Merge pull request #7 from sean351/feat/running-apps-dropdown

feat: show running PulseAudio apps in dropdown for easier knob targeting

src/turnup/ui/server.py

@@ -114,6 +114,30 @@ async def save_config(request: Request) -> dict[str, bool]:
     return {"ok": True}
 
 
+# ── Running apps API ──────────────────────────────────────────────────────────
+
+@app.get("/api/apps")
+def list_running_apps() -> list[str]:
+    """Return unique app names from currently active PulseAudio/PipeWire sink inputs.
+
+    Returns both ``application.name`` and ``application.process.binary`` values
+    (deduplicated) because the daemon's matching logic accepts either.  Falls
+    back to an empty list if pulsectl is unavailable or no server is reachable.
+    """
+    try:
+        import pulsectl  # optional — only present when [ui] extra is installed
+        with pulsectl.Pulse("turnup-ui-apps") as pulse:
+            seen: set[str] = set()
+            for si in pulse.sink_input_list():
+                for field in ("application.name", "application.process.binary"):
+                    val = (si.proplist.get(field) or "").strip()
+                    if val:
+                        seen.add(val)
+            return sorted(seen, key=str.lower)
+    except Exception:
+        return []
+
+
 # ── Presets API ────────────────────────────────────────────────────────────────
 
 def _preset_path(name: str) -> Path:

ui/package.json

@@ -7,7 +7,9 @@
     "dev": "vite",
     "build": "tsc -b && vite build",
     "lint": "eslint .",
-    "preview": "vite preview"
+    "preview": "vite preview",
+    "test": "vitest run",
+    "test:watch": "vitest"
   },
   "dependencies": {
     "react": "^19.2.0",
@@ -15,16 +17,22 @@
   },
   "devDependencies": {
     "@eslint/js": "^9.39.1",
+    "@testing-library/jest-dom": "^6.9.1",
+    "@testing-library/react": "^16.3.2",
+    "@testing-library/user-event": "^14.6.1",
     "@types/node": "^24.10.1",
     "@types/react": "^19.2.7",
     "@types/react-dom": "^19.2.3",
     "@vitejs/plugin-react": "^5.1.1",
+    "@vitest/coverage-v8": "^4.0.18",
     "eslint": "^9.39.1",
     "eslint-plugin-react-hooks": "^7.0.1",
     "eslint-plugin-react-refresh": "^0.4.24",
     "globals": "^16.5.0",
+    "jsdom": "^28.1.0",
     "typescript": "~5.9.3",
     "typescript-eslint": "^8.48.0",
-    "vite": "^7.3.1"
+    "vite": "^7.3.1",
+    "vitest": "^4.0.18"
   }
 }

ui/src/App.tsx

@@ -14,12 +14,14 @@ const BTN_INDICES  = ['0', '1', '2', '3', '4'] as const;
 let toastSeq = 0;
 
 export default function App() {
-  const [config,  setConfig]  = useState<Config | null>(null);
-  const [saved,   setSaved]   = useState<Config | null>(null);
-  const [presets, setPresets] = useState<string[]>([]);
-  const [toasts,  setToasts]  = useState<ToastItem[]>([]);
-  const [loading, setLoading] = useState(true);
-  const [saving,  setSaving]  = useState(false);
+  const [config,      setConfig]      = useState<Config | null>(null);
+  const [saved,       setSaved]       = useState<Config | null>(null);
+  const [presets,     setPresets]     = useState<string[]>([]);
+  const [toasts,      setToasts]      = useState<ToastItem[]>([]);
+  const [loading,     setLoading]     = useState(true);
+  const [saving,      setSaving]      = useState(false);
+  const [runningApps, setRunningApps] = useState<string[]>([]);
+  const [appsLoading, setAppsLoading] = useState(false);
 
   const addToast = useCallback((message: string, type: ToastItem['type'] = 'success') => {
     const id = ++toastSeq;
@@ -39,6 +41,15 @@ export default function App() {
     }
   }, []);
 
+  const loadApps = useCallback(async () => {
+    setAppsLoading(true);
+    try {
+      setRunningApps(await api.fetchRunningApps());
+    } finally {
+      setAppsLoading(false);
+    }
+  }, []);
+
   // Initial load
   useEffect(() => {
     void (async () => {
@@ -52,8 +63,9 @@ export default function App() {
         setLoading(false);
       }
       await loadPresets();
+      await loadApps();
     })();
-  }, [addToast, loadPresets]);
+  }, [addToast, loadPresets, loadApps]);
 
   const isDirty = config !== null && JSON.stringify(config) !== JSON.stringify(saved);
 
