from __future__ import annotations

import datetime
from importlib.metadata import distribution
import json
from pathlib import Path
import re
import subprocess
import sys
from types import SimpleNamespace
from typing import TYPE_CHECKING

from bs4 import BeautifulSoup
import numpy as np
import pytest

import scooby

if TYPE_CHECKING:
    from pytest_console_scripts import ScriptRunner

# Write a package `dummy_module` without version number.
ppath = Path('tests') / 'dummy_module'
ppath.mkdir(exist_ok=True)

with (ppath / '__init__.py').open('w') as f:
    f.write("info = 'Package without __version__ number.'\n")

sys.path.append('tests')


def test_report() -> None:
    report = scooby.Report()
    text = str(report)
    assert len(text) > 0
    assert len(report.packages) > 0
    for pkg, vers in report.packages.items():
        assert isinstance(pkg, str)
        assert isinstance(vers, str)
    report = scooby.Report(core='numpy')
    assert 'numpy' in report.packages
    html = report._repr_html_()
    assert len(html) > 0
    # Same as what is printed in Travis build log
    report = scooby.Report(additional=['pytest', 'foo'])
    report = scooby.Report(
        additional=[
            'foo',
        ],
    )
    report = scooby.Report(
        additional=[
            pytest,
        ],
    )
    report = scooby.Report(additional=pytest)
    report = scooby.Report(additional=['collections', 'foo', 'aaa'], sort=True)


def test_timezone(monkeypatch: pytest.MonkeyPatch) -> None:
    # Patch datetime to simulate non-UTC system time
    class FixedDatetime(datetime.datetime):
        @classmethod
        def now(cls, _tz: datetime.timezone | None = None) -> None:
            # Return a fixed time in, e.g., US/Eastern (UTC-5)
            return datetime.datetime(
                2025,
                1,
                1,
                12,
                0,
                0,
                tzinfo=datetime.timezone(datetime.timedelta(hours=-5)),
            )

    monkeypatch.setattr(datetime, 'datetime', FixedDatetime)
    assert 'UTC' in str(scooby.Report())


# Global fake packages dict
FAKE_INSTALLED_PACKAGES = {
    'numpy': '1.27.0',
    'scipy': '1.12.0',
    'misc_pkg1': '0.1',
    'misc_pkg2': '0.2',
}


def fake_distributions() -> None:
    """Yield fake Distribution-like objects from the global dict."""
    for name, version in FAKE_INSTALLED_PACKAGES.items():
        yield SimpleNamespace(metadata={'Name': name, 'Version': version})


def test_dict(monkeypatch: pytest.MonkeyPatch) -> None:
    # Patch distributions to return fake installed packages
    monkeypatch.setattr('importlib.metadata.distributions', fake_distributions)
    report = scooby.Report(['no_version', 'does_not_exist'], show_other=True)
    report_repr = repr(report)

    # Test regular dict items separately from other items
    report_dict = report.to_dict()
    assert 'other' in report_dict
    other = report_dict.pop('other')

    for key, value in report_dict.items():
        if key != 'MKL':
            assert key in report_repr
        assert value[:10] in report_repr

    # Test other items (converted from JSON)
    other_dict = json.loads(other)
    for key in other_dict:
        assert key in report_repr


def test_inheritence_example() -> None:
    class Report(scooby.Report):
        def __init__(
            self,
            additional: list[str] | None = None,
            ncol: int = 3,
            text_width: int = 80,
            sort: bool = False,
        ) -> None:
            """Initiate a scooby.Report instance."""
            # Mandatory packages.
            core = ['psutil', 'mkl', 'numpy', 'scooby']

            # Optional packages.
            optional = [
                'your_optional_packages',
                'e.g.',
                'matplotlib',
                'foo',
            ]

            scooby.Report.__init__(
                self,
                additional=additional,
                core=core,
                optional=optional,
                ncol=ncol,
                text_width=text_width,
                sort=sort,
            )

    report = Report(['pytest'])
    assert 'psutil' in report.packages
    assert 'mkl' in report.packages
    assert 'numpy' in report.packages


def test_ipy() -> None:
    scooby.in_ipykernel()


def test_get_version() -> None:
    name, version = scooby.get_version(np)
    assert version == np.__version__
    assert name == 'numpy'

    # Package that was no version given by owner; gets 0.1.0 from setup/pip
    name, version = scooby.get_version('no_version')
    assert version == '0.1.0'
    assert name == 'no_version'

