From 4fe26944d889dcb054b44272fb4df9b91cc1f0c0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timotej=20=C5=A0ul=C3=ADk?= <timotej.sulik@gmail.com>
Date: Thu, 12 Jan 2023 02:17:08 +0100
Subject: [PATCH] display: Fix gaps when numbering unusable displays

---
 panels/display/cc-display-config.c | 39 +++++++++++++++++++++---------
 panels/display/cc-display-config.h |  1 +
 panels/display/cc-display-panel.c  |  3 +++
 3 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/panels/display/cc-display-config.c b/panels/display/cc-display-config.c
index b7532f99a..f2ccda522 100644
--- a/panels/display/cc-display-config.c
+++ b/panels/display/cc-display-config.c
@@ -465,7 +465,6 @@ cc_display_config_constructed (GObject *object)
   CcDisplayConfigPrivate *priv = cc_display_config_get_instance_private (self);
   GList *monitors = cc_display_config_get_monitors (self);
   GList *item;
-  gint ui_number = 1;
 
   for (item = monitors; item != NULL; item = item->next)
     {
@@ -477,16 +476,7 @@ cc_display_config_constructed (GObject *object)
         priv->ui_sorted_monitors = g_list_append (priv->ui_sorted_monitors, monitor);
     }
 
-  for (item = priv->ui_sorted_monitors; item != NULL; item = item->next)
-    {
-      CcDisplayMonitor *monitor = item->data;
-      char *ui_name;
-      ui_name = make_output_ui_name (monitor);
-
-      cc_display_monitor_set_ui_info (monitor, ui_number, ui_name);
-
-      ui_number += 1;
-    }
+  cc_display_config_update_ui_numbers_names(self);
 }
 
 static void
@@ -663,3 +653,30 @@ cc_display_config_get_panel_orientation_managed (CcDisplayConfig *self)
 {
   return CC_DISPLAY_CONFIG_GET_CLASS (self)->get_panel_orientation_managed (self);
 }
+
+void
+cc_display_config_update_ui_numbers_names (CcDisplayConfig *self)
+{
+  CcDisplayConfigPrivate *priv = cc_display_config_get_instance_private (self);
+  GList *item;
+  gint ui_number = 1;
+  for (item = priv->ui_sorted_monitors; item != NULL; item = item->next)
+    {
+      CcDisplayMonitor *monitor = item->data;
+      char *ui_name;
+      gint current_ui_number = 0;
+
+      ui_name = make_output_ui_name (monitor);
+
+      /* Prevents gaps in monitor numbering. Monitors
+       * with number 0 will not be visible in the UI.
+       */
+      if (cc_display_monitor_is_usable (monitor))
+        {
+          current_ui_number = ui_number;
+          ui_number += 1;
+        }
+
+      cc_display_monitor_set_ui_info (monitor, current_ui_number, ui_name);
+    }
+}
diff --git a/panels/display/cc-display-config.h b/panels/display/cc-display-config.h
index 1241adcd5..ea52c2d59 100644
--- a/panels/display/cc-display-config.h
+++ b/panels/display/cc-display-config.h
@@ -202,6 +202,7 @@ gboolean          cc_display_config_is_scaled_mode_valid    (CcDisplayConfig
                                                              double              scale);
 gboolean          cc_display_config_get_panel_orientation_managed
                                                             (CcDisplayConfig    *self);
+void              cc_display_config_update_ui_numbers_names (CcDisplayConfig    *self);
 
 const char*       cc_display_monitor_get_display_name       (CcDisplayMonitor   *monitor);
 gboolean          cc_display_monitor_is_active              (CcDisplayMonitor   *monitor);
diff --git a/panels/display/cc-display-panel.c b/panels/display/cc-display-panel.c
index cb460e361..a4d30a2fe 100644
--- a/panels/display/cc-display-panel.c
+++ b/panels/display/cc-display-panel.c
@@ -878,6 +878,9 @@ reset_current_config (CcDisplayPanel *panel)
           if (cc_display_monitor_is_builtin (output) && panel->lid_is_closed)
             cc_display_monitor_set_usable (output, FALSE);
         }
+
+      /* Recalculate UI numbers after the monitor usability is determined to skip numbering gaps. */
+      cc_display_config_update_ui_numbers_names(panel->current_config);
     }
 
   cc_display_arrangement_set_config (panel->arrangement, panel->current_config);