import os.path
import sys
from unittest import mock

import pytest

import pre_commit.constants as C
from pre_commit.envcontext import envcontext
from pre_commit.languages import python
from pre_commit.prefix import Prefix
from pre_commit.util import make_executable
from pre_commit.util import win_exe


def test_read_pyvenv_cfg(tmpdir):
    pyvenv_cfg = tmpdir.join('pyvenv.cfg')
    pyvenv_cfg.write(
        '# I am a comment\n'
        '\n'
        'foo = bar\n'
        'version-info=123\n',
    )
    expected = {'foo': 'bar', 'version-info': '123'}
    assert python._read_pyvenv_cfg(pyvenv_cfg) == expected


def test_read_pyvenv_cfg_non_utf8(tmpdir):
    pyvenv_cfg = tmpdir.join('pyvenv_cfg')
    pyvenv_cfg.write_binary('hello = hello john.š\n'.encode())
    expected = {'hello': 'hello john.š'}
    assert python._read_pyvenv_cfg(pyvenv_cfg) == expected


def test_norm_version_expanduser():
    home = os.path.expanduser('~')
    if os.name == 'nt':  # pragma: nt cover
        path = r'~\python343'
        expected_path = fr'{home}\python343'
    else:  # pragma: nt no cover
        path = '~/.pyenv/versions/3.4.3/bin/python'
        expected_path = f'{home}/.pyenv/versions/3.4.3/bin/python'
    result = python.norm_version(path)
    assert result == expected_path


def test_norm_version_of_default_is_sys_executable():
    assert python.norm_version('default') is None


@pytest.mark.parametrize('v', ('python3.6', 'python3', 'python'))
def test_sys_executable_matches(v):
    with mock.patch.object(sys, 'version_info', (3, 6, 7)):
        assert python._sys_executable_matches(v)
        assert python.norm_version(v) is None


@pytest.mark.parametrize('v', ('notpython', 'python3.x'))
def test_sys_executable_matches_does_not_match(v):
    with mock.patch.object(sys, 'version_info', (3, 6, 7)):
        assert not python._sys_executable_matches(v)


@pytest.mark.parametrize(
    ('exe', 'realpath', 'expected'), (
        ('/usr/bin/python3', '/usr/bin/python3.7', 'python3'),
        ('/usr/bin/python', '/usr/bin/python3.7', 'python3.7'),
        ('/usr/bin/python', '/usr/bin/python', None),
        ('/usr/bin/python3.6m', '/usr/bin/python3.6m', 'python3.6m'),
        ('v/bin/python', 'v/bin/pypy', 'pypy'),
    ),
)
def test_find_by_sys_executable(exe, realpath, expected):
    with mock.patch.object(sys, 'executable', exe):
        with mock.patch.object(os.path, 'realpath', return_value=realpath):
            with mock.patch.object(python, 'find_executable', lambda x: x):
                assert python._find_by_sys_executable() == expected


@pytest.fixture
def python_dir(tmpdir):
    with tmpdir.as_cwd():
        prefix = tmpdir.join('prefix').ensure_dir()
        prefix.join('setup.py').write('import setuptools; setuptools.setup()')
        prefix = Prefix(str(prefix))
        yield prefix, tmpdir


def test_healthy_default_creator(python_dir):
    prefix, tmpdir = python_dir

    python.install_environment(prefix, C.DEFAULT, ())

    # should be healthy right after creation
    assert python.healthy(prefix, C.DEFAULT) is True

    # even if a `types.py` file exists, should still be healthy
    tmpdir.join('types.py').ensure()
    assert python.healthy(prefix, C.DEFAULT) is True


def test_healthy_venv_creator(python_dir):
    # venv creator produces slightly different pyvenv.cfg
    prefix, tmpdir = python_dir

    with envcontext((('VIRTUALENV_CREATOR', 'venv'),)):
        python.install_environment(prefix, C.DEFAULT, ())

    assert python.healthy(prefix, C.DEFAULT) is True


def test_unhealthy_python_goes_missing(python_dir):
    prefix, tmpdir = python_dir

    python.install_environment(prefix, C.DEFAULT, ())

    exe_name = win_exe('python')
    py_exe = prefix.path(python.bin_dir('py_env-default'), exe_name)
    os.remove(py_exe)

    assert python.healthy(prefix, C.DEFAULT) is False


def test_unhealthy_with_version_change(python_dir):
    prefix, tmpdir = python_dir

    python.install_environment(prefix, C.DEFAULT, ())

    with open(prefix.path('py_env-default/pyvenv.cfg'), 'w') as f:
        f.write('version_info = 1.2.3\n')

    assert python.healthy(prefix, C.DEFAULT) is False


def test_unhealthy_system_version_changes(python_dir):
    prefix, tmpdir = python_dir

    python.install_environment(prefix, C.DEFAULT, ())

    with open(prefix.path('py_env-default/pyvenv.cfg'), 'a') as f:
        f.write('base-executable = /does/not/exist\n')

    assert python.healthy(prefix, C.DEFAULT) is False


def test_unhealthy_old_virtualenv(python_dir):
    prefix, tmpdir = python_dir

    python.install_environment(prefix, C.DEFAULT, ())

    # simulate "old" virtualenv by deleting this file
    os.remove(prefix.path('py_env-default/pyvenv.cfg'))

    assert python.healthy(prefix, C.DEFAULT) is False


def test_unhealthy_then_replaced(python_dir):
    prefix, tmpdir = python_dir

    python.install_environment(prefix, C.DEFAULT, ())

    # simulate an exe which returns an old version
    exe_name = win_exe('python')
    py_exe = prefix.path(python.bin_dir('py_env-default'), exe_name)
    os.rename(py_exe, f'{py_exe}.tmp')

    with open(py_exe, 'w') as f:
        f.write('#!/usr/bin/env bash\necho 1.2.3\n')
    make_executable(py_exe)

    # should be unhealthy due to version mismatch
    assert python.healthy(prefix, C.DEFAULT) is False

    # now put the exe back and it should be healthy again
    os.replace(f'{py_exe}.tmp', py_exe)

    assert python.healthy(prefix, C.DEFAULT) is True