@@ -128,13 +140,24 @@ export default function App() {
         />
 
         <section className="card" id="knobs">
-          <h2>Knobs</h2>
+          <h2>
+            Knobs
+            <button
+              className="btn-secondary btn-refresh-apps"
+              onClick={() => void loadApps()}
+              disabled={appsLoading}
+              title="Refresh list of running apps"
+            >
+              {appsLoading ? '…' : '↻'} Running apps
+            </button>
+          </h2>
           <div className="cards-grid">
             {KNOB_INDICES.map((i) => (
               <KnobCard
                 key={i}
                 index={Number(i)}
                 knob={config.knobs[i] ?? { action: 'sink_volume', target: 'default' }}
+                runningApps={runningApps}
                 onChange={(knob) =>
                   patchConfig('knobs', { ...config.knobs, [i]: knob })
                 }

ui/src/__tests__/KnobCard.test.tsx

@@ -0,0 +1,173 @@
+/**
+ * Tests for KnobCard — running-apps dropdown feature.
+ *
+ * Covers:
+ *  app_volume  — datalist rendered when runningApps provided
+ *  app_volume  — no datalist when runningApps is empty / not passed
+ *  app_volume  — picking a suggestion calls onChange with the chosen value
+ *  group_volume — app-picker select rendered when runningApps provided
+ *  group_volume — no app-picker when runningApps is empty / not passed
+ *  group_volume — Add button is disabled until an app is selected
+ *  group_volume — clicking Add appends the app to targets
+ *  group_volume — clicking Add does NOT add a duplicate app
+ */
+
+import { render, screen, fireEvent } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
+import { KnobCard } from '../components/KnobCard';
+import type { KnobConfig } from '../types';
+
+// ── helpers ───────────────────────────────────────────────────────────────────
+
+function renderCard(
+  overrides: Partial<KnobConfig> = {},
+  runningApps?: string[],
+  onChange = vi.fn(),
+) {
+  const knob: KnobConfig = {
+    action: 'app_volume',
+    target: 'default',
+    ...overrides,
+  };
+  return {
+    onChange,
+    ...render(
+      <KnobCard index={1} knob={knob} runningApps={runningApps} onChange={onChange} />,
+    ),
+  };
+}
+
+// ── app_volume tests ──────────────────────────────────────────────────────────
+
+describe('KnobCard — app_volume', () => {
+  it('renders a datalist with the supplied running apps', () => {
+    renderCard({ action: 'app_volume' }, ['spotify', 'vlc', 'brave']);
+
+    // An input with a list attribute is promoted to combobox by jsdom; query
+    // by label text instead to avoid coupling to the ARIA role inference.
+    const input = screen.getByLabelText<HTMLInputElement>('Target');
+    const datalistId = input.getAttribute('list');
+    expect(datalistId).toBeTruthy();
+
+    const datalist = document.getElementById(datalistId!);
+    expect(datalist).toBeInTheDocument();
+    expect(datalist!.querySelectorAll('option')).toHaveLength(3);
+    const values = Array.from(datalist!.querySelectorAll('option')).map(
+      (o) => (o as HTMLOptionElement).value,
+    );
+    expect(values).toEqual(['spotify', 'vlc', 'brave']);
+  });
+
+  it('does not attach a datalist when runningApps is empty', () => {
+    renderCard({ action: 'app_volume' }, []);
+
+    const input = screen.getByLabelText<HTMLInputElement>('Target');
+    expect(input.getAttribute('list')).toBeNull();
+  });
+
+  it('does not attach a datalist when runningApps is not provided', () => {
+    renderCard({ action: 'app_volume' }, undefined);
+
+    const input = screen.getByLabelText<HTMLInputElement>('Target');
+    expect(input.getAttribute('list')).toBeNull();
+  });
+
+  it('calls onChange with the typed/selected value when the input changes', () => {
+    const onChange = vi.fn();
+    renderCard({ action: 'app_volume', target: 'default' }, ['spotify'], onChange);
+
+    // fireEvent.change is appropriate for a controlled input: we simulate
+    // the browser firing a change event with the full desired value.
+    fireEvent.change(screen.getByLabelText('Target'), {
+      target: { value: 'brave' },
+    });
+
+    const lastCall = onChange.mock.calls.at(-1)![0] as KnobConfig;
+    expect(lastCall.target).toBe('brave');
+  });
+});
+
+// ── group_volume tests ────────────────────────────────────────────────────────
+
+describe('KnobCard — group_volume', () => {
+  it('renders the app-picker select with running apps', () => {
+    renderCard({ action: 'group_volume', targets: [] }, ['vlc', 'brave']);
+
+    // The placeholder option + 2 apps
+    const select = screen.getByRole<HTMLSelectElement>('combobox', {
+      name: /pick a running app/i,
+    });
+    expect(select).toBeInTheDocument();
+    const options = Array.from(select.options).slice(1); // skip placeholder
+    expect(options.map((o) => o.value)).toEqual(['vlc', 'brave']);
+  });
+
+  it('does not render the app-picker when runningApps is empty', () => {
+    renderCard({ action: 'group_volume', targets: [] }, []);
+
+    expect(
+      screen.queryByRole('combobox', { name: /pick a running app/i }),
+    ).not.toBeInTheDocument();
+  });
+
+  it('does not render the app-picker when runningApps is not provided', () => {
+    renderCard({ action: 'group_volume', targets: [] }, undefined);
+
+    expect(
+      screen.queryByRole('combobox', { name: /pick a running app/i }),
+    ).not.toBeInTheDocument();
+  });
+
+  it('Add button is disabled until an app is selected from the dropdown', () => {
+    renderCard({ action: 'group_volume', targets: [] }, ['spotify']);
+
+    const addBtn = screen.getByRole('button', { name: /add/i });
+    expect(addBtn).toBeDisabled();
+  });
+
+  it('Add button becomes enabled after selecting an app', async () => {
+    renderCard({ action: 'group_volume', targets: [] }, ['spotify']);
+
+    const select = screen.getByRole('combobox', { name: /pick a running app/i });
+    await userEvent.selectOptions(select, 'spotify');
+
+    expect(screen.getByRole('button', { name: /add/i })).toBeEnabled();
+  });
+
+  it('clicking Add appends the selected app to targets', async () => {
+    const onChange = vi.fn();
+    renderCard({ action: 'group_volume', targets: ['vlc'] }, ['spotify', 'brave'], onChange);
+
+    const select = screen.getByRole('combobox', { name: /pick a running app/i });
+    await userEvent.selectOptions(select, 'brave');
+    await userEvent.click(screen.getByRole('button', { name: /add/i }));
+
+    const lastCall = onChange.mock.calls.at(-1)![0] as KnobConfig;
+    expect(lastCall.targets).toEqual(['vlc', 'brave']);
+  });
+
+  it('clicking Add does not add a duplicate app', async () => {
+    const onChange = vi.fn();
+    renderCard({ action: 'group_volume', targets: ['brave'] }, ['spotify', 'brave'], onChange);
+
+    const select = screen.getByRole('combobox', { name: /pick a running app/i });
+    await userEvent.selectOptions(select, 'brave');
+    await userEvent.click(screen.getByRole('button', { name: /add/i }));
+
+    const lastCall = onChange.mock.calls.at(-1);
+    // onChange should not have been called at all (duplicate guard)
+    expect(lastCall).toBeUndefined();
+  });
+
+  it('resets the picker select back to placeholder after a successful Add', async () => {
+    renderCard({ action: 'group_volume', targets: [] }, ['spotify']);
+
+    const select = screen.getByRole<HTMLSelectElement>('combobox', {
+      name: /pick a running app/i,
+    });
+    await userEvent.selectOptions(select, 'spotify');
+    await userEvent.click(screen.getByRole('button', { name: /add/i }));
+
+    expect(select.value).toBe('');
+  });
+});

