = sys.stdout
	yield
	sys.stderr = old_stderr


@contextmanager
def temporary_path(name):
	tempdir = mkdtemp(prefix='cutadapt-tests.')
	path = os.path.join(tempdir, name)
	try:
		yield path
	finally:
		rmtree(tempdir)


def datapath(path):
	return os.path.join(os.path.dirname(__file__), 'data', path)


def cutpath(path):
	return os.path.join(os.path.dirname(__file__), 'cut', path)


class FilesDifferent(Exception):
	pass


def assert_files_equal(path1, path2):
	try:
		subprocess.check_output(['diff', '-u', path1, path2], stderr=subprocess.STDOUT)
	except subprocess.CalledProcessError as e:
		raise FilesDifferent('\n' + e.output.decode())  # TODO add "from None"
	except AttributeError:  # Python 2.6 does not have check_output
		assert subprocess.call(['diff', '-u', path1, path2]) == 0


def run(params, expected, inpath, inpath2=None):
	if type(params) is str:
		params = params.split()
	with temporary_path(expected) as tmp_fastaq:
		params += ['-o', tmp_fastaq]  # TODO not parallelizable
		params += [datapath(inpath)]
		if inpath2:
			params += [datapath(inpath2)]
		assert main(params) is None
		# TODO redirect standard output
		assert_files_equal(cutpath(expected), tmp_fastaq)
	# TODO diff log files