Expose GData 'parent' and 'position' task fieldsgbsneto/gdata-task-position

The 'parent' property of the GDataTasksTask object is exposed
through ICAL_RELATEDTO_PROPERTY, which matches the practices
of GNOME To Do and NextCloud and other ICal-based providers.

The position, however, is exposed through an X ICal property
named X-EVOLUTION-GTASKS-POSITION. This doesn't affect Evolution
in any form, but will still allow external consumers of EDS to
retrieve the position of the task. Since GData tasks themselves
aren't backed by ICal components, we have some creative freedom
to use X properties.

Updating the task position and parent requires [1] but a compile
check was added to not force EDS to bump the libgdata version.

[1] https://gitlab.gnome.org/GNOME/libgdata/merge_requests/4

1 files changed, 49 insertions, 0 deletions

diff --git a/src/calendar/backends/gtasks/e-cal-backend-gtasks.c b/src/calendar/backends/gtasks/e-cal-backend-gtasks.c
index 5f0e005c9..64b8a6c54 100644
--- a/src/calendar/backends/gtasks/e-cal-backend-gtasks.c
+++ b/src/calendar/backends/gtasks/e-cal-backend-gtasks.c
@@ -32,6 +32,7 @@
 
 #define GTASKS_DEFAULT_TASKLIST_NAME "@default"
 #define X_EVO_GTASKS_SELF_LINK	"X-EVOLUTION-GTASKS-SELF-LINK"
+#define X_EVO_GTASKS_POSITION	"X-EVOLUTION-GTASKS-POSITION"
 
 /* Current data version; when doesn't match with the stored,
    then fetches everything again. */
@@ -100,6 +101,8 @@ ecb_gtasks_gdata_to_comp (GDataTasksTask *task)
 	GDataLink *data_link;
 	ECalComponent *comp;
 	icalcomponent *icomp;
+	const gchar *position;
+	const gchar *parent;
 	const gchar *text;
 	struct icaltimetype tt;
 
@@ -165,6 +168,14 @@ ecb_gtasks_gdata_to_comp (GDataTasksTask *task)
 	if (data_link)
 		e_cal_util_set_x_property (icomp, X_EVO_GTASKS_SELF_LINK, gdata_link_get_uri (data_link));
 
+	position = gdata_tasks_task_get_position (task);
+	if (position)
+		e_cal_util_set_x_property (icomp, X_EVO_GTASKS_POSITION, position);
+
+	parent = gdata_tasks_task_get_parent (task);
+	if (parent)
+		icalcomponent_add_property (icomp, icalproperty_new_relatedto (parent));
+
 	comp = e_cal_component_new_from_icalcomponent (icomp);
 	g_warn_if_fail (comp != NULL);
 
@@ -181,6 +192,9 @@ ecb_gtasks_comp_to_gdata (ECalComponent *comp,
 	icalcomponent *icomp;
 	icalproperty *prop;
 	const gchar *text;
+#if GDATA_CHECK_VERSION(0, 17, 10)
+	gchar *position;
+#endif
 	gchar *tmp;
 	struct icaltimetype tt;
 
@@ -252,6 +266,41 @@ ecb_gtasks_comp_to_gdata (ECalComponent *comp,
 
 	g_free (tmp);
 
+#if GDATA_CHECK_VERSION(0, 17, 10)
+	/* Position */
+	position = e_cal_util_dup_x_property (icomp, X_EVO_GTASKS_POSITION);
+	if (!position || !*position) {
+		g_free (position);
+		position = NULL;
+
+		/* If the passed-in component doesn't contain the libgdata position,
+		   then get it from the cached comp */
+		if (cached_comp) {
+			position = e_cal_util_dup_x_property (
+				e_cal_component_get_icalcomponent (cached_comp),
+				X_EVO_GTASKS_POSITION);
+		}
+	}
+
+	if (position && *position)
+		gdata_tasks_task_set_position (task, position);
+
+	g_free (position);
+
+	/* Parent */
+	prop = icalcomponent_get_first_property (icomp, ICAL_RELATEDTO_PROPERTY);
+	if (!prop && cached_comp) {
+		icalcomponent *cached_icomp;
+		cached_icomp = e_cal_component_get_icalcomponent (cached_comp);
+		prop = icalcomponent_get_first_property (
+			cached_icomp,
+			ICAL_RELATEDTO_PROPERTY);
+	}
+
+	if (prop)
+		gdata_tasks_task_set_parent (task, icalproperty_get_relatedto (prop));
+#endif
+
 	return task;
 }