from _compat_pickle import (IMPORT_MAPPING, REVERSE_IMPORT_MAPPING,
                            NAME_MAPPING, REVERSE_NAME_MAPPING)
import builtins
import pickle
import io
import collections
import struct
import sys
import weakref

import unittest
from test import support

from test.pickletester import AbstractHookTests
from test.pickletester import AbstractUnpickleTests
from test.pickletester import AbstractPickleTests
from test.pickletester import AbstractPickleModuleTests
from test.pickletester import AbstractPersistentPicklerTests
from test.pickletester import AbstractIdentityPersistentPicklerTests
from test.pickletester import AbstractPicklerUnpicklerObjectTests
from test.pickletester import AbstractDispatchTableTests
from test.pickletester import AbstractCustomPicklerClass
from test.pickletester import BigmemPickleTests

try:
    import _pickle
    has_c_implementation = True
except ImportError:
    has_c_implementation = False


class PyPickleTests(AbstractPickleModuleTests):
    dump = staticmethod(pickle._dump)
    dumps = staticmethod(pickle._dumps)
    load = staticmethod(pickle._load)
    loads = staticmethod(pickle._loads)
    Pickler = pickle._Pickler
    Unpickler = pickle._Unpickler


class PyUnpicklerTests(AbstractUnpickleTests):

    unpickler = pickle._Unpickler
    bad_stack_errors = (IndexError,)
    truncated_errors = (pickle.UnpicklingError, EOFError,
                        AttributeError, ValueError,
                        struct.error, IndexError, ImportError)

    def loads(self, buf, **kwds):
        f = io.BytesIO(buf)
        u = self.unpickler(f, **kwds)
        return u.load()


class PyPicklerTests(AbstractPickleTests):

    pickler = pickle._Pickler
    unpickler = pickle._Unpickler

    def dumps(self, arg, proto=None, **kwargs):
        f = io.BytesIO()
        p = self.pickler(f, proto, **kwargs)
        p.dump(arg)
        f.seek(0)
        return bytes(f.read())

    def loads(self, buf, **kwds):
        f = io.BytesIO(buf)
        u = self.unpickler(f, **kwds)
        return u.load()


class InMemoryPickleTests(AbstractPickleTests, AbstractUnpickleTests,
                          BigmemPickleTests):

    bad_stack_errors = (pickle.UnpicklingError, IndexError)
    truncated_errors = (pickle.UnpicklingError, EOFError,
                        AttributeError, ValueError,
                        struct.error, IndexError, ImportError)

    def dumps(self, arg, protocol=None, **kwargs):
        return pickle.dumps(arg, protocol, **kwargs)

    def loads(self, buf, **kwds):
        return pickle.loads(buf, **kwds)

    test_framed_write_sizes_with_delayed_writer = None


class PersistentPicklerUnpicklerMixin(object):

    def dumps(self, arg, proto=None):
        class PersPickler(self.pickler):
            def persistent_id(subself, obj):
                return self.persistent_id(obj)
        f = io.BytesIO()
        p = PersPickler(f, proto)
        p.dump(arg)
        return f.getvalue()

    def loads(self, buf, **kwds):
        class PersUnpickler(self.unpickler):
            def persistent_load(subself, obj):
                return self.persistent_load(obj)
        f = io.BytesIO(buf)
        u = PersUnpickler(f, **kwds)
        return u.load()


class PyPersPicklerTests(AbstractPersistentPicklerTests,
                         PersistentPicklerUnpicklerMixin):

    pickler = pickle._Pickler
    unpickler = pickle._Unpickler


class PyIdPersPicklerTests(AbstractIdentityPersistentPicklerTests,
                           PersistentPicklerUnpicklerMixin):

