# Copyright (C) 2014 Intra2net AG
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published
# by the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see
# <http://www.gnu.org/licenses/lgpl-3.0.html>

# Authors: Victor Ramirez de la Corte <virako@wadobo.com>
#          Eduardo Robles Elvira <edulix@wadobo.com>

import os
import shutil
import sys
import hashlib
import unittest
from . import run_benchmark
from . import create_pseudo_random_files

DEFAULTS_COMPRESS_LEVEL_TEST = (int(42 / 10), 42, 42, 1, 8)

class CompressLevelTest(unittest.TestCase):
    """
    Small integration test that uses create_pseudo_random_files to create a
    deterministic files and directories tree and then uses delta-tar with the
    run_benchmark script.
    """

    BUF_SIZE = 2**12

    def __init__(self, num_dir=None, num_files=None, size=None,
                 compression_lvl_1=None, compression_lvl_2=None):
        if isinstance (num_dir, str) and \
           num_files         is None and \
           size              is None and \
           compression_lvl_1 is None and \
           compression_lvl_2 is None:
            # invoked as module
            num_dir           = DEFAULTS_COMPRESS_LEVEL_TEST [0]
            num_files         = DEFAULTS_COMPRESS_LEVEL_TEST [1]
            size              = DEFAULTS_COMPRESS_LEVEL_TEST [2]
            compression_lvl_1 = DEFAULTS_COMPRESS_LEVEL_TEST [3]
            compression_lvl_2 = DEFAULTS_COMPRESS_LEVEL_TEST [4]
        elif num_dir           is None or \
             num_files         is None or \
             size              is None or \
             compression_lvl_1 is None or \
             compression_lvl_2 is None:
            raise ValueError
        super(CompressLevelTest, self).__init__('test_compression_level')
        self.num_dir = num_dir
        self.num_files = num_files
        self.size = size
        self.compression_lvl_1 = compression_lvl_1
        self.compression_lvl_2 = compression_lvl_2

    def setUp(self):
        '''
        Create pseudo random test files
        '''
        shutil.rmtree("source_dir", ignore_errors=True)
        args = ['--nfile', str(self.num_files),
                '--ndir', str(self.num_dir),
                '--size', str(self.size),
                '--path', 'source_dir',
                '--seed', '1337']
        self.seed = create_pseudo_random_files.main(args)

    def tearDown(self):
        '''
        Remove pseudo random files created by unit tests
        '''
        shutil.rmtree("source_dir", ignore_errors=True)

    def test_compression_level(self):
        '''
        Create two test compression with two different compression level.
        '''
        args = ['--test', 'delta-tarfile',
                '-l', str(self.compression_lvl_1),
                '-p', 'source_dir']
        run_benchmark.main(args)
        size1 = os.path.getsize('test_tarfile.tar.gz')
        os.unlink('test_tarfile.tar.gz')

        args = ['--test', 'delta-tarfile',
                '-l', str(self.compression_lvl_2),
                '-p', 'source_dir']
        run_benchmark.main(args)
        size2 = os.path.getsize('test_tarfile.tar.gz')
        os.unlink('test_tarfile.tar.gz')

        self.assertGreater(size1, size2, msg="""Fail test using lvl %d and
                lvl %d, with the seed: %d. """ % (self.compression_lvl_1,
                    self.compression_lvl_2, self.seed))


def suite():
    suite = unittest.TestSuite()
    for size in (10, ):
        suite.addTest(CompressLevelTest(int(size / 10), size, size, 1, 8))
    return suite