Add project transfer controls

src/app/projects/[projectId]/page.tsx

@@ -12,6 +12,7 @@ import {
   createRoom,
   deleteProjectDevice,
   disconnectProjectDeviceRows,
+  exportProjectTransfer,
   getProjectDeviceSyncPreview,
   listCircuitLists,
   listDistributionBoards,
@@ -20,6 +21,7 @@ import {
   listProjectDevices,
   listProjects,
   listRooms,
+  importProjectTransfer,
   synchronizeProjectDeviceRows,
   updateProjectDevice,
   updateProjectSettings,
@@ -349,6 +351,67 @@ export default function ProjectDetailPage() {
     }
   }
 
+  async function handleExportProject() {
+    if (!project) {
+      return;
+    }
+    setIsSaving(true);
+    setError(null);
+    try {
+      const transfer = await exportProjectTransfer(project.id);
+      const blob = new Blob([JSON.stringify(transfer, null, 2)], {
+        type: "application/json",
+      });
+      const url = URL.createObjectURL(blob);
+      const anchor = document.createElement("a");
+      anchor.href = url;
+      anchor.download = `${project.name.replace(/[^a-zA-Z0-9_-]+/g, "-") || "projekt"}.leistungsbilanz.json`;
+      anchor.click();
+      URL.revokeObjectURL(url);
+    } catch (err) {
+      setError(
+        err instanceof Error
+          ? err.message
+          : "Projekt konnte nicht exportiert werden."
+      );
+    } finally {
+      setIsSaving(false);
+    }
+  }
+
+  async function handleImportProject(
+    transfer: unknown,
+    mode: "replace" | "duplicate"
+  ) {
+    if (!project) {
+      return;
+    }
+    setIsSaving(true);
+    setError(null);
+    try {
+      const result = await importProjectTransfer(
+        project.id,
+        mode,
+        project.currentRevision,
+        transfer
+      );
+      if (mode === "duplicate" && "projectId" in result) {
+        window.location.href = `/projects/${result.projectId}`;
+        return;
+      }
+      window.location.reload();
+    } catch (err) {
+      setError(
+        err instanceof Error
+          ? err.message
+          : "Projektdatei konnte nicht importiert werden."
+      );
+      setIsProjectSettingsOpen(false);
+    } finally {
+      setIsSaving(false);
+    }
+  }
+
   async function openProjectDeviceSyncPreview(projectDeviceId: string) {
     if (!projectId) {
       return;
@@ -1015,6 +1078,8 @@ export default function ProjectDetailPage() {
         <ProjectSettingsModal
           isSaving={isSaving}
           onClose={() => setIsProjectSettingsOpen(false)}
+          onExport={handleExportProject}
+          onImport={handleImportProject}
           onSave={handleSaveProjectSettings}
           project={project}
         />

src/db/repositories/project-state-restore-command.repository.ts

@@ -6,7 +6,6 @@ import {
 } from "../../domain/models/project-state-restore-command.model.js";
 import {
   parseProjectStateSnapshot,
-  serializeProjectStateSnapshot,
   type ProjectStateSnapshot,
 } from "../../domain/models/project-state-snapshot.model.js";
 import type {
@@ -24,11 +23,11 @@ import { floors } from "../schema/floors.js";
 import { legacyConsumerCircuitMigrations } from "../schema/legacy-consumer-circuit-migrations.js";
 import { legacyConsumerMigrationReports } from "../schema/legacy-consumer-migration-report.js";
 import { projectDevices } from "../schema/project-devices.js";
+import { projectChangeSets } from "../schema/project-change-sets.js";
 import { projects } from "../schema/projects.js";
 import { rooms } from "../schema/rooms.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
 import {
-  hashProjectStatePayload,
   readProjectStateSnapshot,
 } from "./project-state-snapshot.persistence.js";
 
@@ -63,7 +62,8 @@ export class ProjectStateRestoreCommandRepository
     }
     if (
       current.payloadSha256 !==
-      input.command.payload.expectedStateSha256
+        input.command.payload.expectedStateSha256 &&
+      !matchesHistoryRestoreTarget(tx, input, current.state)
     ) {
       throw new ProjectStateConflictError(
         input.projectId,
@@ -75,18 +75,90 @@ export class ProjectStateRestoreCommandRepository
     const targetState = parseProjectStateSnapshot(
       input.command.payload.targetState
     );
-    const targetPayloadJson = serializeProjectStateSnapshot(targetState);
+    replaceProjectState(tx, targetState);
+    const persistedTarget = readProjectStateSnapshot(tx, input.projectId);
+    if (!persistedTarget) {
+      throw new Error("Restored project could not be loaded.");
+    }
     const inverse = createProjectStateRestoreCommand(
-      hashProjectStatePayload(targetPayloadJson),
+      persistedTarget.payloadSha256,
       current.state
     );
 
