Make single row moves atomic

docs/circuit-list-editor-interactions.md

@@ -75,6 +75,7 @@ Intent is separated by drag source type:
   - drop to placeholder -> create new target circuit and move row(s)
   - crossing a section boundary requires explicit confirmation
   - phase type, category, linked project device and local row values remain unchanged
+  - target creation, row assignments and reserve-state updates use one SQLite transaction
 - circuit drag (BMK handle):
   - reorder circuits inside same section only
   - cross-section reorder is rejected
@@ -125,4 +126,3 @@ Current limitations:
 
 - session-local only
 - no persisted history across browser reload
-- some multi-step backend flows are not fully transaction-hardened end-to-end

docs/circuit-list-editor-known-limitations.md

@@ -5,7 +5,6 @@
 - No global cross-project device library workflow is implemented yet.
 - Final electrical sizing logic is not implemented yet.
 - No full norm-compliant voltage-drop and protection-dimensioning calculation flow yet.
-- Bulk device-row move flow is command-based but not fully transaction-hardened end-to-end across all affected circuits.
 - Sorting is view-only until users explicitly apply sorted order.
 - Cross-section circuit drag-reorder is intentionally blocked.
 - Legacy consumer and circuit-first paths coexist; migration is transitional and still requires operational discipline.

src/db/repositories/circuit-device-row.repository.ts

@@ -26,6 +26,18 @@ export interface CircuitDeviceRowUpdateInput {
   overriddenFields?: string;
 }
 
