[evolution-data-server] I#234 - EReminderWatcher: Auto-remove old reminders

[Milan Crha <mcrha src gnome org>]

commit c349266e0fe3fed7066e3b42aa28feb0ccebfbf6
Author: Milan Crha <mcrha redhat com>
Date:   Wed Jun 29 17:00:11 2022 +0200

    I#234 - EReminderWatcher: Auto-remove old reminders
    
    The "reminders-past-days" GSettings option hold how many days old the past reminders
    can be. The older reminders are auto-removed once per day. A special value "0" can
    be used to not auto-remove the reminders.
    
    Related to https://gitlab.gnome.org/GNOME/evolution-data-server/-/issues/234

 ...e.evolution-data-server.calendar.gschema.xml.in |  4 ++
 src/calendar/libecal/e-reminder-watcher.c          | 78 ++++++++++++++++++++++
 2 files changed, 82 insertions(+)
---
diff --git a/data/org.gnome.evolution-data-server.calendar.gschema.xml.in 
b/data/org.gnome.evolution-data-server.calendar.gschema.xml.in
index 586f5c2bd..e77d88e45 100644
--- a/data/org.gnome.evolution-data-server.calendar.gschema.xml.in
+++ b/data/org.gnome.evolution-data-server.calendar.gschema.xml.in
@@ -32,6 +32,10 @@
       <default>['']</default>
       <summary>Snoozed reminders for EReminderWatcher</summary>
     </key>
+    <key name="reminders-past-days" type="i">
+      <default>7</default>
+      <summary>How many days the reminders-past can hold back. Reminders older than these days are 
automatically removed from the list of the past reminders. Use '0' to not remove old reminders.</summary>
+    </key>
 
     <key name="notify-programs" type="as">
       <default>[]</default>
diff --git a/src/calendar/libecal/e-reminder-watcher.c b/src/calendar/libecal/e-reminder-watcher.c
index 8a14ecc84..52095a439 100644
--- a/src/calendar/libecal/e-reminder-watcher.c
+++ b/src/calendar/libecal/e-reminder-watcher.c
@@ -79,6 +79,7 @@ struct _EReminderWatcherPrivate {
 
        gint64 next_midnight;
        gint64 next_trigger;
+       gint64 last_cleanup_date;
 };
 
 enum {
@@ -1721,6 +1722,81 @@ e_reminder_watcher_add (GSList **inout_reminders, /* EReminderData * */
        return TRUE;
 }
 
+static void
+e_reminder_watcher_cleanup_past_reminders (EReminderWatcher *watcher)
+{
+       gint64 reminders_past_days;
+       gint64 check_date; /* midnight / (24 * 60 * 60) */
+       time_t now, midnight;
+
+       g_rec_mutex_lock (&watcher->priv->lock);
+
+       reminders_past_days = g_settings_get_int (watcher->priv->settings, "reminders-past-days");
+       if (!reminders_past_days) {
+               g_rec_mutex_unlock (&watcher->priv->lock);
+               return;
+       } else if (reminders_past_days < 1) {
+               reminders_past_days = 1;
+       }
+
+       now = time (NULL);
+       midnight = time_day_end_with_zone (now, watcher->priv->default_zone);
+
+       while (midnight <= now) {
+               now += 60 * 60; /* increment one day */
+               midnight = time_day_end_with_zone (now, watcher->priv->default_zone);
+       }
+
+       check_date = midnight / (24 * 60 * 60);
+
+       if (check_date != watcher->priv->last_cleanup_date) {
+               GSList *past_reminders, *new_past_reminders = NULL, *link;
+               guint64 n_removed = 0;
+
+               watcher->priv->last_cleanup_date = check_date;
+
+               past_reminders = e_reminder_watcher_dup_past (watcher);
+
+               for (link = past_reminders; link; link = g_slist_next (link)) {
+                       EReminderData *rd = link->data;
+                       gint64 diff;
+
+                       diff = (g_get_real_time () / G_USEC_PER_SEC) - ((gint64) 
e_cal_component_alarm_instance_get_occur_start (rd->instance));
+                       if (diff > 0) {
+                               diff /= 60 * 60 * 24;
+
+                               if (diff <= reminders_past_days) {
+                                       new_past_reminders = g_slist_prepend (new_past_reminders, rd);
+                               } else {
+                                       n_removed++;
+                                       e_reminder_watcher_debug_print ("Auto-removed reminder from past for 
'%s' from %s at %s due to being %" G_GINT64_FORMAT " days old\n",
+                                               i_cal_component_get_summary 
(e_cal_component_get_icalcomponent (rd->component)),
+                                               rd->source_uid,
+                                               e_reminder_watcher_timet_as_string 
(e_cal_component_alarm_instance_get_time (rd->instance)),
+                                               diff);
+                               }
+                       } else {
+                               new_past_reminders = g_slist_prepend (new_past_reminders, rd);
+                       }
+               }
+
+               if (n_removed > 0) {
+                       e_reminder_watcher_debug_print ("Auto-removed %" G_GUINT64_FORMAT " past reminders 
older than %" G_GINT64_FORMAT " days, left %d reminders\n",
+                               n_removed, reminders_past_days, g_slist_length (new_past_reminders));
+
+                       new_past_reminders = g_slist_reverse (new_past_reminders);
+
+                       e_reminder_watcher_save_past (watcher, new_past_reminders);
+                       e_reminder_watcher_emit_signal_idle (watcher, signals[CHANGED], NULL);
+               }
+
+               g_slist_free_full (past_reminders, e_reminder_data_free);
+               g_slist_free (new_past_reminders);
+       }
+
+       g_rec_mutex_unlock (&watcher->priv->lock);
+}
+
 static void
 e_reminder_watcher_gather_nearest_scheduled_cb (gpointer key,
                                                gpointer value,
@@ -1755,6 +1831,8 @@ e_reminder_watcher_maybe_schedule_next_trigger (EReminderWatcher *watcher,
 {
        g_rec_mutex_lock (&watcher->priv->lock);
 
+       e_reminder_watcher_cleanup_past_reminders (watcher);
+
        if (!watcher->priv->timers_enabled) {
                g_rec_mutex_unlock (&watcher->priv->lock);
                return;