clapper-gtk: seek-bar: Make custom markers colorful

Detect and auto switch thread to main if done from a different one.
With this, apps can still continue to implement thread switch and doing
multiple insertions/deletions within single main thread invoke or simply
call this function from a different thread for convenience.

COPYING-LGPL

@@ -2,7 +2,7 @@
                        Version 2.1, February 1999
 
  Copyright (C) 1991, 1999 Free Software Foundation, Inc.
- 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ <https://fsf.org/>
  Everyone is permitted to copy and distribute verbatim copies
  of this license document, but changing it is not allowed.
 
@@ -55,7 +55,7 @@ modified by someone else and passed on, the recipients should know
 that what they have is not the original version, so that the original
 author's reputation will not be affected by problems that might be
 introduced by others.
-
+
   Finally, software patents pose a constant threat to the existence of
 any free program.  We wish to make sure that a company cannot
 effectively restrict the users of a free program by obtaining a
@@ -111,7 +111,7 @@ modification follow.  Pay close attention to the difference between a
 "work based on the library" and a "work that uses the library".  The
 former contains code derived from the library, whereas the latter must
 be combined with the library in order to run.
-
+
                   GNU LESSER GENERAL PUBLIC LICENSE
    TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
 
@@ -158,7 +158,7 @@ Library.
   You may charge a fee for the physical act of transferring a copy,
 and you may at your option offer warranty protection in exchange for a
 fee.
-
+
   2. You may modify your copy or copies of the Library or any portion
 of it, thus forming a work based on the Library, and copy and
 distribute such modifications or work under the terms of Section 1
@@ -216,7 +216,7 @@ instead of to this License.  (If a newer version than version 2 of the
 ordinary GNU General Public License has appeared, then you can specify
 that version instead if you wish.)  Do not make any other change in
 these notices.
-
+
   Once this change is made in a given copy, it is irreversible for
 that copy, so the ordinary GNU General Public License applies to all
 subsequent copies and derivative works made from that copy.
@@ -267,7 +267,7 @@ Library will still fall under Section 6.)
 distribute the object code for the work under the terms of Section 6.
 Any executables containing that work also fall under Section 6,
 whether or not they are linked directly with the Library itself.
-
+
   6. As an exception to the Sections above, you may also combine or
 link a "work that uses the Library" with the Library to produce a
 work containing portions of the Library, and distribute that work
@@ -329,7 +329,7 @@ restrictions of other proprietary libraries that do not normally
 accompany the operating system.  Such a contradiction means you cannot
 use both them and the Library together in an executable that you
 distribute.
-
+
   7. You may place library facilities that are a work based on the
 Library side-by-side in a single library together with other library
 facilities not covered by this License, and distribute such a combined
@@ -370,7 +370,7 @@ subject to these terms and conditions.  You may not impose any further
 restrictions on the recipients' exercise of the rights granted herein.
 You are not responsible for enforcing compliance by third parties with
 this License.
-
+
   11. If, as a consequence of a court judgment or allegation of patent
 infringement or for any other reason (not limited to patent issues),
 conditions are imposed on you (whether by court order, agreement or
@@ -422,7 +422,7 @@ conditions either of that version or of any later version published by
 the Free Software Foundation.  If the Library does not specify a
 license version number, you may choose any version ever published by
 the Free Software Foundation.
-
+
   14. If you wish to incorporate parts of the Library into other free
 programs whose distribution conditions are incompatible with these,
 write to the author to ask for permission.  For software which is
@@ -456,7 +456,7 @@ SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
 DAMAGES.
 
                      END OF TERMS AND CONDITIONS
-
+
            How to Apply These Terms to Your New Libraries
 
   If you develop a new library, and you want it to be of the greatest
@@ -484,9 +484,7 @@ convey the exclusion of warranty; and each file should have at least the
     Lesser General Public License for more details.
 
     You should have received a copy of the GNU Lesser General Public
-    License along with this library; if not, write to the Free Software
-    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
-    USA
+    License along with this library; if not, see <https://www.gnu.org/licenses/>.
 
 Also add information on how to contact you by electronic and paper mail.
 
@@ -495,10 +493,9 @@ school, if any, to sign a "copyright disclaimer" for the library, if
 necessary.  Here is a sample; alter the names:
 
   Yoyodyne, Inc., hereby disclaims all copyright interest in the
-  library `Frob' (a library for tweaking knobs) written by James Random
-  Hacker.
+  library `Frob' (a library for tweaking knobs) written by James Random Hacker.
 
-  <signature of Ty Coon>, 1 April 1990
-  Ty Coon, President of Vice
+  <signature of Moe Ghoul>, 1 April 1990
+  Moe Ghoul, President of Vice
 
 That's all there is to it!

src/bin/clapper-app/clapper-app-window.c

@@ -86,9 +86,7 @@ typedef struct
   gint64 last_tick;
 } ClapperAppWindowResizeData;
 
-#if CLAPPER_HAVE_MPRIS
 static guint16 instance_count = 0;
-#endif
 
 static inline GQuark
 clapper_app_window_extra_options_get_quark (void)
@@ -1252,16 +1250,28 @@ clapper_app_window_constructed (GObject *object)
 #if (CLAPPER_HAVE_MPRIS || CLAPPER_HAVE_SERVER || CLAPPER_HAVE_DISCOVERER)
   ClapperFeature *feature = NULL;
 #endif
-#if CLAPPER_HAVE_MPRIS
+#if (!CLAPPER_HAVE_MPRIS || !CLAPPER_HAVE_SERVER || !CLAPPER_HAVE_DISCOVERER)
+  ClapperEnhancerProxyList *proxies = clapper_player_get_enhancer_proxies (player);
+  ClapperEnhancerProxy *proxy;
+#endif
+
   gchar mpris_name[45];
   g_snprintf (mpris_name, sizeof (mpris_name),
       "org.mpris.MediaPlayer2.Clapper.instance%" G_GUINT16_FORMAT, instance_count++);
-#endif
 
   self->settings = g_settings_new (CLAPPER_APP_ID);
   self->last_volume = PERCENTAGE_ROUND (g_settings_get_double (self->settings, "volume"));
 
-#if CLAPPER_HAVE_MPRIS
+#if !CLAPPER_HAVE_MPRIS
+  if ((proxy = clapper_enhancer_proxy_list_get_proxy_by_module (proxies, "clapper-mpris"))) {
+    clapper_enhancer_proxy_set_locally (proxy,
+        "own-name", mpris_name,
+        "identity", CLAPPER_APP_NAME,
+        "desktop-entry", CLAPPER_APP_ID,
+        "queue-controllable", TRUE, NULL);
+    gst_object_unref (proxy);
+  }
+#else
   feature = CLAPPER_FEATURE (clapper_mpris_new (
       mpris_name, CLAPPER_APP_NAME, CLAPPER_APP_ID));
   clapper_mpris_set_queue_controllable (CLAPPER_MPRIS (feature), TRUE);

src/bin/clapper-app/main.c

@@ -31,8 +31,10 @@
 gint
 main (gint argc, gchar **argv)
 {
-  const gchar *clapper_ldir;
   GApplication *application;
+  ClapperEnhancerProxyList *proxies;
+  const gchar *clapper_ldir;
+  guint i, n_proxies;
   gint status;
 
 #ifdef G_OS_WIN32
@@ -64,6 +66,15 @@ main (gint argc, gchar **argv)
   resolution = clapper_app_utils_win_hi_res_clock_start ();
 #endif
 
+  proxies = clapper_get_global_enhancer_proxies ();
+  n_proxies = clapper_enhancer_proxy_list_get_n_proxies (proxies);
+
+  /* Allow usage of all enhancers */
+  for (i = 0; i < n_proxies; ++i) {
+    ClapperEnhancerProxy *proxy = clapper_enhancer_proxy_list_peek_proxy (proxies, i);
+    clapper_enhancer_proxy_set_target_creation_allowed (proxy, TRUE);
+  }
+
   application = clapper_app_application_new ();
 
   status = g_application_run (application, argc, argv);

src/lib/clapper-gtk/clapper-gtk-billboard.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-billboard.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-buffering-animation-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-buffering-animation.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include <clapper/clapper.h>

src/lib/clapper-gtk/clapper-gtk-buffering-paintable-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-buffering-paintable.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "clapper-gtk-buffering-paintable-private.h"

src/lib/clapper-gtk/clapper-gtk-container-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-container.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-container.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-enums.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-extra-menu-button.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-extra-menu-button.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-lead-container.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-lead-container.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-limited-layout-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-limited-layout.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include <clapper/clapper.h>

src/lib/clapper-gtk/clapper-gtk-next-item-button.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-next-item-button.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-previous-item-button.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-previous-item-button.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-seek-bar.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**
@@ -396,6 +395,47 @@ _update_duration_label (ClapperGtkSeekBar *self, gdouble duration)
   gtk_adjustment_set_upper (adjustment, duration);
 }
 
+static gboolean
+_find_marks_in_widget (GtkWidget *widget, GtkWidget **top_marks, GtkWidget **bottom_marks)
+{
+  GtkWidget *child;
+
+  if (g_strcmp0 (gtk_widget_get_css_name (widget), "marks") == 0) {
+    if (gtk_widget_has_css_class (widget, "top"))
+      *top_marks = widget;
+    else if (gtk_widget_has_css_class (widget, "bottom"))
+      *bottom_marks = widget;
+
+    /* Its unexpected to have marks within marks,
+     * so do not iterate children of marks widget */
+    return (*top_marks && *bottom_marks);
+  }
+
+  child = gtk_widget_get_first_child (widget);
+
+  while (child != NULL) {
+    if (_find_marks_in_widget (child, top_marks, bottom_marks))
+      return TRUE;
+
+    child = gtk_widget_get_next_sibling (child);
+  }
+
+  return FALSE;
+}
+
+static gboolean
+_find_last_mark_in_marks (GtkWidget *marks, GtkWidget **last_mark)
+{
+  GtkWidget *widget = gtk_widget_get_last_child (marks);
+
+  if (widget && g_strcmp0 (gtk_widget_get_css_name (widget), "mark") == 0) {
+    *last_mark = widget;
+    return TRUE;
+  }
+
+  return FALSE;
+}
+
 static void
 _update_scale_marks (ClapperGtkSeekBar *self, ClapperTimeline *timeline)
 {
@@ -424,11 +464,43 @@ _update_scale_marks (ClapperGtkSeekBar *self, ClapperTimeline *timeline)
 
   for (i = 0; i < n_markers; ++i) {
     ClapperMarker *marker = clapper_timeline_get_marker (timeline, i);
+    ClapperMarkerType marker_type = clapper_marker_get_marker_type (marker);
     gdouble start = clapper_marker_get_start (marker);
 
     gtk_scale_add_mark (GTK_SCALE (self->scale), start, GTK_POS_TOP, NULL);
     gtk_scale_add_mark (GTK_SCALE (self->scale), start, GTK_POS_BOTTOM, NULL);
 
