from __future__ import annotations from collections import defaultdict from typing import TypeVar, Generic, Dict, Optional, Iterable, List, Iterator, Tuple, Generator, Union, Any from .parents import OuterProxy from ..utils import object_trace T = TypeVar('T', bound=OuterProxy) class Collection(Generic[T]): __is_collection__ = True _data: List[T] _indexed_values: Dict[str, set] _indexed_to_objects: Dict[any, list] shallow_list = property(fget=lambda self: self.data) def __init__( self, data: Optional[Iterable[T]] = None, sync_on_append: Dict[str, Collection] = None, append_object_to_attribute: Dict[str, T] = None, extend_object_to_attribute: Dict[str, Collection] = None, ) -> None: self._collection_for: dict = dict() self._contains_ids = set() self._data = [] # List of collection attributes that should be modified on append # Key: collection attribute (str) of appended element # Value: main collection to sync to self.append_object_to_attribute: Dict[str, T] = append_object_to_attribute or {} self.extend_object_to_attribute: Dict[str, Collection[T]] = extend_object_to_attribute or {} self.sync_on_append: Dict[str, Collection] = sync_on_append or {} self._id_to_index_values: Dict[int, set] = defaultdict(set) # This is to cleanly unmap previously mapped items by their id self._indexed_from_id: Dict[int, Dict[str, Any]] = defaultdict(dict) # this is to keep track and look up the actual objects self._indexed_values: Dict[str, Dict[Any, T]] = defaultdict(dict) self.extend(data) def __repr__(self) -> str: return f"Collection({id(self)})" def _map_element(self, __object: T, from_map: bool = False): self._unmap_element(__object.id) self._indexed_from_id[__object.id]["id"] = __object.id self._indexed_values["id"][__object.id] = __object for name, value in __object.indexing_values: if value is None or value == __object._inner._default_values.get(name): continue self._indexed_values[name][value] = __object self._indexed_from_id[__object.id][name] = value def _unmap_element(self, __object: Union[T, int]): obj_id = __object.id if isinstance(__object, OuterProxy) else __object if obj_id not in self._indexed_from_id: return for name, value in self._indexed_from_id[obj_id].items(): if value in self._indexed_values[name]: del self._indexed_values[name][value] del self._indexed_from_id[obj_id] def _find_object(self, __object: T) -> Optional[T]: for name, value in __object.indexing_values: if value in self._indexed_values[name]: return self._indexed_values[name][value] def append(self, __object: Optional[T], already_is_parent: bool = False, from_map: bool = False): """ If an object, that represents the same entity exists in a relevant collection, merge into this object. (and remap) Else append to this collection. :param __object: :param already_is_parent: :param from_map: :return: """ if __object is None: return existing_object = self._find_object(__object) if existing_object is None: # append self._data.append(__object) self._map_element(__object) for collection_attribute, child_collection in self.extend_object_to_attribute.items(): __object.__getattribute__(collection_attribute).extend(child_collection) for attribute, new_object in self.append_object_to_attribute.items(): __object.__getattribute__(attribute).append(new_object) # only modify collections if the object actually has been appended for attribute, a in self.sync_on_append.items(): b = __object.__getattribute__(attribute) object_trace(f"Syncing [{a}{id(a)}] = [{b}{id(b)}]") data_to_extend = b.data a._collection_for.update(b._collection_for) for synced_with, key in b._collection_for.items(): synced_with.__setattr__(key, a) a.extend(data_to_extend) else: # merge only if the two objects are not the same if existing_object.id == __object.id: return old_id = existing_object.id existing_object.merge(__object) if existing_object.id != old_id: self._unmap_element(old_id) self._map_element(existing_object) def extend(self, __iterable: Optional[Generator[T, None, None]]): if __iterable is None: return for __object in __iterable: self.append(__object) @property def data(self) -> List[T]: return list(self.__iter__()) def __len__(self) -> int: return len(self._data) @property def empty(self) -> bool: return self.__len__() <= 0 def __iter__(self) -> Iterator[T]: yield from self._data def __merge__(self, __other: Collection, override: bool = False): self.extend(__other) def __getitem__(self, item: int): return self._data[item] def get(self, item: int, default = None): if item >= len(self._data): return default return self._data[item]