moment/harmonyqml/backend/model/list_model.py

444 lines
13 KiB
Python

import logging
import textwrap
from typing import (
Any, Callable, Dict, Iterable, List, Mapping, MutableSequence, Optional,
Sequence, Set, Tuple, Union
)
from PyQt5.QtCore import (
QAbstractListModel, QModelIndex, QObject, Qt, pyqtProperty, pyqtSignal,
pyqtSlot
)
from .list_item import ListItem
Index = Union[int, str]
NewItem = Union[ListItem, Mapping[str, Any], Sequence]
class _GetFail:
pass
class _PopFail:
pass
class ListModel(QAbstractListModel):
rolesSet = pyqtSignal()
changed = pyqtSignal()
countChanged = pyqtSignal(int)
def __init__(self,
initial_data: Optional[List[NewItem]] = None,
container: Callable[..., MutableSequence] = list,
default_factory: Optional[Callable[[str], ListItem]] = None,
parent: QObject = None) -> None:
super().__init__(parent)
self._data: MutableSequence[ListItem] = container()
self.default_factory = default_factory
if initial_data:
self.extend(initial_data)
def __repr__(self) -> str:
if not self._data:
return "\033[35m%s\033[0m()" % type(self).__name__
return "\033[35m%s\033[0m(\n%s\n)" % (
type(self).__name__,
textwrap.indent(
",\n".join((repr(item) for item in self._data)),
prefix = " " * 4,
)
)
def __contains__(self, index: Index) -> bool:
if isinstance(index, str):
try:
self.indexWhere(index)
return True
except ValueError:
return False
return index in self._data
def __getitem__(self, index: Index) -> ListItem:
return self.get(index)
def __setitem__(self, index: Index, value: NewItem) -> None:
self.set(index, value)
def __delitem__(self, index: Index) -> None:
self.remove(index)
def __len__(self) -> int:
return len(self._data)
def __iter__(self) -> Iterable[NewItem]:
return iter(self._data)
def __bool__(self) -> bool:
return bool(self._data)
@pyqtSlot(result=str)
def repr(self) -> str:
return self.__repr__()
@pyqtProperty("QStringList", notify=rolesSet)
def roles(self) -> Tuple[str, ...]:
return self._data[0].roles if self._data else () # type: ignore
@pyqtProperty("QVariant", notify=rolesSet)
def mainKey(self) -> Optional[str]:
return self._data[0].mainKey if self._data else None
def roleNumbers(self) -> Dict[str, int]:
return {name: Qt.UserRole + i
for i, name in enumerate(self.roles, 1)} \
if self._data else {}
def roleNames(self) -> Dict[int, bytes]:
return {Qt.UserRole + i: bytes(name, "utf-8")
for i, name in enumerate(self.roles, 1)} \
if self._data else {}
def data(self, index: QModelIndex, role: int = Qt.DisplayRole) -> Any:
if role <= Qt.UserRole:
return None
return getattr(self._data[index.row()],
str(self.roleNames()[role], "utf8"))
def rowCount(self, _: QModelIndex = QModelIndex()) -> int:
return len(self)
def _convert_new_value(self, value: NewItem) -> ListItem:
def convert() -> ListItem:
if self._data and isinstance(value, Mapping):
if not set(value.keys()) <= set(self.roles):
raise ValueError(
f"{value}: must have all these keys: {self.roles}"
)
return type(self._data[0])(**value)
if not self._data and isinstance(value, Mapping):
raise NotImplementedError("First item must be set from Python")
if self._data and isinstance(value, type(self._data[0])):
return value
if not self._data and isinstance(value, ListItem):
return value
raise TypeError("%r: must be mapping or %s" % (
value,
type(self._data[0]).__name__ if self._data else "ListItem"
))
value = convert()
value.setParent(self)
return value
@pyqtProperty(int, notify=countChanged)
def count(self) -> int:
return len(self)
@pyqtSlot("QVariant", result=int)
def indexWhere(self,
main_key_is_value: Any,
_can_use_default_factory: bool = True) -> int:
for i, item in enumerate(self._data):
if getattr(item, self.mainKey) == main_key_is_value:
return i
if _can_use_default_factory and self.default_factory:
return self.append(self.default_factory(main_key_is_value))
raise ValueError(
f"No item in model data with "
f"property {self.mainKey} is set to {main_key_is_value!r}."