+    if (marker_type >= CLAPPER_MARKER_TYPE_CUSTOM_1) {
+      GtkWidget *top_marks = NULL, *bottom_marks = NULL;
+      GtkWidget *top_mark = NULL, *bottom_mark = NULL;
+
+      if (_find_marks_in_widget (self->scale, &top_marks, &bottom_marks)
+          && _find_last_mark_in_marks (top_marks, &top_mark)
+          && _find_last_mark_in_marks (bottom_marks, &bottom_mark)) {
+        const gchar *custom_name;
+
+        switch (marker_type) {
+          case CLAPPER_MARKER_TYPE_CUSTOM_1:
+            custom_name = "custom1";
+            break;
+          case CLAPPER_MARKER_TYPE_CUSTOM_2:
+            custom_name = "custom2";
+            break;
+          case CLAPPER_MARKER_TYPE_CUSTOM_3:
+            custom_name = "custom3";
+            break;
+          default:
+            custom_name = NULL;
+            break;
+        }
+
+        if (G_LIKELY (custom_name != NULL)) {
+          gtk_widget_add_css_class (top_mark, custom_name);
+          gtk_widget_add_css_class (bottom_mark, custom_name);
+        }
+      }
+    }
+
     gst_object_unref (marker);
   }
 

src/lib/clapper-gtk/clapper-gtk-seek-bar.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-simple-controls.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-simple-controls.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-status-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-status.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "config.h"

src/lib/clapper-gtk/clapper-gtk-stream-check-button-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-stream-check-button.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "config.h"

src/lib/clapper-gtk/clapper-gtk-title-header.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-title-header.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-title-label.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-title-label.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-toggle-fullscreen-button.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-toggle-fullscreen-button.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-toggle-play-button.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-toggle-play-button.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-utils-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-utils.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "config.h"

src/lib/clapper-gtk/clapper-gtk-utils.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-version.h.in

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-video-placeholder-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk-video-placeholder.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "config.h"

src/lib/clapper-gtk/clapper-gtk-video.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper-gtk/clapper-gtk-video.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/clapper-gtk.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper-gtk/css/styles.css

@@ -129,6 +129,15 @@ clapper-gtk-seek-bar label {
   margin-left: 2px;
   margin-right: 2px;
 }
+clapper-gtk-seek-bar scale marks .custom1 indicator {
+  color: tomato;
+}
+clapper-gtk-seek-bar scale marks .custom2 indicator {
+  color: goldenrod;
+}
+clapper-gtk-seek-bar scale marks .custom3 indicator {
+  color: limegreen;
+}
 
 clapper-gtk-extra-menu-button popover .spinsidebutton {
   min-width: 28px;

src/lib/clapper/clapper-app-bus-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-app-bus.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include <gio/gio.h>

src/lib/clapper/clapper-audio-stream-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-audio-stream.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper/clapper-audio-stream.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-basic-functions.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "config.h"
@@ -29,6 +28,7 @@
 #include "clapper-app-bus-private.h"
 #include "clapper-features-bus-private.h"
 #include "clapper-enhancer-proxy-list-private.h"
+#include "clapper-reactables-manager-private.h"
 #include "gst/clapper-plugin-private.h"
 
 #include "clapper-functionalities-availability.h"
@@ -56,6 +56,7 @@ clapper_init_check_internal (int *argc, char **argv[])
   clapper_playbin_bus_initialize ();
   clapper_app_bus_initialize ();
   clapper_features_bus_initialize ();
+  clapper_reactables_manager_initialize ();
 
   _proxies = clapper_enhancer_proxy_list_new_named ("global-proxy-list");
 

src/lib/clapper/clapper-basic-functions.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-bus-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-cache-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-cache.c

@@ -12,20 +12,21 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "clapper-cache-private.h"
 #include "clapper-version.h"
 #include "clapper-extractable.h"
+#include "clapper-reactable.h"
 
 #define CLAPPER_CACHE_HEADER "CLAPPER"
 
 typedef enum
 {
   CLAPPER_CACHE_IFACE_EXTRACTABLE = 1,
+  CLAPPER_CACHE_IFACE_REACTABLE,
 } ClapperCacheIfaces;
 
 static GArray *enum_registry = NULL;
@@ -243,6 +244,8 @@ clapper_cache_read_iface (const gchar **data)
   switch (iface_id) {
     case CLAPPER_CACHE_IFACE_EXTRACTABLE:
       return CLAPPER_TYPE_EXTRACTABLE;
+    case CLAPPER_CACHE_IFACE_REACTABLE:
+      return CLAPPER_TYPE_REACTABLE;
     default:
       return 0;
   }
@@ -433,6 +436,8 @@ clapper_cache_store_iface (GByteArray *bytes, GType iface)
 
   if (iface == CLAPPER_TYPE_EXTRACTABLE)
     iface_id = CLAPPER_CACHE_IFACE_EXTRACTABLE;
+  else if (iface == CLAPPER_TYPE_REACTABLE)
+    iface_id = CLAPPER_CACHE_IFACE_REACTABLE;
   else
     return FALSE;
 

src/lib/clapper/clapper-enhancer-proxy-list-private.h

@@ -12,14 +12,14 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once
 
 #include <glib.h>
+#include <glib-object.h>
 
 #include "clapper-enhancer-proxy-list.h"
 #include "clapper-enhancer-proxy.h"
@@ -38,4 +38,7 @@ void clapper_enhancer_proxy_list_fill_from_global_proxies (ClapperEnhancerProxyL
 G_GNUC_INTERNAL
 void clapper_enhancer_proxy_list_sort (ClapperEnhancerProxyList *list);
 
+G_GNUC_INTERNAL
+gboolean clapper_enhancer_proxy_list_has_proxy_with_interface (ClapperEnhancerProxyList *list, GType iface_type);
+
 G_END_DECLS

src/lib/clapper/clapper-enhancer-proxy-list.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**
@@ -161,6 +160,29 @@ clapper_enhancer_proxy_list_sort (ClapperEnhancerProxyList *self)
   g_ptr_array_sort_values (self->proxies, (GCompareFunc) _sort_values_by_name);
 }
 
+/*
+ * clapper_enhancer_proxy_list_has_proxy_with_interface:
+ * @iface_type: an interface #GType
+ *
+ * Check if any enhancer implementing given interface type is available.
+ *
+ * Returns: whether any enhancer proxy was found.
+ */
+gboolean
+clapper_enhancer_proxy_list_has_proxy_with_interface (ClapperEnhancerProxyList *self, GType iface_type)
+{
+  guint i;
+
+  for (i = 0; i < self->proxies->len; ++i) {
+    ClapperEnhancerProxy *proxy = clapper_enhancer_proxy_list_peek_proxy (self, i);
+
+    if (clapper_enhancer_proxy_target_has_interface (proxy, iface_type))
+      return TRUE;
+  }
+
+  return FALSE;
+}
+
 /**
  * clapper_enhancer_proxy_list_get_proxy:
  * @list: a #ClapperEnhancerProxyList

src/lib/clapper/clapper-enhancer-proxy-list.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-enhancer-proxy-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once
@@ -45,6 +44,9 @@ void clapper_enhancer_proxy_export_to_cache (ClapperEnhancerProxy *proxy);
 G_GNUC_INTERNAL
 GObject * clapper_enhancer_proxy_get_peas_info (ClapperEnhancerProxy *proxy);
 
+G_GNUC_INTERNAL
+gboolean clapper_enhancer_proxy_has_locally_set (ClapperEnhancerProxy *proxy, const gchar *property_name);
+
 G_GNUC_INTERNAL
 GstStructure * clapper_enhancer_proxy_make_current_config (ClapperEnhancerProxy *proxy);
 

src/lib/clapper/clapper-enhancer-proxy.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**
@@ -48,6 +47,9 @@
 #include "clapper-basic-functions.h"
 #include "clapper-cache-private.h"
 #include "clapper-extractable.h"
+#include "clapper-reactable.h"
+#include "clapper-player-private.h"
+#include "clapper-utils-private.h"
 #include "clapper-enums.h"
 
 #include "clapper-functionalities-availability.h"
@@ -84,6 +86,8 @@ struct _ClapperEnhancerProxy
   ClapperEnhancerParamFlags scope;
   GstStructure *local_config;
 
+  gboolean allowed;
+
   /* GSettings are not thread-safe,
    * so store schema instead */
   GSettingsSchema *schema;
@@ -98,6 +102,7 @@ enum
   PROP_MODULE_DIR,
   PROP_DESCRIPTION,
   PROP_VERSION,
+  PROP_TARGET_CREATION_ALLOWED,
   PROP_LAST
 };
 
@@ -213,7 +218,7 @@ clapper_enhancer_proxy_copy (ClapperEnhancerProxy *src_proxy, const gchar *copy_
   copy->pspecs = g_new (GParamSpec *, copy->n_pspecs);
 
   for (i = 0; i < src_proxy->n_pspecs; ++i)
-    copy->pspecs[i] = src_proxy->pspecs[i];
+    copy->pspecs[i] = g_param_spec_ref (src_proxy->pspecs[i]);
 
   copy->scope = CLAPPER_ENHANCER_PARAM_LOCAL;
 
@@ -227,6 +232,8 @@ clapper_enhancer_proxy_copy (ClapperEnhancerProxy *src_proxy, const gchar *copy_
   if (src_proxy->local_config)
     copy->local_config = gst_structure_copy (src_proxy->local_config);
 
+  copy->allowed = src_proxy->allowed;
+
   GST_OBJECT_UNLOCK (src_proxy);
 
   gst_object_ref_sink (copy);
@@ -357,6 +364,8 @@ clapper_enhancer_proxy_fill_from_cache (ClapperEnhancerProxy *self)
       if (G_UNLIKELY ((self->ifaces[i] = clapper_cache_read_iface (&data)) == 0))
         goto abort_reading;
     }
+    /* Reactable type is always last */
+    self->allowed = (self->ifaces[self->n_ifaces - 1] != CLAPPER_TYPE_REACTABLE);
   }
 
   /* Restore ParamSpecs */
@@ -454,7 +463,8 @@ clapper_enhancer_proxy_export_to_cache (ClapperEnhancerProxy *self)
 gboolean
 clapper_enhancer_proxy_fill_from_instance (ClapperEnhancerProxy *self, GObject *enhancer)
 {
-  GType enhancer_types[1] = { CLAPPER_TYPE_EXTRACTABLE };
+  /* NOTE: REACTABLE must be last for "allowed" to work as expected */
+  const GType enhancer_types[] = { CLAPPER_TYPE_EXTRACTABLE, CLAPPER_TYPE_REACTABLE };
   GType *ifaces;
   GParamSpec **pspecs;
   GParamFlags enhancer_flags;
@@ -463,9 +473,12 @@ clapper_enhancer_proxy_fill_from_instance (ClapperEnhancerProxy *self, GObject *
   /* Filter to only Clapper interfaces */
   ifaces = g_type_interfaces (G_OBJECT_TYPE (enhancer), &n);
   for (i = 0; i < n; ++i) {
-    for (j = 0; j < G_N_ELEMENTS (enhancer_types); ++j) {
+    const guint n_types = G_N_ELEMENTS (enhancer_types);
+
+    for (j = 0; j < n_types; ++j) {
       if (ifaces[i] == enhancer_types[j]) {
         ifaces[write_index++] = ifaces[i];
+        self->allowed = (j < n_types - 1);
         break; // match found, do next iface
       }
     }
@@ -500,6 +513,18 @@ clapper_enhancer_proxy_get_peas_info (ClapperEnhancerProxy *self)
   return self->peas_info;
 }
 
