better structure

config/quickshell/Services/PanelService.qml

@@ -0,0 +1,67 @@
+pragma Singleton
+
+import Quickshell
+
+Singleton {
+  id: root
+
+  // A ref. to the lockScreen, so it's accessible from anywhere
+  // This is not a panel...
+  property var lockScreen: null
+
+  // Panels
+  property var registeredPanels: ({})
+  property var openedPanel: null
+  signal willOpen
+
+  // Currently opened popups, can have more than one.
+  // ex: when opening an NIconPicker from a widget setting.
+  property var openedPopups: []
+  property bool hasOpenedPopup: false
+  signal popupChanged
+
+  // Register this panel
+  function registerPanel(panel) {
+    registeredPanels[panel.objectName] = panel
+  }
+
+  // Returns a panel
+  function getPanel(name) {
+    return registeredPanels[name] || null
+  }
+
+  // Check if a panel exists
+  function hasPanel(name) {
+    return name in registeredPanels
+  }
+
+  // Helper to keep only one panel open at any time
+  function willOpenPanel(panel) {
+    if (openedPanel && openedPanel !== panel) {
+      openedPanel.close()
+    }
+    openedPanel = panel
+
+    // emit signal
+    willOpen()
+  }
+
+  function closedPanel(panel) {
+    if (openedPanel && openedPanel === panel) {
+      openedPanel = null
+    }
+  }
+
+  // Popups
+  function willOpenPopup(popup) {
+    openedPopups.push(popup)
+    hasOpenedPopup = (openedPopups.length !== 0)
+    popupChanged()
+  }
+
+  function willClosePopup(popup) {
+    openedPopups = openedPopups.filter(p => p !== popup)
+    hasOpenedPopup = (openedPopups.length !== 0)
+    popupChanged()
+  }
+}