import itertools
import operator
import sys
import unittest
import warnings

from test.support import cpython_only, import_helper

_testcapi = import_helper.import_module('_testcapi')
from _testcapi import PY_SSIZE_T_MAX, PY_SSIZE_T_MIN

try:
    from _testbuffer import ndarray
except ImportError:
    ndarray = None

NULL = None

class BadDescr:
    def __get__(self, obj, objtype=None):
        raise RuntimeError

class WithDunder:
    def _meth(self, *args):
        if self.val:
            return self.val
        if self.exc:
            raise self.exc
    @classmethod
    def with_val(cls, val):
        obj = super().__new__(cls)
        obj.val = val
        obj.exc = None
        setattr(cls, cls.methname, cls._meth)
        return obj

    @classmethod
    def with_exc(cls, exc):
        obj = super().__new__(cls)
        obj.val = None
        obj.exc = exc
        setattr(cls, cls.methname, cls._meth)
        return obj

class HasBadAttr:
    def __new__(cls):
        obj = super().__new__(cls)
        setattr(cls, cls.methname, BadDescr())
        return obj


class IndexLike(WithDunder):
    methname = '__index__'

class IntLike(WithDunder):
    methname = '__int__'

class FloatLike(WithDunder):
    methname = '__float__'


def subclassof(base):
    return type(base.__name__ + 'Subclass', (base,), {})


class SomeError(Exception):
    pass

class OtherError(Exception):
    pass


class CAPITest(unittest.TestCase):
    def test_check(self):
        # Test PyNumber_Check()
        check = _testcapi.number_check

        self.assertTrue(check(1))
        self.assertTrue(check(IndexLike.with_val(1)))
        self.assertTrue(check(IntLike.with_val(99)))
        self.assertTrue(check(0.5))
        self.assertTrue(check(FloatLike.with_val(4.25)))
        self.assertTrue(check(1+2j))

        self.assertFalse(check([]))
        self.assertFalse(check("abc"))
        self.assertFalse(check(object()))
        self.assertFalse(check(NULL))

    def test_unary_ops(self):
        methmap = {'__neg__': _testcapi.number_negative,   # PyNumber_Negative()
                   '__pos__': _testcapi.number_positive,   # PyNumber_Positive()
                   '__abs__': _testcapi.number_absolute,   # PyNumber_Absolute()
                   '__invert__': _testcapi.number_invert}  # PyNumber_Invert()

        for name, func in methmap.items():
            # Generic object, has no tp_as_number structure
            self.assertRaises(TypeError, func, object())

            # C-API function accepts NULL
            self.assertRaises(SystemError, func, NULL)

            # Behave as corresponding unary operation
            op = getattr(operator, name)
            for x in [0, 42, -1, 3.14, 1+2j]:
                try:
                    op(x)
                except TypeError:
                    self.assertRaises(TypeError, func, x)
                else:
                    self.assertEqual(func(x), op(x))

    def test_binary_ops(self):
        methmap = {'__add__': _testcapi.number_add,   # PyNumber_Add()
                   '__sub__': _testcapi.number_subtract,  # PyNumber_Subtract()
                   '__mul__': _testcapi.number_multiply,  # PyNumber_Multiply()
                   '__matmul__': _testcapi.number_matrixmultiply,  # PyNumber_MatrixMultiply()
                   '__floordiv__': _testcapi.number_floordivide,  # PyNumber_FloorDivide()
                   '__truediv__': _testcapi.number_truedivide,  # PyNumber_TrueDivide()
                   '__mod__': _testcapi.number_remainder,  # PyNumber_Remainder()
                   '__divmod__': _testcapi.number_divmod,  # PyNumber_Divmod()
                   '__lshift__': _testcapi.number_lshift,  # PyNumber_Lshift()
                   '__rshift__': _testcapi.number_rshift,  # PyNumber_Rshift()
                   '__and__': _testcapi.number_and,  # PyNumber_And()
                   '__xor__': _testcapi.number_xor,  # PyNumber_Xor()
                   '__or__': _testcapi.number_or,  # PyNumber_Or()
                   '__pow__': _testcapi.number_power,  # PyNumber_Power()
                   '__iadd__': _testcapi.number_inplaceadd,   # PyNumber_InPlaceAdd()
                   '__isub__': _testcapi.number_inplacesubtract,  # PyNumber_InPlaceSubtract()
                   '__imul__': _testcapi.number_inplacemultiply,  # PyNumber_InPlaceMultiply()
                   '__imatmul__': _testcapi.number_inplacematrixmultiply,  # PyNumber_InPlaceMatrixMultiply()
                   '__ifloordiv__': _testcapi.number_inplacefloordivide,  # PyNumber_InPlaceFloorDivide()
                   '__itruediv__': _testcapi.number_inplacetruedivide,  # PyNumber_InPlaceTrueDivide()
                   '__imod__': _testcapi.number_inplaceremainder,  # PyNumber_InPlaceRemainder()
                   '__ilshift__': _testcapi.number_inplacelshift,  # PyNumber_InPlaceLshift()
                   '__irshift__': _testcapi.number_inplacershift,  # PyNumber_InPlaceRshift()
                   '__iand__': _testcapi.number_inplaceand,  # PyNumber_InPlaceAnd()
                   '__ixor__': _testcapi.number_inplacexor,  # PyNumber_InPlaceXor()
                   '__ior__': _testcapi.number_inplaceor,  # PyNumber_InPlaceOr()
                   '__ipow__': _testcapi.number_inplacepower,  # PyNumber_InPlacePower()
                   }

