path: root/calendar/gui/alarm-notify/alarm-queue.c

/* Evolution calendar - Alarm queueing engine
 *
 * Copyright (C) 2001 Ximian, Inc.
 *
 * Authors: Federico Mena-Quintero <federico@ximian.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <string.h>
#include <glib.h>
#include <bonobo-activation/bonobo-activation.h>
#include <bonobo/bonobo-object.h>
#include <bonobo/bonobo-exception.h>
#include <gtk/gtksignal.h>
#include <gtk/gtkbox.h>
#include <gtk/gtkdialog.h>
#include <gtk/gtkeventbox.h>
#include <gtk/gtkimage.h>
#include <gtk/gtkimagemenuitem.h>
#include <gtk/gtklabel.h>
#include <gtk/gtkcheckbutton.h>
#include <gtk/gtkstock.h>
#include <gtk/gtktooltips.h>
#include <libgnome/gnome-i18n.h>
#include <libgnome/gnome-exec.h>
#include <libgnome/gnome-sound.h>
#include <libgnomeui/gnome-dialog-util.h>
#include <libgnomeui/gnome-uidefs.h>
#include <e-util/eggtrayicon.h>
#include <e-util/e-icon-factory.h>
#include <libecal/e-cal-time-util.h>
#include "evolution-calendar.h"
#include "alarm.h"
#include "alarm-notify-dialog.h"
#include "alarm-queue.h"
#include "config-data.h"
#include "util.h"



/* Whether the queueing system has been initialized */
static gboolean alarm_queue_inited;

/* When the alarm queue system is inited, this gets set to the last time an
 * alarm notification was issued.  This lets us present any notifications that
 * should have happened while the alarm daemon was not running.
 */
static time_t saved_notification_time;

/* Clients we are monitoring for alarms */
static GHashTable *client_alarms_hash = NULL;

/* List of tray icons being displayed */
static GList *tray_icons_list = NULL;

/* Structure that stores a client we are monitoring */
typedef struct {
    /* Monitored client */
    ECal *client;

    /* The live query to the calendar */
    ECalView *query;

    /* Hash table of component UID -> CompQueuedAlarms.  If an element is
     * present here, then it means its cqa->queued_alarms contains at least
     * one queued alarm.  When all the alarms for a component have been
     * dequeued, the CompQueuedAlarms structure is removed from the hash
     * table.  Thus a CQA exists <=> it has queued alarms.
     */
    GHashTable *uid_alarms_hash;
} ClientAlarms;

/* Pair of a ECalComponentAlarms and the mapping from queued alarm IDs to the
 * actual alarm instance structures.
 */
typedef struct {
    /* The parent client alarms structure */
    ClientAlarms *parent_client;

    /* The component's UID */
    char *uid;

    /* The actual component and its alarm instances */
    ECalComponentAlarms *alarms;

    /* List of QueuedAlarm structures */
    GSList *queued_alarms;

    /* Flags */
    gboolean expecting_update;
} CompQueuedAlarms;

/* Pair of a queued alarm ID and the alarm trigger instance it refers to */
typedef struct {
    /* Alarm ID from alarm.h */
    gpointer alarm_id;

    /* Instance from our parent CompQueuedAlarms->alarms->alarms list */
    ECalComponentAlarmInstance *instance;

    /* Whether this is a snoozed queued alarm or a normal one */
    guint snooze : 1;
} QueuedAlarm;

/* Alarm ID for the midnight refresh function */
static gpointer midnight_refresh_id = NULL;

static void display_notification (time_t trigger, CompQueuedAlarms *cqa,
                  gpointer alarm_id, gboolean use_description);
static void audio_notification (time_t trigger, CompQueuedAlarms *cqa, gpointer alarm_id);
static void mail_notification (time_t trigger, CompQueuedAlarms *cqa, gpointer alarm_id);
static void procedure_notification (time_t trigger, CompQueuedAlarms *cqa, gpointer alarm_id);

static void query_objects_changed_cb (ECal *client, GList *objects, gpointer data);
static void query_objects_removed_cb (ECal *client, GList *objects, gpointer data);



/* Alarm queue engine */

static void load_alarms_for_today (ClientAlarms *ca);
static void midnight_refresh_cb (gpointer alarm_id, time_t trigger, gpointer data);

/* Queues an alarm trigger for midnight so that we can load the next day's worth
 * of alarms.
 */
static void
queue_midnight_refresh (void)
{
    time_t midnight;
    icaltimezone *zone;

    g_assert (midnight_refresh_id == NULL);

    zone = config_data_get_timezone ();

    midnight = time_day_end_with_zone (time (NULL), zone);

    midnight_refresh_id = alarm_add (midnight, midnight_refresh_cb, NULL, NULL);
    if (!midnight_refresh_id) {
        g_message ("queue_midnight_refresh(): Could not set up the midnight refresh alarm!");
        /* FIXME: what to do? */
    }
}

/* Loads a client's alarms; called from g_hash_table_foreach() */
static void
add_client_alarms_cb (gpointer key, gpointer value, gpointer data)
{
    ClientAlarms *ca;

    ca = value;
    load_alarms_for_today (ca);
}

/* Loads the alarms for the new day every midnight */
static void
midnight_refresh_cb (gpointer alarm_id, time_t trigger, gpointer data)
{
    /* Re-load the alarms for all clients */

    g_hash_table_foreach (client_alarms_hash, add_client_alarms_cb, NULL);