+export interface CircuitDeviceRowsBulkMoveInput {
+  rows: Array<{ id: string; expectedCircuitId: string }>;
+  targetCircuitId?: string;
+  createTargetCircuit?: {
+    circuitListId: string;
+    sectionId: string;
+    equipmentIdentifier: string;
+    displayName: string;
+    sortOrder: number;
+  };
+}
+
 function toUpdateValues(input: CircuitDeviceRowUpdateInput) {
   return {
     linkedProjectDeviceId: input.linkedProjectDeviceId ?? null,
@@ -259,4 +271,138 @@ export class CircuitDeviceRowRepository {
       })
       .where(eq(circuitDeviceRows.id, rowId));
   }
+
+  moveRowsTransactional(input: CircuitDeviceRowsBulkMoveInput) {
+    if (input.rows.length === 0) {
+      throw new Error("Keine Gerätezeilen zum Verschieben angegeben.");
+    }
+    if (Boolean(input.targetCircuitId) === Boolean(input.createTargetCircuit)) {
+      throw new Error("Für die Mehrfachverschiebung muss genau ein Ziel angegeben werden.");
+    }
+
+    const rowIds = input.rows.map((row) => row.id);
+    if (new Set(rowIds).size !== rowIds.length) {
+      throw new Error("Gerätezeilen dürfen nicht mehrfach ausgewählt sein.");
+    }
+
+    const createdCircuitId = input.createTargetCircuit ? crypto.randomUUID() : undefined;
+    const targetCircuitId = input.targetCircuitId ?? createdCircuitId!;
+
+    // better-sqlite3 transactions must remain synchronous. Every row assignment,
+    // reserve-state update and optional target creation is committed or rolled back
+    // as one operation.
+    db.transaction((tx) => {
+      const persistedRows = tx
+        .select({ id: circuitDeviceRows.id, circuitId: circuitDeviceRows.circuitId })
+        .from(circuitDeviceRows)
+        .where(inArray(circuitDeviceRows.id, rowIds))
+        .all();
+      if (persistedRows.length !== input.rows.length) {
+        throw new Error("Eine oder mehrere Gerätezeilen sind ungültig.");
+      }
+
+      const persistedRowsById = new Map(persistedRows.map((row) => [row.id, row]));
+      for (const expectedRow of input.rows) {
+        if (persistedRowsById.get(expectedRow.id)?.circuitId !== expectedRow.expectedCircuitId) {
+          throw new Error("Eine Gerätezeile wurde vor Abschluss der Verschiebung verändert.");
+        }
+      }
+
+      let targetCircuit: { id: string; circuitListId: string };
+      if (input.createTargetCircuit) {
+        tx
+          .insert(circuits)
+          .values({
+            id: targetCircuitId,
+            circuitListId: input.createTargetCircuit.circuitListId,
+            sectionId: input.createTargetCircuit.sectionId,
+            equipmentIdentifier: input.createTargetCircuit.equipmentIdentifier,
+            displayName: input.createTargetCircuit.displayName,
+            sortOrder: input.createTargetCircuit.sortOrder,
+            isReserve: 0,
+          })
+          .run();
+        targetCircuit = {
+          id: targetCircuitId,
+          circuitListId: input.createTargetCircuit.circuitListId,
+        };
+      } else {
+        const [persistedTargetCircuit] = tx
+          .select({ id: circuits.id, circuitListId: circuits.circuitListId })
+          .from(circuits)
+          .where(eq(circuits.id, targetCircuitId))
+          .limit(1)
+          .all();
+        if (!persistedTargetCircuit) {
+          throw new Error("Der Zielstromkreis ist ungültig.");
+        }
+        targetCircuit = persistedTargetCircuit;
+      }
+
+      const sourceCircuitIds = [...new Set(input.rows.map((row) => row.expectedCircuitId))];
+      const sourceCircuits = tx
+        .select({ id: circuits.id, circuitListId: circuits.circuitListId })
+        .from(circuits)
+        .where(inArray(circuits.id, sourceCircuitIds))
+        .all();
+      if (sourceCircuits.length !== sourceCircuitIds.length) {
+        throw new Error("Einer oder mehrere Quellstromkreise sind ungültig.");
+      }
+      if (sourceCircuits.some((circuit) => circuit.circuitListId !== targetCircuit.circuitListId)) {
+        throw new Error("Alle verschobenen Zeilen müssen zur Stromkreisliste des Ziels gehören.");
+      }
+
+      const movedRowIdSet = new Set(rowIds);
+      const retainedTargetRows = tx
+        .select({ id: circuitDeviceRows.id, sortOrder: circuitDeviceRows.sortOrder })
+        .from(circuitDeviceRows)
+        .where(eq(circuitDeviceRows.circuitId, targetCircuitId))
+        .all()
+        .filter((row) => !movedRowIdSet.has(row.id));
+      const lastTargetSortOrder = retainedTargetRows.reduce(
+        (highest, row) => Math.max(highest, row.sortOrder),
+        0
+      );
+
+      for (let index = 0; index < input.rows.length; index += 1) {
+        const row = input.rows[index];
+        const result = tx
+          .update(circuitDeviceRows)
+          .set({
+            circuitId: targetCircuitId,
+            sortOrder: lastTargetSortOrder + (index + 1) * 10,
+          })
+          .where(
+            and(
+              eq(circuitDeviceRows.id, row.id),
+              eq(circuitDeviceRows.circuitId, row.expectedCircuitId)
+            )
+          )
+          .run();
+        if (result.changes !== 1) {
+          throw new Error("Eine Gerätezeile wurde vor Abschluss der Verschiebung verändert.");
+        }
+      }
+
+      for (const sourceCircuitId of sourceCircuitIds) {
+        const remainingRows = tx
+          .select({ id: circuitDeviceRows.id })
+          .from(circuitDeviceRows)
+          .where(eq(circuitDeviceRows.circuitId, sourceCircuitId))
+          .all();
+        tx
+          .update(circuits)
+          .set({ isReserve: remainingRows.length === 0 ? 1 : 0 })
+          .where(eq(circuits.id, sourceCircuitId))
+          .run();
+      }
+      tx.update(circuits).set({ isReserve: 0 }).where(eq(circuits.id, targetCircuitId)).run();
+    });
+
+    return {
+      movedRowIds: rowIds,
+      targetCircuitId,
+      createdCircuitId,
+    };
+  }
 }

src/domain/services/circuit-write.service.ts

@@ -316,7 +316,18 @@ export class CircuitWriteService {
       throw new Error("Invalid target circuit id.");
     }
 
