path: root/calendar/gui/e-tasks.c

/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
/* e-tasks.c
 *
 * Copyright (C) 2001-2003  Ximian, Inc.
 *
 * 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.
 *
 * Authors: Federico Mena Quintero <federico@ximian.com>
 *      Damon Chaplin <damon@ximian.com>
 *          Rodrigo Moya <rodrigo@ximian.com>
 */

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

#include <gnome.h>
#include <libgnomevfs/gnome-vfs-ops.h>
#include <libedataserver/e-time-utils.h>
#include <table/e-table-scrolled.h>
#include <widgets/menus/gal-view-instance.h>
#include <widgets/menus/gal-view-factory-etable.h>
#include <widgets/menus/gal-view-etable.h>

#include "e-util/e-error.h"
#include "e-util/e-categories-config.h"
#include "e-util/e-config-listener.h"
#include "e-util/e-util-private.h"
#include "shell/e-user-creatable-items-handler.h"
#include <libedataserver/e-url.h>
#include <libedataserver/e-categories.h>
#include <libecal/e-cal-time-util.h>
#include "widgets/menus/gal-view-menus.h"
#include "dialogs/delete-error.h"
#include "dialogs/task-editor.h"
#include "e-calendar-marshal.h"
#include "cal-search-bar.h"
#include "calendar-config.h"
#include "calendar-component.h"
#include "comp-util.h"
#include "e-calendar-table-config.h"
#include "misc.h"
#include "tasks-component.h"
#include "e-cal-component-preview.h"
#include "e-tasks.h"
#include "common/authentication.h"
#include "e-cal-menu.h"
#include "e-cal-model-tasks.h"


/* Private part of the GnomeCalendar structure */
struct _ETasksPrivate {
    /* The task lists for display */
    GHashTable *clients;
    GList *clients_list;
    ECal *default_client;

    ECalView *query;
    
    EConfigListener *config_listener;

    /* The ECalendarTable showing the tasks. */
    GtkWidget   *tasks_view;
    ECalendarTableConfig *tasks_view_config;
    
    /* Calendar search bar for tasks */
    GtkWidget *search_bar;

    /* Tasks menu */
    ECalMenu *tasks_menu;

    /* Paned widget */
    GtkWidget *paned;

    /* The preview */
    GtkWidget *preview;
    
    gchar *current_uid;
    char *sexp;
    guint update_timeout;
    
    /* View instance and the view menus handler */
    GalViewInstance *view_instance;
    GalViewMenus *view_menus;

    GList *notifications;
};

static void setup_widgets (ETasks *tasks);
static void e_tasks_destroy (GtkObject *object);
static void update_view (ETasks *tasks);

static void config_categories_changed_cb (EConfigListener *config_listener, const char *key, gpointer user_data);
static void backend_error_cb (ECal *client, const char *message, gpointer data);

/* Signal IDs */
enum {
    SELECTION_CHANGED,
    SOURCE_ADDED,
    SOURCE_REMOVED,
    LAST_SIGNAL
};

enum DndTargetType {
    TARGET_VCALENDAR
};

static GtkTargetEntry list_drag_types[] = {
    { "text/calendar",                0, TARGET_VCALENDAR },
    { "text/x-calendar",              0, TARGET_VCALENDAR }
};
static const int num_list_drag_types = sizeof (list_drag_types) / sizeof (list_drag_types[0]);

static guint e_tasks_signals[LAST_SIGNAL] = { 0 };

G_DEFINE_TYPE (ETasks, e_tasks, GTK_TYPE_TABLE)

/* Callback used when the cursor changes in the table */
static void
table_cursor_change_cb (ETable *etable, int row, gpointer data)
{
    ETasks *tasks;
    ETasksPrivate *priv;
    ECalModel *model;
    ECalModelComponent *comp_data;
    ECalComponent *comp;
    const char *uid;

    int n_selected;

    tasks = E_TASKS (data);
    priv = tasks->priv;

    n_selected = e_table_selected_count (etable);
    
    /* update the HTML widget */
    if (n_selected != 1) {
        e_cal_component_preview_clear (E_CAL_COMPONENT_PREVIEW (priv->preview));

        return;
    }
    
    model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
    
    comp_data = e_cal_model_get_component_at (model, e_table_get_cursor_row (etable));
    comp = e_cal_component_new ();
    e_cal_component_set_icalcomponent (comp, icalcomponent_new_clone (comp_data->icalcomp));

    e_cal_component_preview_display (E_CAL_COMPONENT_PREVIEW (priv->preview), comp_data->client, comp);
    
    e_cal_component_get_uid (comp, &uid);
    if (priv->current_uid)
        g_free (priv->current_uid);
    priv->current_uid = g_strdup (uid);
    
    g_object_unref (comp);
}

ECalMenu *
e_tasks_get_tasks_menu (ETasks *tasks)
{
        g_return_val_if_fail (E_IS_TASKS (tasks), NULL);

        return tasks->priv->tasks_menu;
}


/* Callback used when the selection changes in the table. */
static void
table_selection_change_cb (ETable *etable, gpointer data)
{
    ETasks *tasks;
    int n_selected;

    tasks = E_TASKS (data);

    n_selected = e_table_selected_count (etable);
    gtk_signal_emit (GTK_OBJECT (tasks), e_tasks_signals[SELECTION_CHANGED],
             n_selected);
}

static void
user_created_cb (GtkWidget *view, ETasks *tasks)
{
    ETasksPrivate *priv;    
    ECal *ecal;
    ECalModel *model;
    
    priv = tasks->priv;

    model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
    ecal = e_cal_model_get_default_client (model);

    e_tasks_add_todo_source (tasks, e_cal_get_source (ecal));
}

/* Callback used when the sexp in the search bar changes */
static void
search_bar_sexp_changed_cb (CalSearchBar *cal_search, const char *sexp, gpointer data)
{
    ETasks *tasks;
    ETasksPrivate *priv;