    /* Re-schedule the midnight update */

    midnight_refresh_id = NULL;
    queue_midnight_refresh ();
}

/* Looks up a client in the client alarms hash table */
static ClientAlarms *
lookup_client (ECal *client)
{
    return g_hash_table_lookup (client_alarms_hash, client);
}

/* Looks up a queued alarm based on its alarm ID */
static QueuedAlarm *
lookup_queued_alarm (CompQueuedAlarms *cqa, gpointer alarm_id)
{
    GSList *l;
    QueuedAlarm *qa;

    qa = NULL;

    for (l = cqa->queued_alarms; l; l = l->next) {
        qa = l->data;
        if (qa->alarm_id == alarm_id)
            return qa;
    }

    /* not found, might have been updated/removed */
    return NULL;
}

/* Removes an alarm from the list of alarms of a component.  If the alarm was
 * the last one listed for the component, it removes the component itself.
 */
static void
remove_queued_alarm (CompQueuedAlarms *cqa, gpointer alarm_id,
             gboolean free_object, gboolean remove_alarm)
{
    QueuedAlarm *qa;
    GSList *l;

    qa = NULL;

    for (l = cqa->queued_alarms; l; l = l->next) {
        qa = l->data;
        if (qa->alarm_id == alarm_id)
            break;
    }

    if (!l)
        return;

    cqa->queued_alarms = g_slist_remove_link (cqa->queued_alarms, l);
    g_slist_free_1 (l);

    if (remove_alarm) {
        cqa->expecting_update = TRUE;
        e_cal_discard_alarm (cqa->parent_client->client, cqa->alarms->comp,
                     qa->instance->auid, NULL);
        cqa->expecting_update = FALSE;
    }

    g_free (qa);

    /* If this was the last queued alarm for this component, remove the
     * component itself.
     */

    if (cqa->queued_alarms != NULL)
        return;

    if (free_object) {
        g_hash_table_remove (cqa->parent_client->uid_alarms_hash, cqa->uid);
        g_free (cqa->uid);
        cqa->uid = NULL;
        cqa->parent_client = NULL;
        e_cal_component_alarms_free (cqa->alarms);
        g_free (cqa);
    } else {
        e_cal_component_alarms_free (cqa->alarms);
        cqa->alarms = NULL;
    }
}

/* Callback used when an alarm triggers */
static void
alarm_trigger_cb (gpointer alarm_id, time_t trigger, gpointer data)
{
    CompQueuedAlarms *cqa;
    ECalComponent *comp;
    QueuedAlarm *qa;
    ECalComponentAlarm *alarm;
    ECalComponentAlarmAction action;

    cqa = data;
    comp = cqa->alarms->comp;

    config_data_set_last_notification_time (trigger);
    saved_notification_time = trigger;

    qa = lookup_queued_alarm (cqa, alarm_id);
    if (!qa)
        return;

    /* Decide what to do based on the alarm action.  We use the trigger that
     * is passed to us instead of the one from the instance structure
     * because this may be a snoozed alarm instead of an original
     * occurrence.
     */

    alarm = e_cal_component_get_alarm (comp, qa->instance->auid);
    g_assert (alarm != NULL);

    e_cal_component_alarm_get_action (alarm, &action);
    e_cal_component_alarm_free (alarm);

    switch (action) {
    case E_CAL_COMPONENT_ALARM_AUDIO:
        audio_notification (trigger, cqa, alarm_id);
        break;

    case E_CAL_COMPONENT_ALARM_DISPLAY:
        display_notification (trigger, cqa, alarm_id, TRUE);
        break;

    case E_CAL_COMPONENT_ALARM_EMAIL:
        mail_notification (trigger, cqa, alarm_id);
        break;

    case E_CAL_COMPONENT_ALARM_PROCEDURE:
        procedure_notification (trigger, cqa, alarm_id);
        break;

    default:
        g_assert_not_reached ();
        break;
    }
}

/* Adds the alarms in a ECalComponentAlarms structure to the alarms queued for a
 * particular client.  Also puts the triggers in the alarm timer queue.
 */
static void
add_component_alarms (ClientAlarms *ca, ECalComponentAlarms *alarms)
{
    const char *uid;
    CompQueuedAlarms *cqa;
    GSList *l;

    /* No alarms? */
    if (alarms == NULL || alarms->alarms == NULL) {
        g_message ("No alarms to add");
        if (alarms)
            e_cal_component_alarms_free (alarms);
        return;
    }

    cqa = g_new (CompQueuedAlarms, 1);
    cqa->parent_client = ca;
    cqa->alarms = alarms;
    cqa->expecting_update = FALSE;

    cqa->queued_alarms = NULL;

    for (l = alarms->alarms; l; l = l->next) {
        ECalComponentAlarmInstance *instance;
        gpointer alarm_id;
        QueuedAlarm *qa;

        instance = l->data;

        g_message ("Adding alarm at %lu (%lu)", instance->trigger, time (NULL));
        alarm_id = alarm_add (instance->trigger, alarm_trigger_cb, cqa, NULL);
        if (!alarm_id) {
            g_message ("add_component_alarms(): Could not schedule a trigger for "
                   "%ld, discarding...", (long) instance->trigger);
            continue;
        }

        qa = g_new (QueuedAlarm, 1);
        qa->alarm_id = alarm_id;
        qa->instance = instance;
        qa->snooze = FALSE;

        cqa->queued_alarms = g_slist_prepend (cqa->queued_alarms, qa);
    }

    e_cal_component_get_uid (alarms->comp, &uid);