+gboolean
+clapper_enhancer_proxy_has_locally_set (ClapperEnhancerProxy *self, const gchar *property_name)
+{
+  gboolean has_field;
+
+  GST_OBJECT_LOCK (self);
+  has_field = (self->local_config && gst_structure_has_field (self->local_config, property_name));
+  GST_OBJECT_UNLOCK (self);
+
+  return has_field;
+}
+
 static gboolean
 _apply_config_cb (GQuark field_id, const GValue *value, GObject *enhancer)
 {
@@ -527,6 +552,7 @@ clapper_enhancer_proxy_make_current_config (ClapperEnhancerProxy *self)
 
     /* Using "has_field", as set value might be %NULL */
     if ((pspec->flags & CLAPPER_ENHANCER_PARAM_LOCAL)
+        && self->local_config
         && gst_structure_has_field (self->local_config, pspec->name)) {
       if (!merged_config)
         merged_config = gst_structure_new_empty (CONFIG_STRUCTURE_NAME);
@@ -540,44 +566,13 @@ clapper_enhancer_proxy_make_current_config (ClapperEnhancerProxy *self)
       GVariant *def = g_settings_get_default_value (settings, pspec->name);
 
       if (!g_variant_equal (val, def)) {
-        if (!merged_config)
-          merged_config = gst_structure_new_empty (CONFIG_STRUCTURE_NAME);
+        GValue value = G_VALUE_INIT;
 
-        switch (pspec->value_type) {
-          case G_TYPE_BOOLEAN:
-            gst_structure_set (merged_config, pspec->name,
-                pspec->value_type, g_variant_get_boolean (val), NULL);
-            break;
-          case G_TYPE_INT:
-            gst_structure_set (merged_config, pspec->name,
-                pspec->value_type, g_variant_get_int32 (val), NULL);
-            break;
-          case G_TYPE_UINT:
-            gst_structure_set (merged_config, pspec->name,
-                pspec->value_type, g_variant_get_uint32 (val), NULL);
-            break;
-          case G_TYPE_DOUBLE:
-            gst_structure_set (merged_config, pspec->name,
-                pspec->value_type, g_variant_get_double (val), NULL);
-            break;
-          case G_TYPE_STRING:
-            gst_structure_set (merged_config, pspec->name,
-                pspec->value_type, g_variant_get_string (val, NULL), NULL);
-            break;
-          default:{
-            if (G_IS_PARAM_SPEC_ENUM (pspec)) {
-              gst_structure_set (merged_config, pspec->name,
-                  G_TYPE_INT, g_variant_get_int32 (val), NULL);
-              break;
-            } else if (G_IS_PARAM_SPEC_FLAGS (pspec)) {
-              gst_structure_set (merged_config, pspec->name,
-                  G_TYPE_UINT, g_variant_get_uint32 (val), NULL);
-              break;
-            }
-            GST_ERROR_OBJECT (self, "Unsupported enhancer \"%s\" setting type: %s",
-                pspec->name, g_type_name (pspec->value_type));
-            break;
-          }
+        if (G_LIKELY (clapper_utils_set_value_from_variant (&value, val))) {
+          if (!merged_config)
+            merged_config = gst_structure_new_empty (CONFIG_STRUCTURE_NAME);
+
+          gst_structure_take_value (merged_config, pspec->name, &value);
         }
       }
 
@@ -706,7 +701,7 @@ clapper_enhancer_proxy_get_version (ClapperEnhancerProxy *self)
  *
  * Get extra data from enhancer plugin info file specified by @key.
  *
- * External data in the plugin info file is prefixed with `X-`.
+ * Extra data in the plugin info file is prefixed with `X-`.
  * For example `X-Schemes=https`.
  *
  * Returns: (nullable): extra data value of the proxied enhancer.
@@ -740,6 +735,10 @@ clapper_enhancer_proxy_get_extra_data (ClapperEnhancerProxy *self, const gchar *
  * calling this function with "X-Schemes" as key and "http" as value will
  * return %TRUE.
  *
+ * It is also safe to call this function when there is no such @key
+ * in plugin info file. Use [method@Clapper.EnhancerProxy.get_extra_data]
+ * if you need to know whether key exists.
+ *
  * Returns: whether list named with @key existed and contained @value.
  *
  * Since: 0.10
@@ -943,6 +942,20 @@ _structure_take_value_by_pspec (ClapperEnhancerProxy *self,
   return FALSE;
 }
 
+static void
+_trigger_reactable_configure_take (ClapperEnhancerProxy *self, GstStructure *structure)
+{
+  ClapperPlayer *player = clapper_player_get_from_ancestor (GST_OBJECT_CAST (self));
+
+  if (G_LIKELY (player != NULL)) {
+    clapper_reactables_manager_trigger_configure_take_config (
+        player->reactables_manager, self, structure);
+    gst_object_unref (player);
+  } else {
+    gst_structure_free (structure);
+  }
+}
+
 /**
  * clapper_enhancer_proxy_set_locally:
  * @proxy: a #ClapperEnhancerProxy
@@ -1013,10 +1026,10 @@ clapper_enhancer_proxy_set_locally (ClapperEnhancerProxy *self, const gchar *fir
 
   _update_local_config_from_structure (self, structure);
 
-  /* TODO: _post_local_config instead of free if managed
-   * (for when managed interfaces are implemented) */
-
-  gst_structure_free (structure);
+  if (clapper_enhancer_proxy_target_has_interface (self, CLAPPER_TYPE_REACTABLE))
+    _trigger_reactable_configure_take (self, structure);
+  else
+    gst_structure_free (structure);
 }
 
 /**
@@ -1080,10 +1093,62 @@ clapper_enhancer_proxy_set_locally_with_table (ClapperEnhancerProxy *self, GHash
 
   _update_local_config_from_structure (self, structure);
 
-  /* TODO: _post_local_config instead of free if managed
-   * (for when managed interfaces are implemented) */
+  if (clapper_enhancer_proxy_target_has_interface (self, CLAPPER_TYPE_REACTABLE))
+    _trigger_reactable_configure_take (self, structure);
+  else
+    gst_structure_free (structure);
+}
 
-  gst_structure_free (structure);
+/**
+ * clapper_enhancer_proxy_set_target_creation_allowed:
+ * @proxy: a #ClapperEnhancerProxy
+ * @allowed: whether allowed
+ *
+ * Set whether to allow instances of proxy target to be created.
+ *
+ * See [property@Clapper.EnhancerProxy:target-creation-allowed] for
+ * detailed descripton what this does.
+ *
+ * Since: 0.10
+ */
+void
+clapper_enhancer_proxy_set_target_creation_allowed (ClapperEnhancerProxy *self, gboolean allowed)
+{
+  gboolean changed;
+
+  g_return_if_fail (CLAPPER_IS_ENHANCER_PROXY (self));
+
+  GST_OBJECT_LOCK (self);
+  if ((changed = self->allowed != allowed))
+    self->allowed = allowed;
+  GST_OBJECT_UNLOCK (self);
+
+  if (changed)
+    g_object_notify_by_pspec (G_OBJECT (self), param_specs[PROP_TARGET_CREATION_ALLOWED]);
+}
+
+/**
+ * clapper_enhancer_proxy_get_target_creation_allowed:
+ * @proxy: a #ClapperEnhancerProxy
+ *
+ * Get whether it is allowed to create instances of enhancer that this proxy targets.
+ *
+ * Returns: whether target creation is allowed.
+ *
+ * Since: 0.10
+ */
+gboolean
+clapper_enhancer_proxy_get_target_creation_allowed (ClapperEnhancerProxy *self)
+{
+  gboolean allowed;
+
+  g_return_val_if_fail (CLAPPER_IS_ENHANCER_PROXY (self), FALSE);
+
+  GST_OBJECT_LOCK (self);
+  allowed = self->allowed;
+  GST_OBJECT_UNLOCK (self);
+
+  return allowed;
 }
 
 static void
@@ -1135,6 +1200,25 @@ clapper_enhancer_proxy_get_property (GObject *object, guint prop_id,
     case PROP_VERSION:
       g_value_set_string (value, clapper_enhancer_proxy_get_version (self));
       break;
+    case PROP_TARGET_CREATION_ALLOWED:
+      g_value_set_boolean (value, clapper_enhancer_proxy_get_target_creation_allowed (self));
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+clapper_enhancer_proxy_set_property (GObject *object, guint prop_id,
+    const GValue *value, GParamSpec *pspec)
+{
+  ClapperEnhancerProxy *self = CLAPPER_ENHANCER_PROXY_CAST (object);
+
+  switch (prop_id) {
+    case PROP_TARGET_CREATION_ALLOWED:
+      clapper_enhancer_proxy_set_target_creation_allowed (self, g_value_get_boolean (value));
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -1150,6 +1234,7 @@ clapper_enhancer_proxy_class_init (ClapperEnhancerProxyClass *klass)
       "Clapper Enhancer Proxy");
 
   gobject_class->get_property = clapper_enhancer_proxy_get_property;
+  gobject_class->set_property = clapper_enhancer_proxy_set_property;
   gobject_class->finalize = clapper_enhancer_proxy_finalize;
 
   /**
@@ -1207,5 +1292,29 @@ clapper_enhancer_proxy_class_init (ClapperEnhancerProxyClass *klass)
       NULL, NULL, NULL,
       G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
 
+  /**
+   * ClapperEnhancerProxy:target-creation-allowed:
+   *
+   * Whether to allow instances of proxy target to be created.
+   *
+   * This effectively means whether the given enhancer can be used.
+   *
+   * By default all enhancers that work on-demand such as [iface@Clapper.Extractable]
+   * are allowed while enhancers implementing [iface@Clapper.Reactable] are not.
+   *
+   * Value of this property from a `GLOBAL` [class@Clapper.EnhancerProxyList] will carry
+   * over to all newly created [class@Clapper.Player] objects, while altering this on
+   * `LOCAL` proxy list will only influence given player instance that list belongs to.
+   *
+   * Changing this property will not remove already created enhancer instances, thus
+   * it is usually best practice to allow/disallow creation of given enhancer plugin
+   * right after [class@Clapper.Player] is created (before it or its queue are used).
+   *
+   * Since: 0.10
+   */
+  param_specs[PROP_TARGET_CREATION_ALLOWED] = g_param_spec_boolean ("target-creation-allowed",
+      NULL, NULL, FALSE,
+      G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
   g_object_class_install_properties (gobject_class, PROP_LAST, param_specs);
 }

src/lib/clapper/clapper-enhancer-proxy.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once
@@ -77,4 +76,10 @@ void clapper_enhancer_proxy_set_locally (ClapperEnhancerProxy *proxy, const gcha
 CLAPPER_API
 void clapper_enhancer_proxy_set_locally_with_table (ClapperEnhancerProxy *proxy, GHashTable *table);
 