    tasks = E_TASKS (data);
    priv = tasks->priv;

    if (priv->sexp)
        g_free (priv->sexp);
    
    priv->sexp = g_strdup (sexp);

    update_view (tasks);
}

/* Callback used when the selected category in the search bar changes */
static void
search_bar_category_changed_cb (CalSearchBar *cal_search, const char *category, gpointer data)
{
    ETasks *tasks;
    ETasksPrivate *priv;
    ECalModel *model;

    tasks = E_TASKS (data);
    priv = tasks->priv;

    model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
    e_cal_model_set_default_category (model, category);
}

static gboolean
vpaned_resized_cb (GtkWidget *widget, GdkEventButton *event, ETasks *tasks)
{
    calendar_config_set_task_vpane_pos (gtk_paned_get_position (GTK_PANED (widget)));

    return FALSE;
}

static void
set_timezone (ETasks *tasks) 
{
    ETasksPrivate *priv;
    icaltimezone *zone;
    GList *l;
    
    priv = tasks->priv;
    
    zone = calendar_config_get_icaltimezone ();
    for (l = priv->clients_list; l != NULL; l = l->next) {
        ECal *client = l->data;
        /* FIXME Error checking */
        e_cal_set_default_timezone (client, zone, NULL);
    }

    if (priv->default_client) 
        /* FIXME Error checking */
        e_cal_set_default_timezone (priv->default_client, zone, NULL);

    if (priv->preview)
        e_cal_component_preview_set_default_timezone (E_CAL_COMPONENT_PREVIEW (priv->preview), zone);
}

static void
timezone_changed_cb (GConfClient *client, guint id, GConfEntry *entry, gpointer data)
{
    ETasks *tasks = data;
    
    set_timezone (tasks);
}

static void
update_view (ETasks *tasks)
{
    ETasksPrivate *priv;
    ECalModel *model;
    char *real_sexp = NULL;
    char *new_sexp = NULL;
    
    priv = tasks->priv;

    model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
        
    if ((new_sexp = calendar_config_get_hide_completed_tasks_sexp (FALSE)) != NULL) {
        real_sexp = g_strdup_printf ("(and %s %s)", new_sexp, priv->sexp);
        e_cal_model_set_search_query (model, real_sexp);
        g_free (new_sexp);
        g_free (real_sexp);
    } else
        e_cal_model_set_search_query (model, priv->sexp);

    e_cal_component_preview_clear (E_CAL_COMPONENT_PREVIEW (priv->preview));
}

static void
process_completed_tasks (ETasks *tasks, gboolean config_changed)
{
    ETasksPrivate *priv;

    g_return_if_fail (tasks != NULL);
    g_return_if_fail (E_IS_TASKS (tasks));

    priv = tasks->priv;

    e_calendar_table_process_completed_tasks (e_tasks_get_calendar_table (tasks), priv->clients_list, config_changed);
}

static gboolean
update_view_cb (ETasks *tasks)
{   
    ECalModel *model;

    model = e_calendar_table_get_model (E_CALENDAR_TABLE (tasks->priv->tasks_view));

    process_completed_tasks (tasks, FALSE);
    e_cal_model_tasks_update_due_tasks (E_CAL_MODEL_TASKS (model));

    return TRUE;
}

static void
config_hide_completed_tasks_changed_cb (GConfClient *client, guint id, GConfEntry *entry, gpointer data)
{
    process_completed_tasks (data, TRUE);
}

static void
model_row_changed_cb (ETableModel *etm, int row, gpointer data)
{
    ETasks *tasks;
    ETasksPrivate *priv;
    ECalModelComponent *comp_data;

    tasks = E_TASKS (data);
    priv = tasks->priv;

    if (priv->current_uid) {
        const char *uid;

        comp_data = e_cal_model_get_component_at (E_CAL_MODEL (etm), row);
        if (comp_data) {
            uid = icalcomponent_get_uid (comp_data->icalcomp);
            if (!strcmp (uid ? uid : "", priv->current_uid)) {
                ETable *etable;

                etable = e_table_scrolled_get_table (
                    E_TABLE_SCROLLED (E_CALENDAR_TABLE (priv->tasks_view)->etable));
                table_cursor_change_cb (etable, 0, tasks);
            }
        }
    }
}

static void
view_progress_cb (ECalModel *model, const char *message, int percent, ECalSourceType type, ETasks *tasks)
{
    e_calendar_table_set_status_message (E_CALENDAR_TABLE (e_tasks_get_calendar_table (tasks)), 
            message, percent);
}

static void
view_done_cb (ECalModel *model, ECalendarStatus status, ECalSourceType type, ETasks *tasks)
{
    e_calendar_table_set_status_message (E_CALENDAR_TABLE (e_tasks_get_calendar_table (tasks)), 
            NULL, -1);
            
}

static void
config_preview_state_changed_cb (GConfClient *client, guint id, GConfEntry *entry, gpointer data)
{
    gboolean state;
    GConfValue *value;
    ETasks *tasks = (ETasks *)data;

    g_return_if_fail (gconf_entry_get_key (entry) != NULL);
    g_return_if_fail ((value = gconf_entry_get_value (entry)) != NULL);

    state = gconf_value_get_bool (value);
    e_tasks_show_preview (tasks, state);
    bonobo_ui_component_set_prop (E_SEARCH_BAR (tasks->priv->search_bar)->ui_component, "/commands/ViewPreview", "state", state ? "1" : "0", NULL);
}

static void
setup_config (ETasks *tasks)
{
    ETasksPrivate *priv;
    guint not;

    priv = tasks->priv;
    