    /* If we failed to add all the alarms, then we should get rid of the cqa */
    if (cqa->queued_alarms == NULL) {
        g_message ("add_component_alarms(): Could not add any of the alarms "
               "for the component `%s'; discarding it...", uid);

        e_cal_component_alarms_free (cqa->alarms);
        cqa->alarms = NULL;

        g_free (cqa);
        return;
    }

    cqa->queued_alarms = g_slist_reverse (cqa->queued_alarms);
    cqa->uid = g_strdup (uid);
    g_hash_table_insert (ca->uid_alarms_hash, cqa->uid, cqa);
}

/* Loads the alarms of a client for a given range of time */
static void
load_alarms (ClientAlarms *ca, time_t start, time_t end)
{
    char *str_query, *iso_start, *iso_end;

    iso_start = isodate_from_time_t (start);
    if (!iso_start)
        return;
                                                                               
    iso_end = isodate_from_time_t (end);
    if (!iso_end) {
        g_free (iso_start);
        return;
    }

    str_query = g_strdup_printf ("(has-alarms-in-range? (make-time \"%s\") (make-time \"%s\"))",
                     iso_start, iso_end);
    g_free (iso_start);
    g_free (iso_end);

    /* create the live query */
    if (ca->query) {
        g_object_unref (ca->query);
        ca->query = NULL;
    }

    /* FIXME: handle errors */
    if (!e_cal_get_query (ca->client, str_query, &ca->query, NULL)) {
        g_warning (G_STRLOC ": Could not get query for client");
    } else {
        g_signal_connect (G_OBJECT (ca->query), "objects_added",
                  G_CALLBACK (query_objects_changed_cb), ca);
        g_signal_connect (G_OBJECT (ca->query), "objects_modified",
                  G_CALLBACK (query_objects_changed_cb), ca);
        g_signal_connect (G_OBJECT (ca->query), "objects_removed",
                  G_CALLBACK (query_objects_removed_cb), ca);

        e_cal_view_start (ca->query);
    }

    g_free (str_query);
}

/* Loads today's remaining alarms for a client */
static void
load_alarms_for_today (ClientAlarms *ca)
{
    time_t now, from, day_end;
    icaltimezone *zone;

    now = time (NULL);

    /* Make sure we don't miss some events from the last notification.
     * We add 1 to the saved_notification_time to make the time ranges
     * half-open; we do not want to display the "last" displayed alarm
     * twice, once when it occurs and once when the alarm daemon restarts.
     */
    from = MIN (config_data_get_last_notification_time () + 1, now);
    zone = config_data_get_timezone ();

    g_message ("Loading alarms for today");
    day_end = time_day_end_with_zone (now, zone);
    load_alarms (ca, from, day_end);
}

/* Called when a calendar client finished loading; we load its alarms */
static void
cal_opened_cb (ECal *client, ECalendarStatus status, gpointer data)
{
    ClientAlarms *ca;

    ca = data;

    if (status != E_CALENDAR_STATUS_OK)
        return;

    load_alarms_for_today (ca);
}

/* Looks up a component's queued alarm structure in a client alarms structure */
static CompQueuedAlarms *
lookup_comp_queued_alarms (ClientAlarms *ca, const char *uid)
{
    return g_hash_table_lookup (ca->uid_alarms_hash, uid);
}

static void
remove_alarms (CompQueuedAlarms *cqa, gboolean free_object)
{
    GSList *l;

    for (l = cqa->queued_alarms; l;) {
        QueuedAlarm *qa;

        qa = l->data;

        /* Get the next element here because the list element will go
         * away in remove_queued_alarm().  The qa will be freed there as
         * well.
         */
        l = l->next;

        alarm_remove (qa->alarm_id);
        remove_queued_alarm (cqa, qa->alarm_id, free_object, FALSE);
    }

}

/* Removes a component an its alarms */
static void
remove_comp (ClientAlarms *ca, const char *uid)
{
    CompQueuedAlarms *cqa;

    cqa = lookup_comp_queued_alarms (ca, uid);
    if (!cqa)
        return;

    /* If a component is present, then it means we must have alarms queued
     * for it.
     */
    g_assert (cqa->queued_alarms != NULL);

    remove_alarms (cqa, TRUE);

    /* The list should be empty now, and thus the queued component alarms
     * structure should have been freed and removed from the hash table.
     */
    g_assert (lookup_comp_queued_alarms (ca, uid) == NULL);
}