ui/src/__tests__/api.test.ts

@@ -0,0 +1,52 @@
+/**
+ * Tests for the fetchRunningApps API helper.
+ *
+ * fetchRunningApps wraps GET /api/apps and is intentionally non-throwing:
+ * - returns the parsed JSON array on success
+ * - returns [] when the server responds with a non-2xx status
+ * - returns [] when the network call itself throws (e.g. server not reachable)
+ */
+
+import { fetchRunningApps } from '../api';
+
+const mockFetch = vi.fn<typeof fetch>();
+vi.stubGlobal('fetch', mockFetch);
+
+afterEach(() => {
+  mockFetch.mockReset();
+});
+
+function makeResponse(body: unknown, ok = true, status = 200): Response {
+  return {
+    ok,
+    status,
+    json: () => Promise.resolve(body),
+  } as unknown as Response;
+}
+
+describe('fetchRunningApps', () => {
+  it('returns a sorted list of app names on a successful response', async () => {
+    mockFetch.mockResolvedValue(makeResponse(['vlc', 'brave', 'spotify']));
+
+    const result = await fetchRunningApps();
+
+    expect(mockFetch).toHaveBeenCalledWith('/api/apps');
+    expect(result).toEqual(['vlc', 'brave', 'spotify']);
+  });
+
+  it('returns an empty array when the server responds with a non-ok status', async () => {
+    mockFetch.mockResolvedValue(makeResponse(null, false, 500));
+
+    const result = await fetchRunningApps();
+
+    expect(result).toEqual([]);
+  });
+
+  it('returns an empty array when fetch throws (network error)', async () => {
+    mockFetch.mockRejectedValue(new TypeError('Failed to fetch'));
+
+    const result = await fetchRunningApps();
+
+    expect(result).toEqual([]);
+  });
+});

