import array
import ctypes
import sys
import unittest
from ctypes import (CDLL, CFUNCTYPE, Structure,
                    POINTER, pointer, _Pointer, _pointer_type_cache,
                    byref, sizeof,
                    c_void_p, c_char_p,
                    c_byte, c_ubyte, c_short, c_ushort, c_int, c_uint,
                    c_long, c_ulong, c_longlong, c_ulonglong,
                    c_float, c_double)
from test.support import import_helper
_ctypes_test = import_helper.import_module("_ctypes_test")
from ._support import (_CData, PyCPointerType, Py_TPFLAGS_DISALLOW_INSTANTIATION,
                       Py_TPFLAGS_IMMUTABLETYPE)


ctype_types = [c_byte, c_ubyte, c_short, c_ushort, c_int, c_uint,
                 c_long, c_ulong, c_longlong, c_ulonglong, c_double, c_float]
python_types = [int, int, int, int, int, int,
                int, int, int, int, float, float]


class PointersTestCase(unittest.TestCase):
    def test_inheritance_hierarchy(self):
        self.assertEqual(_Pointer.mro(), [_Pointer, _CData, object])

        self.assertEqual(PyCPointerType.__name__, "PyCPointerType")
        self.assertEqual(type(PyCPointerType), type)

    def test_type_flags(self):
        for cls in _Pointer, PyCPointerType:
            with self.subTest(cls=cls):
                self.assertTrue(_Pointer.__flags__ & Py_TPFLAGS_IMMUTABLETYPE)
                self.assertFalse(_Pointer.__flags__ & Py_TPFLAGS_DISALLOW_INSTANTIATION)

    def test_metaclass_details(self):
        # Cannot call the metaclass __init__ more than once
        with self.assertRaisesRegex(SystemError, "already initialized"):
            PyCPointerType.__init__(POINTER(c_byte), 'ptr', (), {})

    def test_pointer_crash(self):

        class A(POINTER(c_ulong)):
            pass

        POINTER(c_ulong)(c_ulong(22))
        # Pointer can't set contents: has no _type_
        self.assertRaises(TypeError, A, c_ulong(33))

    def test_pass_pointers(self):
        dll = CDLL(_ctypes_test.__file__)
        func = dll._testfunc_p_p
        if sizeof(c_longlong) == sizeof(c_void_p):
            func.restype = c_longlong
        else:
            func.restype = c_long

        i = c_int(12345678)
        address = func(byref(i))
        self.assertEqual(c_int.from_address(address).value, 12345678)

        func.restype = POINTER(c_int)
        res = func(pointer(i))
        self.assertEqual(res.contents.value, 12345678)
        self.assertEqual(res[0], 12345678)

    def test_change_pointers(self):
        dll = CDLL(_ctypes_test.__file__)
        func = dll._testfunc_p_p

        i = c_int(87654)
        func.restype = POINTER(c_int)
        func.argtypes = (POINTER(c_int),)

        res = func(pointer(i))
        self.assertEqual(res[0], 87654)
        self.assertEqual(res.contents.value, 87654)

        # C code: *res = 54345
        res[0] = 54345
        self.assertEqual(i.value, 54345)

        # C code:
        #   int x = 12321;
        #   res = &x
        x = c_int(12321)
        res.contents = x
        self.assertEqual(i.value, 54345)

        x.value = -99
        self.assertEqual(res.contents.value, -99)

    def test_callbacks_with_pointers(self):
        # a function type receiving a pointer
        PROTOTYPE = CFUNCTYPE(c_int, POINTER(c_int))

        self.result = []

        def func(arg):
            for i in range(10):
                self.result.append(arg[i])
            return 0
        callback = PROTOTYPE(func)

        dll = CDLL(_ctypes_test.__file__)
        # This function expects a function pointer,
        # and calls this with an integer pointer as parameter.
        # The int pointer points to a table containing the numbers 1..10
        doit = dll._testfunc_callback_with_pointer

        doit(callback)
        doit(callback)

    def test_basics(self):
        for ct, pt in zip(ctype_types, python_types):
            i = ct(42)
            p = pointer(i)
            self.assertIs(type(p.contents), ct)
            # p.contents is the same as p[0]

