formatter: Add a method to retrieve the best formatter for a givent URI

Uses the file extension as hint falling back to the default formatter
if none is found

Make use of that function in when saving a project and not formatter
is specified.

ges/ges-formatter.c

@@ -680,3 +680,56 @@ _find_formatter_asset_for_id (const gchar * id)
 
   return asset;
 }
+
+/**
+ * ges_find_formatter_for_uri:
+ *
+ * Get the best formatter for @uri. It tries to find a formatter
+ * compatible with @uri extension, if none is found, it returns the default
+ * formatter asset.
+ *
+ * Returns: (transfer none): The #GESAsset for the best formatter to save to @uri
+ *
+ * Since: 1.18
+ */
+GESAsset *
+ges_find_formatter_for_uri (const gchar * uri)
+{
+  GList *formatter_assets, *tmp;
+  GESAsset *asset = NULL;
+
+  gchar *extension = _get_extension (uri);
+  if (!extension)
+    return ges_formatter_get_default ();
+
+  formatter_assets = g_list_sort (ges_list_assets (GES_TYPE_FORMATTER),
+      (GCompareFunc) _sort_formatters);
+
+  for (tmp = formatter_assets; tmp; tmp = tmp->next) {
+    gint i;
+    gchar **valid_exts =
+        g_strsplit (ges_meta_container_get_string (GES_META_CONTAINER
+            (tmp->data),
+            GES_META_FORMATTER_EXTENSION), ",", -1);
+
+    for (i = 0; valid_exts[i]; i++) {
+      if (!g_strcmp0 (extension, valid_exts[i])) {
+        asset = GES_ASSET (tmp->data);
+        break;
+      }
+    }
+
+    g_strfreev (valid_exts);
+    if (asset)
+      break;
+  }
+  g_free (extension);
+  g_list_free (formatter_assets);
+
+  if (asset) {
+    GST_INFO_OBJECT (asset, "Using for URI %s", uri);
+    return asset;
+  }
+
+  return ges_formatter_get_default ();
+}

ges/ges-formatter.h

@@ -175,6 +175,9 @@ gboolean ges_formatter_save_to_uri      (GESFormatter * formatter,
 GES_API
 GESAsset *ges_formatter_get_default    (void);
 
+GES_API
+GESAsset *ges_find_formatter_for_uri   (const gchar *uri);
+
 G_END_DECLS
 
 #endif /* _GES_FORMATTER */

ges/ges-project.c

@@ -1058,7 +1058,7 @@ ges_project_list_assets (GESProject * project, GType filter)
  * @uri: The uri where to save @project and @timeline
  * @formatter_asset: (allow-none): The formatter asset to use or %NULL. If %NULL,
  * will try to save in the same format as the one from which the timeline as been loaded
- * or default to the formatter with highest rank
+ * or default to the best formatter as defined in #ges_find_formatter_for_uri
  * @overwrite: %TRUE to overwrite file if it exists
  * @error: (out) (allow-none): An error to be set in case something wrong happens or %NULL
  *
@@ -1105,8 +1105,9 @@ ges_project_save (GESProject * project, GESTimeline * timeline,
     goto out;
   }
 
-  if (formatter_asset == NULL)
-    formatter_asset = gst_object_ref (ges_formatter_get_default ());
+  if (formatter_asset == NULL) {
+    formatter_asset = gst_object_ref (ges_find_formatter_for_uri (uri));
+  }
 
   formatter = GES_FORMATTER (ges_asset_extract (formatter_asset, error));
   if (formatter == NULL) {