[gnome-software/1801-flatpak-is-launched-while-displaying-a-native-app] gs-plugin: Add helper function gs_plugin_app_launch_filtered()

[Milan Crha <mcrha src gnome org>]

commit 912d9af9f44c7b92c3d8cc8fb1e4de705df9234d
Author: Milan Crha <mcrha redhat com>
Date:   Thu Jun 23 10:38:28 2022 +0200

    gs-plugin: Add helper function gs_plugin_app_launch_filtered()
    
    It can be used to pick which .desktop file should be used to launch
    an application. It helps to pick the right format when an application
    is installed by multiple repos/remotes, like as an RPM and as a Flatpak.

 lib/gs-plugin.c | 125 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 lib/gs-plugin.h |  24 +++++++++++
 2 files changed, 149 insertions(+)
---
diff --git a/lib/gs-plugin.c b/lib/gs-plugin.c
index 2fe17134a..c059ade99 100644
--- a/lib/gs-plugin.c
+++ b/lib/gs-plugin.c
@@ -892,6 +892,131 @@ gs_plugin_app_launch (GsPlugin *plugin, GsApp *app, GError **error)
        return TRUE;
 }
 
+static GDesktopAppInfo *
+check_directory_for_desktop_file (GsPlugin *plugin,
+                                 GsApp *app,
+                                 GsPluginPickDesktopFileCallback cb,
+                                 gpointer user_data,
+                                 const gchar *desktop_id,
+                                 const gchar *data_dir)
+{
+       g_autofree gchar *filename = NULL;
+       g_autoptr(GKeyFile) key_file = NULL;
+
+       filename = g_build_filename (data_dir, "applications", desktop_id, NULL);
+       key_file = g_key_file_new ();
+
+       if (g_key_file_load_from_file (key_file, filename, G_KEY_FILE_KEEP_TRANSLATIONS, NULL) &&
+           cb (plugin, app, filename, key_file)) {
+               g_autoptr(GDesktopAppInfo) appinfo = NULL;
+               appinfo = g_desktop_app_info_new_from_keyfile (key_file);
+               if (appinfo != NULL)
+                       return g_steal_pointer (&appinfo);
+               g_debug ("Failed to load '%s' as a GDesktopAppInfo", filename);
+               return NULL;
+       }
+
+       if (!g_str_has_suffix (desktop_id, ".desktop")) {
+               g_autofree gchar *desktop_filename = g_strconcat (filename, ".desktop", NULL);
+               if (g_key_file_load_from_file (key_file, desktop_filename, G_KEY_FILE_KEEP_TRANSLATIONS, 
NULL) &&
+                   cb (plugin, app, desktop_filename, key_file)) {
+                       g_autoptr(GDesktopAppInfo) appinfo = NULL;
+                       appinfo = g_desktop_app_info_new_from_keyfile (key_file);
+                       if (appinfo != NULL)
+                               return g_steal_pointer (&appinfo);
+                       g_debug ("Failed to load '%s' as a GDesktopAppInfo", desktop_filename);
+                       return NULL;
+               }
+       }
+
+       return NULL;
+}
+
+/**
+ * gs_plugin_app_launch_filtered:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp to launch
+ * @cb: a callback to pick the correct .desktop file
+ * @user_data: (closure cb) (scope call): user data for the @cb
+ * @error: a #GError, or %NULL
+ *
+ * Launches application @app, using the .desktop file picked by the @cb.
+ * This can help in case multiple versions of the @app are installed
+ * in the system (like a Flatpak and RPM versions).
+ *
+ * Returns: %TRUE on success
+ *
+ * Since: 43
+ **/
+gboolean
+gs_plugin_app_launch_filtered (GsPlugin *plugin,
+                              GsApp *app,
+                              GsPluginPickDesktopFileCallback cb,
+                              gpointer user_data,
+                              GError **error)
+{
+       const gchar *desktop_id;
+       g_autoptr(GDesktopAppInfo) appinfo = NULL;
+
+       g_return_val_if_fail (GS_IS_PLUGIN (plugin), FALSE);
+       g_return_val_if_fail (GS_IS_APP (app), FALSE);
+       g_return_val_if_fail (cb != NULL, FALSE);
+
+       desktop_id = gs_app_get_launchable (app, AS_LAUNCHABLE_KIND_DESKTOP_ID);
+       if (desktop_id == NULL)
+               desktop_id = gs_app_get_id (app);
+       if (desktop_id == NULL) {