/* Called when a calendar component changes; we must reload its corresponding
 * alarms.
 */
static void
query_objects_changed_cb (ECal *client, GList *objects, gpointer data)
{
    ClientAlarms *ca;
    time_t from, day_end;
    ECalComponentAlarms *alarms;
    gboolean found;
    icaltimezone *zone;
    CompQueuedAlarms *cqa;
    GList *l;

    ca = data;

    from = config_data_get_last_notification_time ();
    if (from == -1)
        from = time (NULL);
    else
        from += 1; /* we add 1 to make sure the alarm is not displayed twice */

    zone = config_data_get_timezone ();

    day_end = time_day_end_with_zone (time (NULL), zone);
    g_message ("Query response for alarms");
    for (l = objects; l != NULL; l = l->next) {
        const char *uid;
        GSList *sl;

        uid = icalcomponent_get_uid (l->data);
        found = e_cal_get_alarms_for_object (ca->client, uid, from, day_end, &alarms);

        if (!found) {
            g_message ("No alarms found on object");
            remove_comp (ca, uid);
            continue;
        }

        cqa = lookup_comp_queued_alarms (ca, uid);
        if (!cqa) {
            g_message ("No currently queue alarms");
            add_component_alarms (ca, alarms);
            continue;
        }

        g_message ("Already existing alarms");
        /* if the alarms or the alarms list is empty, just remove it */
        if (alarms == NULL || alarms->alarms == NULL) {
            if (alarms)
                e_cal_component_alarms_free (alarms);
            continue;
        }

        /* if already in the list, just update it */
        remove_alarms (cqa, FALSE);
        cqa->alarms = alarms;
        cqa->queued_alarms = NULL;
        
        /* add the new alarms */
        for (sl = cqa->alarms->alarms; sl; sl = sl->next) {
            ECalComponentAlarmInstance *instance;
            gpointer alarm_id;
            QueuedAlarm *qa;

            instance = sl->data;

            alarm_id = alarm_add (instance->trigger, alarm_trigger_cb, cqa, NULL);
            if (!alarm_id) {
                g_message (G_STRLOC ": Could not schedule a trigger for "
                       "%ld, discarding...", (long) instance->trigger);
                continue;
            }

            qa = g_new (QueuedAlarm, 1);
            qa->alarm_id = alarm_id;
            qa->instance = instance;
            qa->snooze = FALSE;
            
            cqa->queued_alarms = g_slist_prepend (cqa->queued_alarms, qa);
        }
        
        cqa->queued_alarms = g_slist_reverse (cqa->queued_alarms);
    }
}

/* Called when a calendar component is removed; we must delete its corresponding
 * alarms.
 */
static void
query_objects_removed_cb (ECal *client, GList *objects, gpointer data)
{
    ClientAlarms *ca;
    GList *l;

    ca = data;

    for (l = objects; l != NULL; l = l->next)
        remove_comp (ca, l->data);
}



/* Notification functions */

/* Creates a snooze alarm based on an existing one.  The snooze offset is
 * compued with respect to the current time.
 */
static void
create_snooze (CompQueuedAlarms *cqa, gpointer alarm_id, int snooze_mins)
{
    QueuedAlarm *orig_qa;
    time_t t;
    gpointer new_id;

    orig_qa = lookup_queued_alarm (cqa, alarm_id);
    if (!orig_qa)
        return;

    t = time (NULL);
    t += snooze_mins * 60;

    new_id = alarm_add (t, alarm_trigger_cb, cqa, NULL);
    if (!new_id) {
        g_message ("create_snooze(): Could not schedule a trigger for "
               "%ld, discarding...", (long) t);
        return;
    }

    orig_qa->instance->trigger = t;
    orig_qa->alarm_id = new_id;
    orig_qa->snooze = TRUE;
}

/* Launches a component editor for a component */
static void
edit_component (ECal *client, ECalComponent *comp)
{
    const char *uid;
    const char *uri;
    ECalSourceType source_type;
    CORBA_Environment ev;
    GNOME_Evolution_Calendar_CompEditorFactory factory;
    GNOME_Evolution_Calendar_CompEditorFactory_CompEditorMode corba_type;

    e_cal_component_get_uid (comp, &uid);

    uri = e_cal_get_uri (client);
    source_type = e_cal_get_source_type (client);

    /* Get the factory */
    CORBA_exception_init (&ev);
    factory = bonobo_activation_activate_from_id ("OAFIID:GNOME_Evolution_Calendar_CompEditorFactory:" BASE_VERSION,
                              0, NULL, &ev);

    if (BONOBO_EX (&ev)) {
        g_message (G_STRLOC ": Could not activate the component editor factory");
        CORBA_exception_free (&ev);
        return;
    }

    /* Edit the component */
    switch (source_type) {
    case E_CAL_SOURCE_TYPE_TODO:
        corba_type = GNOME_Evolution_Calendar_CompEditorFactory_EDITOR_MODE_TODO;
        break;
    default:
        corba_type = GNOME_Evolution_Calendar_CompEditorFactory_EDITOR_MODE_EVENT;      
    }
    
    GNOME_Evolution_Calendar_CompEditorFactory_editExisting (factory, uri, (char *) uid, corba_type, &ev);

    if (BONOBO_EX (&ev))
        g_message (G_STRLOC ": Exception while editing the component");

    CORBA_exception_free (&ev);