+CLAPPER_API
+void clapper_enhancer_proxy_set_target_creation_allowed (ClapperEnhancerProxy *proxy, gboolean allowed);
+
+CLAPPER_API
+gboolean clapper_enhancer_proxy_get_target_creation_allowed (ClapperEnhancerProxy *proxy);
+
 G_END_DECLS

src/lib/clapper/clapper-enhancers-loader-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-enhancers-loader.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "config.h"
@@ -33,6 +32,9 @@ static HMODULE _enhancers_dll_handle = NULL;
 
 // Supported interfaces
 #include "clapper-extractable.h"
+#include "clapper-reactable.h"
+
+#include <clapper-functionalities-availability.h>
 
 #define GST_CAT_DEFAULT clapper_enhancers_loader_debug
 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
@@ -52,6 +54,28 @@ _import_enhancers (const gchar *enhancers_path)
   g_strfreev (dir_paths);
 }
 
+static GObject *
+_force_create_enhancer (ClapperEnhancerProxy *proxy, GType iface_type)
+{
+  GObject *enhancer = NULL;
+  PeasPluginInfo *info = (PeasPluginInfo *) clapper_enhancer_proxy_get_peas_info (proxy);
+
+  g_mutex_lock (&load_lock);
+
+  if (!peas_plugin_info_is_loaded (info) && !peas_engine_load_plugin (_engine, info)) {
+    GST_ERROR ("Could not load enhancer: %s", peas_plugin_info_get_module_name (info));
+  } else if (!peas_engine_provides_extension (_engine, info, iface_type)) {
+    GST_LOG ("No \"%s\" enhancer in module: %s", g_type_name (iface_type),
+        peas_plugin_info_get_module_name (info));
+  } else {
+    enhancer = peas_engine_create_extension (_engine, info, iface_type, NULL);
+  }
+
+  g_mutex_unlock (&load_lock);
+
+  return enhancer;
+}
+
 /*
  * clapper_enhancers_loader_initialize:
  *
@@ -110,6 +134,36 @@ clapper_enhancers_loader_initialize (ClapperEnhancerProxyList *proxies)
     ClapperEnhancerProxy *proxy;
     gboolean filled;
 
+    /* FIXME: 1.0: Remove together with features code and manager.
+     * These would clash with each other, so avoid loading these
+     * as enhancers when also compiled as part of the library. */
+#if (CLAPPER_HAVE_MPRIS || CLAPPER_HAVE_DISCOVERER || CLAPPER_HAVE_SERVER)
+    guint f_index;
+    const gchar *module_name = peas_plugin_info_get_module_name (info);
+    const gchar *ported_features[] = {
+#if CLAPPER_HAVE_MPRIS
+      "clapper-mpris",
+#endif
+#if CLAPPER_HAVE_DISCOVERER
+      "clapper-discoverer",
+#endif
+#if CLAPPER_HAVE_SERVER
+      "clapper-server",
+#endif
+    };
+
+    for (f_index = 0; f_index < G_N_ELEMENTS (ported_features); ++f_index) {
+      if (strcmp (module_name, ported_features[f_index]) == 0) {
+        GST_INFO ("Skipped \"%s\" enhancer module, since its"
+          " loaded from deprecated feature object", module_name);
+        g_clear_object (&info);
+      }
+    }
+
+    if (!info) // cleared when exists as feature
+      continue;
+#endif
+
     /* Clapper supports only 1 proxy per plugin. Each plugin can
      * ship 1 class, but it can implement more than 1 interface. */
     proxy = clapper_enhancer_proxy_new_global_take ((GObject *) info);
@@ -118,12 +172,12 @@ clapper_enhancers_loader_initialize (ClapperEnhancerProxyList *proxies)
      * Otherwise make an instance and fill missing data from it (slow). */
     if (!(filled = clapper_enhancer_proxy_fill_from_cache (proxy))) {
       GObject *enhancer;
-      GType main_types[1] = { CLAPPER_TYPE_EXTRACTABLE };
+      const GType main_types[] = { CLAPPER_TYPE_EXTRACTABLE, CLAPPER_TYPE_REACTABLE };
       guint j;
 
       /* We cannot ask libpeas for "any" of our main interfaces, so try each one until found */
       for (j = 0; j < G_N_ELEMENTS (main_types); ++j) {
-        if ((enhancer = clapper_enhancers_loader_create_enhancer (proxy, main_types[j]))) {
+        if ((enhancer = _force_create_enhancer (proxy, main_types[j]))) {
           filled = clapper_enhancer_proxy_fill_from_instance (proxy, enhancer);
           g_object_unref (enhancer);
 
@@ -168,21 +222,8 @@ clapper_enhancers_loader_initialize (ClapperEnhancerProxyList *proxies)
 GObject *
 clapper_enhancers_loader_create_enhancer (ClapperEnhancerProxy *proxy, GType iface_type)
 {
-  GObject *enhancer = NULL;
-  PeasPluginInfo *info = (PeasPluginInfo *) clapper_enhancer_proxy_get_peas_info (proxy);
+  if (!clapper_enhancer_proxy_get_target_creation_allowed (proxy))
+    return NULL;
 
-  g_mutex_lock (&load_lock);
-
-  if (!peas_plugin_info_is_loaded (info) && !peas_engine_load_plugin (_engine, info)) {
-    GST_ERROR ("Could not load enhancer: %s", peas_plugin_info_get_module_name (info));
-  } else if (!peas_engine_provides_extension (_engine, info, iface_type)) {
-    GST_LOG ("No \"%s\" enhancer in module: %s", g_type_name (iface_type),
-        peas_plugin_info_get_module_name (info));
-  } else {
-    enhancer = peas_engine_create_extension (_engine, info, iface_type, NULL);
-  }
-
-  g_mutex_unlock (&load_lock);
-
-  return enhancer;
+  return _force_create_enhancer (proxy, iface_type);
 }

src/lib/clapper/clapper-enums-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-enums.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once
@@ -151,4 +150,23 @@ typedef enum
   CLAPPER_ENHANCER_PARAM_DIRPATH = 1 << 20,
 } ClapperEnhancerParamFlags;
 
+/**
+ * ClapperReactableItemUpdatedFlags:
+ * @CLAPPER_REACTABLE_ITEM_UPDATED_TITLE: Media item title was updated.
+ * @CLAPPER_REACTABLE_ITEM_UPDATED_DURATION: Media item duration was updated.
+ * @CLAPPER_REACTABLE_ITEM_UPDATED_TIMELINE: Media item timeline was updated.
+ * @CLAPPER_REACTABLE_ITEM_UPDATED_TAGS: Media item tags were updated.
+ *
+ * Flags informing which properties were updated within [class@Clapper.MediaItem].
+ *
+ * Since: 0.10
+ */
+typedef enum
+{
+  CLAPPER_REACTABLE_ITEM_UPDATED_TITLE = 1 << 0,
+  CLAPPER_REACTABLE_ITEM_UPDATED_DURATION = 1 << 1,
+  CLAPPER_REACTABLE_ITEM_UPDATED_TIMELINE = 1 << 2,
+  CLAPPER_REACTABLE_ITEM_UPDATED_TAGS = 1 << 3,
+} ClapperReactableItemUpdatedFlags;
+
 G_END_DECLS

src/lib/clapper/clapper-extractable-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-extractable.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper/clapper-extractable.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-feature-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-feature.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**
@@ -30,6 +29,8 @@
  * virtual functions logic, while for controlling playback implementation
  * may call [method@Gst.Object.get_parent] to acquire a weak reference on
  * a parent [class@Clapper.Player] object feature was added to.
+ *
+ * Deprecated: 0.10: Use [iface@Clapper.Reactable] instead.
  */
 
 #include "clapper-feature.h"

src/lib/clapper/clapper-feature.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once
@@ -37,7 +36,7 @@ G_BEGIN_DECLS
 #define CLAPPER_TYPE_FEATURE (clapper_feature_get_type())
 #define CLAPPER_FEATURE_CAST(obj) ((ClapperFeature *)(obj))
 
-CLAPPER_API
+CLAPPER_DEPRECATED_FOR(ClapperReactable)
 G_DECLARE_DERIVABLE_TYPE (ClapperFeature, clapper_feature, CLAPPER, FEATURE, GstObject)
 
 /**

src/lib/clapper/clapper-features-bus-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-features-bus.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "clapper-bus-private.h"

src/lib/clapper/clapper-features-manager-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-features-manager.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include "clapper-features-manager-private.h"

src/lib/clapper/clapper-functionalities-availability.h.in

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-harvest-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-harvest.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper/clapper-harvest.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-marker-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-marker.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**

src/lib/clapper/clapper-marker.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-media-item-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once
@@ -23,7 +22,7 @@
 #include <gst/pbutils/pbutils.h>
 
 #include "clapper-media-item.h"
-#include "clapper-player-private.h"
+#include "clapper-player.h"
 #include "clapper-app-bus-private.h"
 
 G_BEGIN_DECLS

src/lib/clapper/clapper-media-item.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**
@@ -30,6 +29,7 @@
 #include "clapper-timeline-private.h"
 #include "clapper-player-private.h"
 #include "clapper-playbin-bus-private.h"
+#include "clapper-reactables-manager-private.h"
 #include "clapper-features-manager-private.h"
 #include "clapper-utils-private.h"
 
@@ -43,6 +43,7 @@ struct _ClapperMediaItem
   gchar *uri;
   gchar *suburi;
 
+  GstTagList *tags;
   ClapperTimeline *timeline;
 
   guint id;
@@ -56,6 +57,13 @@ struct _ClapperMediaItem
   gboolean used;
 };
 
+typedef struct
+{
+  ClapperMediaItem *item;
+  gboolean changed;
+  gboolean from_user;
+} ClapperMediaItemTagIterData;
+
 enum
 {
   PROP_0,
@@ -63,6 +71,7 @@ enum
   PROP_URI,
   PROP_SUBURI,
   PROP_CACHE_LOCATION,
+  PROP_TAGS,
   PROP_TITLE,
   PROP_CONTAINER_FORMAT,
   PROP_DURATION,
@@ -111,8 +120,8 @@ clapper_media_item_new (const gchar *uri)
 
   /* FIXME: Set initial container format from file extension parsing */
 
-  GST_TRACE_OBJECT (item, "New media item, ID: %u, URI: %s, title: %s",
-      item->id, item->uri, item->title);
+  GST_TRACE_OBJECT (item, "New media item, ID: %u, URI: \"%s\", title: \"%s\"",
+      item->id, item->uri, GST_STR_NULL (item->title));
 
   return item;
 }
@@ -258,27 +267,6 @@ clapper_media_item_get_suburi (ClapperMediaItem *self)
   return suburi;
 }
 