+               g_set_error (error,
+                            GS_PLUGIN_ERROR,
+                            GS_PLUGIN_ERROR_NOT_SUPPORTED,
+                            "no desktop file for app: %s",
+                            gs_app_get_name (app));
+               return FALSE;
+       }
+
+       /* First, the configs.  Highest priority: the user's ~/.config */
+       appinfo = check_directory_for_desktop_file (plugin, app, cb, user_data, desktop_id, 
g_get_user_config_dir ());
+
+       if (appinfo == NULL) {
+               /* Next, the system configs (/etc/xdg, and so on). */
+               const gchar * const *dirs;
+               dirs = g_get_system_config_dirs ();
+               for (guint i = 0; dirs[i] && appinfo == NULL; i++) {
+                       appinfo = check_directory_for_desktop_file (plugin, app, cb, user_data, desktop_id, 
dirs[i]);
+               }
+       }
+
+       if (appinfo == NULL) {
+               /* Now the data.  Highest priority: the user's ~/.local/share/applications */
+               appinfo = check_directory_for_desktop_file (plugin, app, cb, user_data, desktop_id, 
g_get_user_data_dir ());
+       }
+
+       if (appinfo == NULL) {
+               /* Following that, XDG_DATA_DIRS/applications, in order */
+               const gchar * const *dirs;
+               dirs = g_get_system_data_dirs ();
+               for (guint i = 0; dirs[i] && appinfo == NULL; i++) {
+                       appinfo = check_directory_for_desktop_file (plugin, app, cb, user_data, desktop_id, 
dirs[i]);
+               }
+       }
+
+       if (appinfo == NULL) {
+               g_set_error (error,
+                            GS_PLUGIN_ERROR,
+                            GS_PLUGIN_ERROR_NOT_SUPPORTED,
+                            "no appropriate desktop file found: %s",
+                            desktop_id);
+               return FALSE;
+       }
+
+       g_idle_add_full (G_PRIORITY_DEFAULT,
+                        gs_plugin_app_launch_cb,
+                        g_object_ref (appinfo),
+                        (GDestroyNotify) g_object_unref);
+
+       return TRUE;
+}
+
 static void
 weak_ref_free (GWeakRef *weak)
 {
diff --git a/lib/gs-plugin.h b/lib/gs-plugin.h
index 709819799..412b2e734 100644
--- a/lib/gs-plugin.h
+++ b/lib/gs-plugin.h
@@ -208,6 +208,30 @@ void                gs_plugin_status_update                (GsPlugin       *plugin,
 gboolean        gs_plugin_app_launch                   (GsPlugin       *plugin,
                                                         GsApp          *app,
                                                         GError         **error);
+typedef gboolean (* GsPluginPickDesktopFileCallback)   (GsPlugin       *plugin,
+                                                        GsApp          *app,
+                                                        const gchar    *filename,
+                                                        GKeyFile       *key_file);
+/**
+ * GsPluginPickDesktopFileCallback:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ * @filename: a .desktop file name
+ * @key_file: a #GKeyFile with @filename loaded
+ *
+ * A callback used by gs_plugin_app_launch_filtered() to filter which
+ * of the candidate .desktop files should be used to launch the @app.
+ *
+ * Returns: %TRUE, when the @key_file should be used, %FALSE to continue
+ *    searching.
+ *
+ * Since: 43
+ **/
+gboolean        gs_plugin_app_launch_filtered          (GsPlugin       *plugin,
+                                                        GsApp          *app,
+                                                        GsPluginPickDesktopFileCallback cb,
+                                                        gpointer       user_data,
+                                                        GError         **error);
 void            gs_plugin_updates_changed              (GsPlugin       *plugin);
 void            gs_plugin_reload                       (GsPlugin       *plugin);
 const gchar    *gs_plugin_status_to_string             (GsPluginStatus  status);