    /* Get rid of the factory */
    bonobo_object_release_unref (factory, NULL);
}

typedef struct {
    char *message;
    gboolean blink_state;
    gint blink_id;
    time_t trigger;
    CompQueuedAlarms *cqa;
    gpointer alarm_id;
    ECalComponent *comp;
    ECal *client;
    ECalView *query;
    GtkWidget *tray_icon;
    GtkWidget *image;
    GtkWidget *alarm_dialog;
} TrayIconData;

static void
on_dialog_objs_removed_cb (ECal *client, GList *objects, gpointer data)
{
    const char *our_uid;
    GList *l;
    TrayIconData *tray_data = data;

    e_cal_component_get_uid (tray_data->comp, &our_uid);
    g_return_if_fail (our_uid && *our_uid);

    for (l = objects; l != NULL; l = l->next) {
        const char *uid = l->data;

        if (!uid)
            continue;

        if (!strcmp (uid, our_uid)) {
            if (tray_data->alarm_dialog)
                alarm_notify_dialog_disable_buttons (tray_data->alarm_dialog);
            tray_data->cqa = NULL;
            tray_data->alarm_id = NULL;

            gtk_widget_destroy (tray_data->tray_icon);
        }
    }
}

/* Callback used from the alarm notify dialog */
static void
notify_dialog_cb (AlarmNotifyResult result, int snooze_mins, gpointer data)
{
    TrayIconData *tray_data = data;

    g_signal_handlers_disconnect_matched (tray_data->query, G_SIGNAL_MATCH_FUNC,
                          0, 0, NULL, on_dialog_objs_removed_cb, NULL);

    switch (result) {
    case ALARM_NOTIFY_SNOOZE:
        create_snooze (tray_data->cqa, tray_data->alarm_id, snooze_mins);
        tray_data->cqa = NULL;
        return;

    case ALARM_NOTIFY_EDIT:
        edit_component (tray_data->client, tray_data->comp);
        break;

    case ALARM_NOTIFY_CLOSE:
        /* Do nothing */
        break;

    default:
        g_assert_not_reached ();
    }

    tray_data->alarm_dialog = NULL;
    gtk_widget_destroy (tray_data->tray_icon);
}

static gint
tray_icon_destroyed_cb (GtkWidget *tray, gpointer user_data)
{
    TrayIconData *tray_data = user_data;

    g_signal_handlers_disconnect_matched (tray_data->query, G_SIGNAL_MATCH_FUNC,
                          0, 0, NULL, on_dialog_objs_removed_cb, NULL);

    if (tray_data->cqa != NULL)
        remove_queued_alarm (tray_data->cqa, tray_data->alarm_id, TRUE, TRUE);

    if (tray_data->message != NULL) {
        g_free (tray_data->message);
        tray_data->message = NULL;
    }

    if (tray_data->blink_id)
        g_source_remove (tray_data->blink_id);

    g_object_unref (tray_data->comp);
    g_object_unref (tray_data->client);
    g_object_unref (tray_data->query);

    tray_icons_list = g_list_remove (tray_icons_list, tray_data);
    g_free (tray_data);

    return TRUE;
}

/* Callbacks.  */
static void
add_popup_menu_item (GtkMenu *menu, const char *label, const char *pixmap,
             GCallback callback, gpointer user_data)
{
    GtkWidget *item, *image;

    if (pixmap) {
        item = gtk_image_menu_item_new_with_label (label);

        /* load the image */
        if (g_file_test (pixmap, G_FILE_TEST_EXISTS))
            image = gtk_image_new_from_file (pixmap);
        else
            image = gtk_image_new_from_stock (pixmap, GTK_ICON_SIZE_MENU);

        if (image) {
            gtk_widget_show (image);
            gtk_image_menu_item_set_image (GTK_IMAGE_MENU_ITEM (item), image);
        }
    } else {
        item = gtk_menu_item_new_with_label (label);
    }

    if (callback)
        g_signal_connect (G_OBJECT (item), "activate", callback, user_data);

    gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
    gtk_widget_show (item);
}

static gboolean
open_alarm_dialog (TrayIconData *tray_data)
{
    QueuedAlarm *qa;

    if (tray_data->alarm_dialog != NULL)
        return FALSE;

    qa = lookup_queued_alarm (tray_data->cqa, tray_data->alarm_id);
    if (qa) {
        gtk_widget_hide (tray_data->tray_icon);
        tray_data->alarm_dialog = alarm_notify_dialog (
            tray_data->trigger,
            qa->instance->occur_start,
            qa->instance->occur_end,
            e_cal_component_get_vtype (tray_data->comp),
            tray_data->message,
            notify_dialog_cb, tray_data);
    }

    return TRUE;
}

static void
popup_dismiss_cb (GtkWidget *widget, TrayIconData *tray_data)
{
    gtk_widget_destroy (tray_data->tray_icon);
}

static void
popup_dismiss_all_cb (GtkWidget *widget, TrayIconData *tray_data)
{
    while (tray_icons_list != NULL) {
        TrayIconData *tray_data = tray_icons_list->data;

        gtk_widget_destroy (tray_data->tray_icon);

        tray_icons_list = g_list_remove (tray_icons_list, tray_icons_list);
    }
}

static void
popup_open_cb (GtkWidget *widget, TrayIconData *tray_data)
{
    open_alarm_dialog (tray_data);
}

static gint
tray_icon_clicked_cb (GtkWidget *widget, GdkEventButton *event, gpointer user_data)
{
    TrayIconData *tray_data = user_data;

    if (event->type == GDK_BUTTON_PRESS) {
        if (event->button == 1) {
            return open_alarm_dialog (tray_data);
        } else if (event->button == 3) {
            GtkWidget *menu;