-static gboolean
-clapper_media_item_take_title (ClapperMediaItem *self, gchar *title,
-    ClapperAppBus *app_bus)
-{
-  gboolean changed;
-
-  GST_OBJECT_LOCK (self);
-  if ((changed = g_strcmp0 (self->title, title) != 0)) {
-    g_free (self->title);
-    self->title = title;
-  }
-  GST_OBJECT_UNLOCK (self);
-
-  if (changed)
-    clapper_app_bus_post_prop_notify (app_bus, GST_OBJECT_CAST (self), param_specs[PROP_TITLE]);
-  else
-    g_free (title);
-
-  return changed;
-}
-
 /**
  * clapper_media_item_get_title:
  * @item: a #ClapperMediaItem
@@ -305,25 +293,24 @@ clapper_media_item_get_title (ClapperMediaItem *self)
   return title;
 }
 
-static gboolean
-clapper_media_item_take_container_format (ClapperMediaItem *self, gchar *container_format,
-    ClapperAppBus *app_bus)
+static inline gboolean
+_refresh_tag_prop_unlocked (ClapperMediaItem *self, const gchar *tag,
+    gboolean from_user, gchar **tag_ptr)
 {
-  gboolean changed;
+  const gchar *string;
 
-  GST_OBJECT_LOCK (self);
-  if ((changed = g_strcmp0 (self->container_format, container_format) != 0)) {
-    g_free (self->container_format);
-    self->container_format = container_format;
-  }
-  GST_OBJECT_UNLOCK (self);
+  if ((*tag_ptr && from_user) // if already set, user cannot modify it
+      || !gst_tag_list_peek_string_index (self->tags, tag, 0, &string) // guarantees non-empty string
+      || (g_strcmp0 (*tag_ptr, string) == 0))
+    return FALSE;
 
-  if (changed)
-    clapper_app_bus_post_prop_notify (app_bus, GST_OBJECT_CAST (self), param_specs[PROP_CONTAINER_FORMAT]);
-  else
-    g_free (container_format);
+  GST_LOG_OBJECT (self, "Tag prop \"%s\" update: \"%s\" -> \"%s\"",
+      tag, GST_STR_NULL (*tag_ptr), string);
 
-  return changed;
+  g_free (*tag_ptr);
+  *tag_ptr = g_strdup (string);
+
+  return TRUE;
 }
 
 /**
@@ -333,6 +320,8 @@ clapper_media_item_take_container_format (ClapperMediaItem *self, gchar *contain
  * Get media item container format.
  *
  * Returns: (transfer full) (nullable): media container format.
+ *
+ * Deprecated: 0.10: Get `container-format` from [property@Clapper.MediaItem:tags] instead.
  */
 gchar *
 clapper_media_item_get_container_format (ClapperMediaItem *self)
@@ -389,11 +378,214 @@ clapper_media_item_get_duration (ClapperMediaItem *self)
   return duration;
 }
 
+/**
+ * clapper_media_item_get_tags:
+ * @item: a #ClapperMediaItem
+ *
+ * Get readable list of tags stored in media item.
+ *
+ * Returns: (transfer full): a #GstTagList.
+ *
+ * Since: 0.10
+ */
+GstTagList *
+clapper_media_item_get_tags (ClapperMediaItem *self)
+{
+  GstTagList *tags = NULL;
+
+  g_return_val_if_fail (CLAPPER_IS_MEDIA_ITEM (self), NULL);
+
+  GST_OBJECT_LOCK (self);
+  tags = gst_tag_list_ref (self->tags);
+  GST_OBJECT_UNLOCK (self);
+
+  return tags;
+}
+
+static void
+_tags_replace_func (const GstTagList *tags, const gchar *tag, ClapperMediaItemTagIterData *data)
+{
+  ClapperMediaItem *self = data->item;
+  guint index = 0;
+  gboolean replace = FALSE;
+
+  while (TRUE) {
+    const GValue *old_value = gst_tag_list_get_value_index (self->tags, tag, index);
+    const GValue *new_value = gst_tag_list_get_value_index (tags, tag, index);
+
+    /* Number of old values is the same or greater and
+     * all values until this iteration were the same */
+    if (!new_value)
+      break;
+
+    /* A wild new tag appeared */
+    if (!old_value) {
+      replace = TRUE;
+      break;
+    }
+
+    /* Users can only set non-existing tags */
+    if (data->from_user)
+      break;
+
+    /* Check with tolerance for doubles */
+    if (G_VALUE_TYPE (old_value) == G_TYPE_DOUBLE
+        && G_VALUE_TYPE (new_value) == G_TYPE_DOUBLE) {
+      gdouble old_dbl, new_dbl;
+
+      old_dbl = g_value_get_double (old_value);
+      new_dbl = g_value_get_double (new_value);
+
+      if ((replace = !G_APPROX_VALUE (old_dbl, new_dbl, FLT_EPSILON)))
+        break;
+    } else if (gst_value_compare (old_value, new_value) != GST_VALUE_EQUAL) {
+      replace = TRUE;
+      break;
+    }
+
+    ++index;
+  }
+
+  if (replace) {
+    const GValue *value;
+    index = 0;
+
+    GST_LOG_OBJECT (self, "Replacing \"%s\" tag value", tag);
+
+    /* Ensure writable, but only when replacing something */
+    if (!data->changed) {
+      self->tags = gst_tag_list_make_writable (self->tags);
+      data->changed = TRUE;
+    }
+
+    /* Replace first tag value (so it becomes sole member) */
+    value = gst_tag_list_get_value_index (tags, tag, index);
+    gst_tag_list_add_value (self->tags, GST_TAG_MERGE_REPLACE, tag, value);
+
+    /* Append any remaining tags (so next time we iterate indexes will match) */
+    while ((value = gst_tag_list_get_value_index (tags, tag, ++index)))
+      gst_tag_list_add_value (self->tags, GST_TAG_MERGE_APPEND, tag, value);
+  }
+}
+
+static gboolean
+clapper_media_item_insert_tags_internal (ClapperMediaItem *self, const GstTagList *tags,
+    ClapperAppBus *app_bus, gboolean from_user, ClapperReactableItemUpdatedFlags *flags)
+{
+  ClapperMediaItemTagIterData data;
+  gboolean title_changed = FALSE, cont_changed = FALSE;
+
+  GST_OBJECT_LOCK (self);
+
+  data.item = self;
+  data.changed = FALSE;
+  data.from_user = from_user;
+
+  if (G_LIKELY (tags != self->tags))
+    gst_tag_list_foreach (tags, (GstTagForeachFunc) _tags_replace_func, &data);
+
+  if (data.changed) {
+    *flags |= CLAPPER_REACTABLE_ITEM_UPDATED_TAGS;
+
+    if ((title_changed = _refresh_tag_prop_unlocked (self, GST_TAG_TITLE,
+        from_user, &self->title))) {
+      *flags |= CLAPPER_REACTABLE_ITEM_UPDATED_TITLE;
+    }
+    cont_changed = _refresh_tag_prop_unlocked (self, GST_TAG_CONTAINER_FORMAT,
+        from_user, &self->container_format);
+  }
+
+  GST_OBJECT_UNLOCK (self);
+
+  if (!data.changed)
+    return FALSE;
+
+  if (app_bus) {
+    GstObject *src = GST_OBJECT_CAST (self);
+
+    clapper_app_bus_post_prop_notify (app_bus, src, param_specs[PROP_TAGS]);
+
+    if (title_changed)
+      clapper_app_bus_post_prop_notify (app_bus, src, param_specs[PROP_TITLE]);
+    if (cont_changed)
+      clapper_app_bus_post_prop_notify (app_bus, src, param_specs[PROP_CONTAINER_FORMAT]);
+  } else {
+    GObject *src = G_OBJECT (self);
+
+    clapper_utils_prop_notify_on_main_sync (src, param_specs[PROP_TAGS]);
+
+    if (title_changed)
+      clapper_utils_prop_notify_on_main_sync (src, param_specs[PROP_TITLE]);
+    if (cont_changed)
+      clapper_utils_prop_notify_on_main_sync (src, param_specs[PROP_CONTAINER_FORMAT]);
+  }
+
+  return TRUE;
+}
+
+/**
+ * clapper_media_item_populate_tags:
+ * @item: a #ClapperMediaItem
+ * @tags: a #GstTagList of GLOBAL scope
+ *
+ * Populate non-existing tags in @item tag list.
+ *
+ * Passed @tags must use [enum@Gst.TagScope.GLOBAL] scope.
+ *
+ * Note that tags are automatically determined during media playback
+ * and those take precedence. This function can be useful if an app can
+ * determine some tags that are not in media metadata or for filling
+ * item with some initial/cached tags to display in UI before playback.
+ *
+ * When a tag already exists in the tag list (was populated) this
+ * function will not overwrite it. If you really need to permanently
+ * override some tags in media, you can use `taginject` element as
+ * player video/audio filter instead.
+ *
+ * Returns: whether at least one tag got updated.
+ *
+ * Since: 0.10
+ */
+gboolean
+clapper_media_item_populate_tags (ClapperMediaItem *self, const GstTagList *tags)
+{
+  ClapperPlayer *player;
+  ClapperAppBus *app_bus = NULL;
+  ClapperReactableItemUpdatedFlags flags = 0;
+  gboolean changed;
+
+  g_return_val_if_fail (CLAPPER_IS_MEDIA_ITEM (self), FALSE);
+  g_return_val_if_fail (tags != NULL, FALSE);
+
+  if (G_UNLIKELY (gst_tag_list_get_scope (tags) != GST_TAG_SCOPE_GLOBAL)) {
+    g_warning ("Cannot populate media item tags using a list with non-global tag scope");
+    return FALSE;
+  }
+
+  if ((player = clapper_player_get_from_ancestor (GST_OBJECT_CAST (self))))
+    app_bus = player->app_bus;
+
+  changed = clapper_media_item_insert_tags_internal (self, tags, app_bus, TRUE, &flags);
+
+  if (changed && player) {
+    ClapperFeaturesManager *features_manager;
+
+    if (player->reactables_manager)
+      clapper_reactables_manager_trigger_item_updated (player->reactables_manager, self, flags);
+    if ((features_manager = clapper_player_get_features_manager (player)))
+      clapper_features_manager_trigger_item_updated (features_manager, self);
+  }
+
+  gst_clear_object (&player);
+
+  return changed;
+}
+
 /**
  * clapper_media_item_get_timeline:
  * @item: a #ClapperMediaItem
  *
- * Get the [class@Clapper.Timeline] assosiated with @item.
+ * Get the [class@Clapper.Timeline] associated with @item.
  *
  * Returns: (transfer none): a #ClapperTimeline of item.
  */
@@ -405,21 +597,6 @@ clapper_media_item_get_timeline (ClapperMediaItem *self)
   return self->timeline;
 }
 