-    // Placeholder-target move creates a new circuit explicitly; no implicit renumbering of others.
+    let createTargetCircuit:
+      | {
+          circuitListId: string;
+          sectionId: string;
+          equipmentIdentifier: string;
+          displayName: string;
+          sortOrder: number;
+        }
+      | undefined;
+
+    // Placeholder-target move prepares a new circuit explicitly. Its creation and
+    // the row assignment are committed together without renumbering other circuits.
     if (!targetCircuit) {
       if (!input.targetSectionId || !input.createNewCircuit) {
         throw new Error("Invalid move target.");
@@ -326,76 +337,27 @@ export class CircuitWriteService {
       const sectionCircuits = await this.circuitRepository.listBySection(section.id);
       const nextSortOrder =
         sectionCircuits.length > 0 ? Math.max(...sectionCircuits.map((circuit) => circuit.sortOrder)) + 10 : 10;
-      const createdId = await this.circuitRepository.create({
+      createTargetCircuit = {
         circuitListId: sourceCircuit.circuitListId,
         sectionId: section.id,
         equipmentIdentifier: nextIdentifier,
-        displayName: "New circuit",
+        displayName: "Neuer Stromkreis",
         sortOrder: nextSortOrder,
-        isReserve: false,
-      });
-      targetCircuit = await this.circuitRepository.findById(createdId);
-      if (!targetCircuit) {
-        throw new Error("Failed to create target circuit.");
-      }
+      };
     }
 
-    if (targetCircuit.circuitListId !== sourceCircuit.circuitListId) {
+    if (targetCircuit && targetCircuit.circuitListId !== sourceCircuit.circuitListId) {
       throw new Error("Target circuit does not belong to same circuit list.");
     }
-    if (targetCircuit.id === sourceCircuit.id) {
+    if (targetCircuit?.id === sourceCircuit.id) {
       return this.deviceRowRepository.findById(rowId);
     }
 
-    const targetCount = await this.deviceRowRepository.countByCircuit(targetCircuit.id);
-    await this.deviceRowRepository.moveToCircuit(rowId, targetCircuit.id, (targetCount + 1) * 10);
-
-    const sourceRemaining = await this.deviceRowRepository.countByCircuit(sourceCircuit.id);
-    // Source circuit becomes reserve when all rows are moved away.
-    if (sourceRemaining === 0) {
-      await this.circuitRepository.update(sourceCircuit.id, {
-        sectionId: sourceCircuit.sectionId,
-        equipmentIdentifier: sourceCircuit.equipmentIdentifier,
-        displayName: sourceCircuit.displayName ?? undefined,
-        sortOrder: sourceCircuit.sortOrder,
-        protectionType: sourceCircuit.protectionType ?? undefined,
-        protectionRatedCurrent: sourceCircuit.protectionRatedCurrent ?? undefined,
-        protectionCharacteristic: sourceCircuit.protectionCharacteristic ?? undefined,
-        cableType: sourceCircuit.cableType ?? undefined,
-        cableCrossSection: sourceCircuit.cableCrossSection ?? undefined,
-        cableLength: sourceCircuit.cableLength ?? undefined,
-        rcdAssignment: sourceCircuit.rcdAssignment ?? undefined,
-        terminalDesignation: sourceCircuit.terminalDesignation ?? undefined,
-        voltage: sourceCircuit.voltage ?? undefined,
-        controlRequirement: sourceCircuit.controlRequirement ?? undefined,
-        status: sourceCircuit.status ?? undefined,
-        isReserve: true,
-        remark: sourceCircuit.remark ?? undefined,
-      });
-    }
-
-    // Target circuit is no longer reserve once it receives moved rows.
-    if (Boolean(targetCircuit.isReserve)) {
-      await this.circuitRepository.update(targetCircuit.id, {
-        sectionId: targetCircuit.sectionId,
-        equipmentIdentifier: targetCircuit.equipmentIdentifier,
-        displayName: targetCircuit.displayName ?? undefined,
-        sortOrder: targetCircuit.sortOrder,
-        protectionType: targetCircuit.protectionType ?? undefined,
-        protectionRatedCurrent: targetCircuit.protectionRatedCurrent ?? undefined,
-        protectionCharacteristic: targetCircuit.protectionCharacteristic ?? undefined,
-        cableType: targetCircuit.cableType ?? undefined,
-        cableCrossSection: targetCircuit.cableCrossSection ?? undefined,
-        cableLength: targetCircuit.cableLength ?? undefined,
-        rcdAssignment: targetCircuit.rcdAssignment ?? undefined,
-        terminalDesignation: targetCircuit.terminalDesignation ?? undefined,
-        voltage: targetCircuit.voltage ?? undefined,
-        controlRequirement: targetCircuit.controlRequirement ?? undefined,
-        status: targetCircuit.status ?? undefined,
-        isReserve: false,
-        remark: targetCircuit.remark ?? undefined,
-      });
-    }
+    this.deviceRowRepository.moveRowsTransactional({
+      rows: [{ id: row.id, expectedCircuitId: row.circuitId }],
+      targetCircuitId: targetCircuit?.id,
+      createTargetCircuit,
+    });
 