            /* display popup menu */
            menu = gtk_menu_new ();
            add_popup_menu_item (GTK_MENU (menu), _("Open"), GTK_STOCK_OPEN,
                         G_CALLBACK (popup_open_cb), tray_data);
            add_popup_menu_item (GTK_MENU (menu), _("Dismiss"), NULL,
                         G_CALLBACK (popup_dismiss_cb), tray_data);
            add_popup_menu_item (GTK_MENU (menu), _("Dismiss All"), NULL,
                         G_CALLBACK (popup_dismiss_all_cb), tray_data);
            gtk_menu_popup (GTK_MENU (menu), NULL, NULL, NULL, NULL, event->button, event->time);

            return TRUE;
        }
    }

    return FALSE;
}

static gboolean
tray_icon_blink_cb (gpointer data)
{
    TrayIconData *tray_data = data;
    GdkPixbuf *pixbuf;

    tray_data->blink_state = tray_data->blink_state == TRUE ? FALSE : TRUE;
    pixbuf = e_icon_factory_get_icon  (tray_data->blink_state == TRUE ?
                       "stock_appointment-reminder-excl" :
                       "stock_appointment-reminder",
                       E_ICON_SIZE_LARGE_TOOLBAR);

    gtk_image_set_from_pixbuf (GTK_IMAGE (tray_data->image), pixbuf);
    g_object_unref (pixbuf);

    return TRUE;
}

/* Performs notification of a display alarm */
static void
display_notification (time_t trigger, CompQueuedAlarms *cqa,
              gpointer alarm_id, gboolean use_description)
{
    QueuedAlarm *qa;
    ECalComponent *comp;
    const char *message;
    ECalComponentAlarm *alarm;
    GtkWidget *tray_icon, *image, *ebox;
    GtkTooltips *tooltips;
    TrayIconData *tray_data;
    ECalComponentText text;
    char *str, *start_str, *end_str, *alarm_str;
    icaltimezone *current_zone;
    GdkPixbuf *pixbuf;

    comp = cqa->alarms->comp;
    qa = lookup_queued_alarm (cqa, alarm_id);
    if (!qa)
        return;
    
    /* get a sensible description for the event */
    alarm = e_cal_component_get_alarm (comp, qa->instance->auid);
    g_assert (alarm != NULL);

    e_cal_component_alarm_get_description (alarm, &text);
    e_cal_component_alarm_free (alarm);

    if (text.value)
        message = text.value;
    else {
        e_cal_component_get_summary (comp, &text); 
        if (text.value)
            message = text.value;
        else
            message = _("No description available.");
    }

    /* create the tray icon */
    tooltips = gtk_tooltips_new ();

    tray_icon = egg_tray_icon_new (qa->instance->auid);
    pixbuf = e_icon_factory_get_icon  ("stock_appointment-reminder", E_ICON_SIZE_LARGE_TOOLBAR);
    image = gtk_image_new_from_pixbuf (pixbuf);
    gdk_pixbuf_unref (pixbuf);
    ebox = gtk_event_box_new ();

    gtk_widget_show (image);
    gtk_widget_show (ebox);

    current_zone = config_data_get_timezone ();
    alarm_str = timet_to_str_with_zone (trigger, current_zone);
    start_str = timet_to_str_with_zone (qa->instance->occur_start, current_zone);
    end_str = timet_to_str_with_zone (qa->instance->occur_end, current_zone);
    str = g_strdup_printf (_("Alarm on %s\n%s\nStarting at %s\nEnding at %s"),
                   alarm_str, message, start_str, end_str);
    gtk_tooltips_set_tip (GTK_TOOLTIPS (tooltips), ebox, str, str);
    g_free (start_str);
    g_free (end_str);
    g_free (alarm_str);
    g_free (str);
    
    g_object_set_data (G_OBJECT (tray_icon), "image", image);
    g_object_set_data (G_OBJECT (tray_icon), "available", GINT_TO_POINTER (1));

    gtk_container_add (GTK_CONTAINER (ebox), image);
    gtk_container_add (GTK_CONTAINER (tray_icon), ebox);

    /* create the private structure */
    tray_data = g_new0 (TrayIconData, 1);
    tray_data->message = g_strdup (message);
    tray_data->trigger = trigger;
    tray_data->cqa = cqa;
    tray_data->alarm_id = alarm_id;
    tray_data->comp = e_cal_component_clone (comp);
    tray_data->client = cqa->parent_client->client;
    tray_data->query = g_object_ref (cqa->parent_client->query);
    tray_data->image = image;
    tray_data->blink_state = FALSE;
    g_object_ref (tray_data->client);
    tray_data->tray_icon = tray_icon;

    tray_icons_list = g_list_prepend (tray_icons_list, tray_data);

    g_signal_connect (G_OBJECT (tray_icon), "destroy",
              G_CALLBACK (tray_icon_destroyed_cb), tray_data);
    g_signal_connect (G_OBJECT (ebox), "button_press_event",
              G_CALLBACK (tray_icon_clicked_cb), tray_data);
    g_signal_connect (G_OBJECT (tray_data->query), "objects_removed",
              G_CALLBACK (on_dialog_objs_removed_cb), tray_data);

    if (!config_data_get_notify_with_tray ()) {
        tray_data->blink_id = -1;
        open_alarm_dialog (tray_data);
    } else {
        tray_data->blink_id = g_timeout_add (500, tray_icon_blink_cb, tray_data);
        gtk_widget_show (tray_icon);
    }
}

