fix custom widget review findings

apps/nextjs/src/app/[locale]/manage/custom-widgets/_custom-widget-form.tsx

@@ -145,6 +145,7 @@ export function CustomWidgetForm({ mode, initialValues, definitionId }: CustomWi
             key={id}
             component="a"
             href={`#${id}`}
+            onClick={() => setMobilePane(id === "preview" ? "preview" : "configure")}
             size="compact-sm"
             variant="subtle"
             color={invalidSections.has(id) ? "red" : undefined}

apps/nextjs/src/app/[locale]/manage/custom-widgets/_custom-widget-preview-panel.spec.tsx

@@ -22,6 +22,7 @@ vi.mock("@homarr/api/client", () => ({
 vi.mock("@homarr/translation/client", () => ({ useScopedI18n: () => (key: string) => key }));
 vi.mock("@homarr/notifications", () => ({ showErrorNotification: vi.fn() }));
 const rendererAttempt = vi.hoisted(() => vi.fn());
+const codeEditorProps = vi.hoisted(() => vi.fn());
 
 vi.mock("@homarr/widgets/custom-api/custom-jsx-display", () => ({
   default: ({ data }: { data: Record<string, unknown> }) => {
@@ -32,7 +33,12 @@ vi.mock("@homarr/widgets/custom-api/custom-jsx-display", () => ({
     return <div>widget-renderer</div>;
   },
 }));
-vi.mock("./_code-editor", () => ({ CodeEditor: ({ label }: { label: string }) => <div>{label}</div> }));
+vi.mock("./_code-editor", () => ({
+  CodeEditor: (props: { label: string; readOnly?: boolean }) => {
+    codeEditorProps(props);
+    return <div>{props.label}</div>;
+  },
+}));
 vi.mock("./_custom-widget-preview-action", () => ({ PreviewActionControl: () => <div>action-control</div> }));
 
 let root: Root;
@@ -109,6 +115,7 @@ describe("Custom Widget preview panel", () => {
     );
     await act(async () => dataTab?.click());
     expect(host.textContent).toContain("requestData");
+    expect(codeEditorProps).toHaveBeenCalledWith(expect.objectContaining({ label: "requestData", readOnly: true }));
     expect(host.textContent).not.toContain("invalid");
 
     const optionsTab = [...host.querySelectorAll<HTMLElement>('[role="tab"]')].find((element) =>

apps/nextjs/src/app/[locale]/manage/custom-widgets/_custom-widget-preview-panel.tsx

@@ -172,6 +172,7 @@ export function CustomWidgetPreviewPanel(props: PreviewPanelProps) {
               label={t("requestData")}
               language="json"
               value={JSON.stringify({ data: props.preview.data, status: props.preview.status }, null, 2)}
+              readOnly
               onChange={() => undefined}
             />
           </Tabs.Panel>
@@ -251,6 +252,7 @@ export function CustomWidgetPreviewPanel(props: PreviewPanelProps) {
                   label={t("journal")}
                   language="json"
                   value={JSON.stringify(journalQuery.data ?? [], null, 2)}
+                  readOnly
                   onChange={() => undefined}
                 />
               )}

apps/nextjs/src/app/[locale]/manage/custom-widgets/_custom-widget-sources-editor.tsx

@@ -87,7 +87,9 @@ export function CustomWidgetSourcesEditor({
     form.setFieldValue("secrets", [...current, { sourceId, kind, value, hasValue: existing?.hasValue }]);
   };
   const addSource = () => {
-    const id = sources.length === 0 ? "default" : `source-${sources.length + 1}`;
+    let suffix = sources.length + 1;
+    while (sources.some(({ id }) => id === `source-${suffix}`)) suffix += 1;
+    const id = sources.length === 0 ? "default" : `source-${suffix}`;
     form.setFieldValue(
       "sources",
       JSON.stringify(

apps/nextjs/src/app/[locale]/manage/custom-widgets/_json-preview-editor.spec.tsx

@@ -0,0 +1,46 @@
+// @vitest-environment jsdom
+
+import { act } from "react";
+import { createRoot } from "react-dom/client";
+import type { Root } from "react-dom/client";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+import { JsonPreviewEditor } from "./_json-preview-editor";
+
+const editorProps = vi.hoisted(() => vi.fn());
+
+vi.mock("@homarr/translation/client", () => ({ useScopedI18n: () => (key: string) => key }));
+vi.mock("./_code-editor", () => ({
+  CodeEditor: (props: { error?: string; onChange(value: string): void }) => {
+    editorProps(props);
+    return <button onClick={() => props.onChange("{invalid")}>edit</button>;
+  },
+}));
+
+let root: Root;
+let host: HTMLDivElement;
+
+beforeEach(() => {
+  (globalThis as { IS_REACT_ACT_ENVIRONMENT?: boolean }).IS_REACT_ACT_ENVIRONMENT = true;
+  host = document.createElement("div");
+  document.body.append(host);
+  root = createRoot(host);
+});
+
+afterEach(async () => {
+  await act(() => root.unmount());
+  host.remove();
+});
+
+describe("preview JSON editor", () => {
+  it("surfaces invalid JSON and clears the previously rendered options", async () => {
+    const onChange = vi.fn();
+    await act(async () => {
+      root.render(<JsonPreviewEditor id="options" label="Options" value={{ stale: true }} onChange={onChange} />);
+    });
+    await act(async () => (host.querySelector("button") as HTMLButtonElement).click());
+
+    expect(onChange).toHaveBeenCalledWith({});
+    expect(editorProps).toHaveBeenLastCalledWith(expect.objectContaining({ error: "invalidJson" }));
+  });
+});