     return this.deviceRowRepository.findById(rowId);
   }
@@ -436,7 +398,17 @@ export class CircuitWriteService {
       throw new Error("Invalid target circuit id.");
     }
 
-    // Bulk placeholder move creates exactly one new circuit as common target.
+    // Bulk placeholder move prepares exactly one new circuit as common target.
+    // Its actual creation happens together with the row moves in one transaction.
+    let createTargetCircuit:
+      | {
+          circuitListId: string;
+          sectionId: string;
+          equipmentIdentifier: string;
+          displayName: string;
+          sortOrder: number;
+        }
+      | undefined;
     if (!targetCircuit) {
       if (!input.targetSectionId || !input.createNewCircuit) {
         throw new Error("Invalid move target.");
@@ -446,86 +418,27 @@ export class CircuitWriteService {
       const sectionCircuits = await this.circuitRepository.listBySection(section.id);
       const nextSortOrder =
         sectionCircuits.length > 0 ? Math.max(...sectionCircuits.map((circuit) => circuit.sortOrder)) + 10 : 10;
-      const createdId = await this.circuitRepository.create({
+      createTargetCircuit = {
         circuitListId: referenceSourceCircuit.circuitListId,
         sectionId: section.id,
         equipmentIdentifier: nextIdentifier,
-        displayName: "New circuit",
+        displayName: "Neuer Stromkreis",
         sortOrder: nextSortOrder,
-        isReserve: false,
-      });
-      targetCircuit = await this.circuitRepository.findById(createdId);
-      if (!targetCircuit) {
-        throw new Error("Failed to create target circuit.");
-      }
+      };
     }
 
-    // Any source circuit emptied by bulk move is preserved as reserve circuit.
+    const targetCircuitListId = targetCircuit?.circuitListId ?? createTargetCircuit!.circuitListId;
     for (const sourceCircuit of sourceCircuits.values()) {
-      if (sourceCircuit.circuitListId !== targetCircuit.circuitListId) {
+      if (sourceCircuit.circuitListId !== targetCircuitListId) {
         throw new Error("All moved rows must belong to same circuit list as target.");
       }
     }
 