/* Performs notification of an audio alarm */
static void
audio_notification (time_t trigger, CompQueuedAlarms *cqa,
            gpointer alarm_id)
{
    QueuedAlarm *qa;
    ECalComponent *comp;
    ECalComponentAlarm *alarm;
    icalattach *attach;
    int flag = 0;

    comp = cqa->alarms->comp;
    qa = lookup_queued_alarm (cqa, alarm_id);
    if (!qa)
        return;

    alarm = e_cal_component_get_alarm (comp, qa->instance->auid);
    g_assert (alarm != NULL);

    e_cal_component_alarm_get_attach (alarm, &attach);
    e_cal_component_alarm_free (alarm);

    if (attach && icalattach_get_is_url (attach)) {
        const char *url;

        url = icalattach_get_url (attach);

        if (url && *url && g_file_test (url, G_FILE_TEST_EXISTS)) {
            flag = 1;
            gnome_sound_play (url); /* this sucks */
        }
    }

    if (!flag)
        gdk_beep ();

    if (attach)
        icalattach_unref (attach);

    /* We present a notification message in addition to playing the sound */
    display_notification (trigger, cqa, alarm_id, FALSE);
}

/* Performs notification of a mail alarm */
static void
mail_notification (time_t trigger, CompQueuedAlarms *cqa, gpointer alarm_id)
{
    GtkWidget *dialog;
    GtkWidget *label;

    /* FIXME */

    display_notification (trigger, cqa, alarm_id, FALSE);

    dialog = gtk_dialog_new_with_buttons (_("Warning"),
                          NULL, 0,
                          GTK_STOCK_OK, GTK_RESPONSE_CANCEL,
                          NULL);
    label = gtk_label_new (_("Evolution does not support calendar reminders with\n"
                 "email notifications yet, but this reminder was\n"
                 "configured to send an email.  Evolution will display\n"
                 "a normal reminder dialog box instead."));
    gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dialog)->vbox), label, TRUE, TRUE, 4);

    gtk_dialog_run (GTK_DIALOG (dialog));
}

/* Performs notification of a procedure alarm */
static gboolean
procedure_notification_dialog (const char *cmd, const char *url) 
{
    GtkWidget *dialog, *label, *checkbox;
    char *str;
    int btn;
    
    if (config_data_is_blessed_program (url))
        return TRUE;
    
    dialog = gtk_dialog_new_with_buttons (_("Warning"),
                          NULL, 0,
                          GTK_STOCK_NO, GTK_RESPONSE_CANCEL,
                          GTK_STOCK_YES, GTK_RESPONSE_OK,
                          NULL);

    str = g_strdup_printf (_("An Evolution Calendar reminder is about to trigger. "
                 "This reminder is configured to run the following program:\n\n"
                 "        %s\n\n"
                 "Are you sure you want to run this program?"),
                   cmd);
    label = gtk_label_new (str);
    gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
    gtk_label_set_justify (GTK_LABEL (label), GTK_JUSTIFY_LEFT);
    gtk_widget_show (label);
    gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dialog)->vbox),
                label, TRUE, TRUE, 4);
    g_free (str);

    checkbox = gtk_check_button_new_with_label
        (_("Do not ask me about this program again."));
    gtk_widget_show (checkbox);
    gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dialog)->vbox), 
                checkbox, TRUE, TRUE, 4);

    /* Run the dialog */
    btn = gtk_dialog_run (GTK_DIALOG (dialog));
    if (btn == GTK_RESPONSE_OK && gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (checkbox)))
        config_data_save_blessed_program (url);
    gtk_widget_destroy (dialog);

    return (btn == GTK_RESPONSE_OK);
}

static void
procedure_notification (time_t trigger, CompQueuedAlarms *cqa, gpointer alarm_id)
{
    QueuedAlarm *qa;
    ECalComponent *comp;
    ECalComponentAlarm *alarm;
    ECalComponentText description;
    icalattach *attach;
    const char *url;
    char *cmd;
    int result;

    comp = cqa->alarms->comp;
    qa = lookup_queued_alarm (cqa, alarm_id);
    if (!qa)
        return;

    alarm = e_cal_component_get_alarm (comp, qa->instance->auid);
    g_assert (alarm != NULL);

    e_cal_component_alarm_get_attach (alarm, &attach);
    e_cal_component_alarm_get_description (alarm, &description);
    e_cal_component_alarm_free (alarm);

    /* If the alarm has no attachment, simply display a notification dialog. */
    if (!attach)
        goto fallback;

    if (!icalattach_get_is_url (attach)) {
        icalattach_unref (attach);
        goto fallback;
    }

    url = icalattach_get_url (attach);
    g_assert (url != NULL);

    /* Ask for confirmation before executing the stuff */
    if (description.value)
        cmd = g_strconcat (url, " ", description.value, NULL);
    else
        cmd = (char *) url;

    result = 0;
    if (procedure_notification_dialog (cmd, url))
        result = gnome_execute_shell (NULL, cmd);
    
    if (cmd != (char *) url)
        g_free (cmd);

    icalattach_unref (attach);