ui/src/api.ts

@@ -56,3 +56,13 @@ export async function deletePreset(name: string): Promise<void> {
   });
   await checkResponse(r);
 }
+
+export async function fetchRunningApps(): Promise<string[]> {
+  try {
+    const r = await fetch('/api/apps');
+    if (!r.ok) return [];
+    return r.json();
+  } catch {
+    return [];
+  }
+}

ui/src/components/KnobCard.tsx

@@ -16,13 +16,15 @@ const DEFAULT_LED: LedConfig = {
 };
 
 interface Props {
-  index:    number;
-  knob:     KnobConfig;
-  onChange: (knob: KnobConfig) => void;
+  index:        number;
+  knob:         KnobConfig;
+  runningApps?: string[];
+  onChange:     (knob: KnobConfig) => void;
 }
 
-export function KnobCard({ index, knob, onChange }: Props) {
-  const [ledOpen, setLedOpen] = useState(!!knob.led);
+export function KnobCard({ index, knob, runningApps = [], onChange }: Props) {
+  const [ledOpen,      setLedOpen]      = useState(!!knob.led);
+  const [pickedApp,    setPickedApp]    = useState('');
 
   const update = (patch: Partial<KnobConfig>) => onChange({ ...knob, ...patch });
 
@@ -45,6 +47,19 @@ export function KnobCard({ index, knob, onChange }: Props) {
     }
   };
 
+  const datalistId = `knob-${index}-apps`;
+
+  // Add the selected running app to the group_volume targets list
+  const addPickedApp = () => {
+    const app = pickedApp.trim();
+    if (!app) return;
+    const current = knob.targets ?? [];
+    if (!current.includes(app)) {
+      update({ targets: [...current, app] });
+    }
+    setPickedApp('');
+  };
+
   return (
     <div className="knob-card">
       <div className="card-title">
@@ -87,6 +102,28 @@ export function KnobCard({ index, knob, onChange }: Props) {
               })
             }
           />
+          {runningApps.length > 0 && (
+            <div className="app-picker">
+              <select
+                value={pickedApp}
+                onChange={(e) => setPickedApp(e.target.value)}
+                aria-label="Pick a running app"
+              >
+                <option value="">— running apps —</option>
+                {runningApps.map((app) => (
+                  <option key={app} value={app}>{app}</option>
+                ))}
+              </select>
+              <button
+                type="button"
+                className="btn-secondary"
+                onClick={addPickedApp}
+                disabled={!pickedApp}
+              >
+                Add
+              </button>
+            </div>
+          )}
         </div>
       ) : (
         <div>
@@ -94,10 +131,18 @@ export function KnobCard({ index, knob, onChange }: Props) {
           <input
             type="text"
             id={`knob-${index}-target`}
+            list={runningApps.length > 0 ? datalistId : undefined}
             value={knob.target ?? 'default'}
             placeholder="default"
             onChange={(e) => update({ target: e.target.value })}
           />
+          {runningApps.length > 0 && (
+            <datalist id={datalistId}>
+              {runningApps.map((app) => (
+                <option key={app} value={app} />
+              ))}
+            </datalist>
+          )}
         </div>
       )}
 

ui/src/index.css

@@ -354,3 +354,35 @@ main {
   main { padding: 16px; }
   #app-header { padding: 10px 16px; }
 }
+
+/* ── Running-apps refresh button (Knobs section heading) ───────────────────── */
+#knobs h2 {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+}
+
+.btn-refresh-apps {
+  padding: 3px 10px;
+  font-size: 11px;
+  font-weight: 500;
+  letter-spacing: normal;
+  text-transform: none;
+}
+
+/* ── App picker (group_volume) ─────────────────────────────────────────────── */
+.app-picker {
+  display: flex;
+  gap: 6px;
+  margin-top: 6px;
+}
+
+.app-picker select {
+  flex: 1;
+  min-width: 0;
+}
+
+.app-picker .btn-secondary {
+  flex-shrink: 0;
+  padding: 7px 12px;
+}

ui/src/test-setup.ts

@@ -0,0 +1 @@
+import '@testing-library/jest-dom';

ui/tsconfig.app.json

@@ -5,7 +5,7 @@
     "useDefineForClassFields": true,
     "lib": ["ES2022", "DOM", "DOM.Iterable"],
     "module": "ESNext",
-    "types": ["vite/client"],
+    "types": ["vite/client", "vitest/globals"],
     "skipLibCheck": true,
 
     /* Bundler mode */

ui/vite.config.ts

@@ -14,4 +14,9 @@ export default defineConfig({
       '/api': 'http://localhost:5173',
     },
   },
+  test: {
+    environment: 'jsdom',
+    globals: true,
+    setupFiles: ['./src/test-setup.ts'],
+  },
 })