import os
import shutil
import sys
import tempfile

from unittest import TestCase

from aws_lambda_builders.workflows.nodejs_npm import utils


class TestOSUtils(TestCase):
    def setUp(self):
        self.osutils = utils.OSUtils()

    def test_copy_file_copies_existing_file_into_a_dir(self):
        test_file = os.path.join(os.path.dirname(__file__), "test_data", "test.tgz")

        test_dir = tempfile.mkdtemp()

        self.osutils.copy_file(test_file, test_dir)

        output_files = set(os.listdir(test_dir))

        shutil.rmtree(test_dir)

        self.assertEqual({"test.tgz"}, output_files)

    def test_copy_file_copies_existing_file_into_a_file(self):
        test_file = os.path.join(os.path.dirname(__file__), "test_data", "test.tgz")

        test_dir = tempfile.mkdtemp()

        self.osutils.copy_file(test_file, os.path.join(test_dir, "copied_test.tgz"))

        output_files = set(os.listdir(test_dir))

        shutil.rmtree(test_dir)

        self.assertEqual({"copied_test.tgz"}, output_files)

    def test_remove_file_removes_existing_file(self):
        test_file = os.path.join(os.path.dirname(__file__), "test_data", "test.tgz")

        test_dir = tempfile.mkdtemp()

        copied_file = os.path.join(test_dir, "copied_test.tgz")

        shutil.copy(test_file, copied_file)

        self.osutils.remove_file(copied_file)

        self.assertFalse(os.path.isfile(copied_file))

    def test_file_exists_checking_if_file_exists_in_a_dir(self):
        existing_file = os.path.join(os.path.dirname(__file__), "test_data", "test.tgz")

        nonexisting_file = os.path.join(os.path.dirname(__file__), "test_data", "nonexisting.tgz")

        self.assertTrue(self.osutils.file_exists(existing_file))

        self.assertFalse(self.osutils.file_exists(nonexisting_file))

    def test_dirname_returns_directory_for_path(self):
        dirname = self.osutils.dirname(sys.executable)

        self.assertEqual(dirname, os.path.dirname(sys.executable))

    def test_abspath_returns_absolute_path(self):
        result = self.osutils.abspath(".")

        self.assertTrue(os.path.isabs(result))

        self.assertEqual(result, os.path.abspath("."))

    def test_joinpath_joins_path_components(self):
        result = self.osutils.joinpath("a", "b", "c")

        self.assertEqual(result, os.path.join("a", "b", "c"))

    def test_popen_runs_a_process_and_returns_outcome(self):
        cwd_py = os.path.join(os.path.dirname(__file__), "..", "..", "testdata", "cwd.py")

        p = self.osutils.popen([sys.executable, cwd_py], stdout=self.osutils.pipe, stderr=self.osutils.pipe)

        out, err = p.communicate()

        self.assertEqual(p.returncode, 0)

        self.assertEqual(out.decode("utf8").strip(), os.getcwd())

    def test_popen_can_accept_cwd(self):
        testdata_dir = os.path.join(os.path.dirname(__file__), "..", "..", "testdata")

        p = self.osutils.popen(
            [sys.executable, "cwd.py"], stdout=self.osutils.pipe, stderr=self.osutils.pipe, cwd=testdata_dir
        )

        out, err = p.communicate()

        self.assertEqual(p.returncode, 0)

        self.assertEqual(out.decode("utf8").strip(), os.path.abspath(testdata_dir))

    def test_parse_json_reads_json_contents_into_memory(self):
        json_file = os.path.join(os.path.dirname(__file__), "test_data", "test.json")
        json_contents = self.osutils.parse_json(json_file)
        self.assertEqual(json_contents["a"], 1)
        self.assertEqual(json_contents["b"]["c"], 2)