        for name, func in methmap.items():
            cases = [0, 42, 3.14, -1, 123, 1+2j]

            # Generic object, has no tp_as_number structure
            for x in cases:
                self.assertRaises(TypeError, func, object(), x)
                self.assertRaises(TypeError, func, x, object())

            # Behave as corresponding binary operation
            op = getattr(operator, name, divmod)
            for x, y in itertools.combinations(cases, 2):
                try:
                    op(x, y)
                except (TypeError, ValueError, ZeroDivisionError) as exc:
                    self.assertRaises(exc.__class__, func, x, y)
                else:
                    self.assertEqual(func(x, y), op(x, y))

            # CRASHES func(NULL, object())
            # CRASHES func(object(), NULL)

    @unittest.skipIf(ndarray is None, "needs _testbuffer")
    def test_misc_add(self):
        # PyNumber_Add(), PyNumber_InPlaceAdd()
        add = _testcapi.number_add
        inplaceadd = _testcapi.number_inplaceadd

        # test sq_concat/sq_inplace_concat slots
        a, b, r = [1, 2], [3, 4], [1, 2, 3, 4]
        self.assertEqual(add(a, b), r)
        self.assertEqual(a, [1, 2])
        self.assertRaises(TypeError, add, ndarray([1], (1,)), 2)
        a, b, r = [1, 2], [3, 4], [1, 2, 3, 4]
        self.assertEqual(inplaceadd(a, b), r)
        self.assertEqual(a, r)
        self.assertRaises(TypeError, inplaceadd, ndarray([1], (1,)), 2)

    @unittest.skipIf(ndarray is None, "needs _testbuffer")
    def test_misc_multiply(self):
        # PyNumber_Multiply(), PyNumber_InPlaceMultiply()
        multiply = _testcapi.number_multiply
        inplacemultiply = _testcapi.number_inplacemultiply

        # test sq_repeat/sq_inplace_repeat slots
        a, b, r = [1], 2, [1, 1]
        self.assertEqual(multiply(a, b), r)
        self.assertEqual((a, b), ([1], 2))
        self.assertEqual(multiply(b, a), r)
        self.assertEqual((a, b), ([1], 2))
        self.assertEqual(multiply([1], -1), [])
        self.assertRaises(TypeError, multiply, ndarray([1], (1,)), 2)
        self.assertRaises(TypeError, multiply, [1], 0.5)
        self.assertRaises(OverflowError, multiply, [1], PY_SSIZE_T_MAX + 1)
        self.assertRaises(MemoryError, multiply, [1, 2], PY_SSIZE_T_MAX//2 + 1)
        a, b, r = [1], 2, [1, 1]
        self.assertEqual(inplacemultiply(a, b), r)
        self.assertEqual((a, b), (r, 2))
        a = [1]
        self.assertEqual(inplacemultiply(b, a), r)
        self.assertEqual((a, b), ([1], 2))
        self.assertRaises(TypeError, inplacemultiply, ndarray([1], (1,)), 2)
        self.assertRaises(OverflowError, inplacemultiply, [1], PY_SSIZE_T_MAX + 1)
        self.assertRaises(MemoryError, inplacemultiply, [1, 2], PY_SSIZE_T_MAX//2 + 1)

    def test_misc_power(self):
        # PyNumber_Power()
        power = _testcapi.number_power

        class HasPow(WithDunder):
            methname = '__pow__'

        # ternary op
        self.assertEqual(power(4, 11, 5), pow(4, 11, 5))
        self.assertRaises(TypeError, power, 4, 11, 1.25)
        self.assertRaises(TypeError, power, 4, 11, HasPow.with_val(NotImplemented))
        self.assertRaises(TypeError, power, 4, 11, object())

