+ @staticmethod
+ def _x_ablers_for_at(db_conn: DatabaseConnection, name: str,
+ cond: Condition, date: str) -> list[Todo]:
+ """Collect all Todos of day that [name] condition."""
+ assert isinstance(cond.id_, int)
+ x_ablers = []
+ table = f'todo_{name}'
+ for id_ in db_conn.column_where(table, 'todo', 'condition', cond.id_):
+ todo = Todo.by_id(db_conn, id_)
+ if todo.date == date:
+ x_ablers += [todo]
+ return x_ablers
+
+ @classmethod
+ def enablers_for_at(cls, db_conn: DatabaseConnection,
+ condition: Condition, date: str) -> list[Todo]:
+ """Collect all Todos of day that enable condition."""
+ return cls._x_ablers_for_at(db_conn, 'enables', condition, date)
+
+ @classmethod
+ def disablers_for_at(cls, db_conn: DatabaseConnection,
+ condition: Condition, date: str) -> list[Todo]:
+ """Collect all Todos of day that disable condition."""
+ return cls._x_ablers_for_at(db_conn, 'disables', condition, date)
+
+ @property
+ def is_doable(self) -> bool:
+ """Decide whether .is_done settable based on children, Conditions."""
+ for child in self.children:
+ if not child.is_done:
+ return False
+ for condition in self.conditions:
+ if not condition.is_active:
+ return False
+ return True
+
+ @property
+ def process_id(self) -> int | str | None:
+ """Return ID of tasked Process."""
+ return self.process.id_
+
+ @property
+ def unsatisfied_dependencies(self) -> list[int]:
+ """Return Process IDs of .process.explicit_steps not in .children."""
+ unsatisfied = [s.step_process_id for s in self.process.explicit_steps
+ if s.parent_step_id is None]
+ for child_process_id in [c.process.id_ for c in self.children]:
+ if child_process_id in unsatisfied:
+ unsatisfied.remove(child_process_id)
+ return unsatisfied
+
+ @property
+ def is_done(self) -> bool:
+ """Wrapper around self._is_done so we can control its setter."""
+ return self._is_done
+
+ @is_done.setter
+ def is_done(self, value: bool) -> None:
+ if value != self.is_done and not self.is_doable:
+ raise BadFormatException('cannot change doneness of undoable Todo')
+ if self._is_done != value:
+ self._is_done = value
+ if value is True:
+ for condition in self.enables:
+ condition.is_active = True
+ for condition in self.disables:
+ condition.is_active = False
+
+ def adopt_from(self, todos: list[Todo]) -> None:
+ """As far as possible, fill unsatisfied dependencies from todos."""
+ for process_id in self.unsatisfied_dependencies:
+ for todo in [t for t in todos if t.process.id_ == process_id
+ and t not in self.children]:
+ self.add_child(todo)
+ break
+
+ def make_missing_children(self, db_conn: DatabaseConnection) -> None:
+ """Fill unsatisfied dependencies with new Todos."""
+ for process_id in self.unsatisfied_dependencies:
+ process = Process.by_id(db_conn, process_id)
+ todo = self.__class__(None, process, False, self.date)
+ todo.save(db_conn)
+ self.add_child(todo)
+
+ def get_step_tree(self, seen_todos: set[int],
+ seen_conditions: set[int]) -> TodoStepsNode:
+ """Return tree of depended-on Todos and Conditions."""
+
+ def make_node(step: Todo | Condition) -> TodoStepsNode:
+ assert isinstance(step.id_, int)
+ is_todo = isinstance(step, Todo)
+ children = []
+ if is_todo:
+ assert isinstance(step, Todo)
+ seen = step.id_ in seen_todos
+ seen_todos.add(step.id_)
+ potentially_enabled = set()
+ for child in step.children:
+ for condition in child.enables:
+ potentially_enabled.add(condition)
+ children += [make_node(child)]
+ for condition in [c for c in step.conditions
+ if (not c.is_active)
+ and (c not in potentially_enabled)]:
+ children += [make_node(condition)]
+ else:
+ seen = step.id_ in seen_conditions
+ seen_conditions.add(step.id_)
+ return TodoStepsNode(step, is_todo, children, seen)
+
+ node = make_node(self)
+ return node
+
+ def add_child(self, child: Todo) -> None:
+ """Add child to self.children, avoid recursion, update parenthoods."""
+
+ def walk_steps(node: Todo) -> None:
+ if node.id_ == self.id_:
+ raise BadFormatException('bad child choice causes recursion')
+ for child in node.children:
+ walk_steps(child)
+
+ if self.id_ is None:
+ raise HandledException('Can only add children to saved Todos.')
+ if child.id_ is None:
+ raise HandledException('Can only add saved children to Todos.')
+ if child in self.children:
+ raise BadFormatException('cannot adopt same child twice')
+ walk_steps(child)
+ self.children += [child]
+ child.parents += [self]
+
+ def remove_child(self, child: Todo) -> None:
+ """Remove child from self.children, update counter relations."""
+ if child not in self.children:
+ raise HandledException('Cannot remove un-parented child.')
+ self.children.remove(child)
+ child.parents.remove(self)
+