from pathlib import Path

import importlib.metadata

import pytest

import yaml

from pyproject_buildrequires import generate_requires

testcases = {}

with Path(__file__).parent.joinpath('pyproject_buildrequires_testcases.yaml').open() as f:

    testcases = yaml.safe_load(f)

@pytest.mark.parametrize('case_name', testcases)

def test_data(case_name, capsys, tmp_path, monkeypatch):

    case = testcases[case_name]

    cwd = tmp_path.joinpath('cwd')

    cwd.mkdir()

    monkeypatch.chdir(cwd)

    if case.get('xfail'):

        pytest.xfail(case.get('xfail'))

    for filename in case:

        file_types = ('.toml', '.py', '.in', '.ini', '.txt')

        if filename.endswith(file_types):

            cwd.joinpath(filename).write_text(case[filename])

    for name, value in case.get('environ', {}).items():

        monkeypatch.setenv(name, value)

    def get_installed_version(dist_name):

        try:

            return str(case['installed'][dist_name])

        except (KeyError, TypeError):

            raise importlib.metadata.PackageNotFoundError(

                f'info not found for {dist_name}'

            )

    requirement_files = case.get('requirement_files', [])

    requirement_files = [open(f) for f in requirement_files]

    try:

        generate_requires(

            get_installed_version=get_installed_version,

            include_runtime=case.get('include_runtime', False),

            extras=case.get('extras', []),

            toxenv=case.get('toxenv', None),

            generate_extras=case.get('generate_extras', False),

            requirement_files=requirement_files,

            use_build_system=case.get('use_build_system', True),

        )

    except SystemExit as e:

        assert e.code == case['result']

    except Exception as e:

        if 'except' not in case:

            raise

        assert type(e).__name__ == case['except']

    else:

        assert 0 == case['result']

        # this prevents us from accidentally writing "empty" tests

        # if we ever need to do that, we can remove the check or change it:

        assert 'expected' in case or 'stderr_contains' in case

        out, err = capsys.readouterr()

        if 'expected' in case:

            assert out == case['expected']

        # stderr_contains may be a string or list of strings

        stderr_contains = case.get('stderr_contains')

        if stderr_contains is not None:

            if isinstance(stderr_contains, str):

                stderr_contains = [stderr_contains]

            for expected_substring in stderr_contains:

                assert expected_substring in err

    finally:

        for req in requirement_files:

            req.close()