    /* Timezone */
    set_timezone (tasks);
    
    not = calendar_config_add_notification_timezone (timezone_changed_cb, tasks);
    priv->notifications = g_list_prepend (priv->notifications, GUINT_TO_POINTER (not));
    
    not = calendar_config_add_notification_hide_completed_tasks (config_hide_completed_tasks_changed_cb, 
                                  tasks);
    priv->notifications = g_list_prepend (priv->notifications, GUINT_TO_POINTER (not));
    
    not = calendar_config_add_notification_hide_completed_tasks_units (config_hide_completed_tasks_changed_cb, 
                                  tasks);
    priv->notifications = g_list_prepend (priv->notifications, GUINT_TO_POINTER (not));
    
    not = calendar_config_add_notification_hide_completed_tasks_value (config_hide_completed_tasks_changed_cb, 
                                  tasks);
    priv->notifications = g_list_prepend (priv->notifications, GUINT_TO_POINTER (not)); 

    not = calendar_config_add_notification_preview_state (config_preview_state_changed_cb, tasks);
    priv->notifications = g_list_prepend (priv->notifications, GUINT_TO_POINTER (not));
}

static void
table_drag_data_get (ETable             *table,
             int                 row,
             int                 col,
             GdkDragContext     *context,
             GtkSelectionData   *selection_data,
             guint               info,
             guint               time,
             ETasks             *tasks)
{
    ETasksPrivate *priv;
    ECalModelComponent *comp_data;

    priv = tasks->priv;

    if (priv->current_uid) {
        ECalModel *model;

        model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
        comp_data = e_cal_model_get_component_at (model, row);

        if (info == TARGET_VCALENDAR) {
            /* we will pass an icalcalendar component for both types */
            char *comp_str;
            icalcomponent *vcal;
        
            vcal = e_cal_util_new_top_level ();
            e_cal_util_add_timezones_from_component (vcal, comp_data->icalcomp);
            icalcomponent_add_component (
                    vcal,
                icalcomponent_new_clone (comp_data->icalcomp));

            comp_str = icalcomponent_as_ical_string (vcal);
            if (comp_str) {
                gtk_selection_data_set (selection_data, selection_data->target,
                            8, comp_str, strlen (comp_str));
            }
            icalcomponent_free (vcal);
        }
    }
}

/*
static void
table_drag_begin (ETable         *table,
          int             row,
          int             col,
          GdkDragContext *context,
          ETasks         *tasks)
{

}


static void
table_drag_end (ETable         *table,
        int             row,
        int             col,
        GdkDragContext *context,
        ETasks         *tasks)
{

}
*/

static void 
table_drag_data_delete (ETable         *table,
            int             row,
            int             col,
            GdkDragContext *context,
            ETasks         *tasks)
{
    ETasksPrivate *priv;
    ECalModelComponent *comp_data;
    ECalModel *model;
    gboolean read_only = TRUE;
    priv = tasks->priv;
    
    model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
    comp_data = e_cal_model_get_component_at (model, row);

    e_cal_is_read_only (comp_data->client, &read_only, NULL);
    if (read_only)
        return;

    if(gdk_drag_drop_succeeded(context))
        e_cal_remove_object (comp_data->client, icalcomponent_get_uid (comp_data->icalcomp), NULL);
}

#define E_TASKS_TABLE_DEFAULT_STATE                 \
    "<?xml version=\"1.0\"?>"                   \
    "<ETableState>"                         \
    "<column source=\"13\"/>"                   \
    "<column source=\"14\"/>"                   \
    "<column source=\"9\"/>"                    \
    "<column source=\"5\"/>"                    \
    "<grouping/>"                           \
    "</ETableState>"

static void
pane_realized (GtkWidget *widget, ETasks *tasks)
{
    gtk_paned_set_position ((GtkPaned *)widget, calendar_config_get_task_vpane_pos ());
}

static void
setup_widgets (ETasks *tasks)
{
    ETasksPrivate *priv;
    ETable *etable;
    ECalModel *model;
    gboolean state;

    priv = tasks->priv;

    priv->search_bar = cal_search_bar_new (CAL_SEARCH_TASKS_DEFAULT);
    g_signal_connect (priv->search_bar, "sexp_changed",
              G_CALLBACK (search_bar_sexp_changed_cb), tasks);
    g_signal_connect (priv->search_bar, "category_changed",
              G_CALLBACK (search_bar_category_changed_cb), tasks);
    config_categories_changed_cb (priv->config_listener, "/apps/evolution/general/category_master_list", tasks);

    gtk_table_attach (GTK_TABLE (tasks), priv->search_bar, 0, 1, 0, 1,
              GTK_EXPAND | GTK_FILL | GTK_SHRINK, 0, 0, 0);
    gtk_widget_show (priv->search_bar);

    /* add the paned widget for the task list and task detail areas */
    priv->paned = gtk_vpaned_new ();
    g_signal_connect (priv->paned, "realize", G_CALLBACK (pane_realized), tasks);

    g_signal_connect (G_OBJECT (priv->paned), "button_release_event",
              G_CALLBACK (vpaned_resized_cb), tasks);
    gtk_table_attach (GTK_TABLE (tasks), priv->paned, 0, 1, 1, 2,
              GTK_EXPAND | GTK_FILL, GTK_EXPAND | GTK_FILL, 0, 0);
    gtk_widget_show (priv->paned);

