import os
import sys
import tempfile

from unittest import TestCase

from aws_lambda_builders.workflows.java import utils


class TestOSUtils(TestCase):
    def setUp(self):
        self.src = tempfile.mkdtemp()
        self.dst = tempfile.mkdtemp()
        self.os_utils = utils.OSUtils()

    def test_popen_runs_a_process_and_returns_outcome(self):
        cwd_py = os.path.join(os.path.dirname(__file__), "..", "..", "testdata", "cwd.py")
        p = self.os_utils.popen([sys.executable, cwd_py], stdout=self.os_utils.pipe, stderr=self.os_utils.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.os_utils.popen(
            [sys.executable, "cwd.py"], stdout=self.os_utils.pipe, stderr=self.os_utils.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_listdir(self):
        names = ["a", "b", "c"]
        for n in names:
            self.new_file(self.src, n)
        self.assertEqual(set(names), set(self.os_utils.listdir(self.src)))

    def test_copy(self):
        f = self.new_file(self.src, "a")
        expected = os.path.join(self.dst, "a")
        copy_ret = self.os_utils.copy(f, expected)
        self.assertEqual(expected, copy_ret)
        self.assertTrue("a" in os.listdir(self.dst))

    def test_exists(self):
        self.new_file(self.src, "foo")
        self.assertTrue(self.os_utils.exists(os.path.join(self.src, "foo")))

    def new_file(self, d, name):
        p = os.path.join(d, name)
        with open(p, "w") as f:
            f.close()
        return p