add init validation on recurrence

dooit/api/todo.py

@@ -2,7 +2,7 @@
 from datetime import datetime, timedelta
 from typing import List
 from sqlalchemy import ForeignKey, select, nulls_last
-from sqlalchemy.orm import Mapped, mapped_column, relationship
+from sqlalchemy.orm import Mapped, mapped_column, relationship, validates
 from .model import DooitModel
 from .manager import manager
 
@@ -47,6 +47,13 @@ class Todo(DooitModel):
         order_by=order_index,
     )
 
+    @validates("recurrence")
+    def validate_pending(self, key, value):
+        if value is not None:
+            self.pending = True
+
+        return value
+
     @classmethod
     def from_id(cls, _id: str) -> "Todo":
         _id = _id.lstrip("Todo_")