-    const targetCount = await this.deviceRowRepository.countByCircuit(targetCircuit.id);
-    let offset = 1;
-    for (const row of rows) {
-      await this.deviceRowRepository.moveToCircuit(row.id, targetCircuit.id, (targetCount + offset) * 10);
-      offset += 1;
-    }
-
-    for (const sourceCircuit of sourceCircuits.values()) {
-      const remaining = await this.deviceRowRepository.countByCircuit(sourceCircuit.id);
-      if (remaining === 0) {
-        await this.circuitRepository.update(sourceCircuit.id, {
-          sectionId: sourceCircuit.sectionId,
-          equipmentIdentifier: sourceCircuit.equipmentIdentifier,
-          displayName: sourceCircuit.displayName ?? undefined,
-          sortOrder: sourceCircuit.sortOrder,
-          protectionType: sourceCircuit.protectionType ?? undefined,
-          protectionRatedCurrent: sourceCircuit.protectionRatedCurrent ?? undefined,
-          protectionCharacteristic: sourceCircuit.protectionCharacteristic ?? undefined,
-          cableType: sourceCircuit.cableType ?? undefined,
-          cableCrossSection: sourceCircuit.cableCrossSection ?? undefined,
-          cableLength: sourceCircuit.cableLength ?? undefined,
-          rcdAssignment: sourceCircuit.rcdAssignment ?? undefined,
-          terminalDesignation: sourceCircuit.terminalDesignation ?? undefined,
-          voltage: sourceCircuit.voltage ?? undefined,
-          controlRequirement: sourceCircuit.controlRequirement ?? undefined,
-          status: sourceCircuit.status ?? undefined,
-          isReserve: true,
-          remark: sourceCircuit.remark ?? undefined,
-        });
-      }
-    }
-
-    if (Boolean(targetCircuit.isReserve)) {
-      await this.circuitRepository.update(targetCircuit.id, {
-        sectionId: targetCircuit.sectionId,
-        equipmentIdentifier: targetCircuit.equipmentIdentifier,
-        displayName: targetCircuit.displayName ?? undefined,
-        sortOrder: targetCircuit.sortOrder,
-        protectionType: targetCircuit.protectionType ?? undefined,
-        protectionRatedCurrent: targetCircuit.protectionRatedCurrent ?? undefined,
-        protectionCharacteristic: targetCircuit.protectionCharacteristic ?? undefined,
-        cableType: targetCircuit.cableType ?? undefined,
-        cableCrossSection: targetCircuit.cableCrossSection ?? undefined,
-        cableLength: targetCircuit.cableLength ?? undefined,
-        rcdAssignment: targetCircuit.rcdAssignment ?? undefined,
-        terminalDesignation: targetCircuit.terminalDesignation ?? undefined,
-        voltage: targetCircuit.voltage ?? undefined,
-        controlRequirement: targetCircuit.controlRequirement ?? undefined,
-        status: targetCircuit.status ?? undefined,
-        isReserve: false,
-        remark: targetCircuit.remark ?? undefined,
-      });
-    }
-
-    return {
-      movedRowIds: rows.map((row) => row.id),
-      targetCircuitId: targetCircuit.id,
-      createdCircuitId: input.targetCircuitId ? undefined : targetCircuit.id,
-    };
+    return this.deviceRowRepository.moveRowsTransactional({
+      rows: rows.map((row) => ({ id: row.id, expectedCircuitId: row.circuitId })),
+      targetCircuitId: targetCircuit?.id,
+      createTargetCircuit,
+    });
   }
 
   async getNextIdentifier(sectionId: string) {

tests/circuit-write.rules.test.ts

@@ -1,6 +1,7 @@
 import assert from "node:assert/strict";
 import { describe, it } from "node:test";
 import { CircuitWriteService } from "../src/domain/services/circuit-write.service.js";
+import { CircuitDeviceRowRepository } from "../src/db/repositories/circuit-device-row.repository.js";
 import { CircuitRepository } from "../src/db/repositories/circuit.repository.js";
 import { db } from "../src/db/client.js";
 import { createCircuitSchema } from "../src/shared/validation/circuit.schemas.js";
@@ -298,24 +299,24 @@ describe("circuit write service rules", () => {
   });
 
   it("moving a device row to another circuit preserves row and toggles reserve flags", async () => {
-    const updatedReserve: Array<{ id: string; isReserve: boolean }> = [];
-    const movedCalls: Array<{ rowId: string; targetCircuitId: string; sortOrder: number }> = [];
+    let transactionalMove:
+      | {
+          rows: Array<{ id: string; expectedCircuitId: string }>;
+          targetCircuitId?: string;
+          createTargetCircuit?: unknown;
+        }
+      | undefined;
     const service = new CircuitWriteService({
       deviceRowRepository: {
         async findById() {
           return { id: "r1", circuitId: "c1" } as never;
         },
-        async countByCircuit(circuitId: string) {
-          if (circuitId === "c2") {
-            return 2;
-          }
-          if (circuitId === "c1") {
-            return 0;
-          }
-          return 0;
-        },
-        async moveToCircuit(rowId: string, targetCircuitId: string, sortOrder: number) {
-          movedCalls.push({ rowId, targetCircuitId, sortOrder });
+        moveRowsTransactional(input: typeof transactionalMove) {
+          transactionalMove = input;
+          return {
+            movedRowIds: input!.rows.map((row) => row.id),
+            targetCircuitId: input!.targetCircuitId!,
+          };
         },
       } as never,
       circuitRepository: {
@@ -339,35 +340,39 @@ describe("circuit write service rules", () => {
             isReserve: 1,
           } as never;
         },
-        async update(id: string, payload: { isReserve: boolean }) {
-          updatedReserve.push({ id, isReserve: payload.isReserve });
-        },
       } as never,
     });
 