)
@pyqtSlot(int, result="QVariant")
@pyqtSlot(str, result="QVariant")
@pyqtSlot(int, "QVariant", result="QVariant")
@pyqtSlot(str, "QVariant", result="QVariant")
def get(self, index: Index, default: Any = _GetFail()) -> ListItem:
try:
i_index: int = \
self.indexWhere(index, _can_use_default_factory=False) \
if isinstance(index, str) else index
return self._data[i_index]
except (ValueError, IndexError):
if isinstance(default, _GetFail):
if self.default_factory and isinstance(index, str):
item = self.default_factory(index)
self.append(item)
return item
raise
return default
@pyqtSlot(int, "QVariantMap", result=int)
def insert(self, index: int, value: NewItem) -> int:
value = self._convert_new_value(value)
try:
present_index = self.indexWhere(
main_key_is_value = getattr(value, self.mainKey),
_can_use_default_factory = False
)
except (TypeError, ValueError): # TypeError = no items in model
pass
else:
logging.warning(
"Duplicate mainKey %r in model - present: %r, inserting: %r",
self.mainKey,
self[present_index],
value
)
self.beginInsertRows(QModelIndex(), index, index)
had_data = bool(self._data)
self._data.insert(index, value)
if not had_data:
self.rolesSet.emit()
self.endInsertRows()
self.countChanged.emit(len(self))
self.changed.emit()
return index
@pyqtSlot("QVariantMap", result=int)
def append(self, value: NewItem) -> int:
return self.insert(len(self), value)
@pyqtSlot(list)
def extend(self, values: Iterable[NewItem]) -> None:
for val in values:
self.append(val)
@pyqtSlot(list)
@pyqtSlot(list, bool)
def updateAll(self, items: Sequence[NewItem], delete: bool = False
) -> None:
items_: List[ListItem] = [self._convert_new_value(i) for i in items]
if delete:
present_item: ListItem
for i, present_item in enumerate(self):
present_item_key = getattr(present_item, self.mainKey)
# If this present item is in the update items, based on mainKey
for update_item in items_:
if present_item_key == getattr(update_item, self.mainKey):
break
else:
del self[i]
for item in items_:
self.upsert(
where_main_key_is = getattr(item, item.mainKey),
update_with = item
)
@pyqtSlot(int, "QVariantMap", result=int)
@pyqtSlot(int, "QVariantMap", "QStringList", result=int)
@pyqtSlot(str, "QVariantMap", result=int)
@pyqtSlot(str, "QVariantMap", "QStringList", result=int)
def updateItem(self,
index: Index,
value: NewItem,
no_update: Sequence[str] = ()) -> int:
value = self._convert_new_value(value)
i_index: int = self.indexWhere(index, _can_use_default_factory=False) \
if isinstance(index, str) else index
to_update = self[i_index]
updated_roles: Set[int] = set()
for role_name, role_num in self.roleNumbers().items():
if role_name not in no_update:
old_value = getattr(to_update, role_name)
new_value = getattr(value, role_name)
if old_value != new_value:
try:
setattr(to_update, role_name, new_value)
except AttributeError: # constant/not settable
pass
else:
updated_roles.add(role_num)
if updated_roles:
qidx = QAbstractListModel.index(self, i_index, 0)
self.dataChanged.emit(qidx, qidx, updated_roles)
self.changed.emit()
return i_index
@pyqtSlot(str, "QVariantMap")
@pyqtSlot(str, "QVariantMap", int)
@pyqtSlot(str, "QVariantMap", int, int)
