import inspect
import unittest
from unittest import mock
import warnings
from scrapy.exceptions import ScrapyDeprecationWarning
from scrapy.utils.deprecate import create_deprecated_class, update_classpath


class MyWarning(UserWarning):
    pass


class SomeBaseClass:
    pass


class NewName(SomeBaseClass):
    pass


class WarnWhenSubclassedTest(unittest.TestCase):

    def _mywarnings(self, w, category=MyWarning):
        return [x for x in w if x.category is MyWarning]

    def test_no_warning_on_definition(self):
        with warnings.catch_warnings(record=True) as w:
            create_deprecated_class('Deprecated', NewName)

        w = self._mywarnings(w)
        self.assertEqual(w, [])

    def test_subclassing_warning_message(self):
        Deprecated = create_deprecated_class('Deprecated', NewName,
                                             warn_category=MyWarning)

        with warnings.catch_warnings(record=True) as w:
            class UserClass(Deprecated):
                pass

        w = self._mywarnings(w)
        self.assertEqual(len(w), 1)
        self.assertEqual(
            str(w[0].message),
            "tests.test_utils_deprecate.UserClass inherits from "
            "deprecated class tests.test_utils_deprecate.Deprecated, "
            "please inherit from tests.test_utils_deprecate.NewName."
            " (warning only on first subclass, there may be others)"
        )
        self.assertEqual(w[0].lineno, inspect.getsourcelines(UserClass)[1])

    def test_custom_class_paths(self):
        Deprecated = create_deprecated_class('Deprecated', NewName,
                                             new_class_path='foo.NewClass',
                                             old_class_path='bar.OldClass',
                                             warn_category=MyWarning)

        with warnings.catch_warnings(record=True) as w:
            class UserClass(Deprecated):
                pass

            _ = Deprecated()

        w = self._mywarnings(w)
        self.assertEqual(len(w), 2)
        self.assertIn('foo.NewClass', str(w[0].message))
        self.assertIn('bar.OldClass', str(w[0].message))
        self.assertIn('foo.NewClass', str(w[1].message))
        self.assertIn('bar.OldClass', str(w[1].message))

    def test_subclassing_warns_only_on_direct_childs(self):
        Deprecated = create_deprecated_class('Deprecated', NewName,
                                             warn_once=False,
                                             warn_category=MyWarning)

        with warnings.catch_warnings(record=True) as w:
            class UserClass(Deprecated):
                pass

            class NoWarnOnMe(UserClass):
                pass

        w = self._mywarnings(w)
        self.assertEqual(len(w), 1)
        self.assertIn('UserClass', str(w[0].message))

    def test_subclassing_warns_once_by_default(self):
        Deprecated = create_deprecated_class('Deprecated', NewName,
                                             warn_category=MyWarning)

        with warnings.catch_warnings(record=True) as w:
            class UserClass(Deprecated):
                pass

            class FooClass(Deprecated):
                pass

            class BarClass(Deprecated):
                pass

        w = self._mywarnings(w)
        self.assertEqual(len(w), 1)
        self.assertIn('UserClass', str(w[0].message))

    def test_warning_on_instance(self):
        Deprecated = create_deprecated_class('Deprecated', NewName,
                                             warn_category=MyWarning)

        # ignore subclassing warnings
        with warnings.catch_warnings():
            warnings.simplefilter('ignore', ScrapyDeprecationWarning)

            class UserClass(Deprecated):
                pass

        with warnings.catch_warnings(record=True) as w:
            _, lineno = Deprecated(), inspect.getlineno(inspect.currentframe())
            _ = UserClass()  # subclass instances don't warn

        w = self._mywarnings(w)
        self.assertEqual(len(w), 1)
        self.assertEqual(
            str(w[0].message),
            "tests.test_utils_deprecate.Deprecated is deprecated, "
            "instantiate tests.test_utils_deprecate.NewName instead."
        )
        self.assertEqual(w[0].lineno, lineno)

    def test_warning_auto_message(self):
        with warnings.catch_warnings(record=True) as w:
            Deprecated = create_deprecated_class('Deprecated', NewName)

            class UserClass2(Deprecated):
                pass

        msg = str(w[0].message)
        self.assertIn("tests.test_utils_deprecate.NewName", msg)
        self.assertIn("tests.test_utils_deprecate.Deprecated", msg)

    def test_issubclass(self):
        with warnings.catch_warnings():
            warnings.simplefilter('ignore', ScrapyDeprecationWarning)
            DeprecatedName = create_deprecated_class('DeprecatedName', NewName)