-    replaceProjectState(tx, targetState);
-
     return inverse;
   }
 }
 
+function matchesHistoryRestoreTarget(
+  database: AppDatabase,
+  input: ExecuteProjectStateRestoreCommandInput,
+  currentState: ProjectStateSnapshot
+) {
+  if (
+    (input.source !== "undo" && input.source !== "redo") ||
+    !input.historyTargetChangeSetId
+  ) {
+    return false;
+  }
+  const changeSet = database
+    .select({
+      forwardPayloadJson: projectChangeSets.forwardPayloadJson,
+      inversePayloadJson: projectChangeSets.inversePayloadJson,
+    })
+    .from(projectChangeSets)
+    .where(eq(projectChangeSets.id, input.historyTargetChangeSetId))
+    .get();
+  if (!changeSet) {
+    return false;
+  }
+  try {
+    const serialized =
+      input.source === "undo"
+        ? changeSet.forwardPayloadJson
+        : changeSet.inversePayloadJson;
+    const command = JSON.parse(serialized) as {
+      type?: unknown;
+      payload?: { targetState?: unknown };
+    };
+    if (command.type !== "project.restore-state") {
+      return false;
+    }
+    const expectedState = parseProjectStateSnapshot(
+      command.payload?.targetState
+    );
+    return (
+      canonicalProjectState(expectedState) ===
+      canonicalProjectState(currentState)
+    );
+  } catch {
+    return false;
+  }
+}
+
+function canonicalProjectState(state: ProjectStateSnapshot) {
+  return JSON.stringify({
+    ...state,
+    distributionBoards: byId(state.distributionBoards),
+    circuitLists: byId(state.circuitLists),
+    circuitSections: byId(state.circuitSections),
+    circuits: byId(
+      state.circuits.map((circuit) => ({
+        ...circuit,
+        deviceRows: byId(circuit.deviceRows),
+      }))
+    ),
+    projectDevices: byId(state.projectDevices),
+    floors: byId(state.floors),
+    rooms: byId(state.rooms),
+  });
+}
+
+function byId<T extends { id: string }>(entries: readonly T[]) {
+  return [...entries].sort((left, right) =>
+    left.id.localeCompare(right.id)
+  );
+}
+
 function replaceProjectState(
   database: AppDatabase,
   state: ProjectStateSnapshot

src/frontend/components/project-settings-modal.tsx

@@ -16,6 +16,11 @@ export interface ProjectSettingsInput {
 interface ProjectSettingsModalProps {
   isSaving: boolean;
   onClose: () => void;
+  onExport: () => Promise<void>;
+  onImport: (
+    transfer: unknown,
+    mode: "replace" | "duplicate"
+  ) => Promise<void>;
   onSave: (input: ProjectSettingsInput) => Promise<void>;
   project: ProjectDto;
 }
@@ -23,6 +28,8 @@ interface ProjectSettingsModalProps {
 export function ProjectSettingsModal({
   isSaving,
   onClose,
+  onExport,
+  onImport,
   onSave,
   project,
 }: ProjectSettingsModalProps) {
@@ -45,6 +52,13 @@ export function ProjectSettingsModal({
   const [threePhaseVoltageV, setThreePhaseVoltageV] = useState(
     String(project.threePhaseVoltageV)
   );
+  const [transfer, setTransfer] = useState<unknown>(null);
+  const [transferFilename, setTransferFilename] = useState("");
+  const [importMode, setImportMode] = useState<"replace" | "duplicate">(
+    "duplicate"
+  );
+  const [replaceConfirmed, setReplaceConfirmed] = useState(false);
+  const [fileError, setFileError] = useState<string | null>(null);
 
   async function handleSubmit(event: FormEvent<HTMLFormElement>) {
     event.preventDefault();
@@ -64,6 +78,21 @@ export function ProjectSettingsModal({
     Number(singlePhaseVoltageV) > 0 &&
     Number(threePhaseVoltageV) > 0;
 