    /* create the task list */
    priv->tasks_view = e_calendar_table_new ();
    g_object_set_data (priv->tasks_view, "tasks", tasks);
    priv->tasks_view_config = e_calendar_table_config_new (E_CALENDAR_TABLE (priv->tasks_view));
    
    g_signal_connect (priv->tasks_view, "user_created", G_CALLBACK (user_created_cb), tasks);

    etable = e_table_scrolled_get_table (
        E_TABLE_SCROLLED (E_CALENDAR_TABLE (priv->tasks_view)->etable));
    e_table_set_state (etable, E_TASKS_TABLE_DEFAULT_STATE);
    gtk_paned_add1 (GTK_PANED (priv->paned), priv->tasks_view);
    gtk_widget_show (priv->tasks_view);


    e_table_drag_source_set (etable, GDK_BUTTON1_MASK,
                 list_drag_types, num_list_drag_types,
                 GDK_ACTION_MOVE|GDK_ACTION_COPY|GDK_ACTION_ASK);
    
    g_signal_connect (etable, "table_drag_data_get",
              G_CALLBACK(table_drag_data_get), tasks);
    g_signal_connect (etable, "table_drag_data_delete",
              G_CALLBACK(table_drag_data_delete), tasks);

    /*
    e_table_drag_dest_set (e_table_scrolled_get_table (E_TABLE_SCROLLED (editor->table)),
                   0, list_drag_types, num_list_drag_types, GDK_ACTION_LINK);

    g_signal_connect (e_table_scrolled_get_table (E_TABLE_SCROLLED (editor->table)),
              "table_drag_motion", G_CALLBACK(table_drag_motion_cb), editor);
    g_signal_connect (e_table_scrolled_get_table (E_TABLE_SCROLLED (editor->table)),
              "table_drag_drop", G_CALLBACK (table_drag_drop_cb), editor);
    g_signal_connect (e_table_scrolled_get_table (E_TABLE_SCROLLED (editor->table)),
              "table_drag_data_received", G_CALLBACK(table_drag_data_received_cb), editor);
    */

    g_signal_connect (etable, "cursor_change", G_CALLBACK (table_cursor_change_cb), tasks);
    g_signal_connect (etable, "selection_change", G_CALLBACK (table_selection_change_cb), tasks);

    /* Timeout check to hide completed items */
    priv->update_timeout = g_timeout_add_full (G_PRIORITY_LOW, 60000, (GSourceFunc) update_view_cb, tasks, NULL);   

    /* create the task detail */
    priv->preview = e_cal_component_preview_new ();
    e_cal_component_preview_set_default_timezone (E_CAL_COMPONENT_PREVIEW (priv->preview), calendar_config_get_icaltimezone ());    
    gtk_paned_add2 (GTK_PANED (priv->paned), priv->preview);
    state = calendar_config_get_preview_state ();

    if (state)
        gtk_widget_show (priv->preview);

    model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
    g_signal_connect (G_OBJECT (model), "model_row_changed",
              G_CALLBACK (model_row_changed_cb), tasks);
    
    g_signal_connect (G_OBJECT (model), "cal_view_progress",
                G_CALLBACK (view_progress_cb), tasks);
    g_signal_connect (G_OBJECT (model), "cal_view_done",
                G_CALLBACK (view_done_cb), tasks);
}

/* Class initialization function for the gnome calendar */
static void
e_tasks_class_init (ETasksClass *class)
{
    GtkObjectClass *object_class;

    object_class = (GtkObjectClass *) class;

    e_tasks_signals[SELECTION_CHANGED] =
        gtk_signal_new ("selection_changed",
                GTK_RUN_LAST,
                G_TYPE_FROM_CLASS (object_class), 
                GTK_SIGNAL_OFFSET (ETasksClass, selection_changed),
                gtk_marshal_NONE__INT,
                GTK_TYPE_NONE, 1,
                GTK_TYPE_INT);

    e_tasks_signals[SOURCE_ADDED] =
        g_signal_new ("source_added",
                  G_TYPE_FROM_CLASS (object_class),
                  G_SIGNAL_RUN_FIRST,
                  G_STRUCT_OFFSET (ETasksClass, source_added),
                  NULL, NULL,
                  e_calendar_marshal_VOID__OBJECT,
                  G_TYPE_NONE,
                  1,
                  G_TYPE_OBJECT);

    e_tasks_signals[SOURCE_REMOVED] =
        g_signal_new ("source_removed",
                  G_TYPE_FROM_CLASS (object_class),
                  G_SIGNAL_RUN_FIRST,
                  G_STRUCT_OFFSET (ETasksClass, source_removed),
                  NULL, NULL,
                  e_calendar_marshal_VOID__OBJECT,
                  G_TYPE_NONE,
                  1,
                  G_TYPE_OBJECT);

    object_class->destroy = e_tasks_destroy;

    class->selection_changed = NULL;
    class->source_added = NULL;
    class->source_removed = NULL;
}


static void
config_categories_changed_cb (EConfigListener *config_listener, const char *key, gpointer user_data)
{
    GList *cat_list;
    GPtrArray *cat_array;
    ETasksPrivate *priv;
    ETasks *tasks = user_data;

    priv = tasks->priv;

    cat_array = g_ptr_array_new ();
    cat_list = e_categories_get_list ();
    while (cat_list != NULL) {
        if (e_categories_is_searchable ((const char *) cat_list->data))
            g_ptr_array_add (cat_array, cat_list->data);
        cat_list = g_list_remove (cat_list, cat_list->data);
    }

    cal_search_bar_set_categories ((CalSearchBar *)priv->search_bar, cat_array);

    g_ptr_array_free (cat_array, TRUE);
}

/* Object initialization function for the gnome calendar */
static void
e_tasks_init (ETasks *tasks)
{
    ETasksPrivate *priv;
    
    priv = g_new0 (ETasksPrivate, 1);
    tasks->priv = priv;

    priv->config_listener = e_config_listener_new ();
    g_signal_connect (priv->config_listener, "key_changed", G_CALLBACK (config_categories_changed_cb), tasks);

    setup_config (tasks);
    setup_widgets (tasks);

    priv->clients = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_object_unref);    
    priv->query = NULL;
    priv->view_instance = NULL;
    priv->view_menus = NULL;
    priv->current_uid = NULL;
    priv->sexp = g_strdup ("#t");
    priv->default_client = NULL;
    priv->tasks_menu = e_cal_menu_new ("org.gnome.evolution.tasks.view");
    update_view (tasks);
}