    @cpython_only
    def test_rshift_print(self):
        # This tests correct syntax hint for py2 redirection (>>).
        rshift = _testcapi.number_rshift

        with self.assertRaises(TypeError) as context:
            rshift(print, 42)
        self.assertIn('Did you mean "print(<message>, '
                      'file=<output_stream>)"?', str(context.exception))
        with self.assertRaises(TypeError) as context:
            rshift(max, sys.stderr)
        self.assertNotIn('Did you mean ', str(context.exception))
        with self.assertRaises(TypeError) as context:
            rshift(1, "spam")

    def test_long(self):
        # Test PyNumber_Long()
        long = _testcapi.number_long

        self.assertEqual(long(42), 42)
        self.assertEqual(long(1.25), 1)
        self.assertEqual(long("42"), 42)
        self.assertEqual(long(b"42"), 42)
        self.assertEqual(long(bytearray(b"42")), 42)
        self.assertEqual(long(memoryview(b"42")), 42)
        self.assertEqual(long(IndexLike.with_val(99)), 99)
        self.assertEqual(long(IntLike.with_val(99)), 99)

        self.assertRaises(TypeError, long, IntLike.with_val(1.0))
        with warnings.catch_warnings():
            warnings.simplefilter("error", DeprecationWarning)
            self.assertRaises(DeprecationWarning, long, IntLike.with_val(True))
        with self.assertWarns(DeprecationWarning):
            self.assertEqual(long(IntLike.with_val(True)), 1)
        self.assertRaises(RuntimeError, long, IntLike.with_exc(RuntimeError))

        self.assertRaises(TypeError, long, 1j)
        self.assertRaises(TypeError, long, object())
        self.assertRaises(SystemError, long, NULL)

    def test_float(self):
        # Test PyNumber_Float()
        float_ = _testcapi.number_float

        self.assertEqual(float_(1.25), 1.25)
        self.assertEqual(float_(123), 123.)
        self.assertEqual(float_("1.25"), 1.25)

        self.assertEqual(float_(FloatLike.with_val(4.25)), 4.25)
        self.assertEqual(float_(IndexLike.with_val(99)), 99.0)
        self.assertEqual(float_(IndexLike.with_val(-1)), -1.0)

        self.assertRaises(TypeError, float_, FloatLike.with_val(687))
        with warnings.catch_warnings():
            warnings.simplefilter("error", DeprecationWarning)
            self.assertRaises(DeprecationWarning, float_, FloatLike.with_val(subclassof(float)(4.25)))
        with self.assertWarns(DeprecationWarning):
            self.assertEqual(float_(FloatLike.with_val(subclassof(float)(4.25))), 4.25)
        self.assertRaises(RuntimeError, float_, FloatLike.with_exc(RuntimeError))

        self.assertRaises(TypeError, float_, IndexLike.with_val(1.25))
        self.assertRaises(OverflowError, float_, IndexLike.with_val(2**2000))

        self.assertRaises(TypeError, float_, 1j)
        self.assertRaises(TypeError, float_, object())
        self.assertRaises(SystemError, float_, NULL)

    def test_index(self):
        # Test PyNumber_Index()
        index = _testcapi.number_index

        self.assertEqual(index(11), 11)

        with warnings.catch_warnings():
            warnings.simplefilter("error", DeprecationWarning)
            self.assertRaises(DeprecationWarning, index, IndexLike.with_val(True))
        with self.assertWarns(DeprecationWarning):
            self.assertEqual(index(IndexLike.with_val(True)), 1)
        self.assertRaises(TypeError, index, IndexLike.with_val(1.0))
        self.assertRaises(RuntimeError, index, IndexLike.with_exc(RuntimeError))

        self.assertRaises(TypeError, index, 1.25)
        self.assertRaises(TypeError, index, "42")
        self.assertRaises(TypeError, index, object())
        self.assertRaises(SystemError, index, NULL)

    def test_tobase(self):
        # Test PyNumber_ToBase()
        tobase = _testcapi.number_tobase

        self.assertEqual(tobase(10, 2), bin(10))
        self.assertEqual(tobase(11, 8), oct(11))
        self.assertEqual(tobase(16, 10), str(16))
        self.assertEqual(tobase(13, 16), hex(13))

        self.assertRaises(SystemError, tobase, NULL, 2)
        self.assertRaises(SystemError, tobase, 2, 3)
        self.assertRaises(TypeError, tobase, 1.25, 2)
        self.assertRaises(TypeError, tobase, "42", 2)

    def test_asssizet(self):
        # Test PyNumber_AsSsize_t()
        asssizet = _testcapi.number_asssizet

        for n in [*range(-6, 7), PY_SSIZE_T_MIN, PY_SSIZE_T_MAX]:
            self.assertEqual(asssizet(n, OverflowError), n)
        self.assertEqual(asssizet(PY_SSIZE_T_MAX+10, NULL), PY_SSIZE_T_MAX)
        self.assertEqual(asssizet(PY_SSIZE_T_MIN-10, NULL), PY_SSIZE_T_MIN)

        self.assertRaises(OverflowError, asssizet, PY_SSIZE_T_MAX + 10, OverflowError)
        self.assertRaises(RuntimeError, asssizet, PY_SSIZE_T_MAX + 10, RuntimeError)
        self.assertRaises(SystemError, asssizet, NULL, TypeError)


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