apps/nextjs/src/app/[locale]/manage/custom-widgets/_json-preview-editor.tsx

@@ -2,6 +2,8 @@
 
 import { useEffect, useState } from "react";
 
+import { useScopedI18n } from "@homarr/translation/client";
+
 import { CodeEditor } from "./_code-editor";
 import { isRecord, parseJson } from "./_custom-widget-form-utils";
 
@@ -16,19 +18,26 @@ export function JsonPreviewEditor({
   value: Record<string, unknown>;
   onChange(value: Record<string, unknown>): void;
 }) {
+  const t = useScopedI18n("customWidget.workbench.builder");
   const serialized = JSON.stringify(value, null, 2);
   const [draft, setDraft] = useState(serialized);
-  useEffect(() => setDraft(serialized), [serialized]);
+  const [invalid, setInvalid] = useState(false);
+  useEffect(() => {
+    if (!invalid) setDraft(serialized);
+  }, [invalid, serialized]);
   return (
     <CodeEditor
       id={id}
       label={label}
       language="json"
       value={draft}
+      error={invalid ? t("invalidJson") : undefined}
       onChange={(next) => {
         setDraft(next);
         const parsed = parseJson(next);
-        if (isRecord(parsed)) onChange(parsed);
+        const valid = isRecord(parsed);
+        setInvalid(!valid);
+        onChange(valid ? parsed : {});
       }}
     />
   );

apps/nextjs/src/app/[locale]/manage/custom-widgets/_unsaved-changes-guard.spec.ts

@@ -48,4 +48,17 @@ describe("custom widget unsaved changes guard", () => {
     expect(listLink.dispatchEvent(new MouseEvent("click", { bubbles: true, cancelable: true, button: 0 }))).toBe(true);
     expect(confirmNavigation).not.toHaveBeenCalled();
   });
+
+  it("restores the current page and confirms browser history navigation", () => {
+    window.history.replaceState(null, "", "/en/manage/custom-widgets");
+    window.history.pushState(null, "", "/en/manage/custom-widgets/edit/widget-1");
+    const confirmNavigation = vi.fn();
+    cleanups.push(registerUnsavedChangesGuard({ isDirty: () => true, confirmNavigation }));
+
+    window.history.replaceState(null, "", "/en/manage/custom-widgets");
+    window.dispatchEvent(new PopStateEvent("popstate"));
+
+    expect(window.location.pathname).toBe("/en/manage/custom-widgets/edit/widget-1");
+    expect(confirmNavigation).toHaveBeenCalledWith("/en/manage/custom-widgets");
+  });
 });

apps/nextjs/src/app/[locale]/manage/custom-widgets/_unsaved-changes-guard.ts

@@ -4,6 +4,7 @@ interface UnsavedChangesGuardOptions {
 }
 
 export function registerUnsavedChangesGuard({ isDirty, confirmNavigation }: UnsavedChangesGuardOptions) {
+  let currentHref = `${window.location.pathname}${window.location.search}${window.location.hash}`;
   const handleClick = (event: MouseEvent) => {
     if (!isDirty() || event.defaultPrevented || event.button !== 0) return;
     if (event.metaKey || event.ctrlKey || event.shiftKey || event.altKey) return;
@@ -32,11 +33,22 @@ export function registerUnsavedChangesGuard({ isDirty, confirmNavigation }: Unsa
     event.preventDefault();
     event.returnValue = true;
   };
+  const handlePopState = () => {
+    const destination = `${window.location.pathname}${window.location.search}${window.location.hash}`;
+    if (!isDirty()) {
+      currentHref = destination;
+      return;
+    }
+    window.history.pushState(window.history.state, "", currentHref);
+    confirmNavigation(destination);
+  };
 
   document.addEventListener("click", handleClick, true);
   window.addEventListener("beforeunload", handleBeforeUnload);
+  window.addEventListener("popstate", handlePopState);
   return () => {
     document.removeEventListener("click", handleClick, true);
     window.removeEventListener("beforeunload", handleBeforeUnload);
+    window.removeEventListener("popstate", handlePopState);
   };
 }