# pylint: disable=missing-docstring
# pylint: disable=invalid-name
# pylint: disable=unused-argument
# pylint: disable=no-self-use
# pylint: disable=unnecessary-lambda

import abc
import functools
import textwrap
import unittest
from typing import Optional, List, Type  # pylint: disable=unused-import

import icontract
from icontract._globals import CallableT
import tests.error
import tests.mock


class TestOK(unittest.TestCase):
    def test_with_condition_as_lambda(self) -> None:
        @icontract.ensure(lambda result, x: result > x)
        def some_func(x: int, y: int = 5) -> int:
            return x + y

        some_func(x=5)
        some_func(x=5, y=10)


class TestViolation(unittest.TestCase):
    def test_with_condition(self) -> None:
        @icontract.ensure(lambda result, x: result > x)
        def some_func(x: int, y: int = 5) -> int:
            return x - y

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            some_func(x=1)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                result > x:
                result was -4
                x was 1
                y was 5"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_condition_as_function(self) -> None:
        def some_condition(result: int) -> bool:
            return result > 3

        @icontract.ensure(some_condition)
        def some_func(x: int) -> int:
            return x

        # Valid call
        some_func(x=4)

        # Invalid call
        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            some_func(x=1)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                some_condition:
                result was 1
                x was 1"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_condition_as_function_with_default_argument_value(self) -> None:
        def some_condition(result: int, y: int = 0) -> bool:
            return result > y

        @icontract.ensure(some_condition)
        def some_func(x: int) -> int:
            return x

        # Valid call
        some_func(x=1)

        # Invalid call
        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            some_func(x=-1)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                some_condition:
                result was -1
                x was -1"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_condition_as_function_with_default_argument_value_set(self) -> None:
        def some_condition(result: int, y: int = 0) -> bool:
            return result > y

        @icontract.ensure(some_condition)
        def some_func(x: int, y: int) -> int:
            return x

        # Valid call
        some_func(x=-1, y=-2)

        # Invalid call
        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            some_func(x=1, y=3)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                some_condition:
                result was 1
                x was 1
                y was 3"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_with_description(self) -> None:
        @icontract.ensure(lambda result, x: result > x, "expected summation")
        def some_func(x: int, y: int = 5) -> int:
            return x - y

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            some_func(x=1)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                expected summation: result > x:
                result was -4
                x was 1
                y was 5"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_with_stacked_decorators(self) -> None:
        def mydecorator(f: CallableT) -> CallableT:
            @functools.wraps(f)
            def wrapped(*args, **kwargs):  # type: ignore
                result = f(*args, **kwargs)
                return result

            return wrapped  # type: ignore

        some_var = 1
        another_var = 2

        @mydecorator
        @icontract.ensure(lambda result, x: x < result + some_var)
        @icontract.ensure(lambda result, y: y > result + another_var)
        @mydecorator
        def some_func(x: int, y: int) -> int:
            return 100

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            some_func(x=0, y=10)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                y > result + another_var:
                another_var was 2
                result was 100
                x was 0
                y was 10"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_with_default_values_outer(self) -> None:
        @icontract.ensure(lambda result, c: result % c == 0)
        @icontract.ensure(lambda result, b: result < b)
        def some_func(a: int, b: int = 21, c: int = 2) -> int:
            return a

        # Check first the outer post condition
        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            some_func(a=13)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                result % c == 0:
                a was 13
                b was 21
                c was 2
                result was 13"""), tests.error.wo_mandatory_location(str(violation_error)))

        # Check the inner post condition
        violation_error = None
        try:
            some_func(a=36)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                result < b:
                a was 36
                b was 21
                c was 2
                result was 36"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_only_result(self) -> None:
        @icontract.ensure(lambda result: result > 3)
        def some_func(x: int) -> int:
            return 0

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            some_func(x=10 * 1000)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                result > 3:
                result was 0
                x was 10000"""), tests.error.wo_mandatory_location(str(violation_error)))


class TestError(unittest.TestCase):
    def test_as_type(self) -> None:
        @icontract.ensure(lambda result: result > 0, error=ValueError)
        def some_func(x: int) -> int:
            return x

        value_error = None  # type: Optional[ValueError]
        try:
            some_func(x=0)
        except ValueError as err:
            value_error = err

        self.assertIsNotNone(value_error)
        self.assertIsInstance(value_error, ValueError)
        self.assertEqual(
            textwrap.dedent("""\
                result > 0:
                result was 0
                x was 0"""), tests.error.wo_mandatory_location(str(value_error)))

    def test_as_function(self) -> None:
        @icontract.ensure(lambda result: result > 0, error=lambda result: ValueError("result must be positive."))
        def some_func(x: int) -> int:
            return x

        value_error = None  # type: Optional[ValueError]
        try:
            some_func(x=0)
        except ValueError as err:
            value_error = err

        self.assertIsNotNone(value_error)
        self.assertIsInstance(value_error, ValueError)
        self.assertEqual('result must be positive.', str(value_error))