GtkWidget *
e_tasks_new (void)
{
    ETasks *tasks;

    tasks = g_object_new (e_tasks_get_type (), NULL);

    return GTK_WIDGET (tasks);
}


void
e_tasks_set_ui_component (ETasks *tasks,
              BonoboUIComponent *ui_component)
{
    g_return_if_fail (E_IS_TASKS (tasks));
    g_return_if_fail (ui_component == NULL || BONOBO_IS_UI_COMPONENT (ui_component));

    e_search_bar_set_ui_component (E_SEARCH_BAR (tasks->priv->search_bar), ui_component);
}


static void
e_tasks_destroy (GtkObject *object)
{
    ETasks *tasks;
    ETasksPrivate *priv;

    g_return_if_fail (object != NULL);
    g_return_if_fail (E_IS_TASKS (object));

    tasks = E_TASKS (object);
    priv = tasks->priv;

    if (priv) {
        GList *l;

        /* unset the config listener */
        if (priv->config_listener) {
            g_signal_handlers_disconnect_matched (priv->config_listener,
                                  G_SIGNAL_MATCH_DATA,
                                  0, 0, NULL, NULL, tasks);
            g_object_unref (priv->config_listener);
            priv->config_listener = NULL;
        }

        /* disconnect from signals on all the clients */
        for (l = priv->clients_list; l != NULL; l = l->next) {
            g_signal_handlers_disconnect_matched (l->data, G_SIGNAL_MATCH_DATA,
                                  0, 0, NULL, NULL, tasks);
        }

        g_hash_table_destroy (priv->clients);
        g_list_free (priv->clients_list);

        if (priv->default_client)
            g_object_unref (priv->default_client);
        priv->default_client = NULL;

        if (priv->current_uid) {
            g_free (priv->current_uid);
            priv->current_uid = NULL;
        }
    
        if (priv->sexp) {
            g_free (priv->sexp);
            priv->sexp = NULL;
        }

        if (priv->update_timeout) {
            g_source_remove (priv->update_timeout);
            priv->update_timeout = 0;
        }
    
        if (priv->tasks_view_config) {
            g_object_unref (priv->tasks_view_config);
            priv->tasks_view_config = NULL;
        }
        
        for (l = priv->notifications; l; l = l->next)
            calendar_config_remove_notification (GPOINTER_TO_UINT (l->data));
        priv->notifications = NULL;

        g_free (priv);
        tasks->priv = NULL;
    }

    if (GTK_OBJECT_CLASS (e_tasks_parent_class)->destroy)
        (* GTK_OBJECT_CLASS (e_tasks_parent_class)->destroy) (object);
}

static void
set_status_message (ETasks *tasks, const char *message, ...)
{
    ETasksPrivate *priv;
    va_list args;
    char sz[2048], *msg_string = NULL;

    if (message) {
        va_start (args, message);
        vsnprintf (sz, sizeof sz, message, args);
        va_end (args);
        msg_string = sz;
    }

    priv = tasks->priv;
    
    e_calendar_table_set_status_message (E_CALENDAR_TABLE (priv->tasks_view), msg_string, -1);
}

/* Callback from the calendar client when an error occurs in the backend */
static void
backend_error_cb (ECal *client, const char *message, gpointer data)
{
    ETasks *tasks;
    char *errmsg;
    char *urinopwd;

    tasks = E_TASKS (data);

    urinopwd = get_uri_without_password (e_cal_get_uri (client));
    errmsg = g_strdup_printf (_("Error on %s:\n %s"), urinopwd, message);
    gnome_error_dialog_parented (errmsg, GTK_WINDOW (gtk_widget_get_toplevel (GTK_WIDGET (tasks))));
    g_free (errmsg);
    g_free (urinopwd);
}

/* Callback from the calendar client when the backend dies */
static void
backend_died_cb (ECal *client, gpointer data)
{
    ETasks *tasks;
    ETasksPrivate *priv;
    ESource *source;
    
    tasks = E_TASKS (data);
    priv = tasks->priv;

    source = g_object_ref (e_cal_get_source (client));

    priv->clients_list = g_list_remove (priv->clients_list, client);
    g_hash_table_remove (priv->clients,  e_source_peek_uid (source));

    gtk_signal_emit (GTK_OBJECT (tasks), e_tasks_signals[SOURCE_REMOVED], source);

    e_calendar_table_set_status_message (E_CALENDAR_TABLE (e_tasks_get_calendar_table (tasks)), NULL, -1);
    
    e_error_run (GTK_WINDOW (gtk_widget_get_toplevel (GTK_WIDGET (tasks))),
             "calendar:tasks-crashed", NULL);
    
    g_object_unref (source);
}

/* Callback from the calendar client when the calendar is opened */
static void
client_cal_opened_cb (ECal *ecal, ECalendarStatus status, ETasks *tasks)
{
    ECalModel *model;
    ESource *source;
    ETasksPrivate *priv;

    priv = tasks->priv;

    source = e_cal_get_source (ecal);

    switch (status) {
    case E_CALENDAR_STATUS_OK :
        g_signal_handlers_disconnect_matched (ecal, G_SIGNAL_MATCH_FUNC, 0, 0, NULL, client_cal_opened_cb, NULL);

        set_status_message (tasks, _("Loading tasks"));
        model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
        e_cal_model_add_client (model, ecal);

        set_status_message (tasks, NULL);
        break;
    case E_CALENDAR_STATUS_BUSY :
        break;
    case E_CALENDAR_STATUS_REPOSITORY_OFFLINE:
        e_error_run (GTK_WINDOW (gtk_widget_get_toplevel (GTK_WIDGET (tasks))), "calendar:prompt-no-contents-offline-tasks", NULL);
    default :
        /* Make sure the source doesn't disappear on us */
        g_object_ref (source);

        priv->clients_list = g_list_remove (priv->clients_list, ecal);
        g_signal_handlers_disconnect_matched (ecal, G_SIGNAL_MATCH_DATA,
                              0, 0, NULL, NULL, tasks);

