# -*- coding: utf-8 -*-
from collections import MutableMapping
import random


class SafeDict(dict, MutableMapping):

    def __init__(self, *args, **kwds):
        dict.__init__(self)
        self._prefix = str(random.getrandbits(64))
        self.update(*args, **kwds)

    def clear(self):
        dict.clear(self)
        self._prefix = str(random.getrandbits(64))

    def _safe_key(self, key):
        return self._prefix + repr(key), key

    def __getitem__(self, key):
        try:
            return dict.__getitem__(self, self._safe_key(key))
        except KeyError as e:
            e.args = (key,)
            raise e

    def __setitem__(self, key, value):
        dict.__setitem__(self, self._safe_key(key), value)

    def __delitem__(self, key):
        try:
            dict.__delitem__(self, self._safe_key(key))
        except KeyError as e:
            e.args = (key,)
            raise e

    def __iter__(self):
        for skey, key in dict.__iter__(self):
            yield key

    def __contains__(self, key):
        return dict.__contains__(self, self._safe_key(key))

    setdefault = MutableMapping.setdefault
    update = MutableMapping.update
    pop = MutableMapping.pop
    popitem = MutableMapping.popitem
    keys = MutableMapping.keys
    values = MutableMapping.values
    items = MutableMapping.items

    def __repr__(self):
        return '{%s}' % ', '.join('%s: %s' % (repr(k), repr(v))
            for k, v in self.items())

    def copy(self):
        return self.__class__(self)

    @classmethod
    def fromkeys(cls, iterable, value=None):
        d = cls()
        for key in iterable:
            d[key] = value
        return d

    def __eq__(self, other):
        return all(k in other and other[k] == v for k, v in self.items()) and \
            all(k in self and self[k] == v for k, v in other.items())

    def __ne__(self, other):
        return not self == other