libsysprof-gtk: add tracks model to session

The goal here is for the session to decode information from the document
and then determine what tracks can be displayed. This is what an "aid"
used to do in libsysprof-ui. I think we can just centralize it now that
we have a lot more abstractions in SysprofDocument.

src/libsysprof-gtk/sysprof-session.c

@@ -21,6 +21,7 @@
 #include "config.h"
 
 #include "sysprof-session.h"
+#include "sysprof-track.h"
 #include "sysprof-value-axis.h"
 
 struct _SysprofSession
@@ -30,6 +31,8 @@ struct _SysprofSession
   SysprofDocument *document;
   GtkEveryFilter  *filter;
 
+  GListStore      *tracks;
+
   SysprofAxis     *visible_time_axis;
   SysprofAxis     *selected_time_axis;
 
@@ -42,8 +45,9 @@ enum {
   PROP_DOCUMENT,
   PROP_FILTER,
   PROP_SELECTED_TIME,
-  PROP_VISIBLE_TIME,
   PROP_SELECTED_TIME_AXIS,
+  PROP_TRACKS,
+  PROP_VISIBLE_TIME,
   PROP_VISIBLE_TIME_AXIS,
   N_PROPS
 };
@@ -88,6 +92,7 @@ sysprof_session_dispose (GObject *object)
 {
   SysprofSession *self = (SysprofSession *)object;
 
+  g_clear_object (&self->tracks);
   g_clear_object (&self->visible_time_axis);
   g_clear_object (&self->selected_time_axis);
   g_clear_object (&self->document);
@@ -130,6 +135,10 @@ sysprof_session_get_property (GObject    *object,
       g_value_set_object (value, sysprof_session_get_visible_time_axis (self));
       break;
 
+    case PROP_TRACKS:
+      g_value_take_object (value, sysprof_session_list_tracks (self));
+      break;
+
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -193,6 +202,11 @@ sysprof_session_class_init (SysprofSessionClass *klass)
                          SYSPROF_TYPE_AXIS,
                          (G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
 
+  properties[PROP_TRACKS] =
+    g_param_spec_object ("tracks", NULL, NULL,
+                         G_TYPE_LIST_MODEL,
+                         (G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS));
+
   g_object_class_install_properties (object_class, N_PROPS, properties);
 }
 
@@ -202,6 +216,7 @@ sysprof_session_init (SysprofSession *self)
   self->filter = gtk_every_filter_new ();
   self->selected_time_axis = sysprof_value_axis_new (0, 0);
   self->visible_time_axis = sysprof_value_axis_new (0, 0);
+  self->tracks = g_list_store_new (SYSPROF_TYPE_TRACK);
 }
 
 SysprofSession *
@@ -324,3 +339,19 @@ sysprof_session_get_visible_time_axis (SysprofSession *self)
 
   return self->visible_time_axis;
 }
+
+/**
+ * sysprof_session_list_tracks:
+ * @self: a #SysprofSession
+ *
+ * Gets a list of #SysprofTrack to be displayed in the session.
+ *
+ * Returns: (transfer full): a #GListModel of #SysprofTrack
+ */
+GListModel *
+sysprof_session_list_tracks (SysprofSession *self)
+{
+  g_return_val_if_fail (SYSPROF_IS_SESSION (self), NULL);
+
+  return g_object_ref (G_LIST_MODEL (self->tracks));
+}

src/libsysprof-gtk/sysprof-session.h

@@ -51,5 +51,7 @@ SysprofAxis           *sysprof_session_get_selected_time_axis (SysprofSession
 SYSPROF_AVAILABLE_IN_ALL
 void                   sysprof_session_select_time            (SysprofSession        *self,
                                                                const SysprofTimeSpan *time_span);
+SYSPROF_AVAILABLE_IN_ALL
+GListModel            *sysprof_session_list_tracks            (SysprofSession        *self);
 
 G_END_DECLS