+  async function handleTransferFile(file: File | undefined) {
+    setTransfer(null);
+    setTransferFilename("");
+    setFileError(null);
+    if (!file) {
+      return;
+    }
+    try {
+      setTransfer(JSON.parse(await file.text()) as unknown);
+      setTransferFilename(file.name);
+    } catch {
+      setFileError("Die ausgewählte Datei enthält kein gültiges JSON.");
+    }
+  }
+
   return (
     <>
       <div
@@ -193,6 +222,99 @@ export function ProjectSettingsModal({
                     value={threePhaseVoltageV}
                   />
                 </div>
+                <div className="col-12">
+                  <hr className="my-2" />
+                  <h3 className="h6">Projekt importieren oder exportieren</h3>
+                  <p className="text-secondary small">
+                    Der Export enthält den vollständigen unterstützten
+                    Projektzustand. Beim Duplizieren bleibt dieses Projekt
+                    unverändert.
+                  </p>
+                  <button
+                    className="btn btn-outline-primary mb-3"
+                    disabled={isSaving}
+                    onClick={() => void onExport()}
+                    type="button"
+                  >
+                    Projektdatei herunterladen
+                  </button>
+                  <label className="form-label d-block" htmlFor="project-import">
+                    Projektdatei auswählen
+                  </label>
+                  <input
+                    accept=".json,application/json"
+                    className="form-control"
+                    id="project-import"
+                    onChange={(event) =>
+                      void handleTransferFile(event.target.files?.[0])
+                    }
+                    type="file"
+                  />
+                  {transferFilename ? (
+                    <div className="form-text">{transferFilename} ist bereit.</div>
+                  ) : null}
+                  {fileError ? (
+                    <div className="text-danger small mt-1">{fileError}</div>
+                  ) : null}
+                  <div className="d-flex flex-wrap gap-3 mt-3">
+                    <label className="form-check">
+                      <input
+                        checked={importMode === "duplicate"}
+                        className="form-check-input"
+                        name="import-mode"
+                        onChange={() => setImportMode("duplicate")}
+                        type="radio"
+                      />
+                      <span className="form-check-label">
+                        Als neues Projekt duplizieren
+                      </span>
+                    </label>
+                    <label className="form-check">
+                      <input
+                        checked={importMode === "replace"}
+                        className="form-check-input"
+                        name="import-mode"
+                        onChange={() => setImportMode("replace")}
+                        type="radio"
+                      />
+                      <span className="form-check-label">
+                        Dieses Projekt ersetzen
+                      </span>
+                    </label>
+                  </div>
+                  {importMode === "replace" ? (
+                    <label className="form-check mt-2">
+                      <input
+                        checked={replaceConfirmed}
+                        className="form-check-input"
+                        onChange={(event) =>
+                          setReplaceConfirmed(event.target.checked)
+                        }
+                        type="checkbox"
+                      />
+                      <span className="form-check-label text-danger">
+                        Ich bestätige, dass der aktuelle Projektstand ersetzt
+                        wird.
+                      </span>
+                    </label>
+                  ) : null}
+                  <button
+                    className="btn btn-outline-danger mt-3"
+                    disabled={
+                      isSaving ||
+                      transfer === null ||
+                      (importMode === "replace" && !replaceConfirmed)
+                    }
+                    onClick={() =>
+                      transfer === null
+                        ? undefined
+                        : void onImport(transfer, importMode)
+                    }
+                    type="button"
+                  >
+                    Projektdatei importieren
+                  </button>
+                </div>
               </div>
             </div>
             <div className="modal-footer">

src/frontend/utils/api.ts

@@ -229,6 +229,29 @@ export function updateProjectSettings(
   );
 }
 
+export function exportProjectTransfer(projectId: string) {
+  return request<unknown>(`/api/projects/${projectId}/export`);
+}
+
+export function importProjectTransfer(
+  projectId: string,
+  mode: "replace" | "duplicate",
+  expectedRevision: number,
+  transfer: unknown
+) {
+  return request<
+    | { projectId: string; name: string }
+    | ProjectSettingsCommandResultDto
+  >(`/api/projects/${projectId}/import`, {
+    method: "POST",
+    body: JSON.stringify(
+      mode === "replace"
+        ? { mode, expectedRevision, transfer }
+        : { mode, transfer }
+    ),
+  });
+}
+
 export function listDistributionBoards(projectId: string) {
   return request<DistributionBoardDto[]>(`/api/projects/${projectId}/distribution-boards`);
 }