    pickler = pickle._Pickler
    unpickler = pickle._Unpickler

    @support.cpython_only
    def test_pickler_reference_cycle(self):
        def check(Pickler):
            for proto in range(pickle.HIGHEST_PROTOCOL + 1):
                f = io.BytesIO()
                pickler = Pickler(f, proto)
                pickler.dump('abc')
                self.assertEqual(self.loads(f.getvalue()), 'abc')
            pickler = Pickler(io.BytesIO())
            self.assertEqual(pickler.persistent_id('def'), 'def')
            r = weakref.ref(pickler)
            del pickler
            self.assertIsNone(r())

        class PersPickler(self.pickler):
            def persistent_id(subself, obj):
                return obj
        check(PersPickler)

        class PersPickler(self.pickler):
            @classmethod
            def persistent_id(cls, obj):
                return obj
        check(PersPickler)

        class PersPickler(self.pickler):
            @staticmethod
            def persistent_id(obj):
                return obj
        check(PersPickler)

    @support.cpython_only
    def test_unpickler_reference_cycle(self):
        def check(Unpickler):
            for proto in range(pickle.HIGHEST_PROTOCOL + 1):
                unpickler = Unpickler(io.BytesIO(self.dumps('abc', proto)))
                self.assertEqual(unpickler.load(), 'abc')
            unpickler = Unpickler(io.BytesIO())
            self.assertEqual(unpickler.persistent_load('def'), 'def')
            r = weakref.ref(unpickler)
            del unpickler
            self.assertIsNone(r())

        class PersUnpickler(self.unpickler):
            def persistent_load(subself, pid):
                return pid
        check(PersUnpickler)

        class PersUnpickler(self.unpickler):
            @classmethod
            def persistent_load(cls, pid):
                return pid
        check(PersUnpickler)

        class PersUnpickler(self.unpickler):
            @staticmethod
            def persistent_load(pid):
                return pid
        check(PersUnpickler)


class PyPicklerUnpicklerObjectTests(AbstractPicklerUnpicklerObjectTests):

    pickler_class = pickle._Pickler
    unpickler_class = pickle._Unpickler


class PyDispatchTableTests(AbstractDispatchTableTests):

    pickler_class = pickle._Pickler

    def get_dispatch_table(self):
        return pickle.dispatch_table.copy()


class PyChainDispatchTableTests(AbstractDispatchTableTests):

    pickler_class = pickle._Pickler

    def get_dispatch_table(self):
        return collections.ChainMap({}, pickle.dispatch_table)


class PyPicklerHookTests(AbstractHookTests):
    class CustomPyPicklerClass(pickle._Pickler,
                               AbstractCustomPicklerClass):
        pass
    pickler_class = CustomPyPicklerClass


if has_c_implementation:
    class CPickleTests(AbstractPickleModuleTests):
        from _pickle import dump, dumps, load, loads, Pickler, Unpickler

    class CUnpicklerTests(PyUnpicklerTests):
        unpickler = _pickle.Unpickler
        bad_stack_errors = (pickle.UnpicklingError,)
        truncated_errors = (pickle.UnpicklingError,)

    class CPicklerTests(PyPicklerTests):
        pickler = _pickle.Pickler
        unpickler = _pickle.Unpickler

    class CPersPicklerTests(PyPersPicklerTests):
        pickler = _pickle.Pickler
        unpickler = _pickle.Unpickler

    class CIdPersPicklerTests(PyIdPersPicklerTests):
        pickler = _pickle.Pickler
        unpickler = _pickle.Unpickler

    class CDumpPickle_LoadPickle(PyPicklerTests):
        pickler = _pickle.Pickler
        unpickler = pickle._Unpickler

    class DumpPickle_CLoadPickle(PyPicklerTests):
        pickler = pickle._Pickler
        unpickler = _pickle.Unpickler

    class CPicklerUnpicklerObjectTests(AbstractPicklerUnpicklerObjectTests):
        pickler_class = _pickle.Pickler
        unpickler_class = _pickle.Unpickler

        def test_issue18339(self):
            unpickler = self.unpickler_class(io.BytesIO())
            with self.assertRaises(TypeError):
                unpickler.memo = object
            # used to cause a segfault
            with self.assertRaises(ValueError):
                unpickler.memo = {-1: None}
            unpickler.memo = {1: None}