     await service.moveDeviceRow("r1", { targetCircuitId: "c2" });
-    assert.deepEqual(movedCalls, [{ rowId: "r1", targetCircuitId: "c2", sortOrder: 30 }]);
-    assert.deepEqual(updatedReserve, [
-      { id: "c1", isReserve: true },
-      { id: "c2", isReserve: false },
-    ]);
+    assert.deepEqual(transactionalMove, {
+      rows: [{ id: "r1", expectedCircuitId: "c1" }],
+      targetCircuitId: "c2",
+      createTargetCircuit: undefined,
+    });
   });
 
   it("moving a device row to placeholder creates a new circuit in target section", async () => {
-    let createdCircuitPayload: { sectionId: string; equipmentIdentifier: string; isReserve?: boolean } | null = null;
+    let preparedTarget:
+      | {
+          circuitListId: string;
+          sectionId: string;
+          equipmentIdentifier: string;
+          displayName: string;
+          sortOrder: number;
+        }
+      | undefined;
     const service = new CircuitWriteService({
       deviceRowRepository: {
         async findById() {
           return { id: "r1", circuitId: "c1" } as never;
         },
-        async countByCircuit(circuitId: string) {
-          if (circuitId === "c-new") {
-            return 0;
-          }
-          return 1;
-        },
-        async moveToCircuit() {
-          return;
+        moveRowsTransactional(input: { rows: Array<{ id: string }>; createTargetCircuit?: typeof preparedTarget }) {
+          preparedTarget = input.createTargetCircuit;
+          return {
+            movedRowIds: input.rows.map((row) => row.id),
+            targetCircuitId: "c-new",
+            createdCircuitId: "c-new",
+          };
         },
       } as never,
       circuitRepository: {
@@ -382,28 +387,11 @@ describe("circuit write service rules", () => {
               isReserve: 0,
             } as never;
           }
-          if (circuitId === "c-new") {
-            return {
-              id: "c-new",
-              sectionId: "s2",
-              circuitListId: "l1",
-              equipmentIdentifier: "-2F8",
-              sortOrder: 50,
-              isReserve: 0,
-            } as never;
-          }
           return null as never;
         },
         async listBySection() {
           return [{ sortOrder: 40 }] as never[];
         },
-        async create(payload: { sectionId: string; equipmentIdentifier: string; isReserve?: boolean }) {
-          createdCircuitPayload = payload;
-          return "c-new";
-        },
-        async update() {
-          return;
-        },
       } as never,
       circuitSectionRepository: {
         async findById() {
@@ -418,14 +406,54 @@ describe("circuit write service rules", () => {
     });
 
     await service.moveDeviceRow("r1", { targetSectionId: "s2", createNewCircuit: true });
-    assert.equal(createdCircuitPayload?.sectionId, "s2");
-    assert.equal(createdCircuitPayload?.equipmentIdentifier, "-2F8");
-    assert.equal(createdCircuitPayload?.isReserve, false);
+    assert.deepEqual(preparedTarget, {
+      circuitListId: "l1",
+      sectionId: "s2",
+      equipmentIdentifier: "-2F8",
+      displayName: "Neuer Stromkreis",
+      sortOrder: 50,
+    });
+  });
+
+  it("moving a device row to its current circuit remains a no-op", async () => {
+    let transactionalMoveCount = 0;
+    const service = new CircuitWriteService({
+      deviceRowRepository: {
+        async findById() {
+          return { id: "r1", circuitId: "c1" } as never;
+        },
+        moveRowsTransactional() {
+          transactionalMoveCount += 1;
+          throw new Error("same-circuit move must not write");
+        },
+      } as never,
+      circuitRepository: {
+        async findById() {
+          return {
+            id: "c1",
+            sectionId: "s1",
+            circuitListId: "l1",
+            equipmentIdentifier: "-1F1",
+            sortOrder: 10,
+            isReserve: 0,
+          } as never;
+        },
+      } as never,
+    });
+
+    const result = await service.moveDeviceRow("r1", { targetCircuitId: "c1" });
+    assert.equal(transactionalMoveCount, 0);
+    assert.equal(result?.id, "r1");
   });
 