            class UpdatedUserClass1(NewName):
                pass

            class UpdatedUserClass1a(NewName):
                pass

            class OutdatedUserClass1(DeprecatedName):
                pass

            class OutdatedUserClass1a(DeprecatedName):
                pass

            class UnrelatedClass:
                pass

            class OldStyleClass:
                pass

        assert issubclass(UpdatedUserClass1, NewName)
        assert issubclass(UpdatedUserClass1a, NewName)
        assert issubclass(UpdatedUserClass1, DeprecatedName)
        assert issubclass(UpdatedUserClass1a, DeprecatedName)
        assert issubclass(OutdatedUserClass1, DeprecatedName)
        assert not issubclass(UnrelatedClass, DeprecatedName)
        assert not issubclass(OldStyleClass, DeprecatedName)
        assert not issubclass(OldStyleClass, DeprecatedName)
        assert not issubclass(OutdatedUserClass1, OutdatedUserClass1a)
        assert not issubclass(OutdatedUserClass1a, OutdatedUserClass1)

        self.assertRaises(TypeError, issubclass, object(), DeprecatedName)

    def test_isinstance(self):
        with warnings.catch_warnings():
            warnings.simplefilter('ignore', ScrapyDeprecationWarning)
            DeprecatedName = create_deprecated_class('DeprecatedName', NewName)

            class UpdatedUserClass2(NewName):
                pass

            class UpdatedUserClass2a(NewName):
                pass

            class OutdatedUserClass2(DeprecatedName):
                pass

            class OutdatedUserClass2a(DeprecatedName):
                pass

            class UnrelatedClass:
                pass

            class OldStyleClass:
                pass

        assert isinstance(UpdatedUserClass2(), NewName)
        assert isinstance(UpdatedUserClass2a(), NewName)
        assert isinstance(UpdatedUserClass2(), DeprecatedName)
        assert isinstance(UpdatedUserClass2a(), DeprecatedName)
        assert isinstance(OutdatedUserClass2(), DeprecatedName)
        assert isinstance(OutdatedUserClass2a(), DeprecatedName)
        assert not isinstance(OutdatedUserClass2a(), OutdatedUserClass2)
        assert not isinstance(OutdatedUserClass2(), OutdatedUserClass2a)
        assert not isinstance(UnrelatedClass(), DeprecatedName)
        assert not isinstance(OldStyleClass(), DeprecatedName)

    def test_clsdict(self):
        with warnings.catch_warnings():
            warnings.simplefilter('ignore', ScrapyDeprecationWarning)
            Deprecated = create_deprecated_class('Deprecated', NewName, {'foo': 'bar'})

        self.assertEqual(Deprecated.foo, 'bar')

    def test_deprecate_a_class_with_custom_metaclass(self):
        Meta1 = type('Meta1', (type,), {})
        New = Meta1('New', (), {})
        create_deprecated_class('Deprecated', New)

    def test_deprecate_subclass_of_deprecated_class(self):
        with warnings.catch_warnings(record=True) as w:
            warnings.simplefilter('always')
            Deprecated = create_deprecated_class('Deprecated', NewName,
                                                 warn_category=MyWarning)
            AlsoDeprecated = create_deprecated_class('AlsoDeprecated', Deprecated,
                                                     new_class_path='foo.Bar',
                                                     warn_category=MyWarning)

        w = self._mywarnings(w)
        self.assertEqual(len(w), 0, str(map(str, w)))

        with warnings.catch_warnings(record=True) as w:
            AlsoDeprecated()

            class UserClass(AlsoDeprecated):
                pass

        w = self._mywarnings(w)
        self.assertEqual(len(w), 2)
        self.assertIn('AlsoDeprecated', str(w[0].message))
        self.assertIn('foo.Bar', str(w[0].message))
        self.assertIn('AlsoDeprecated', str(w[1].message))
        self.assertIn('foo.Bar', str(w[1].message))

    def test_inspect_stack(self):
        with mock.patch('inspect.stack', side_effect=IndexError):
            with warnings.catch_warnings(record=True) as w:
                DeprecatedName = create_deprecated_class('DeprecatedName', NewName)

                class SubClass(DeprecatedName):
                    pass

        self.assertIn("Error detecting parent module", str(w[0].message))


@mock.patch('scrapy.utils.deprecate.DEPRECATION_RULES',
            [('scrapy.contrib.pipeline.', 'scrapy.pipelines.'),
             ('scrapy.contrib.', 'scrapy.extensions.')])
class UpdateClassPathTest(unittest.TestCase):

    def test_old_path_gets_fixed(self):
        with warnings.catch_warnings(record=True) as w:
            output = update_classpath('scrapy.contrib.debug.Debug')
        self.assertEqual(output, 'scrapy.extensions.debug.Debug')
        self.assertEqual(len(w), 1)
        self.assertIn("scrapy.contrib.debug.Debug", str(w[0].message))
        self.assertIn("scrapy.extensions.debug.Debug", str(w[0].message))

    def test_sorted_replacement(self):
        with warnings.catch_warnings():
            warnings.simplefilter('ignore', ScrapyDeprecationWarning)
            output = update_classpath('scrapy.contrib.pipeline.Pipeline')
        self.assertEqual(output, 'scrapy.pipelines.Pipeline')

    def test_unmatched_path_stays_the_same(self):
        with warnings.catch_warnings(record=True) as w:
            output = update_classpath('scrapy.unmatched.Path')
        self.assertEqual(output, 'scrapy.unmatched.Path')
        self.assertEqual(len(w), 0)
