monitor-config-manager: Add support for suggested configuration

Create a suggested configuration, if such configuration is provided.

https://bugzilla.gnome.org/show_bug.cgi?id=777732

src/backends/meta-monitor-config-manager.c

@@ -24,6 +24,7 @@
 #include "backends/meta-monitor-config-manager.h"
 
 #include "backends/meta-monitor-manager-private.h"
+#include "core/boxes-private.h"
 
 struct _MetaMonitorConfigManager
 {
@@ -40,6 +41,9 @@ G_DEFINE_TYPE (MetaMonitorConfigManager, meta_monitor_config_manager,
 G_DEFINE_TYPE (MetaMonitorsConfig, meta_monitors_config,
                G_TYPE_OBJECT)
 
+static void
+meta_logical_monitor_config_free (MetaLogicalMonitorConfig *logical_monitor_config);
+
 MetaMonitorConfigManager *
 meta_monitor_config_manager_new (MetaMonitorManager *monitor_manager)
 {
@@ -449,6 +453,73 @@ meta_monitor_config_manager_create_fallback (MetaMonitorConfigManager *config_ma
   return config;
 }
 
+MetaMonitorsConfig *
+meta_monitor_config_manager_create_suggested (MetaMonitorConfigManager *config_manager)
+{
+  MetaMonitorManager *monitor_manager = config_manager->monitor_manager;
+  MetaMonitorsConfig *config;
+  MetaLogicalMonitorConfig *primary_logical_monitor_config = NULL;
+  MetaMonitor *primary_monitor;
+  GList *logical_monitor_configs;
+  GList *region;
+  GList *monitors;
+  GList *l;
+
+  primary_monitor = find_primary_monitor (monitor_manager);
+  if (!primary_monitor)
+    return NULL;
+
+  logical_monitor_configs = NULL;
+  region = NULL;
+  monitors = meta_monitor_manager_get_monitors (monitor_manager);
+  for (l = monitors; l; l = l->next)
+    {
+      MetaMonitor *monitor = l->data;
+      MetaLogicalMonitorConfig *logical_monitor_config;
+      int x, y;
+
+      if (!meta_monitor_get_suggested_position (monitor, &x, &y))
+        continue;
+
+      logical_monitor_config =
+        create_preferred_logical_monitor_config (monitor, x, y);
+      logical_monitor_configs = g_list_append (logical_monitor_configs,
+                                               logical_monitor_config);
+
+      if (meta_rectangle_overlaps_with_region (region,
+                                               &logical_monitor_config->layout))
+        {
+          g_warning ("Suggested monitor config has overlapping region, rejecting");
+          g_list_free (region);
+          g_list_free_full (logical_monitor_configs,
+                            (GDestroyNotify) meta_logical_monitor_config_free);
+          return NULL;
+        }
+
+      region = g_list_prepend (region, &logical_monitor_config->layout);
+
+      if (monitor == primary_monitor)
+        primary_logical_monitor_config = logical_monitor_config;
+    }
+
+  g_list_free (region);
+
+  if (!logical_monitor_configs)
+    return NULL;
+
+  if (!primary_logical_monitor_config)
+    primary_logical_monitor_config =
+      g_list_first (logical_monitor_configs)->data;
+
+  primary_logical_monitor_config->is_primary = TRUE;
+
+  config = g_object_new (META_TYPE_MONITORS_CONFIG, NULL);
+
+  config->logical_monitor_configs = logical_monitor_configs;
+
+  return config;
+}
+
 void
 meta_monitor_config_manager_set_current (MetaMonitorConfigManager *config_manager,
                                          MetaMonitorsConfig       *config)

src/backends/meta-monitor-config-manager.h

@@ -66,6 +66,8 @@ MetaMonitorsConfig * meta_monitor_config_manager_create_linear (MetaMonitorConfi
 
 MetaMonitorsConfig * meta_monitor_config_manager_create_fallback (MetaMonitorConfigManager *config_manager);
 
+MetaMonitorsConfig * meta_monitor_config_manager_create_suggested (MetaMonitorConfigManager *config_manager);
+
 void meta_monitor_config_manager_set_current (MetaMonitorConfigManager *config_manager,
                                               MetaMonitorsConfig       *config);
 

src/backends/meta-monitor-manager.c

@@ -332,6 +332,22 @@ meta_monitor_manager_ensure_configured (MetaMonitorManager *manager)
       return NULL;
     }
 
+  config = meta_monitor_config_manager_create_suggested (manager->config_manager);
+  if (config)
+    {
+      if (!meta_monitor_manager_apply_monitors_config (manager, config, &error))
+        {
+          g_clear_object (&config);
+          g_warning ("Failed to use suggested monitor configuration: %s",
+                     error->message);
+          g_clear_error (&error);
+        }
+      else
+        {
+          goto done;
+        }
+    }
+
   config = meta_monitor_config_manager_create_linear (manager->config_manager);
   if (!meta_monitor_manager_apply_monitors_config (manager, config, &error))
     {