    /* Fall back to display notification if we got an error */
    if (result < 0)
        goto fallback;

    remove_queued_alarm (cqa, alarm_id, TRUE, TRUE);
    return;

 fallback:

    display_notification (trigger, cqa, alarm_id, FALSE);
}



/**
 * alarm_queue_init:
 *
 * Initializes the alarm queueing system.  This should be called near the
 * beginning of the program.
 **/
void
alarm_queue_init (void)
{
    g_return_if_fail (alarm_queue_inited == FALSE);

    client_alarms_hash = g_hash_table_new (g_direct_hash, g_direct_equal);
    queue_midnight_refresh ();

    saved_notification_time = config_data_get_last_notification_time ();
    if (saved_notification_time == -1) {
        saved_notification_time = time (NULL);
        config_data_set_last_notification_time (saved_notification_time);
    }

    alarm_queue_inited = TRUE;
}

static void
free_client_alarms_cb (gpointer key, gpointer value, gpointer user_data)
{
    ClientAlarms *ca = value;

    if (ca) {
        g_object_unref (ca->client);
        g_free (ca);
    }
}

/**
 * alarm_queue_done:
 *
 * Shuts down the alarm queueing system.  This should be called near the end
 * of the program.  All the monitored calendar clients should already have been
 * unregistered with alarm_queue_remove_client().
 **/
void
alarm_queue_done (void)
{
    g_return_if_fail (alarm_queue_inited);

    /* All clients must be unregistered by now */
    g_return_if_fail (g_hash_table_size (client_alarms_hash) == 0);

    g_hash_table_foreach (client_alarms_hash, (GHFunc) free_client_alarms_cb, NULL);
    g_hash_table_destroy (client_alarms_hash);
    client_alarms_hash = NULL;

    g_assert (midnight_refresh_id != NULL);
    alarm_remove (midnight_refresh_id);
    midnight_refresh_id = NULL;

    alarm_queue_inited = FALSE;
}

/**
 * alarm_queue_add_client:
 * @client: A calendar client.
 *
 * Adds a calendar client to the alarm queueing system.  Alarm trigger
 * notifications will be presented at the appropriate times.  The client should
 * be removed with alarm_queue_remove_client() when receiving notifications
 * from it is no longer desired.
 *
 * A client can be added any number of times to the alarm queueing system,
 * but any single alarm trigger will only be presented once for a particular
 * client.  The client must still be removed the same number of times from the
 * queueing system when it is no longer wanted.
 **/
void
alarm_queue_add_client (ECal *client)
{
    ClientAlarms *ca;

    g_return_if_fail (alarm_queue_inited);
    g_return_if_fail (client != NULL);
    g_return_if_fail (E_IS_CAL (client));

    ca = lookup_client (client);
    if (ca) {
        return;
    }

    ca = g_new (ClientAlarms, 1);

    ca->client = client;
    ca->query = NULL;
    g_object_ref (ca->client);

    g_hash_table_insert (client_alarms_hash, client, ca);

    ca->uid_alarms_hash = g_hash_table_new (g_str_hash, g_str_equal);

    if (e_cal_get_load_state (client) == E_CAL_LOAD_LOADED) {
        load_alarms_for_today (ca);
    } else {
        g_signal_connect (client, "cal_opened",
                  G_CALLBACK (cal_opened_cb),
                  ca);
    }
}

/* Called from g_hash_table_foreach(); adds a component UID to a list */
static void
add_uid_cb (gpointer key, gpointer value, gpointer data)
{
    GSList **uids;
    const char *uid;

    uids = data;
    uid = key;

    *uids = g_slist_prepend (*uids, (char *) uid);
}

/* Removes all the alarms queued for a particular calendar client */
static void
remove_client_alarms (ClientAlarms *ca)
{
    GSList *uids;
    GSList *l;

    /* First we build a list of UIDs so that we can remove them one by one */

    uids = NULL;
    g_hash_table_foreach (ca->uid_alarms_hash, add_uid_cb, &uids);

    for (l = uids; l; l = l->next) {
        const char *uid;

        uid = l->data;

        remove_comp (ca, uid);
    }

    g_slist_free (uids);

    /* The hash table should be empty now */

    g_assert (g_hash_table_size (ca->uid_alarms_hash) == 0);
}

/**
 * alarm_queue_remove_client:
 * @client: A calendar client.
 *
 * Removes a calendar client from the alarm queueing system.
 **/
void
alarm_queue_remove_client (ECal *client)
{
    ClientAlarms *ca;

    g_return_if_fail (alarm_queue_inited);
    g_return_if_fail (client != NULL);
    g_return_if_fail (E_IS_CAL (client));

    ca = lookup_client (client);
    g_return_if_fail (ca != NULL);

    remove_client_alarms (ca);

    /* Clean up */

    g_signal_handlers_disconnect_matched (ca->client, G_SIGNAL_MATCH_DATA,
                          0, 0, NULL, NULL, ca);

    g_object_unref (ca->query);
    ca->query = NULL;
    g_object_unref (ca->client);
    ca->client = NULL;

    g_hash_table_destroy (ca->uid_alarms_hash);
    ca->uid_alarms_hash = NULL;

    g_free (ca);

    g_hash_table_remove (client_alarms_hash, client);
}