        /* Do this last because it unrefs the client */
        g_hash_table_remove (priv->clients,  e_source_peek_uid (source));

        gtk_signal_emit (GTK_OBJECT (tasks), e_tasks_signals[SOURCE_REMOVED], source);

        set_status_message (tasks, NULL);
        g_object_unref (source);

        break;
    }
}

static void
default_client_cal_opened_cb (ECal *ecal, ECalendarStatus status, ETasks *tasks)
{
    ECalModel *model;
    ESource *source;
    ETasksPrivate *priv;

    priv = tasks->priv;

    source = e_cal_get_source (ecal);

    switch (status) {
    case E_CALENDAR_STATUS_OK :
        g_signal_handlers_disconnect_matched (ecal, G_SIGNAL_MATCH_FUNC, 0, 0, NULL, default_client_cal_opened_cb, NULL);
        model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
        
        e_cal_model_set_default_client (model, ecal);
        set_status_message (tasks, NULL);
        break;
    case E_CALENDAR_STATUS_BUSY:
        break;
    default :
        /* Make sure the source doesn't disappear on us */
        g_object_ref (source);

        priv->clients_list = g_list_remove (priv->clients_list, ecal);
        g_signal_handlers_disconnect_matched (ecal, G_SIGNAL_MATCH_DATA,
                              0, 0, NULL, NULL, tasks);

        /* Do this last because it unrefs the client */
        g_hash_table_remove (priv->clients,  e_source_peek_uid (source));

        gtk_signal_emit (GTK_OBJECT (tasks), e_tasks_signals[SOURCE_REMOVED], source);

        set_status_message (tasks, NULL);
        g_object_unref (priv->default_client);
        priv->default_client = NULL;
        g_object_unref (source);

        break;
    }
}

typedef void (*open_func) (ECal *, ECalendarStatus, ETasks *);

static gboolean
open_ecal (ETasks *tasks, ECal *cal, gboolean only_if_exists, open_func of)
{
    ETasksPrivate *priv;
    icaltimezone *zone;

    priv = tasks->priv;
    
    zone = calendar_config_get_icaltimezone ();
    e_cal_set_default_timezone (cal, zone, NULL);

    
    set_status_message (tasks, _("Opening tasks at %s"), e_cal_get_uri (cal));

    g_signal_connect (G_OBJECT (cal), "cal_opened", G_CALLBACK (of), tasks);
    e_cal_open_async (cal, only_if_exists);

    return TRUE;
}

void
e_tasks_open_task           (ETasks     *tasks)
{
    ECalendarTable *cal_table;
                                                                                
    cal_table = e_tasks_get_calendar_table (tasks);
    e_calendar_table_open_selected (cal_table);
}

void
e_tasks_new_task            (ETasks     *tasks)
{
    ETasksPrivate *priv;
    TaskEditor *tedit;
    ECalComponent *comp;
    const char *category;
    ECal *ecal;
    guint32 flags = 0;
    
    g_return_if_fail (E_IS_TASKS (tasks));

    priv = tasks->priv;

    /* FIXME What to do about no default client */
    ecal = e_tasks_get_default_client (tasks);
    if (!ecal)
        return;
    
    flags |= COMP_EDITOR_NEW_ITEM | COMP_EDITOR_USER_ORG;
    
    comp = cal_comp_task_new_with_defaults (ecal);

    category = cal_search_bar_get_category (CAL_SEARCH_BAR (priv->search_bar));
    e_cal_component_set_categories (comp, category);

    tedit = task_editor_new (ecal, flags);
    comp_editor_edit_comp (COMP_EDITOR (tedit), comp);
    g_object_unref (comp);

    comp_editor_focus (COMP_EDITOR (tedit));
}

void
e_tasks_show_preview (ETasks *tasks, gboolean state)
{
    ETasksPrivate *priv;

    g_return_if_fail (tasks != NULL);
    g_return_if_fail (E_IS_TASKS (tasks));
    priv = tasks->priv;

    if (state) {
        ECalModel *model;
        ECalModelComponent *comp_data;
        ECalComponent *comp;
        ETable *etable;
        const char *uid;
        int n_selected;
        
        etable = e_table_scrolled_get_table (E_TABLE_SCROLLED (E_CALENDAR_TABLE (priv->tasks_view)->etable));
        n_selected = e_table_selected_count (etable);
        
        if (n_selected != 1) {
            e_cal_component_preview_clear (E_CAL_COMPONENT_PREVIEW (priv->preview));
        } else {
            model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
            
            comp_data = e_cal_model_get_component_at (model, e_table_get_cursor_row (etable));
            comp = e_cal_component_new ();
            e_cal_component_set_icalcomponent (comp, icalcomponent_new_clone (comp_data->icalcomp));
        
            e_cal_component_preview_display (E_CAL_COMPONENT_PREVIEW (priv->preview), comp_data->client, comp);
            
            e_cal_component_get_uid (comp, &uid);
            if (priv->current_uid)
                g_free (priv->current_uid);
            priv->current_uid = g_strdup (uid);
            
            g_object_unref (comp);
        }
        gtk_widget_show (priv->preview);

