X-Git-Url: https://plomlompom.com/repos/berlin_corona.txt?a=blobdiff_plain;f=plomtask%2Fconditions.py;h=629510af868ae401c609b2c9307fa21f9c732c23;hb=9ad40c43627334d7294c07bf55d196dd6760cfde;hp=a45260092fdc6c75a94846eb0893b775eb9316dd;hpb=ee18435127ad396c24dbee2c7efcdbe6810d5a91;p=plomtask

diff --git a/plomtask/conditions.py b/plomtask/conditions.py
index a452600..629510a 100644
--- a/plomtask/conditions.py
+++ b/plomtask/conditions.py
@@ -3,7 +3,8 @@ from __future__ import annotations
 from typing import Any
 from sqlite3 import Row
 from plomtask.db import DatabaseConnection, BaseModel
-from plomtask.misc import VersionedAttribute
+from plomtask.versioned_attributes import VersionedAttribute
+from plomtask.exceptions import HandledException
 
 
 class Condition(BaseModel[int]):
@@ -18,6 +19,11 @@ class Condition(BaseModel[int]):
         self.description = VersionedAttribute(self, 'condition_descriptions',
                                               '')
 
+    def __lt__(self, other: Condition) -> bool:
+        assert isinstance(self.id_, int)
+        assert isinstance(other.id_, int)
+        return self.id_ < other.id_
+
     @classmethod
     def from_table_row(cls, db_conn: DatabaseConnection,
                        row: Row | list[Any]) -> Condition:
@@ -35,6 +41,23 @@ class Condition(BaseModel[int]):
         self.title.save(db_conn)
         self.description.save(db_conn)
 
+    def remove(self, db_conn: DatabaseConnection) -> None:
+        """Remove from DB, with VersionedAttributes.
+
+        Checks for Todos and Processes that depend on Condition, prohibits
+        deletion if found.
+        """
+        if self.id_ is None:
+            raise HandledException('cannot remove unsaved item')
+        for item in ('process', 'todo'):
+            for attr in ('conditions', 'enables', 'disables'):
+                table_name = f'{item}_{attr}'
+                for _ in db_conn.row_where(table_name, 'condition', self.id_):
+                    raise HandledException('cannot remove Condition in use')
+        db_conn.delete_where('condition_titles', 'parent', self.id_)
+        db_conn.delete_where('condition_descriptions', 'parent', self.id_)
+        super().remove(db_conn)
+
 
 class ConditionsRelations:
     """Methods for handling relations to Conditions, for Todo and Process."""