tests/project-state-restore-command.repository.test.ts

@@ -22,9 +22,9 @@ import { ProjectDeviceStructureProjectCommandRepository } from "../src/db/reposi
 import { ProjectHistoryRepository } from "../src/db/repositories/project-history.repository.js";
 import { ProjectLocationStructureProjectCommandRepository } from "../src/db/repositories/project-location-structure-project-command.repository.js";
 import { ProjectSnapshotRepository } from "../src/db/repositories/project-snapshot.repository.js";
+import { ProjectTransferRepository } from "../src/db/repositories/project-transfer.repository.js";
 import { ProjectStateRestoreCommandRepository } from "../src/db/repositories/project-state-restore-command.repository.js";
 import { ProjectSettingsProjectCommandRepository } from "../src/db/repositories/project-settings-project-command.repository.js";
-import { readProjectStateSnapshot } from "../src/db/repositories/project-state-snapshot.persistence.js";
 import { circuitDeviceRows } from "../src/db/schema/circuit-device-rows.js";
 import { circuitLists } from "../src/db/schema/circuit-lists.js";
 import { circuitSections } from "../src/db/schema/circuit-sections.js";
@@ -37,6 +37,12 @@ import { projectDevices } from "../src/db/schema/project-devices.js";
 import { projectRevisions } from "../src/db/schema/project-revisions.js";
 import { projectSnapshots } from "../src/db/schema/project-snapshots.js";
 import { projects } from "../src/db/schema/projects.js";
+import { projectChangeSets } from "../src/db/schema/project-change-sets.js";
+import {
+  hashProjectStatePayload,
+  readProjectStateSnapshot,
+} from "../src/db/repositories/project-state-snapshot.persistence.js";
+import { serializeProjectStateSnapshot } from "../src/domain/models/project-state-snapshot.model.js";
 import { rooms } from "../src/db/schema/rooms.js";
 import { ProjectStateConflictError } from "../src/domain/errors/project-state-conflict.error.js";
 import { ProjectCommandService } from "../src/domain/services/project-command.service.js";
@@ -253,6 +259,63 @@ function seedUpgradeOnlyData(context: DatabaseContext) {
 }
 
 describe("project state restore command", () => {
+  it("undoes a remapped cross-project import using the persisted target hash", () => {
+    const context = createTestDatabase();
+    try {
+      const transfers = new ProjectTransferRepository(context.db);
+      const transfer = transfers.exportProject("project-1");
+      assert.ok(transfer);
+      const duplicate = transfers.importDuplicate(transfer);
+      const before = readProjectStateSnapshot(
+        context.db,
+        duplicate.projectId
+      );
+      assert.ok(before);
+      const prepared = transfers.prepareReplace(
+        duplicate.projectId,
+        transfer
+      );
+      assert.ok(prepared);
+      const service = createService(context);
+      const restored = service.executeRestore({
+        projectId: duplicate.projectId,
+        expectedRevision: 0,
+        description: "Projektimport wiederherstellen",
+        command: prepared.command,
+      });
+      const legacyExpectedHash = hashProjectStatePayload(
+        serializeProjectStateSnapshot(
+          prepared.command.payload.targetState
+        )
+      );
+      const storedChangeSet = context.db
+        .select()
+        .from(projectChangeSets)
+        .where(eq(projectChangeSets.id, restored.revision.changeSetId))
+        .get();
+      assert.ok(storedChangeSet);
+      const inverse = JSON.parse(storedChangeSet.inversePayloadJson);
+      inverse.payload.expectedStateSha256 = legacyExpectedHash;
+      context.db
+        .update(projectChangeSets)
+        .set({ inversePayloadJson: JSON.stringify(inverse) })
+        .where(eq(projectChangeSets.id, storedChangeSet.id))
+        .run();
+      const undone = service.undo({
+        projectId: duplicate.projectId,
+        expectedRevision: 1,
+      });
+      assert.equal(undone.revision.revisionNumber, 2);
+      assert.equal(
+        readProjectStateSnapshot(context.db, duplicate.projectId)
+          ?.payloadSha256,
+        before.payloadSha256
+      );
+    } finally {
+      context.close();
+    }
+  });
+
   it("restores a complete snapshot as a revision and supports undo and redo", () => {
     const context = createTestDatabase();
     try {