[gnome-calendar] contrib: Bring ECalDataModel changes

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 98ec549967bd8c526cd716e8de8b5c1fe24967ab
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Tue Jul 24 19:02:07 2018 -0300

    contrib: Bring ECalDataModel changes
    
    This particular changeset is important because it fixes that
    annoying issue of the event staying when edited out of the
    range (out of the month in Month view, week in Week view,
    etc).
    
    Commit: https://gitlab.gnome.org/GNOME/evolution/commit/3cea6c53337382330c443f50f858424ead2005b6

 contrib/evolution/e-cal-data-model.c | 71 ++++++++++++++++++++++++++++++++++--
 1 file changed, 68 insertions(+), 3 deletions(-)
---
diff --git a/contrib/evolution/e-cal-data-model.c b/contrib/evolution/e-cal-data-model.c
index 85cb8f53..7ab6169d 100644
--- a/contrib/evolution/e-cal-data-model.c
+++ b/contrib/evolution/e-cal-data-model.c
@@ -663,6 +663,19 @@ cal_data_model_thaw_all_subscribers (ECalDataModel *data_model)
        cal_data_model_foreach_subscriber (data_model, NULL, cal_data_model_thaw_subscriber_cb, NULL);
 }
 
+static void
+cal_data_model_gather_subscribers_cb (ECalDataModel *data_model,
+                                     ECalClient *client,
+                                     ECalDataModelSubscriber *subscriber,
+                                     gpointer user_data)
+{
+       GHashTable *subscribers = user_data;
+
+       g_return_if_fail (subscribers != NULL);
+
+       g_hash_table_insert (subscribers, g_object_ref (subscriber), NULL);
+}
+
 static void
 cal_data_model_add_component_cb (ECalDataModel *data_model,
                                 ECalClient *client,
@@ -850,8 +863,9 @@ cal_data_model_process_added_component (ECalDataModel *data_model,
                                        ComponentData *comp_data,
                                        GHashTable *known_instances)
 {
-       ECalComponentId *id;
+       ECalComponentId *id, *old_id = NULL;
        ComponentData *old_comp_data = NULL;
+       time_t old_instance_start = (time_t) 0, old_instance_end = (time_t) 0;
        gboolean comp_data_equal;
 
        g_return_if_fail (data_model != NULL);
@@ -881,6 +895,12 @@ cal_data_model_process_added_component (ECalDataModel *data_model,
 
        comp_data_equal = component_data_equal (comp_data, old_comp_data);
 
+       if (old_comp_data) {
+               old_id = e_cal_component_get_id (old_comp_data->component);
+               old_instance_start = old_comp_data->instance_start;
+               old_instance_end = old_comp_data->instance_end;
+       }
+
        if (view_data->lost_components)
                g_hash_table_remove (view_data->lost_components, id);
 
@@ -893,17 +913,62 @@ cal_data_model_process_added_component (ECalDataModel *data_model,
        g_hash_table_insert (view_data->components, id, comp_data);
 
        if (!comp_data_equal) {
-               if (!old_comp_data)
+               if (!old_comp_data) {
                        cal_data_model_foreach_subscriber_in_range (data_model, view_data->client,
                                comp_data->instance_start, comp_data->instance_end,
                                cal_data_model_add_component_cb, comp_data->component);
-               else
+               } else if (comp_data->instance_start != old_instance_start ||
+                          comp_data->instance_end != old_instance_end) {
+                       /* Component moved to a different time; some subscribers may lose it,
+                          some may just modify it, some may have it added. */
+                       GHashTable *old_subscribers, *new_subscribers;
+                       GHashTableIter iter;
+                       gpointer key;
+
+                       old_subscribers = g_hash_table_new_full (g_direct_hash, g_direct_equal, 
g_object_unref, NULL);
+                       new_subscribers = g_hash_table_new_full (g_direct_hash, g_direct_equal, 
g_object_unref, NULL);
+
+                       cal_data_model_foreach_subscriber_in_range (data_model, view_data->client,
+                               old_instance_start, old_instance_end,
+                               cal_data_model_gather_subscribers_cb, old_subscribers);
+
+                       cal_data_model_foreach_subscriber_in_range (data_model, view_data->client,
+                               comp_data->instance_start, comp_data->instance_end,
+                               cal_data_model_gather_subscribers_cb, new_subscribers);
+
+                       g_hash_table_iter_init (&iter, old_subscribers);
+                       while (g_hash_table_iter_next (&iter, &key, NULL)) {
+                               ECalDataModelSubscriber *subscriber = key;
+
+                               /* If in both hashes, then the subscriber can be notified with 'modified',
+                                  otherwise the component had been 'removed' for it. */
+                               if (g_hash_table_remove (new_subscribers, subscriber))
+                                       e_cal_data_model_subscriber_component_modified (subscriber, 
view_data->client, comp_data->component);
+                               else if (old_id)
+                                       e_cal_data_model_subscriber_component_removed (subscriber, 
view_data->client, old_id->uid, old_id->rid);
+                       }
+
+                       /* Those which left in the new_subscribers have the component added. */
+                       g_hash_table_iter_init (&iter, new_subscribers);
+                       while (g_hash_table_iter_next (&iter, &key, NULL)) {
+                               ECalDataModelSubscriber *subscriber = key;
+
+                               e_cal_data_model_subscriber_component_added (subscriber, view_data->client, 
comp_data->component);
+                       }
+
+                       g_hash_table_destroy (old_subscribers);
+                       g_hash_table_destroy (new_subscribers);
+               } else {
                        cal_data_model_foreach_subscriber_in_range (data_model, view_data->client,
                                comp_data->instance_start, comp_data->instance_end,
                                cal_data_model_modify_component_cb, comp_data->component);
+               }
        }
 
        view_data_unlock (view_data);
+
+       if (old_id)
+               e_cal_component_free_id (old_id);
 }
 
 typedef struct _GatherComponentsData {