   it("moving multiple device rows to a circuit preserves input order and toggles reserve", async () => {
-    const movedCalls: Array<{ rowId: string; targetCircuitId: string; sortOrder: number }> = [];
-    const reserveUpdates: Array<{ id: string; isReserve: boolean }> = [];
+    let transactionalMove:
+      | {
+          rows: Array<{ id: string; expectedCircuitId: string }>;
+          targetCircuitId?: string;
+          createTargetCircuit?: unknown;
+        }
+      | undefined;
     const service = new CircuitWriteService({
       deviceRowRepository: {
         async findById(rowId: string) {
@@ -434,14 +462,12 @@ describe("circuit write service rules", () => {
           }
           return { id: "r2", circuitId: "c2" } as never;
         },
-        async countByCircuit(circuitId: string) {
-          if (circuitId === "c3") {
-            return 1;
-          }
-          return 0;
-        },
-        async moveToCircuit(rowId: string, targetCircuitId: string, sortOrder: number) {
-          movedCalls.push({ rowId, targetCircuitId, sortOrder });
+        moveRowsTransactional(input: typeof transactionalMove) {
+          transactionalMove = input;
+          return {
+            movedRowIds: input!.rows.map((row) => row.id),
+            targetCircuitId: input!.targetCircuitId!,
+          };
         },
       } as never,
       circuitRepository: {
@@ -454,39 +480,48 @@ describe("circuit write service rules", () => {
           }
           return { id: "c3", sectionId: "s1", circuitListId: "l1", equipmentIdentifier: "-1F3", sortOrder: 30, isReserve: 1 } as never;
         },
-        async update(id: string, payload: { isReserve: boolean }) {
-          reserveUpdates.push({ id, isReserve: payload.isReserve });
-        },
       } as never,
     });
 
-    await service.moveDeviceRowsBulk({ rowIds: ["r1", "r2"], targetCircuitId: "c3" });
-    assert.deepEqual(movedCalls, [
-      { rowId: "r1", targetCircuitId: "c3", sortOrder: 20 },
-      { rowId: "r2", targetCircuitId: "c3", sortOrder: 30 },
-    ]);
-    assert.deepEqual(reserveUpdates, [
-      { id: "c1", isReserve: true },
-      { id: "c2", isReserve: true },
-      { id: "c3", isReserve: false },
-    ]);
+    const result = await service.moveDeviceRowsBulk({ rowIds: ["r1", "r2"], targetCircuitId: "c3" });
+    assert.deepEqual(transactionalMove, {
+      rows: [
+        { id: "r1", expectedCircuitId: "c1" },
+        { id: "r2", expectedCircuitId: "c2" },
+      ],
+      targetCircuitId: "c3",
+      createTargetCircuit: undefined,
+    });
+    assert.deepEqual(result, {
+      movedRowIds: ["r1", "r2"],
+      targetCircuitId: "c3",
+    });
   });
 