-static gboolean
-clapper_media_item_update_from_container_tags (ClapperMediaItem *self, const GstTagList *tags,
-    ClapperAppBus *app_bus)
-{
-  gchar *string = NULL;
-  gboolean changed = FALSE;
-
-  if (gst_tag_list_get_string (tags, GST_TAG_CONTAINER_FORMAT, &string))
-    changed |= clapper_media_item_take_container_format (self, string, app_bus);
-  if (gst_tag_list_get_string (tags, GST_TAG_TITLE, &string))
-    changed |= clapper_media_item_take_title (self, string, app_bus);
-
-  return changed;
-}
-
 void
 clapper_media_item_update_from_tag_list (ClapperMediaItem *self, const GstTagList *tags,
     ClapperPlayer *player)
@@ -427,11 +604,14 @@ clapper_media_item_update_from_tag_list (ClapperMediaItem *self, const GstTagLis
   GstTagScope scope = gst_tag_list_get_scope (tags);
 
   if (scope == GST_TAG_SCOPE_GLOBAL) {
-    gboolean changed = clapper_media_item_update_from_container_tags (self, tags, player->app_bus);
+    ClapperReactableItemUpdatedFlags flags = 0;
+    gboolean changed = clapper_media_item_insert_tags_internal (self, tags, player->app_bus, FALSE, &flags);
 
     if (changed) {
       ClapperFeaturesManager *features_manager;
 
+      if (player->reactables_manager)
+        clapper_reactables_manager_trigger_item_updated (player->reactables_manager, self, flags);
       if ((features_manager = clapper_player_get_features_manager (player)))
         clapper_features_manager_trigger_item_updated (features_manager, self);
     }
@@ -444,6 +624,7 @@ clapper_media_item_update_from_discoverer_info (ClapperMediaItem *self, GstDisco
   ClapperPlayer *player;
   GstDiscovererStreamInfo *sinfo;
   GstClockTime duration;
+  ClapperReactableItemUpdatedFlags flags = 0;
   gdouble val_dbl;
   gboolean changed = FALSE;
 
@@ -459,7 +640,7 @@ clapper_media_item_update_from_discoverer_info (ClapperMediaItem *self, GstDisco
       GstDiscovererContainerInfo *cinfo = (GstDiscovererContainerInfo *) sinfo;
 
       if ((tags = gst_discoverer_container_info_get_tags (cinfo)))
-        changed |= clapper_media_item_update_from_container_tags (self, tags, player->app_bus);
+        changed |= clapper_media_item_insert_tags_internal (self, tags, player->app_bus, FALSE, &flags);
     }
     gst_discoverer_stream_info_unref (sinfo);
   }
@@ -470,11 +651,16 @@ clapper_media_item_update_from_discoverer_info (ClapperMediaItem *self, GstDisco
     duration = 0;
 
   val_dbl = (gdouble) duration / GST_SECOND;
-  changed |= clapper_media_item_set_duration (self, val_dbl, player->app_bus);
+  if (clapper_media_item_set_duration (self, val_dbl, player->app_bus)) {
+    changed = TRUE;
+    flags |= CLAPPER_REACTABLE_ITEM_UPDATED_DURATION;
+  }
 
   if (changed) {
     ClapperFeaturesManager *features_manager;
 
+    if (player->reactables_manager)
+      clapper_reactables_manager_trigger_item_updated (player->reactables_manager, self, flags);
     if ((features_manager = clapper_player_get_features_manager (player)))
       clapper_features_manager_trigger_item_updated (features_manager, self);
   }
@@ -542,6 +728,9 @@ clapper_media_item_get_used (ClapperMediaItem *self)
 static void
 clapper_media_item_init (ClapperMediaItem *self)
 {
+  self->tags = gst_tag_list_new_empty ();
+  gst_tag_list_set_scope (self->tags, GST_TAG_SCOPE_GLOBAL);
+
   self->timeline = clapper_timeline_new ();
   gst_object_set_parent (GST_OBJECT_CAST (self->timeline), GST_OBJECT_CAST (self));
 }
@@ -571,6 +760,8 @@ clapper_media_item_finalize (GObject *object)
   g_free (self->title);
   g_free (self->container_format);
 
+  gst_tag_list_unref (self->tags);
+
   gst_object_unparent (GST_OBJECT_CAST (self->timeline));
   gst_object_unref (self->timeline);
 
@@ -617,6 +808,9 @@ clapper_media_item_get_property (GObject *object, guint prop_id,
     case PROP_SUBURI:
       g_value_take_string (value, clapper_media_item_get_suburi (self));
       break;
+    case PROP_TAGS:
+      g_value_take_boxed (value, clapper_media_item_get_tags (self));
+      break;
     case PROP_TITLE:
       g_value_take_string (value, clapper_media_item_get_title (self));
       break;
@@ -686,10 +880,27 @@ clapper_media_item_class_init (ClapperMediaItemClass *klass)
       NULL, NULL, NULL,
       G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
 
+  /**
+   * ClapperMediaItem:tags:
+   *
+   * A readable list of tags stored in media item.
+   *
+   * Since: 0.10
+   */
+  param_specs[PROP_TAGS] = g_param_spec_boxed ("tags",
+      NULL, NULL, GST_TYPE_TAG_LIST,
+      G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+  /* FIXME: 1.0: Consider rename to e.g. "(menu/display)-title"
+   * and also make it non-nullable (return URI as final fallback) */
   /**
    * ClapperMediaItem:title:
    *
    * Media title.
+   *
+   * This might be a different string compared to `title` from
+   * [property@Clapper.MediaItem:tags], as this gives parsed
+   * title from file name/URI as fallback when no `title` tag.
    */
   param_specs[PROP_TITLE] = g_param_spec_string ("title",
       NULL, NULL, NULL,
@@ -699,15 +910,21 @@ clapper_media_item_class_init (ClapperMediaItemClass *klass)
    * ClapperMediaItem:container-format:
    *
    * Media container format.
+   *
+   * Deprecated: 0.10: Get `container-format` from [property@Clapper.MediaItem:tags] instead.
    */
   param_specs[PROP_CONTAINER_FORMAT] = g_param_spec_string ("container-format",
       NULL, NULL, NULL,
-      G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+      G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS | G_PARAM_DEPRECATED);
 
   /**
    * ClapperMediaItem:duration:
    *
    * Media duration as a decimal number in seconds.
+   *
+   * This might be a different value compared to `duration` from
+   * [property@Clapper.MediaItem:tags], as this value is updated
+   * during decoding instead of being a fixed value from metadata.
    */
   param_specs[PROP_DURATION] = g_param_spec_double ("duration",
       NULL, NULL, 0, G_MAXDOUBLE, 0,

src/lib/clapper/clapper-media-item.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once
@@ -27,6 +26,7 @@
 #include <glib-object.h>
 #include <gio/gio.h>
 #include <gst/gst.h>
+#include <gst/tag/tag.h>
 
 #include <clapper/clapper-visibility.h>
 #include <clapper/clapper-timeline.h>
@@ -63,12 +63,18 @@ gchar * clapper_media_item_get_suburi (ClapperMediaItem *item);
 CLAPPER_API
 gchar * clapper_media_item_get_title (ClapperMediaItem *item);
 
-CLAPPER_API
+CLAPPER_DEPRECATED_FOR(clapper_media_item_get_tags)
 gchar * clapper_media_item_get_container_format (ClapperMediaItem *item);
 
 CLAPPER_API
 gdouble clapper_media_item_get_duration (ClapperMediaItem *item);
 
+CLAPPER_API
+GstTagList * clapper_media_item_get_tags (ClapperMediaItem *item);
+
+CLAPPER_API
+gboolean clapper_media_item_populate_tags (ClapperMediaItem *item, const GstTagList *tags);
+
 CLAPPER_API
 ClapperTimeline * clapper_media_item_get_timeline (ClapperMediaItem *item);
 

src/lib/clapper/clapper-playbin-bus-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-playbin-bus.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #include <gst/pbutils/pbutils.h>
@@ -173,6 +172,10 @@ _update_current_duration (ClapperPlayer *player)
     if (clapper_media_item_set_duration (player->played_item, duration_dbl, player->app_bus)) {
       ClapperFeaturesManager *features_manager;
 
+      if (player->reactables_manager) {
+        clapper_reactables_manager_trigger_item_updated (player->reactables_manager, player->played_item,
+            CLAPPER_REACTABLE_ITEM_UPDATED_DURATION);
+      }
       if ((features_manager = clapper_player_get_features_manager (player)))
         clapper_features_manager_trigger_item_updated (features_manager, player->played_item);
     }
@@ -1046,6 +1049,8 @@ _handle_stream_start_msg (GstMessage *msg, ClapperPlayer *player)
   if (G_LIKELY (changed)) {
     clapper_queue_handle_played_item_changed (player->queue, player->played_item, player->app_bus);
 
+    if (player->reactables_manager)
+      clapper_reactables_manager_trigger_played_item_changed (player->reactables_manager, player->played_item);
     if (clapper_player_get_have_features (player))
       clapper_features_manager_trigger_played_item_changed (player->features_manager, player->played_item);
   }

src/lib/clapper/clapper-player-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once
@@ -27,6 +26,7 @@
 
 #include "clapper-app-bus-private.h"
 #include "clapper-features-manager-private.h"
+#include "clapper-reactables-manager-private.h"
 
 G_BEGIN_DECLS
 
@@ -47,6 +47,8 @@ struct _ClapperPlayer
   ClapperFeaturesManager *features_manager;
   gint have_features; // atomic integer
 
+  ClapperReactablesManager *reactables_manager;
+
   ClapperEnhancerProxyList *enhancer_proxies;
 
