feat: rewrite getVisibleSessions() to honor active view (task-2)

- Add _activeView state variable with default 'all' in App state section
- Rewrite getVisibleSessions() to filter by active view:
  - 'all' view: excludes hidden sessions
  - 'hidden' view: shows only hidden sessions
  - user view: filters to view's sessions list using sessionKey
  - Falls back to 'all' if active view no longer exists
- Add _getActiveView() and _setActiveView() test helpers
- Export new test helpers in window.MuxplexApp (module.exports)
- Add 6 new tests covering all acceptance criteria

Tests added:
- test_active_view_state_variable_exists
- test_get_visible_sessions_all_view_excludes_hidden
- test_get_visible_sessions_hidden_view_shows_hidden
- test_get_visible_sessions_user_view_filters_by_session_key
- test_get_active_view_helper_exported
- test_set_active_view_helper_exported

All 220 tests pass.

muxplex/frontend/app.js

@@ -137,6 +137,7 @@ let _settingsOpen = false;
 let _serverSettings = null;
 let _gridViewMode = 'flat';
 let _activeFilterDevice = 'all';
+let _activeView = 'all';
 const DISPLAY_DEFAULTS = {
   fontSize: 14,
   hoverPreviewDelay: 1500,
@@ -531,18 +532,45 @@ function buildStatusTileHTML(deviceName, statusText, statusClass) {
 }
 
 /**
- * Returns sessions with hidden session names removed.
+ * Returns sessions filtered by the active view.
- * Hides any session whose name appears in the hidden_sessions list,
+ *
- * regardless of whether it is local or remote (federated).
+ * - 'all' view:    excludes hidden sessions (sessions in hidden_sessions list)
- * Consolidates the hidden-session filter used by all render paths.
+ * - 'hidden' view: shows only hidden sessions
+ * - user view:     shows only sessions whose sessionKey is in that view's sessions list
+ *
+ * Status entries (unreachable, auth_failed, empty) are always excluded —
+ * they are rendered separately as status tiles.
+ *
+ * Falls back to 'all' behaviour if the active view no longer exists.
+ *
  * @param {object[]} sessions
  * @returns {object[]}
  */
 function getVisibleSessions(sessions) {
   var hidden = (_serverSettings && _serverSettings.hidden_sessions) || [];
+  var views = (_serverSettings && _serverSettings.views) || [];
+  var view = _resolveActiveView(_activeView, views);
+
   return (sessions || []).filter(function(s) {
-    // Skip status entries (unreachable, auth_failed) — rendered separately as status tiles
+    // Skip status entries (unreachable, auth_failed, empty) — rendered separately as status tiles
     if (s.status) return false;
+
+    if (view === 'hidden') {
+      // 'hidden' view: only show sessions that are in the hidden list
+      return hidden.length > 0 && (hidden.includes(s.sessionKey || s.name) || hidden.includes(s.name));
+    }
+
+    if (view !== 'all') {
+      // User-defined view: show only sessions whose sessionKey is in this view's sessions list
+      var userView = views.find(function(v) { return v.name === view; });
+      if (userView) {
+        var viewSessions = userView.sessions || [];
+        return viewSessions.includes(s.sessionKey || s.name) || viewSessions.includes(s.name);
+      }
+      // View no longer exists — fall through to 'all' behaviour
+    }
+
+    // 'all' view: exclude hidden sessions
     if (hidden.length > 0 && (hidden.includes(s.sessionKey || s.name) || hidden.includes(s.name))) {
       return false;
     }
@@ -2499,6 +2527,12 @@ function _setActiveFilterDevice(device) {
   _activeFilterDevice = device;
 }
 
+/** Test-only: get current _activeView value. */
+function _getActiveView() { return _activeView; }
+
+/** Test-only: set _activeView directly. */
+function _setActiveView(view) { _activeView = view; }
+
 // Recalculate fit layout on window resize
 window.addEventListener('resize', function() {
   var ds = getDisplaySettings();
@@ -2625,5 +2659,7 @@ if (typeof module !== 'undefined' && module.exports) {
     _getGridViewMode,
     _setGridViewMode,
     _setActiveFilterDevice,
+    _getActiveView,
+    _setActiveView,
   };
 }

muxplex/tests/test_frontend_js.py

@@ -3010,3 +3010,86 @@ def test_settings_hidden_sessions_uses_session_key() -> None:
         "(with s.name fallback) as the checkbox value so remote sessions are "
         "stored in device_id:name format in hidden_sessions"
     )
+
+
+# ---------------------------------------------------------------------------
+# Active view state variable and getVisibleSessions (task-2-active-view)
+# ---------------------------------------------------------------------------
+
+
+def test_active_view_state_variable_exists() -> None:
+    """_activeView state variable must be declared with default 'all'."""
+    assert "let _activeView = 'all'" in _JS, (
+        "let _activeView = 'all' must be declared in the App state section of app.js"
+    )
+
+
+def test_get_visible_sessions_all_view_excludes_hidden() -> None:
+    """getVisibleSessions must reference _activeView to honour the active view."""
+    match = re.search(
+        r"function getVisibleSessions\(sessions\)\s*\{(.*?)\n\}",
+        _JS,
+        re.DOTALL,
+    )
+    assert match, "getVisibleSessions function not found"
+    body = match.group(1)
+    assert "_activeView" in body, (
+        "getVisibleSessions must check _activeView to filter sessions by view"
+    )
+
+
+def test_get_visible_sessions_hidden_view_shows_hidden() -> None:
+    """getVisibleSessions must handle the 'hidden' view case."""
+    match = re.search(
+        r"function getVisibleSessions\(sessions\)\s*\{(.*?)\n\}",
+        _JS,
+        re.DOTALL,
+    )
+    assert match, "getVisibleSessions function not found"
+    body = match.group(1)
+    assert "'hidden'" in body or '"hidden"' in body, (
+        "getVisibleSessions must explicitly handle the 'hidden' view (show only hidden sessions)"
+    )
+
+
+def test_get_visible_sessions_user_view_filters_by_session_key() -> None:
+    """getVisibleSessions must use sessionKey when filtering for a user-defined view."""
+    match = re.search(
+        r"function getVisibleSessions\(sessions\)\s*\{(.*?)\n\}",
+        _JS,
+        re.DOTALL,
+    )
+    assert match, "getVisibleSessions function not found"
+    body = match.group(1)
+    assert "sessionKey" in body, (
+        "getVisibleSessions must use sessionKey to match sessions against the user view's "
+        "sessions list"
+    )
+
+
+def test_get_active_view_helper_exported() -> None:
+    """window.MuxplexApp must export _getActiveView test helper."""
+    match = re.search(
+        r"module\.exports\s*=\s*\{(.*?)\};",
+        _JS,
+        re.DOTALL,
+    )
+    assert match, "module.exports block not found"
+    exports = match.group(1)
+    assert "_getActiveView" in exports, (
+        "module.exports must export _getActiveView test helper"
+    )
+
+
+def test_set_active_view_helper_exported() -> None:
+    """window.MuxplexApp must export _setActiveView test helper."""
+    match = re.search(
+        r"module\.exports\s*=\s*\{(.*?)\};",
+        _JS,
+        re.DOTALL,
+    )
+    assert match, "module.exports block not found"
+    exports = match.group(1)
+    assert "_setActiveView" in exports, (
+        "module.exports must export _setActiveView test helper"
+    )