            with self.assertRaises(TypeError):
                del p[0]

    def test_from_address(self):
        a = array.array('i', [100, 200, 300, 400, 500])
        addr = a.buffer_info()[0]
        p = POINTER(POINTER(c_int))

    def test_other(self):
        class Table(Structure):
            _fields_ = [("a", c_int),
                        ("b", c_int),
                        ("c", c_int)]

        pt = pointer(Table(1, 2, 3))

        self.assertEqual(pt.contents.a, 1)
        self.assertEqual(pt.contents.b, 2)
        self.assertEqual(pt.contents.c, 3)

        pt.contents.c = 33

        del _pointer_type_cache[Table]

    def test_basic(self):
        p = pointer(c_int(42))
        # Although a pointer can be indexed, it has no length
        self.assertRaises(TypeError, len, p)
        self.assertEqual(p[0], 42)
        self.assertEqual(p[0:1], [42])
        self.assertEqual(p.contents.value, 42)

    def test_charpp(self):
        """Test that a character pointer-to-pointer is correctly passed"""
        dll = CDLL(_ctypes_test.__file__)
        func = dll._testfunc_c_p_p
        func.restype = c_char_p
        argv = (c_char_p * 2)()
        argc = c_int( 2 )
        argv[0] = b'hello'
        argv[1] = b'world'
        result = func( byref(argc), argv )
        self.assertEqual(result, b'world')

    def test_bug_1467852(self):
        # http://sourceforge.net/tracker/?func=detail&atid=532154&aid=1467852&group_id=71702
        x = c_int(5)
        dummy = []
        for i in range(32000):
            dummy.append(c_int(i))
        y = c_int(6)
        p = pointer(x)
        pp = pointer(p)
        q = pointer(y)
        pp[0] = q         # <==
        self.assertEqual(p[0], 6)
    def test_c_void_p(self):
        # http://sourceforge.net/tracker/?func=detail&aid=1518190&group_id=5470&atid=105470
        if sizeof(c_void_p) == 4:
            self.assertEqual(c_void_p(0xFFFFFFFF).value,
                                 c_void_p(-1).value)
            self.assertEqual(c_void_p(0xFFFFFFFFFFFFFFFF).value,
                                 c_void_p(-1).value)
        elif sizeof(c_void_p) == 8:
            self.assertEqual(c_void_p(0xFFFFFFFF).value,
                                 0xFFFFFFFF)
            self.assertEqual(c_void_p(0xFFFFFFFFFFFFFFFF).value,
                                 c_void_p(-1).value)
            self.assertEqual(c_void_p(0xFFFFFFFFFFFFFFFFFFFFFFFF).value,
                                 c_void_p(-1).value)

        self.assertRaises(TypeError, c_void_p, 3.14) # make sure floats are NOT accepted
        self.assertRaises(TypeError, c_void_p, object()) # nor other objects

    def test_pointers_bool(self):
        # NULL pointers have a boolean False value, non-NULL pointers True.
        self.assertEqual(bool(POINTER(c_int)()), False)
        self.assertEqual(bool(pointer(c_int())), True)

        self.assertEqual(bool(CFUNCTYPE(None)(0)), False)
        self.assertEqual(bool(CFUNCTYPE(None)(42)), True)

        # COM methods are boolean True:
        if sys.platform == "win32":
            mth = ctypes.WINFUNCTYPE(None)(42, "name", (), None)
            self.assertEqual(bool(mth), True)

    def test_pointer_type_name(self):
        LargeNamedType = type('T' * 2 ** 25, (Structure,), {})
        self.assertTrue(POINTER(LargeNamedType))

        # to not leak references, we must clean _pointer_type_cache
        del _pointer_type_cache[LargeNamedType]

    def test_pointer_type_str_name(self):
        large_string = 'T' * 2 ** 25
        P = POINTER(large_string)
        self.assertTrue(P)

        # to not leak references, we must clean _pointer_type_cache
        del _pointer_type_cache[id(P)]

    def test_abstract(self):
        self.assertRaises(TypeError, _Pointer.set_type, 42)


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