   /* This is different from queue current item as it is used/changed only

src/lib/clapper/clapper-player.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**
@@ -50,6 +49,7 @@
 #include "clapper-audio-stream-private.h"
 #include "clapper-subtitle-stream-private.h"
 #include "clapper-enhancer-proxy-list-private.h"
+#include "clapper-reactable.h"
 #include "clapper-enums-private.h"
 #include "clapper-utils-private.h"
 #include "../shared/clapper-shared-utils-private.h"
@@ -159,6 +159,8 @@ clapper_player_refresh_position (ClapperPlayer *self)
 
     clapper_app_bus_post_prop_notify (self->app_bus,
         GST_OBJECT_CAST (self), param_specs[PROP_POSITION]);
+    if (self->reactables_manager)
+      clapper_reactables_manager_trigger_position_changed (self->reactables_manager, position_dbl);
     if (clapper_player_get_have_features (self))
       clapper_features_manager_trigger_position_changed (self->features_manager, position_dbl);
   }
@@ -225,6 +227,8 @@ clapper_player_handle_playbin_state_changed (ClapperPlayer *self)
 
     clapper_app_bus_post_prop_notify (self->app_bus,
         GST_OBJECT_CAST (self), param_specs[PROP_STATE]);
+    if (self->reactables_manager)
+      clapper_reactables_manager_trigger_state_changed (self->reactables_manager, state);
     if (clapper_player_get_have_features (self))
       clapper_features_manager_trigger_state_changed (self->features_manager, state);
   }
@@ -256,6 +260,8 @@ clapper_player_handle_playbin_volume_changed (ClapperPlayer *self, const GValue
 
     clapper_app_bus_post_prop_notify (self->app_bus,
         GST_OBJECT_CAST (self), param_specs[PROP_VOLUME]);
+    if (self->reactables_manager)
+      clapper_reactables_manager_trigger_volume_changed (self->reactables_manager, volume);
     if (clapper_player_get_have_features (self))
       clapper_features_manager_trigger_volume_changed (self->features_manager, volume);
   }
@@ -280,6 +286,8 @@ clapper_player_handle_playbin_mute_changed (ClapperPlayer *self, const GValue *v
 
     clapper_app_bus_post_prop_notify (self->app_bus,
         GST_OBJECT_CAST (self), param_specs[PROP_MUTE]);
+    if (self->reactables_manager)
+      clapper_reactables_manager_trigger_mute_changed (self->reactables_manager, mute);
     if (clapper_player_get_have_features (self))
       clapper_features_manager_trigger_mute_changed (self->features_manager, mute);
   }
@@ -400,6 +408,8 @@ clapper_player_handle_playbin_rate_changed (ClapperPlayer *self, gdouble speed)
 
     clapper_app_bus_post_prop_notify (self->app_bus,
         GST_OBJECT_CAST (self), param_specs[PROP_SPEED]);
+    if (self->reactables_manager)
+      clapper_reactables_manager_trigger_speed_changed (self->reactables_manager, speed);
     if (clapper_player_get_have_features (self))
       clapper_features_manager_trigger_speed_changed (self->features_manager, speed);
   }
@@ -2326,6 +2336,11 @@ clapper_player_init (ClapperPlayer *self)
 
   clapper_enhancer_proxy_list_fill_from_global_proxies (self->enhancer_proxies);
 
+  if (clapper_enhancer_proxy_list_has_proxy_with_interface (self->enhancer_proxies, CLAPPER_TYPE_REACTABLE)) {
+    self->reactables_manager = clapper_reactables_manager_new ();
+    gst_object_set_parent (GST_OBJECT_CAST (self->reactables_manager), GST_OBJECT_CAST (self));
+  }
+
   self->position_query = gst_query_new_position (GST_FORMAT_TIME);
 
   self->current_state = GST_STATE_NULL;
@@ -2392,6 +2407,11 @@ clapper_player_finalize (GObject *object)
   gst_object_unparent (GST_OBJECT_CAST (self->subtitle_streams));
   gst_object_unref (self->subtitle_streams);
 
+  if (self->reactables_manager) {
+    gst_object_unparent (GST_OBJECT_CAST (self->reactables_manager));
+    gst_object_unref (self->reactables_manager);
+  }
+
   gst_object_unparent (GST_OBJECT_CAST (self->enhancer_proxies));
   gst_object_unref (self->enhancer_proxies);
 
@@ -2833,7 +2853,7 @@ clapper_player_class_init (ClapperPlayerClass *klass)
    * An initial bitrate (bits/s) to select during
    * starting adaptive streaming such as DASH or HLS.
    *
-   * If value is higher than lowest available bitrate in streaming
+   * If value is lower than the lowest available bitrate in streaming
    * manifest, then lowest possible bitrate will be selected.
    *
    * Since: 0.8

src/lib/clapper/clapper-player.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-queue-private.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-queue.c

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 /**
@@ -29,6 +28,8 @@
 #include "clapper-media-item-private.h"
 #include "clapper-player-private.h"
 #include "clapper-playbin-bus-private.h"
+#include "clapper-reactables-manager-private.h"
+#include "clapper-features-manager-private.h"
 
 #define CLAPPER_QUEUE_GET_REC_LOCK(obj) (&CLAPPER_QUEUE_CAST(obj)->rec_lock)
 #define CLAPPER_QUEUE_REC_LOCK(obj) g_rec_mutex_lock (CLAPPER_QUEUE_GET_REC_LOCK(obj))
@@ -132,15 +133,27 @@ _announce_model_update (ClapperQueue *self, guint index, guint removed, guint ad
   if (removed != added) {
     ClapperPlayer *player = clapper_player_get_from_ancestor (GST_OBJECT_CAST (self));
 
-    if (player && clapper_player_get_have_features (player)) {
-      if (added == 1) // addition
-        clapper_features_manager_trigger_queue_item_added (player->features_manager, changed_item, index);
-      else if (removed == 1) // removal
-        clapper_features_manager_trigger_queue_item_removed (player->features_manager, changed_item, index);
-      else if (removed > 1 && added == 0) // queue cleared
-        clapper_features_manager_trigger_queue_cleared (player->features_manager);
-      else
+    if (player) {
+      gboolean have_features = clapper_player_get_have_features (player);
+
+      if (added == 1) { // addition
+        if (player->reactables_manager)
+          clapper_reactables_manager_trigger_queue_item_added (player->reactables_manager, changed_item, index);
+        if (have_features)
+          clapper_features_manager_trigger_queue_item_added (player->features_manager, changed_item, index);
+      } else if (removed == 1) { // removal
+        if (player->reactables_manager)
+          clapper_reactables_manager_trigger_queue_item_removed (player->reactables_manager, changed_item, index);
+        if (have_features)
+          clapper_features_manager_trigger_queue_item_removed (player->features_manager, changed_item, index);
+      } else if (removed > 1 && added == 0) { // queue cleared
+        if (player->reactables_manager)
+          clapper_reactables_manager_trigger_queue_cleared (player->reactables_manager);
+        if (have_features)
+          clapper_features_manager_trigger_queue_cleared (player->features_manager);
+      } else {
         g_assert_not_reached ();
+      }
     }
 
     gst_clear_object (&player);
@@ -160,6 +173,8 @@ _announce_reposition (ClapperQueue *self, guint before, guint after)
   GST_DEBUG_OBJECT (self, "Announcing item reposition: %u -> %u", before, after);
 
   if ((player = clapper_player_get_from_ancestor (GST_OBJECT_CAST (self)))) {
+    if (player->reactables_manager)
+      clapper_reactables_manager_trigger_queue_item_repositioned (player->reactables_manager, before, after);
     if (clapper_player_get_have_features (player))
       clapper_features_manager_trigger_queue_item_repositioned (player->features_manager, before, after);
 
@@ -989,6 +1004,8 @@ clapper_queue_set_progression_mode (ClapperQueue *self, ClapperQueueProgressionM
 
     clapper_app_bus_post_prop_notify (player->app_bus,
         GST_OBJECT_CAST (self), param_specs[PROP_PROGRESSION_MODE]);
+    if (player->reactables_manager)
+      clapper_reactables_manager_trigger_queue_progression_changed (player->reactables_manager, mode);
     if (clapper_player_get_have_features (player))
       clapper_features_manager_trigger_queue_progression_changed (player->features_manager, mode);
 

src/lib/clapper/clapper-queue.h

@@ -12,9 +12,8 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
  */
 
 #pragma once

src/lib/clapper/clapper-reactable.c

@@ -0,0 +1,208 @@
+/* Clapper Playback Library
+ * Copyright (C) 2025 Rafał Dzięgiel <rafostar.github@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
+ */
+
+/**
+ * ClapperReactable:
+ *
+ * An interface for creating enhancers that react to the
+ * playback and/or events that should influence it.
+ *
+ * Since: 0.10
+ */
+
+#include "clapper-reactable.h"
+#include "clapper-utils-private.h"
+
+#define CLAPPER_REACTABLE_DO_WITH_QUEUE(reactable, _queue_dst, ...) {  \
+    ClapperPlayer *_player = clapper_reactable_get_player (reactable); \
+    if (G_LIKELY (_player != NULL)) {                                  \
+      *_queue_dst = clapper_player_get_queue (_player);                \
+      __VA_ARGS__                                                      \
+      gst_object_unref (_player); }}
+
+G_DEFINE_INTERFACE (ClapperReactable, clapper_reactable, GST_TYPE_OBJECT);
+
+static void
+clapper_reactable_default_init (ClapperReactableInterface *iface)
+{
+}
+
+/**
+ * clapper_reactable_get_player:
+ * @reactable: a #ClapperReactable
+ *
+ * Get the [class@Clapper.Player] that this reactable is reacting to.
+ *
+ * This is meant to be used in implementations where reaction goes the
+ * other way around (from enhancer plugin to the player). For example
+ * some external event needs to influence parent player object like
+ * changing its state, seeking, etc.
+ *
+ * Note that enhancers are working in a non-main application thread, thus
+ * if you need to do operations on a [class@Clapper.Queue] such as adding/removing
+ * items, you need to switch thread first. Otherwise this will not be thread safe
+ * for applications that use single threaded toolkits such as #GTK. You can do this
+ * manually or use provided reactable convenience functions.
+ *
+ * Due to the threaded nature, you should also avoid comparisons to the current
+ * properties values in the player or its queue. While these are thread safe, there
+ * is no guarantee that values/objects between threads are still the same in both
+ * (or still exist). For example, instead of using [property@Clapper.Queue:current_item],
+ * monitor it with implemented [vfunc@Clapper.Reactable.played_item_changed] instead,
+ * as these functions are all serialized into your implementation thread.
+ *
+ * Returns: (transfer full) (nullable): A reference to the parent #ClapperPlayer.
+ *
+ * Since: 0.10
+ */
+ClapperPlayer *
+clapper_reactable_get_player (ClapperReactable *self)
+{
+  g_return_val_if_fail (CLAPPER_IS_REACTABLE (self), NULL);
+
+  return CLAPPER_PLAYER_CAST (gst_object_get_parent (GST_OBJECT_CAST (self)));
+}
+
+/**
+ * clapper_reactable_queue_append_sync:
+ * @reactable: a #ClapperReactable
+ * @item: a #ClapperMediaItem
+ *
+ * A convenience function that within application main thread synchronously appends
+ * an @item to the playback queue of the player that @reactable belongs to.
+ *
+ * Reactable enhancers should only modify the queue from the application
+ * main thread, switching thread either themselves or using this convenience
+ * function that does so.
+ *
+ * Note that this function will do no operation if called when there is no player
+ * set yet (e.g. inside enhancer construction) or if enhancer outlived the parent
+ * instance somehow. Both cases are considered to be implementation bug.
+ *
+ * Since: 0.10
+ */
+void
+clapper_reactable_queue_append_sync (ClapperReactable *self, ClapperMediaItem *item)
+{
+  ClapperQueue *queue;
+
+  g_return_if_fail (CLAPPER_IS_REACTABLE (self));
+  g_return_if_fail (CLAPPER_IS_MEDIA_ITEM (item));
+
+  CLAPPER_REACTABLE_DO_WITH_QUEUE (self, &queue, {
+    clapper_utils_queue_append_on_main_sync (queue, item);
+  });
+}
+
+/**
+ * clapper_reactable_queue_insert_sync:
+ * @reactable: a #ClapperReactable
+ * @item: a #ClapperMediaItem
+ * @after_item: a #ClapperMediaItem after which to insert or %NULL to prepend
+ *
+ * A convenience function that within application main thread synchronously inserts
+ * an @item to the playback queue position after @after_item of the player that
+ * @reactable belongs to.
+ *
+ * This function uses @after_item instead of position index in order to ensure
+ * desired position does not change during thread switching.
+ *
+ * Reactable enhancers should only modify the queue from the application
+ * main thread, switching thread either themselves or using this convenience
+ * function that does so.
+ *
+ * Note that this function will do no operation if called when there is no player
+ * set yet (e.g. inside enhancer construction) or if enhancer outlived the parent
+ * instance somehow. Both cases are considered to be implementation bug.
+ *
+ * Since: 0.10
+ */
+void
+clapper_reactable_queue_insert_sync (ClapperReactable *self,
+    ClapperMediaItem *item, ClapperMediaItem *after_item)
+{
+  ClapperQueue *queue;
+
+  g_return_if_fail (CLAPPER_IS_REACTABLE (self));
+  g_return_if_fail (CLAPPER_IS_MEDIA_ITEM (item));
+  g_return_if_fail (after_item == NULL || CLAPPER_IS_MEDIA_ITEM (after_item));
+
+  CLAPPER_REACTABLE_DO_WITH_QUEUE (self, &queue, {
+    clapper_utils_queue_insert_on_main_sync (queue, item, after_item);
+  });
+}
+
+/**
+ * clapper_reactable_queue_remove_sync:
+ * @reactable: a #ClapperReactable
+ * @item: a #ClapperMediaItem
+ *
+ * A convenience function that within application main thread synchronously removes
+ * an @item from the playback queue of the player that @reactable belongs to.
+ *
+ * Reactable enhancers should only modify the queue from the application
+ * main thread, switching thread either themselves or using this convenience
+ * function that does so.
+ *
+ * Note that this function will do no operation if called when there is no player
+ * set yet (e.g. inside enhancer construction) or if enhancer outlived the parent
+ * instance somehow. Both cases are considered to be implementation bug.
+ *
+ * Since: 0.10
+ */
+void
+clapper_reactable_queue_remove_sync (ClapperReactable *self, ClapperMediaItem *item)
+{
+  ClapperQueue *queue;
+
+  g_return_if_fail (CLAPPER_IS_REACTABLE (self));
+  g_return_if_fail (CLAPPER_IS_MEDIA_ITEM (item));
+
+  CLAPPER_REACTABLE_DO_WITH_QUEUE (self, &queue, {
+    clapper_utils_queue_remove_on_main_sync (queue, item);
+  });
+}
+
+/**
+ * clapper_reactable_queue_clear_sync:
+ * @reactable: a #ClapperReactable
+ *
+ * A convenience function that within application main thread synchronously clears
+ * the playback queue of the player that @reactable belongs to.
+ *
+ * Reactable enhancers should only modify the queue from the application
+ * main thread, switching thread either themselves or using this convenience
+ * function that does so.
+ *
+ * Note that this function will do no operation if called when there is no player
+ * set yet (e.g. inside enhancer construction) or if enhancer outlived the parent
+ * instance somehow. Both cases are considered to be implementation bug.
+ *
+ * Since: 0.10
+ */
+void
+clapper_reactable_queue_clear_sync (ClapperReactable *self)
+{
+  ClapperQueue *queue;
+
+  g_return_if_fail (CLAPPER_IS_REACTABLE (self));
+
+  CLAPPER_REACTABLE_DO_WITH_QUEUE (self, &queue, {
+    clapper_utils_queue_clear_on_main_sync (queue);
+  });
+}