    } else  {
        e_cal_component_preview_clear (E_CAL_COMPONENT_PREVIEW (priv->preview));        
        gtk_widget_hide (priv->preview);
    }
}

gboolean
e_tasks_add_todo_source (ETasks *tasks, ESource *source)
{
    ETasksPrivate *priv;
    ECal *client;
    const char *uid;

    g_return_val_if_fail (tasks != NULL, FALSE);
    g_return_val_if_fail (E_IS_TASKS (tasks), FALSE);
    g_return_val_if_fail (E_IS_SOURCE (source), FALSE);

    priv = tasks->priv;

    uid = e_source_peek_uid (source);
    client = g_hash_table_lookup (priv->clients, uid);
    if (client) {
        /* We already have it */

        return TRUE;
    } else {
        ESource *default_source;
        
        if (priv->default_client) {
            default_source = e_cal_get_source (priv->default_client);
        
            /* We don't have it but the default client is it */
            if (!strcmp (e_source_peek_uid (default_source), uid))
                client = g_object_ref (priv->default_client);
        }

        /* Create a new one */
        if (!client) {
            client = auth_new_cal_from_source (source, E_CAL_SOURCE_TYPE_TODO);
            if (!client)
                return FALSE;
        }
    }

    g_signal_connect (G_OBJECT (client), "backend_error", G_CALLBACK (backend_error_cb), tasks);
    g_signal_connect (G_OBJECT (client), "backend_died", G_CALLBACK (backend_died_cb), tasks);

    /* add the client to internal structure */  
    g_hash_table_insert (priv->clients, g_strdup (uid) , client);
    priv->clients_list = g_list_prepend (priv->clients_list, client);

    gtk_signal_emit (GTK_OBJECT (tasks), e_tasks_signals[SOURCE_ADDED], source);

    open_ecal (tasks, client, FALSE, client_cal_opened_cb);

    return TRUE;
}

gboolean
e_tasks_remove_todo_source (ETasks *tasks, ESource *source)
{
    ETasksPrivate *priv;
    ECal *client;
    ECalModel *model;
    const char *uid;

    g_return_val_if_fail (tasks != NULL, FALSE);
    g_return_val_if_fail (E_IS_TASKS (tasks), FALSE);
    g_return_val_if_fail (E_IS_SOURCE (source), FALSE);

    priv = tasks->priv;

    uid = e_source_peek_uid (source);
    client = g_hash_table_lookup (priv->clients, uid);
    if (!client) 
        return TRUE;
    

    priv->clients_list = g_list_remove (priv->clients_list, client);
    g_signal_handlers_disconnect_matched (client, G_SIGNAL_MATCH_DATA,
                          0, 0, NULL, NULL, tasks); 

    model = e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view));
    e_cal_model_remove_client (model, client);

    g_hash_table_remove (priv->clients, uid);
       

    gtk_signal_emit (GTK_OBJECT (tasks), e_tasks_signals[SOURCE_REMOVED], source);

    return TRUE;
}

gboolean
e_tasks_set_default_source (ETasks *tasks, ESource *source)
{
    ETasksPrivate *priv;
    ECal *ecal;
    
    g_return_val_if_fail (tasks != NULL, FALSE);
    g_return_val_if_fail (E_IS_TASKS (tasks), FALSE);
    g_return_val_if_fail (E_IS_SOURCE (source), FALSE);

    priv = tasks->priv;

    ecal = g_hash_table_lookup (priv->clients, e_source_peek_uid (source));

    if (priv->default_client)
        g_object_unref (priv->default_client);

    if (ecal) {
        priv->default_client = g_object_ref (ecal);
    } else {
        priv->default_client = auth_new_cal_from_source (source, E_CAL_SOURCE_TYPE_TODO);
        if (!priv->default_client)
            return FALSE;
    }

    open_ecal (tasks, priv->default_client, FALSE, default_client_cal_opened_cb);

    return TRUE;
}

ECal *
e_tasks_get_default_client (ETasks *tasks)
{
    ETasksPrivate *priv;
    
    g_return_val_if_fail (tasks != NULL, NULL);
    g_return_val_if_fail (E_IS_TASKS (tasks), NULL);

    priv = tasks->priv;

    return e_cal_model_get_default_client (e_calendar_table_get_model (E_CALENDAR_TABLE (priv->tasks_view)));   
}

/**
 * e_tasks_complete_selected:
 * @tasks: A tasks control widget
 * 
 * Marks the selected tasks complete
 **/
void
e_tasks_complete_selected (ETasks *tasks)
{
    ETasksPrivate *priv;
    ECalendarTable *cal_table;

    g_return_if_fail (tasks != NULL);
    g_return_if_fail (E_IS_TASKS (tasks));

    priv = tasks->priv;

    cal_table = E_CALENDAR_TABLE (priv->tasks_view);

    set_status_message (tasks, _("Completing tasks..."));
    e_calendar_table_complete_selected (cal_table);
    set_status_message (tasks, NULL);
}

/**
 * e_tasks_delete_selected:
 * @tasks: A tasks control widget.
 * 
 * Deletes the selected tasks in the task list.
 **/
void
e_tasks_delete_selected (ETasks *tasks)
{
    ETasksPrivate *priv;
    ECalendarTable *cal_table;

    g_return_if_fail (tasks != NULL);
    g_return_if_fail (E_IS_TASKS (tasks));

    priv = tasks->priv;

    cal_table = E_CALENDAR_TABLE (priv->tasks_view);
    set_status_message (tasks, _("Deleting selected objects..."));
    e_calendar_table_delete_selected (cal_table);
    set_status_message (tasks, NULL);

    e_cal_component_preview_clear (E_CAL_COMPONENT_PREVIEW (priv->preview));
}

/**
 * e_tasks_expunge:
 * @tasks: A tasks control widget
 * 
 * Removes all tasks marked as completed
 **/
void
e_tasks_delete_completed (ETasks *tasks)
{
    ETasksPrivate *priv;
    char *sexp;
    GList *l;
    