@pyqtSlot(str, "QVariantMap", int, int, "QStringList")
def upsert(self,
where_main_key_is: Any,
update_with: NewItem,
new_index_if_insert: Optional[int] = None,
new_index_if_update: Optional[int] = None,
no_update: Sequence[str] = ()) -> None:
try:
index = self.updateItem(
where_main_key_is, update_with, no_update
)
except (IndexError, ValueError):
self.insert(new_index_if_insert or len(self), update_with)
else:
if new_index_if_update:
self.move(index, new_index_if_update)
@pyqtSlot(int, list)
@pyqtSlot(str, list)
def set(self, index: Index, value: NewItem) -> None:
i_index: int = self.indexWhere(index) \
if isinstance(index, str) else index
qidx = QAbstractListModel.index(self, i_index, 0)
value = self._convert_new_value(value)
self._data[i_index] = value
self.dataChanged.emit(qidx, qidx, self.roleNames())
self.changed.emit()
@pyqtSlot(int, str, "QVariant")
@pyqtSlot(str, str, "QVariant")
def setProperty(self, index: Index, prop: str, value: Any) -> None:
i_index: int = self.indexWhere(index) \
if isinstance(index, str) else index
if getattr(self[i_index], prop) != value:
setattr(self[i_index], prop, value)
qidx = QAbstractListModel.index(self, i_index, 0)
self.dataChanged.emit(qidx, qidx, (self.roleNumbers()[prop],))
self.changed.emit()
@pyqtSlot(int, int)
@pyqtSlot(int, int, int)
@pyqtSlot(str, int)
@pyqtSlot(str, int, int)
def move(self, from_: Index, to: int, n: int = 1) -> None:
# pylint: disable=invalid-name
i_from: int = self.indexWhere(from_) \
if isinstance(from_, str) else from_
qlast = i_from + n - 1
if (n <= 0) or (i_from == to) or (qlast == to) or \
not (len(self) > qlast >= 0) or \
not len(self) >= to >= 0:
return
qidx = QModelIndex()
qto = min(len(self), to + n if to > i_from else to)
# print(f"self.beginMoveRows(qidx, {i_from}, {qlast}, qidx, {qto})")
valid = self.beginMoveRows(qidx, i_from, qlast, qidx, qto)
if not valid:
logging.warning("Invalid move operation - %r", locals())
return
last = i_from + n
cut = self._data[i_from:last]
del self._data[i_from:last]
self._data[to:to] = cut
self.endMoveRows()
self.changed.emit()
@pyqtSlot(int)
@pyqtSlot(str)
def remove(self, index: Index) -> None:
i_index: int = self.indexWhere(index) \
if isinstance(index, str) else index
self.beginRemoveRows(QModelIndex(), i_index, i_index)
del self._data[i_index]
self.endRemoveRows()
self.countChanged.emit(len(self))
self.changed.emit()
@pyqtSlot(int, result="QVariant")
@pyqtSlot(str, result="QVariant")
def pop(self, index: Index, default: Any = _PopFail()) -> ListItem:
try:
i_index: int = self.indexWhere(index) \
if isinstance(index, str) else index
item = self[i_index]
except (ValueError, IndexError):
if isinstance(default, _PopFail):
raise
return default
self.beginRemoveRows(QModelIndex(), i_index, i_index)
del self._data[i_index]
self.endRemoveRows()
self.countChanged.emit(len(self))
self.changed.emit()
return item
@pyqtSlot()
def clear(self) -> None:
if not self._data:
return
# Reimplemented for performance reasons (begin/endRemoveRows)
self.beginRemoveRows(QModelIndex(), 0, len(self))
self._data.clear()
self.endRemoveRows()
self.countChanged.emit(len(self))
self.changed.emit()