# Test methods with long descriptive names can omit docstrings
# pylint: disable=missing-docstring
import pickle
import unittest

from packaging.version import Version

import Orange

from Orange.base import SklLearner, Learner, Model
from Orange.data import Domain, Table
from Orange.preprocess import Discretize, Randomize, Continuize
from Orange.regression import LinearRegressionLearner
from Orange.util import OrangeDeprecationWarning


class DummyLearner(Learner):

    def fit(self, *_, **__):
        return unittest.mock.Mock()


class DummySklLearner(SklLearner):

    def fit(self, *_, **__):
        return unittest.mock.Mock()


class DummyLearnerPP(Learner):

    preprocessors = (Randomize(),)


class TestLearner(unittest.TestCase):
    def test_uses_default_preprocessors_unless_custom_pps_specified(self):
        """Learners should use their default preprocessors unless custom
        preprocessors were passed in to the constructor"""
        learner = DummyLearner()
        self.assertEqual(
            type(learner).preprocessors, tuple(learner.active_preprocessors),
            'Learner should use default preprocessors, unless preprocessors '
            'were specified in init')

    def test_overrides_custom_preprocessors(self):
        """Passing preprocessors to the learner constructor should override the
        default preprocessors defined on the learner"""
        pp = Discretize()
        learner = DummyLearnerPP(preprocessors=(pp,))
        self.assertEqual(
            tuple(learner.active_preprocessors), (pp,),
            'Learner should override default preprocessors when specified in '
            'constructor')

    def test_use_default_preprocessors_property(self):
        """We can specify that we want to use default preprocessors despite
        passing our own ones in the constructor"""
        learner = DummyLearnerPP(preprocessors=(Discretize(),))
        learner.use_default_preprocessors = True

        preprocessors = list(learner.active_preprocessors)
        self.assertEqual(
            len(preprocessors), 2,
            'Learner did not properly insert custom preprocessor into '
            'preprocessor list')
        self.assertIsInstance(
            preprocessors[0], Discretize,
            'Custom preprocessor was inserted in incorrect order')
        self.assertIsInstance(preprocessors[1], Randomize)

    def test_preprocessors_can_be_passed_in_as_non_iterable(self):
        """For convenience, we can pass a single preprocessor instance"""
        pp = Discretize()
        learner = DummyLearnerPP(preprocessors=pp)
        self.assertEqual(
            tuple(learner.active_preprocessors), (pp,),
            'Preprocessors should be able to be passed in as single object '
            'as well as an iterable object')

    def test_preprocessors_can_be_passed_in_as_generator(self):
        """Since we support iterables, we should support generators as well"""
        pp = (Discretize(),)
        learner = DummyLearnerPP(p for p in pp)
        self.assertEqual(
            tuple(learner.active_preprocessors), pp,
            'Preprocessors should be able to be passed in as single object '
            'as well as an iterable object')

    def test_callback(self):
        callback = unittest.mock.Mock()
        learner = DummyLearner(preprocessors=[Discretize(), Randomize()])
        learner(Table("iris"), callback)
        args = [x[0][0] for x in callback.call_args_list]
        self.assertEqual(min(args), 0)
        self.assertEqual(max(args), 1)
        self.assertListEqual(args, sorted(args))


class TestSklLearner(unittest.TestCase):
    def test_sklearn_supports_weights(self):
        """Check that the SklLearner correctly infers whether or not the
        learner supports weights"""

        class DummySklLearner:
            def fit(self, X, y, sample_weight=None):
                pass

        class DummyLearner(SklLearner):
            __wraps__ = DummySklLearner

        with self.assertWarns(OrangeDeprecationWarning):
            self.assertTrue(DummyLearner().supports_weights)

        class DummySklLearner:
            def fit(self, X, y):
                pass

        class DummyLearner(SklLearner):
            __wraps__ = DummySklLearner

        with self.assertWarns(OrangeDeprecationWarning):
            self.assertFalse(DummyLearner().supports_weights)

    def test_linreg(self):
        self.assertTrue(
            LinearRegressionLearner().supports_weights,
            "Either LinearRegression no longer supports weighted tables or "
            "SklLearner.supports_weights is out-of-date.")

    def test_callback(self):
        callback = unittest.mock.Mock()
        learner = DummySklLearner(preprocessors=[Continuize(), Randomize()])
        learner(Table("iris"), callback)
        args = [x[0][0] for x in callback.call_args_list]
        self.assertEqual(min(args), 0)
        self.assertEqual(max(args), 1)
        self.assertListEqual(args, sorted(args))

    def test_supports_weights_property(self):
        """This test is to be included in the 3.37 release and will fail in
        version 3.39. This serves as a reminder."""
        if Version(Orange.__version__) >= Version("3.39"):
            self.fail(
                "`SklLearner.supports_weights` as a property that parses fit() "
                "was deprecated in 3.37. Replace it with `supports_weights = False`"
            )


class TestModel(unittest.TestCase):
    def test_pickle(self):
        """Make sure data is not saved when pickling a model."""
        model = Model(Domain([]))
        model.original_data = [1, 2, 3]
        model2 = pickle.loads(pickle.dumps(model))
        self.assertEqual(model.domain, model2.domain)
        self.assertEqual(model.original_data, [1, 2, 3])
        self.assertEqual(model2.original_data, None)


if __name__ == "__main__":
    unittest.main()