    # Dummy module without version (not installed properly)
    name, version = scooby.get_version('dummy_module')
    assert version == scooby.report.VERSION_NOT_FOUND
    assert name == 'dummy_module'

    name, version = scooby.get_version('does_not_exist')
    assert version == scooby.report.MODULE_NOT_FOUND
    assert name == 'does_not_exist'


def test_plain_vs_html() -> None:
    report = scooby.Report()
    text_html = BeautifulSoup(report._repr_html_(), features='html.parser').get_text()
    text_plain = report.__repr__()

    text_plain = ' '.join(re.findall('[a-zA-Z1-9]+', text_plain))
    text_html = ' '.join(re.findall('[a-zA-Z1-9]+', text_html))

    # Plain text currently starts with `Date :`;
    # we should remove that, or add it to the html version too.
    assert text_html[20:].strip() == text_plain[25:].strip()


def test_extra_meta() -> None:
    report = scooby.Report(extra_meta=('key', 'value'))
    assert 'key : value' in report.__repr__()
    report = scooby.Report(extra_meta=(('key', 'value'),))
    assert 'key : value' in report.__repr__()
    report = scooby.Report(extra_meta=(('key', 'value'), ('another', 'one')))
    assert 'key : value' in report.__repr__()
    assert 'another : one' in report.__repr__()
    with pytest.raises(TypeError):
        report = scooby.Report(extra_meta=(('key', 'value'), 'foo'))
    with pytest.raises(TypeError):
        report = scooby.Report(extra_meta='foo')
    with pytest.raises(TypeError):
        report = scooby.Report(extra_meta='for')


@pytest.mark.skipif(sys.version_info.major < 3, reason='Tracking not supported on Python 2.')
def test_tracking() -> None:
    scooby.track_imports()
    # import a float value which should not be tracked
    from scipy.constants import mu_0  # noqa: F401

    report = scooby.TrackedReport()
    scooby.untrack_imports()
    import dummy_module  # noqa: F401
    import no_version  # noqa: F401

    assert 'numpy' in report.packages
    assert 'scipy' in report.packages
    assert 'no_version' not in report.packages
    assert 'dummy_module' not in report.packages
    assert 'pytest' not in report.packages
    assert 'mu_0' not in report.packages


def test_version_compare() -> None:
    assert scooby.meets_version('2', '1')
    assert not scooby.meets_version('1', '2')

    assert scooby.meets_version('1', '1')
    assert scooby.meets_version('0.1', '0.1')
    assert scooby.meets_version('0.1.0', '0.1.0')

    assert scooby.meets_version('1.0', '0.9')
    assert not scooby.meets_version('0.9', '1.0')

    assert scooby.meets_version('0.2.5', '0.1.8')
    assert not scooby.meets_version('0.1.8', '0.2.5')

    assert not scooby.meets_version('0.25.1', '0.25.2')
    assert scooby.meets_version('0.26.0', '0.25.2')
    assert scooby.meets_version('0.25.2', '0.25.2')

    assert not scooby.meets_version('0.25.2', '0.26')

    assert scooby.meets_version('0.28.0dev0', '0.25.2')

    with pytest.raises(
        ValueError,
        match='Version strings containing more than three parts cannot be parsed',
    ):
        scooby.meets_version('0.25.2.0', '0.26')


def test_import_os_error() -> None:
    # pyvips requires libvips, etc., to be installed
    # We don't have this on CI, so this should throw an error on import
    # Make sure scooby can handle it.
    with pytest.raises(OSError, match='cannot load'):
        import pyvips  # noqa: F401
    assert scooby.Report(['pyvips'])


@pytest.mark.skipif(not sys.platform.startswith('linux'), reason='Not Linux.')
def test_import_time() -> None:
    # Relevant for packages which provide a CLI:
    # How long does it take to import?
    cmd = ['time', '-f', '%U', sys.executable, '-c', 'import scooby']
    # Run it twice, just in case.
    subprocess.run(cmd, check=False)
    subprocess.run(cmd, check=False)
    # Capture it
    out = subprocess.run(cmd, check=False, capture_output=True)

    # Currently we check t < 0.2 s.
    t_expected = 0.2
    assert float(out.stderr.decode('utf-8')[:-1]) < t_expected


@pytest.mark.script_launch_mode('subprocess')
def test_cli(script_runner: ScriptRunner) -> None:
    # help
    for inp in ['--help', '-h']:
        ret = script_runner.run(['scooby', inp])
        assert ret.success
        assert 'Great Dane turned Python environment detective' in ret.stdout

    def rep_comp(inp: str) -> str:
        # Exclude time to avoid errors.
        # Exclude scooby-version, because if run locally without having scooby
        # installed it will be "unknown" for the __main__ one.
        out = inp.split('OS :')[1]
        if 'scooby' in inp:
            out = out.split('scooby :')[0]
        else:  # As the endings are different.
            out = out.split('--------')[0]
        return out

    # default: scooby-Report
    ret = script_runner.run(['scooby'])
    assert ret.success
    assert rep_comp(scooby.Report().__repr__()) == rep_comp(ret.stdout)