    class CDispatchTableTests(AbstractDispatchTableTests):
        pickler_class = pickle.Pickler
        def get_dispatch_table(self):
            return pickle.dispatch_table.copy()

    class CChainDispatchTableTests(AbstractDispatchTableTests):
        pickler_class = pickle.Pickler
        def get_dispatch_table(self):
            return collections.ChainMap({}, pickle.dispatch_table)

    class CPicklerHookTests(AbstractHookTests):
        class CustomCPicklerClass(_pickle.Pickler, AbstractCustomPicklerClass):
            pass
        pickler_class = CustomCPicklerClass

    @support.cpython_only
    class SizeofTests(unittest.TestCase):
        check_sizeof = support.check_sizeof

        def test_pickler(self):
            basesize = support.calcobjsize('7P2n3i2n3i2P')
            p = _pickle.Pickler(io.BytesIO())
            self.assertEqual(object.__sizeof__(p), basesize)
            MT_size = struct.calcsize('3nP0n')
            ME_size = struct.calcsize('Pn0P')
            check = self.check_sizeof
            check(p, basesize +
                MT_size + 8 * ME_size +  # Minimal memo table size.
                sys.getsizeof(b'x'*4096))  # Minimal write buffer size.
            for i in range(6):
                p.dump(chr(i))
            check(p, basesize +
                MT_size + 32 * ME_size +  # Size of memo table required to
                                          # save references to 6 objects.
                0)  # Write buffer is cleared after every dump().

        def test_unpickler(self):
            basesize = support.calcobjsize('2P2n2P 2P2n2i5P 2P3n8P2n2i')
            unpickler = _pickle.Unpickler
            P = struct.calcsize('P')  # Size of memo table entry.
            n = struct.calcsize('n')  # Size of mark table entry.
            check = self.check_sizeof
            for encoding in 'ASCII', 'UTF-16', 'latin-1':
                for errors in 'strict', 'replace':
                    u = unpickler(io.BytesIO(),
                                  encoding=encoding, errors=errors)
                    self.assertEqual(object.__sizeof__(u), basesize)
                    check(u, basesize +
                             32 * P +  # Minimal memo table size.
                             len(encoding) + 1 + len(errors) + 1)

            stdsize = basesize + len('ASCII') + 1 + len('strict') + 1
            def check_unpickler(data, memo_size, marks_size):
                dump = pickle.dumps(data)
                u = unpickler(io.BytesIO(dump),
                              encoding='ASCII', errors='strict')
                u.load()
                check(u, stdsize + memo_size * P + marks_size * n)

            check_unpickler(0, 32, 0)
            # 20 is minimal non-empty mark stack size.
            check_unpickler([0] * 100, 32, 20)
            # 128 is memo table size required to save references to 100 objects.
            check_unpickler([chr(i) for i in range(100)], 128, 20)
            def recurse(deep):
                data = 0
                for i in range(deep):
                    data = [data, data]
                return data
            check_unpickler(recurse(0), 32, 0)
            check_unpickler(recurse(1), 32, 20)
            check_unpickler(recurse(20), 32, 20)
            check_unpickler(recurse(50), 64, 60)
            check_unpickler(recurse(100), 128, 140)

            u = unpickler(io.BytesIO(pickle.dumps('a', 0)),
                          encoding='ASCII', errors='strict')
            u.load()
            check(u, stdsize + 32 * P + 2 + 1)


ALT_IMPORT_MAPPING = {
    ('_elementtree', 'xml.etree.ElementTree'),
    ('cPickle', 'pickle'),
    ('StringIO', 'io'),
    ('cStringIO', 'io'),
}

ALT_NAME_MAPPING = {
    ('__builtin__', 'basestring', 'builtins', 'str'),
    ('exceptions', 'StandardError', 'builtins', 'Exception'),