import weakref
from mongoengine.common import _import_class

__all__ = ("BaseDict", "BaseList")


class BaseDict(dict):
    """A special dict so we can watch any changes
    """

    _dereferenced = False
    _instance = None
    _name = None

    def __init__(self, dict_items, instance, name):
        Document = _import_class('Document')
        EmbeddedDocument = _import_class('EmbeddedDocument')

        if isinstance(instance, (Document, EmbeddedDocument)):
            self._instance = weakref.proxy(instance)
        self._name = name
        return super(BaseDict, self).__init__(dict_items)

    def __getitem__(self, *args, **kwargs):
        value = super(BaseDict, self).__getitem__(*args, **kwargs)

        EmbeddedDocument = _import_class('EmbeddedDocument')
        if isinstance(value, EmbeddedDocument) and value._instance is None:
            value._instance = self._instance
        return value

    def __setitem__(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseDict, self).__setitem__(*args, **kwargs)

    def __delete__(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseDict, self).__delete__(*args, **kwargs)

    def __delitem__(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseDict, self).__delitem__(*args, **kwargs)

    def __delattr__(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseDict, self).__delattr__(*args, **kwargs)

    def __getstate__(self):
        self.instance = None
        self._dereferenced = False
        return self

    def __setstate__(self, state):
        self = state
        return self

    def clear(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseDict, self).clear(*args, **kwargs)

    def pop(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseDict, self).pop(*args, **kwargs)

    def popitem(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseDict, self).popitem(*args, **kwargs)

    def update(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseDict, self).update(*args, **kwargs)

    def _mark_as_changed(self):
        if hasattr(self._instance, '_mark_as_changed'):
            self._instance._mark_as_changed(self._name)


class BaseList(list):
    """A special list so we can watch any changes
    """

    _dereferenced = False
    _instance = None
    _name = None

    def __init__(self, list_items, instance, name):
        Document = _import_class('Document')
        EmbeddedDocument = _import_class('EmbeddedDocument')

        if isinstance(instance, (Document, EmbeddedDocument)):
            self._instance = weakref.proxy(instance)
        self._name = name
        return super(BaseList, self).__init__(list_items)

    def __getitem__(self, *args, **kwargs):
        value = super(BaseList, self).__getitem__(*args, **kwargs)

        EmbeddedDocument = _import_class('EmbeddedDocument')
        if isinstance(value, EmbeddedDocument) and value._instance is None:
            value._instance = self._instance
        return value

    def __setitem__(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseList, self).__setitem__(*args, **kwargs)

    def __delitem__(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseList, self).__delitem__(*args, **kwargs)

    def __getstate__(self):
        self.instance = None
        self._dereferenced = False
        return self

    def __setstate__(self, state):
        self = state
        return self

    def append(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseList, self).append(*args, **kwargs)

    def extend(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseList, self).extend(*args, **kwargs)

    def insert(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseList, self).insert(*args, **kwargs)

    def pop(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseList, self).pop(*args, **kwargs)

    def remove(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseList, self).remove(*args, **kwargs)

    def reverse(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseList, self).reverse(*args, **kwargs)

    def sort(self, *args, **kwargs):
        self._mark_as_changed()
        return super(BaseList, self).sort(*args, **kwargs)

    def _mark_as_changed(self):
        if hasattr(self._instance, '_mark_as_changed'):
            self._instance._mark_as_changed(self._name)