    g_return_if_fail (tasks != NULL);
    g_return_if_fail (E_IS_TASKS (tasks));

    priv = tasks->priv;

    sexp = g_strdup ("(is-completed?)");

    set_status_message (tasks, _("Expunging")); 

    for (l = priv->clients_list; l != NULL; l = l->next) {
        ECal *client = l->data;
        GList *objects, *m;
        gboolean read_only = TRUE;
        
        e_cal_is_read_only (client, &read_only, NULL);
        if (read_only)
            continue;
        
        if (!e_cal_get_object_list (client, sexp, &objects, NULL)) {
            g_warning (G_STRLOC ": Could not get the objects");
            
            continue;
        }
        
        for (m = objects; m; m = m->next) {
            /* FIXME Better error handling */
            e_cal_remove_object (client, icalcomponent_get_uid (m->data), NULL);
        }

        g_list_foreach (objects, (GFunc) icalcomponent_free, NULL);
        g_list_free (objects);
    }

    set_status_message (tasks, NULL);

    g_free (sexp);
}

/* Callback used from the view collection when we need to display a new view */
static void
display_view_cb (GalViewInstance *instance, GalView *view, gpointer data)
{
    ETasks *tasks;

    tasks = E_TASKS (data);

    if (GAL_IS_VIEW_ETABLE (view)) {
        gal_view_etable_attach_table (GAL_VIEW_ETABLE (view), e_table_scrolled_get_table (E_TABLE_SCROLLED (E_CALENDAR_TABLE (tasks->priv->tasks_view)->etable)));
    }

    gtk_paned_set_position ((GtkPaned *)tasks->priv->paned, calendar_config_get_task_vpane_pos ());
}

/**
 * e_tasks_setup_view_menus:
 * @tasks: A tasks widget.
 * @uic: UI controller to use for the menus.
 * 
 * Sets up the #GalView menus for a tasks control.  This function should be
 * called from the Bonobo control activation callback for this tasks control.
 * Also, the menus should be discarded using e_tasks_discard_view_menus().
 **/
void
e_tasks_setup_view_menus (ETasks *tasks, BonoboUIComponent *uic)
{
    ETasksPrivate *priv;
    GalViewFactory *factory;
    ETableSpecification *spec;
    char *dir0, *dir1, *filename;
    static GalViewCollection *collection = NULL;

    g_return_if_fail (tasks != NULL);
    g_return_if_fail (E_IS_TASKS (tasks));
    g_return_if_fail (uic != NULL);
    g_return_if_fail (BONOBO_IS_UI_COMPONENT (uic));

    priv = tasks->priv;

    g_return_if_fail (priv->view_instance == NULL);

    g_assert (priv->view_instance == NULL);
    g_assert (priv->view_menus == NULL);

    /* Create the view instance */

    if (collection == NULL) {
        collection = gal_view_collection_new ();

        gal_view_collection_set_title (collection, _("Tasks"));

        dir0 = g_build_filename (EVOLUTION_GALVIEWSDIR,
                     "tasks",
                     NULL);
        dir1 = g_build_filename (tasks_component_peek_base_directory (tasks_component_peek ()), 
                     "tasks", "views", NULL);
        gal_view_collection_set_storage_directories (collection,
                                 dir0,
                                 dir1);
        g_free (dir1);
        g_free (dir0);

        /* Create the views */

        spec = e_table_specification_new ();
        filename = g_build_filename (EVOLUTION_ETSPECDIR,
                         "e-calendar-table.etspec",
                         NULL);
        e_table_specification_load_from_file (spec, filename);
        g_free (filename);

        factory = gal_view_factory_etable_new (spec);
        g_object_unref (spec);
        gal_view_collection_add_factory (collection, factory);
        g_object_unref (factory);

        /* Load the collection and create the menus */

        gal_view_collection_load (collection);
    }

    priv->view_instance = gal_view_instance_new (collection, NULL);

    priv->view_menus = gal_view_menus_new (priv->view_instance);
    gal_view_menus_apply (priv->view_menus, uic, NULL);
    g_signal_connect (priv->view_instance, "display_view", G_CALLBACK (display_view_cb), tasks);
    display_view_cb (priv->view_instance, gal_view_instance_get_current_view (priv->view_instance), tasks);
}

/**
 * e_tasks_discard_view_menus:
 * @tasks: A tasks widget.
 * 
 * Discards the #GalView menus used by a tasks control.  This function should be
 * called from the Bonobo control deactivation callback for this tasks control.
 * The menus should have been set up with e_tasks_setup_view_menus().
 **/
void
e_tasks_discard_view_menus (ETasks *tasks)
{
    ETasksPrivate *priv;

    g_return_if_fail (tasks != NULL);
    g_return_if_fail (E_IS_TASKS (tasks));

    priv = tasks->priv;

    g_return_if_fail (priv->view_instance != NULL);

    g_assert (priv->view_instance != NULL);
    g_assert (priv->view_menus != NULL);

    g_object_unref (priv->view_instance);
    priv->view_instance = NULL;

    g_object_unref (priv->view_menus);
    priv->view_menus = NULL;
}

/**
 * e_tasks_get_calendar_table:
 * @tasks: A tasks widget.
 * 
 * Queries the #ECalendarTable contained in a tasks widget.
 * 
 * Return value: The #ECalendarTable that the tasks widget uses to display its
 * information.
 **/
ECalendarTable *
e_tasks_get_calendar_table (ETasks *tasks)
{
    ETasksPrivate *priv;

    g_return_val_if_fail (tasks != NULL, NULL);
    g_return_val_if_fail (E_IS_TASKS (tasks), NULL);

    priv = tasks->priv;
    return E_CALENDAR_TABLE (priv->tasks_view);
}