Make circuit reordering atomic

src/db/repositories/circuit.repository.ts

@@ -137,6 +137,46 @@ export class CircuitRepository {
       .orderBy(asc(circuits.sortOrder), asc(circuits.equipmentIdentifier));
   }
 
+  updateSortOrdersSafely(sectionId: string, orderedCircuitIds: string[]) {
+    if (orderedCircuitIds.length === 0) {
+      return;
+    }
+    if (new Set(orderedCircuitIds).size !== orderedCircuitIds.length) {
+      throw new Error("Stromkreise dürfen in der Reihenfolge nicht mehrfach vorkommen.");
+    }
+
+    db.transaction((tx) => {
+      const sectionCircuits = tx
+        .select({ id: circuits.id })
+        .from(circuits)
+        .where(eq(circuits.sectionId, sectionId))
+        .all();
+      const sectionCircuitIds = new Set(sectionCircuits.map((circuit) => circuit.id));
+      if (
+        sectionCircuits.length !== orderedCircuitIds.length ||
+        orderedCircuitIds.some((circuitId) => !sectionCircuitIds.has(circuitId))
+      ) {
+        throw new Error("Die Reihenfolge muss alle Stromkreise des Bereichs enthalten.");
+      }
+
+      for (let index = 0; index < orderedCircuitIds.length; index += 1) {
+        const result = tx
+          .update(circuits)
+          .set({ sortOrder: (index + 1) * 10 })
+          .where(
+            and(
+              eq(circuits.sectionId, sectionId),
+              eq(circuits.id, orderedCircuitIds[index])
+            )
+          )
+          .run();
+        if (result.changes !== 1) {
+          throw new Error("Ein Stromkreis wurde vor Abschluss der Sortierung verändert.");
+        }
+      }
+    });
+  }
+
   async updateEquipmentIdentifiersSafely(
     circuitListId: string,
     updates: Array<{ id: string; equipmentIdentifier: string }>,