    def test_with_empty_args(self) -> None:
        @icontract.ensure(lambda result: result > 0, error=lambda: ValueError("result must be positive"))
        def some_func(x: int) -> int:
            return x

        value_error = None  # type: Optional[ValueError]
        try:
            some_func(x=0)
        except ValueError as err:
            value_error = err

        self.assertIsNotNone(value_error)
        self.assertIsInstance(value_error, ValueError)
        self.assertEqual('result must be positive', str(value_error))

    def test_with_different_args_from_condition(self) -> None:
        @icontract.ensure(
            lambda result: result > 0, error=lambda x, result: ValueError("x is {}, result is {}".format(x, result)))
        def some_func(x: int) -> int:
            return x

        value_error = None  # type: Optional[ValueError]
        try:
            some_func(x=0)
        except ValueError as err:
            value_error = err

        self.assertIsNotNone(value_error)
        self.assertIsInstance(value_error, ValueError)
        self.assertEqual('x is 0, result is 0', str(value_error))


class TestToggling(unittest.TestCase):
    def test_disabled(self) -> None:
        @icontract.ensure(lambda x, result: x > result, enabled=False)
        def some_func(x: int) -> int:
            return 123

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            result = some_func(x=1234)
            self.assertEqual(123, result)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNone(violation_error)


class TestInClass(unittest.TestCase):
    def test_postcondition_in_static_method(self) -> None:
        class SomeClass:
            @staticmethod
            @icontract.ensure(lambda result: result != 0)
            def some_func(x: int) -> int:
                return x

        result = SomeClass.some_func(x=1)
        self.assertEqual(1, result)

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            _ = SomeClass.some_func(x=0)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                result != 0:
                result was 0
                x was 0"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_postcondition_in_class_method(self) -> None:
        class SomeClass:
            @classmethod
            @icontract.ensure(lambda result: result != 0)
            def some_func(cls: Type['SomeClass'], x: int) -> int:
                return x

        result = SomeClass.some_func(x=1)
        self.assertEqual(1, result)

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            _ = SomeClass.some_func(x=0)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                result != 0:
                result was 0
                x was 0"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_postcondition_in_abstract_static_method(self) -> None:
        class SomeAbstract(icontract.DBC):
            @staticmethod
            @abc.abstractmethod
            @icontract.ensure(lambda result: result != 0)
            def some_func(x: int) -> int:
                raise NotImplementedError()

        class SomeClass(SomeAbstract):
            @staticmethod
            def some_func(x: int) -> int:
                return x

        result = SomeClass.some_func(x=1)
        self.assertEqual(1, result)

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            _ = SomeClass.some_func(x=0)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                result != 0:
                result was 0
                x was 0"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_postcondition_in_abstract_class_method(self) -> None:
        class Abstract(icontract.DBC):
            @classmethod
            @abc.abstractmethod
            @icontract.ensure(lambda result: result != 0)
            def some_func(cls: Type['Abstract'], x: int) -> int:
                pass

        class SomeClass(Abstract):
            @classmethod
            def some_func(cls: Type['SomeClass'], x: int) -> int:
                return x

        result = SomeClass.some_func(x=1)
        self.assertEqual(1, result)

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            _ = SomeClass.some_func(x=0)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                result != 0:
                result was 0
                x was 0"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_getter(self) -> None:
        class SomeClass:
            def __init__(self) -> None:
                self._some_prop = -1

            @property
            @icontract.ensure(lambda result: result > 0)
            def some_prop(self) -> int:
                return self._some_prop

            def __repr__(self) -> str:
                return "an instance of {}".format(self.__class__.__name__)

        some_inst = SomeClass()

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            _ = some_inst.some_prop
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                result > 0:
                result was -1
                self was an instance of SomeClass"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_setter(self) -> None:
        class SomeClass:
            @property
            def some_prop(self) -> int:
                return 0

            @some_prop.setter
            @icontract.ensure(lambda self: self.some_prop > 0)
            def some_prop(self, value: int) -> None:
                pass

            def __repr__(self) -> str:
                return "an instance of {}".format(self.__class__.__name__)

        some_inst = SomeClass()

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            some_inst.some_prop = -1
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                self.some_prop > 0:
                result was None
                self was an instance of SomeClass
                self.some_prop was 0
                value was -1"""), tests.error.wo_mandatory_location(str(violation_error)))

    def test_deleter(self) -> None:
        class SomeClass:
            def __init__(self) -> None:
                self._some_prop = -1

            @property
            def some_prop(self) -> int:
                return self._some_prop

            @some_prop.deleter
            @icontract.ensure(lambda self: self.some_prop > 0)
            def some_prop(self) -> None:
                pass

            def __repr__(self) -> str:
                return "an instance of {}".format(self.__class__.__name__)

        some_inst = SomeClass()

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            del some_inst.some_prop
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual(
            textwrap.dedent("""\
                self.some_prop > 0:
                result was None
                self was an instance of SomeClass
                self.some_prop was -1"""), tests.error.wo_mandatory_location(str(violation_error)))


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