   it("moving multiple device rows to placeholder creates exactly one new circuit", async () => {
-    let createCount = 0;
+    let transactionCount = 0;
+    let preparedTarget:
+      | {
+          circuitListId: string;
+          sectionId: string;
+          equipmentIdentifier: string;
+          displayName: string;
+          sortOrder: number;
+        }
+      | undefined;
     const service = new CircuitWriteService({
       deviceRowRepository: {
         async findById(rowId: string) {
           return { id: rowId, circuitId: rowId === "r1" ? "c1" : "c2" } as never;
         },
-        async countByCircuit(circuitId: string) {
-          if (circuitId === "c-new") {
-            return 0;
-          }
-          return 1;
-        },
-        async moveToCircuit() {
-          return;
+        moveRowsTransactional(input: { rows: Array<{ id: string }>; createTargetCircuit?: typeof preparedTarget }) {
+          transactionCount += 1;
+          preparedTarget = input.createTargetCircuit;
+          return {
+            movedRowIds: input.rows.map((row) => row.id),
+            targetCircuitId: "c-new",
+            createdCircuitId: "c-new",
+          };
         },
       } as never,
       circuitRepository: {
@@ -494,21 +529,11 @@ describe("circuit write service rules", () => {
           if (circuitId === "c1" || circuitId === "c2") {
             return { id: circuitId, sectionId: "s1", circuitListId: "l1", equipmentIdentifier: "-1F1", sortOrder: 10, isReserve: 0 } as never;
           }
-          if (circuitId === "c-new") {
-            return { id: "c-new", sectionId: "s2", circuitListId: "l1", equipmentIdentifier: "-2F8", sortOrder: 40, isReserve: 0 } as never;
-          }
           return null as never;
         },
         async listBySection() {
           return [{ sortOrder: 30 }] as never[];
         },
-        async create() {
-          createCount += 1;
-          return "c-new";
-        },
-        async update() {
-          return;
-        },
       } as never,
       circuitSectionRepository: {
         async findById() {
@@ -527,7 +552,14 @@ describe("circuit write service rules", () => {
       targetSectionId: "s2",
       createNewCircuit: true,
     });
-    assert.equal(createCount, 1);
+    assert.equal(transactionCount, 1);
+    assert.deepEqual(preparedTarget, {
+      circuitListId: "l1",
+      sectionId: "s2",
+      equipmentIdentifier: "-2F8",
+      displayName: "Neuer Stromkreis",
+      sortOrder: 40,
+    });
     assert.equal(result.createdCircuitId, "c-new");
   });
 
@@ -650,6 +682,94 @@ describe("circuit write service rules", () => {
     }
   });
 
+  it("bulk device row move uses one synchronous transaction callback", () => {
+    const repository = new CircuitDeviceRowRepository();
+    const originalTransaction = (db as unknown as { transaction: unknown }).transaction;
+
+    let callbackReturnedPromise = false;
+    let selectCall = 0;
+    let rowUpdateCount = 0;
+    const selectedRows = [
+      [
+        { id: "r1", circuitId: "c1" },
+        { id: "r2", circuitId: "c2" },
+      ],
+      [{ id: "c3", circuitListId: "l1" }],
+      [
+        { id: "c1", circuitListId: "l1" },
+        { id: "c2", circuitListId: "l1" },
+      ],
+      [{ id: "existing-target-row", sortOrder: 10 }],
+      [],
+      [],
+    ];
+
+    (db as unknown as { transaction: (cb: (tx: unknown) => unknown) => void }).transaction = (cb) => {
+      const fakeTx = {
+        select() {
+          const rows = selectedRows[selectCall++] ?? [];
+          const query = {
+            from() {
+              return query;
+            },
+            where() {
+              return query;
+            },
+            limit() {
+              return query;
+            },
+            all() {
+              return rows;
+            },
+          };
+          return query;
+        },
+        update() {
+          return {
+            set() {
+              return {
+                where() {
+                  return {
+                    run() {
+                      rowUpdateCount += 1;
+                      return { changes: 1 };
+                    },
+                  };
+                },
+              };
+            },
+          };
+        },
+      };
+      const callbackResult = cb(fakeTx);
+      callbackReturnedPromise = Boolean(
+        callbackResult && typeof (callbackResult as Promise<unknown>).then === "function"
+      );
+      if (callbackReturnedPromise) {
+        throw new Error("Transaction function cannot return a promise");
+      }
+    };
+
+    try {
+      const result = repository.moveRowsTransactional({
+        rows: [
+          { id: "r1", expectedCircuitId: "c1" },
+          { id: "r2", expectedCircuitId: "c2" },
+        ],
+        targetCircuitId: "c3",
+      });
+      assert.equal(callbackReturnedPromise, false);
+      assert.equal(rowUpdateCount, 5);
+      assert.deepEqual(result, {
+        movedRowIds: ["r1", "r2"],
+        targetCircuitId: "c3",
+        createdCircuitId: undefined,
+      });
+    } finally {
+      (db as unknown as { transaction: unknown }).transaction = originalTransaction;
+    }
+  });
+
   it("tracks local edits on linked device rows as overridden fields", async () => {
     let savedOverrides: string | undefined;
     const current = {