    # default: scooby-Report with sort and no-opt
    ret = script_runner.run(['scooby', 'numpy', '--no-opt', '--sort'])
    assert ret.success
    test = scooby.Report('numpy', optional=[], sort=True).__repr__()
    print(rep_comp(test))
    print(rep_comp(ret.stdout))
    assert rep_comp(test) == rep_comp(ret.stdout)

    # version -- VIA scooby/__main__.py by calling the folder scooby.
    ret = script_runner.run([sys.executable, 'scooby', '--version'])
    assert ret.success
    assert 'scooby v' in ret.stdout

    # version -- VIA scooby/__main__.py by calling the file.
    ret = script_runner.run([sys.executable, Path('scooby') / '__main__.py', '--version'])
    assert ret.success
    assert 'scooby v' in ret.stdout

    # default: scooby-Report for pytest
    ret = script_runner.run(['scooby', '--report', 'pytest'])
    assert ret.success
    assert 'pytest' in ret.stdout
    assert 'iniconfig' in ret.stdout

    # CLI report should match AutoReport
    from_cli = ret.stdout
    from_autoreport = repr(scooby.AutoReport('pytest'))
    assert rep_comp(from_cli) == rep_comp(from_autoreport)

    # handle error -- no distribution
    ret = script_runner.run(['scooby', '--report', 'pathlib'])
    assert not ret.success
    assert 'importlib' in ret.stderr

    # handle error -- not found
    ret = script_runner.run(['scooby', '--report', 'foobar'])
    assert not ret.success
    assert 'no Report' in ret.stderr


def test_auto_report() -> None:
    report = scooby.AutoReport('pytest')
    assert 'pytest' in report.packages
    assert 'iniconfig' in report.packages


@pytest.mark.parametrize(
    ('requirement', 'expected'),
    [
        ('x==0.4', 'x'),
        ('x<0.2', 'x'),
        ('x!=0.42', 'x'),
        ('y>1.0', 'y'),
        ("z; python_version<'3.10'", 'z'),
        ('w >= 1.2', 'w'),
        ('x @ git+https://github.com/foo/bar.git@main', 'x'),
    ],
)
def test_get_distribution_dependencies(
    monkeypatch: pytest.MonkeyPatch,
    requirement: str,
    expected: str,
) -> None:
    class FakeDist:
        requires = [requirement]

    def fake_distribution(_dist_name: str) -> None:
        return FakeDist()

    monkeypatch.setattr('scooby.report.distribution', fake_distribution)

    deps = scooby.report.get_distribution_dependencies('fakepkg')
    assert deps == [expected]


def test_get_distribution_dependencies_no_deps() -> None:
    deps = scooby.report.get_distribution_dependencies('numpy')
    assert deps == []
    deps = scooby.report.get_distribution_dependencies('numpy', separate_extras=True)
    assert deps == {'core': [], 'optional': {}}


def test_get_distribution_dependencies_uniqueness_and_order(
    monkeypatch: pytest.MonkeyPatch,
) -> None:
    class FakeDist:
        requires = ['y==0.42', 'x<1.5', 'x>1.0']

    def fake_distribution(_dist_name: str) -> None:
        return FakeDist()

    monkeypatch.setattr('scooby.report.distribution', fake_distribution)

    deps = scooby.report.get_distribution_dependencies('fakepkg')

    # 'y' comes first, then 'x' (deduplicated but ordered by first occurrence)
    assert deps == ['y', 'x']


def test_get_distribution_dependencies_separate_extras() -> None:
    all_deps = scooby.report.get_distribution_dependencies('beautifulsoup4', separate_extras=False)
    assert all_deps == [
        'soupsieve',
        'typing-extensions',
        'cchardet',
        'chardet',
        'charset-normalizer',
        'html5lib',
        'lxml',
    ]

    separate_deps = scooby.report.get_distribution_dependencies(
        'beautifulsoup4',
        separate_extras=True,
    )
    assert separate_deps == {
        'core': ['soupsieve', 'typing-extensions'],
        'optional': {
            'cchardet': ['cchardet'],
            'chardet': ['chardet'],
            'charset-normalizer': ['charset-normalizer'],
            'html5lib': ['html5lib'],
            'lxml': ['lxml'],
        },
    }

    # Flatten back into one list
    flat_list = separate_deps['core'] + [
        pkg for dep_list in separate_deps['optional'].values() for pkg in dep_list
    ]
    assert flat_list == all_deps

    # Check that optional keys match actual extras from distribution
    dist = distribution('beautifulsoup4')
    extras_names = list(dist.metadata.get_all('Provides-Extra') or [])
    assert list(separate_deps['optional'].keys()) == extras_names