src/lib/clapper/clapper-reactable.h

@@ -0,0 +1,228 @@
+/* Clapper Playback Library
+ * Copyright (C) 2025 Rafał Dzięgiel <rafostar.github@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#if !defined(__CLAPPER_INSIDE__) && !defined(CLAPPER_COMPILATION)
+#error "Only <clapper/clapper.h> can be included directly."
+#endif
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gst/gst.h>
+
+#include <clapper/clapper-visibility.h>
+#include <clapper/clapper-player.h>
+#include <clapper/clapper-enums.h>
+
+G_BEGIN_DECLS
+
+#define CLAPPER_TYPE_REACTABLE (clapper_reactable_get_type())
+#define CLAPPER_REACTABLE_CAST(obj) ((ClapperReactable *)(obj))
+
+CLAPPER_API
+G_DECLARE_INTERFACE (ClapperReactable, clapper_reactable, CLAPPER, REACTABLE, GstObject)
+
+/**
+ * ClapperReactableInterface:
+ * @parent_iface: The parent interface structure.
+ * @state_changed: Player state changed.
+ * @position_changed: Player position changed.
+ * @speed_changed: Player speed changed.
+ * @volume_changed: Player volume changed.
+ * @mute_changed: Player mute state changed.
+ * @played_item_changed: New media item started playing.
+ * @item_updated: An item in queue got updated.
+ * @queue_item_added: An item was added to the queue.
+ * @queue_item_removed: An item was removed from queue.
+ * @queue_item_repositioned: An item changed position within queue.
+ * @queue_cleared: All items were removed from queue.
+ * @queue_progression_changed: Progression mode of the queue was changed.
+ */
+struct _ClapperReactableInterface
+{
+  GTypeInterface parent_iface;
+
+  /**
+   * ClapperReactableInterface::state_changed:
+   * @reactable: a #ClapperReactable
+   * @state: a #ClapperPlayerState
+   *
+   * Player state changed.
+   *
+   * Since: 0.10
+   */
+  void (* state_changed) (ClapperReactable *reactable, ClapperPlayerState state);
+
+  /**
+   * ClapperReactableInterface::position_changed:
+   * @reactable: a #ClapperReactable
+   * @position: a decimal number with current position in seconds
+   *
+   * Player position changed.
+   *
+   * Since: 0.10
+   */
+  void (* position_changed) (ClapperReactable *reactable, gdouble position);
+
+  /**
+   * ClapperReactableInterface::speed_changed:
+   * @reactable: a #ClapperReactable
+   * @speed: the playback speed multiplier
+   *
+   * Player speed changed.
+   *
+   * Since: 0.10
+   */
+  void (* speed_changed) (ClapperReactable *reactable, gdouble speed);
+
+  /**
+   * ClapperReactableInterface::volume_changed:
+   * @reactable: a #ClapperReactable
+   * @volume: the volume level
+   *
+   * Player volume changed.
+   *
+   * Since: 0.10
+   */
+  void (* volume_changed) (ClapperReactable *reactable, gdouble volume);
+
+  /**
+   * ClapperReactableInterface::mute_changed:
+   * @reactable: a #ClapperReactable
+   * @mute: %TRUE if player is muted, %FALSE otherwise
+   *
+   * Player mute state changed.
+   *
+   * Since: 0.10
+   */
+  void (* mute_changed) (ClapperReactable *reactable, gboolean mute);
+
+  /**
+   * ClapperReactableInterface::played_item_changed:
+   * @reactable: a #ClapperReactable
+   * @item: a #ClapperMediaItem that is now playing
+   *
+   * New media item started playing. All following events (such as position changes)
+   * will be related to this @item from now on.
+   *
+   * Since: 0.10
+   */
+  void (* played_item_changed) (ClapperReactable *reactable, ClapperMediaItem *item);
+
+  /**
+   * ClapperReactableInterface::item_updated:
+   * @reactable: a #ClapperReactable
+   * @item: a #ClapperMediaItem that was updated
+   * @flags: flags informing which properties were updated
+   *
+   * An item in queue got updated.
+   *
+   * This might be (or not) currently played item.
+   * Implementations can compare it against the last item from
+   * [vfunc@Clapper.Reactable.played_item_changed] if they
+   * need to know that.
+   *
+   * Since: 0.10
+   */
+  void (* item_updated) (ClapperReactable *reactable, ClapperMediaItem *item, ClapperReactableItemUpdatedFlags flags);
+
+  /**
+   * ClapperReactableInterface::queue_item_added:
+   * @reactable: a #ClapperReactable
+   * @item: a #ClapperMediaItem that was added
+   * @index: position at which @item was placed in queue
+   *
+   * An item was added to the queue.
+   *
+   * Since: 0.10
+   */
+  void (* queue_item_added) (ClapperReactable *reactable, ClapperMediaItem *item, guint index);
+
+  /**
+   * ClapperReactableInterface::queue_item_removed:
+   * @reactable: a #ClapperReactable
+   * @item: a #ClapperMediaItem that was removed
+   * @index: position from which @item was removed in queue
+   *
+   * An item was removed from queue.
+   *
+   * Implementations that are interested in queue items removal
+   * should also implement [vfunc@Clapper.Reactable.queue_cleared].
+   *
+   * Since: 0.10
+   */
+  void (* queue_item_removed) (ClapperReactable *reactable, ClapperMediaItem *item, guint index);
+
+  /**
+   * ClapperReactableInterface::queue_item_repositioned:
+   * @reactable: a #ClapperReactable
+   * @before: position from which #ClapperMediaItem was removed
+   * @after: position at which #ClapperMediaItem was inserted after removal
+   *
+   * An item changed position within queue.
+   *
+   * Since: 0.10
+   */
+  void (* queue_item_repositioned) (ClapperReactable *reactable, guint before, guint after);
+
+  /**
+   * ClapperReactableInterface::queue_cleared:
+   * @reactable: a #ClapperReactable
+   *
+   * All items were removed from queue.
+   *
+   * Note that in such event [vfunc@Clapper.Reactable.queue_item_removed]
+   * will NOT be called for each item for performance reasons. You probably
+   * want to implement this function if you also implemented item removal.
+   *
+   * Since: 0.10
+   */
+  void (* queue_cleared) (ClapperReactable *reactable);
+
+  /**
+   * ClapperReactableInterface::queue_progression_changed:
+   * @reactable: a #ClapperReactable
+   * @mode: a #ClapperQueueProgressionMode
+   *
+   * Progression mode of the queue was changed.
+   *
+   * Since: 0.10
+   */
+  void (* queue_progression_changed) (ClapperReactable *reactable, ClapperQueueProgressionMode mode);
+
+  /*< private >*/
+  gpointer padding[8];
+};
+
+CLAPPER_API
+ClapperPlayer * clapper_reactable_get_player (ClapperReactable *reactable);
+
+CLAPPER_API
+void clapper_reactable_queue_append_sync (ClapperReactable *reactable, ClapperMediaItem *item);
+
+CLAPPER_API
+void clapper_reactable_queue_insert_sync (ClapperReactable *reactable, ClapperMediaItem *item, ClapperMediaItem *after_item);
+
+CLAPPER_API
+void clapper_reactable_queue_remove_sync (ClapperReactable *reactable, ClapperMediaItem *item);
+
+CLAPPER_API
+void clapper_reactable_queue_clear_sync (ClapperReactable *reactable);
+
+G_END_DECLS