[tracker-miners/wip/carlosg/writeback-musicbrainz] tracker-writeback: Support musicbrainz tags in gstreamer module

[Carlos Garnacho <carlosg src gnome org>]

commit 654ccd04e546fb0b64068861f463a0db88ee514b
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sun Jun 28 20:34:20 2020 +0200

    tracker-writeback: Support musicbrainz tags in gstreamer module

 .../tracker-writeback-gstreamer.c                  | 85 ++++++++++++++++++++++
 1 file changed, 85 insertions(+)
---
diff --git a/src/tracker-writeback/tracker-writeback-gstreamer.c 
b/src/tracker-writeback/tracker-writeback-gstreamer.c
index fbe8983d0..20155b7e6 100644
--- a/src/tracker-writeback/tracker-writeback-gstreamer.c
+++ b/src/tracker-writeback/tracker-writeback-gstreamer.c
@@ -576,6 +576,63 @@ writeback_gstreamer_set (TagElements  *element,
        return TRUE;
 }
 
+static void
+handle_musicbrainz_tags (TrackerResource     *resource,
+                        const gchar         *prop,
+                        TagElements         *element,
+                        const gchar * const *allowed_tags)
+{
+       GList *references, *r;
+
+       references = tracker_resource_get_values (resource, prop);
+
+       for (r = references; r; r = r->next) {
+               TrackerResource *ref;
+               GValue *value, val = G_VALUE_INIT;
+               const gchar *source, *identifier;
+
+               value = r->data;
+
+               if (!G_VALUE_HOLDS (value, TRACKER_TYPE_RESOURCE))
+                       continue;
+
+               ref = g_value_get_object (value);
+
+               source = tracker_resource_get_first_uri (ref, "tracker:referenceSource");
+               identifier = tracker_resource_get_first_string (ref, "tracker:referenceIdentifier");
+
+               if (!source || !g_strv_contains (allowed_tags, source))
+                       continue;
+
+               if (g_strcmp0 (source, "https://musicbrainz.org/doc/Recording";) == 0) {
+                       g_value_init (&val, G_TYPE_STRING);
+                       g_value_set_string (&val, identifier);
+                       writeback_gstreamer_set (element, GST_TAG_MUSICBRAINZ_TRACKID, &val);
+                       g_value_unset (&val);
+               } else if (g_strcmp0 (source, "https://musicbrainz.org/doc/Track";) == 0) {
+                       g_value_init (&val, G_TYPE_STRING);
+                       g_value_set_string (&val, identifier);
+                       writeback_gstreamer_set (element, GST_TAG_MUSICBRAINZ_RELEASETRACKID, &val);
+                       g_value_unset (&val);
+               } else if (g_strcmp0 (source, "https://musicbrainz.org/doc/Release";) == 0) {
+                       g_value_init (&val, G_TYPE_STRING);
+                       g_value_set_string (&val, identifier);
+                       writeback_gstreamer_set (element, GST_TAG_MUSICBRAINZ_ALBUMID, &val);
+                       g_value_unset (&val);
+               } else if (g_strcmp0 (source, "https://musicbrainz.org/doc/Release_Group";) == 0) {
+                       g_value_init (&val, G_TYPE_STRING);
+                       g_value_set_string (&val, identifier);
+                       writeback_gstreamer_set (element, GST_TAG_MUSICBRAINZ_RELEASEGROUPID, &val);
+                       g_value_unset (&val);
+               } else if (g_strcmp0 (source, "https://musicbrainz.org/doc/Artist";) == 0) {
+                       g_value_init (&val, G_TYPE_STRING);
+                       g_value_set_string (&val, identifier);
+                       writeback_gstreamer_set (element, GST_TAG_MUSICBRAINZ_ARTISTID, &val);
+                       g_value_unset (&val);
+               }
+       }
+}
+
 static gboolean
 writeback_gstreamer_write_file_metadata (TrackerWritebackFile  *writeback,
                                          GFile                 *file,
@@ -640,12 +697,20 @@ writeback_gstreamer_write_file_metadata (TrackerWritebackFile  *writeback,
                if (g_strcmp0 (prop, "nmm:performer") == 0) {
                        TrackerResource *performer;
                        const gchar *name = NULL;
+                       const gchar *mb_tags[] = {
+                               "https://musicbrainz.org/doc/Artist";,
+                               NULL,
+                       };
 
                        performer = tracker_resource_get_first_relation (resource, prop);
 
                        if (performer) {
                                name = tracker_resource_get_first_string (performer,
                                                                          "nmm:artistName");
+
+                               handle_musicbrainz_tags (performer,
+                                                        "tracker:hasExternalReference",
+                                                        element, mb_tags);
                        }
 
                        if (name) {
@@ -790,12 +855,22 @@ writeback_gstreamer_write_file_metadata (TrackerWritebackFile  *writeback,
                        disc = tracker_resource_get_first_relation (resource, prop);
 
                        if (disc) {
+                               const gchar *mb_tags[] = {
+                                       "https://musicbrainz.org/doc/Release";,
+                                       "https://musicbrainz.org/doc/Release_Group";,
+                                       NULL,
+                               };
+
                                number = tracker_resource_get_first_int (disc,
                                                                         "nmm:setNumber");
                                g_value_init (&val, G_TYPE_INT);
                                g_value_set_int (&val, number);
                                writeback_gstreamer_set (element, GST_TAG_ALBUM_VOLUME_NUMBER, &val);
                                g_value_unset (&val);
+
+                               handle_musicbrainz_tags (disc,
+                                                        "tracker:hasExternalReference",
+                                                        element, mb_tags);
                        }
                }
 
@@ -859,6 +934,16 @@ writeback_gstreamer_write_file_metadata (TrackerWritebackFile  *writeback,
                        g_string_free (keyword_str, TRUE);
                        g_list_free (keywords);
                }
+
+               if (g_strcmp0 (prop, "tracker:hasExternalReference") == 0) {
+                       const gchar *mb_tags[] = {
+                               "https://musicbrainz.org/doc/Recording";,
+                               "https://musicbrainz.org/doc/Track";,
+                               NULL,
+                       };
+
+                       handle_musicbrainz_tags (resource, prop, element, mb_tags);
+               }
        }
 
        writeback_gstreamer_save (element, file, error);