path: root/calendar/gui/e-timezone-entry.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */

/*
 * Author :
 *  Damon Chaplin <damon@ximian.com>
 *
 * Copyright 2001, Ximian, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * 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
 */

/*
 * ETimezoneEntry - a field for setting a timezone. It shows the timezone in
 * a GtkEntry with a '...' button beside it which shows a dialog for changing
 * the timezone. The dialog contains a map of the world with a point for each
 * timezone, and an option menu as an alternative way of selecting the
 * timezone.
 */

#include <config.h>
#include <gtk/gtkbutton.h>
#include <gtk/gtkentry.h>
#include <gtk/gtksignal.h>
#include <gnome.h>
#include "dialogs/e-timezone-dialog.h"
#include "e-timezone-entry.h"


struct _ETimezoneEntryPrivate {
    /* This is the timezone set in e_timezone_entry_set_timezone().
       Note that we don't copy it or use a ref count - we assume it is
       never destroyed for the lifetime of this widget. */
    icaltimezone *zone;
    
    /* This is TRUE if the timezone has been changed since being set.
       If it hasn't, we can just return zone, If it has, we return the
       builtin timezone with tzid. (It can only be changed to a builtin
       timezone, or to 'local time', i.e. no timezone.) */
    gboolean changed;

    GtkWidget *entry;
    GtkWidget *button;
};


enum {
  CHANGED,
  LAST_SIGNAL
};


static void e_timezone_entry_class_init (ETimezoneEntryClass    *class);
static void e_timezone_entry_init   (ETimezoneEntry *tentry);
static void e_timezone_entry_destroy    (GtkObject  *object);

static void on_entry_changed        (GtkEntry   *entry,
                     ETimezoneEntry *tentry);
static void on_button_clicked       (GtkWidget  *widget,
                     ETimezoneEntry *tentry);

static char* e_timezone_entry_get_display_name  (icaltimezone   *zone);


static GtkHBoxClass *parent_class;
static guint timezone_entry_signals[LAST_SIGNAL] = { 0 };


/**
 * e_timezone_entry_get_type:
 *
 * Returns the GtkType for the ETimezoneEntry widget
 */
guint
e_timezone_entry_get_type       (void)
{
    static guint timezone_entry_type = 0;

    if (!timezone_entry_type){
        GtkTypeInfo timezone_entry_info = {
            "ETimezoneEntry",
            sizeof (ETimezoneEntry),
            sizeof (ETimezoneEntryClass),
            (GtkClassInitFunc) e_timezone_entry_class_init,
            (GtkObjectInitFunc) e_timezone_entry_init,
            NULL,
            NULL,
        };

        timezone_entry_type = gtk_type_unique (gtk_hbox_get_type (), &timezone_entry_info);
    }
    
    return timezone_entry_type;
}


static void
e_timezone_entry_class_init     (ETimezoneEntryClass    *class)
{
    GtkObjectClass *object_class = (GtkObjectClass *) class;

    object_class = (GtkObjectClass*) class;

    parent_class = gtk_type_class (gtk_hbox_get_type ());

    timezone_entry_signals[CHANGED] =
        gtk_signal_new ("changed",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ETimezoneEntryClass,
                           changed),
                gtk_marshal_NONE__NONE,
                GTK_TYPE_NONE, 0);

    gtk_object_class_add_signals (object_class, timezone_entry_signals,
                      LAST_SIGNAL);

    object_class->destroy       = e_timezone_entry_destroy;

    class->changed = NULL;
}


static void
e_timezone_entry_init       (ETimezoneEntry *tentry)
{
    ETimezoneEntryPrivate *priv;

    tentry->priv = priv = g_new0 (ETimezoneEntryPrivate, 1);

    priv->zone = NULL;
    priv->changed = FALSE;

    priv->entry  = gtk_entry_new ();
    gtk_entry_set_editable (GTK_ENTRY (priv->entry), FALSE);
    /*gtk_widget_set_usize (priv->date_entry, 90, 0);*/
    gtk_box_pack_start (GTK_BOX (tentry), priv->entry, TRUE, TRUE, 0);
    gtk_widget_show (priv->entry);
    gtk_signal_connect (GTK_OBJECT (priv->entry), "changed",
                GTK_SIGNAL_FUNC (on_entry_changed), tentry);
    
    priv->button = gtk_button_new_with_label ("...");
    gtk_signal_connect (GTK_OBJECT (priv->button), "clicked",
                GTK_SIGNAL_FUNC (on_button_clicked), tentry);
    gtk_box_pack_start (GTK_BOX (tentry), priv->button, FALSE, FALSE, 0);
    gtk_widget_show (priv->button);
}


/**
 * e_timezone_entry_new:
 *
 * Description: Creates a new #ETimezoneEntry widget which can be used
 * to provide an easy to use way for entering dates and times.
 * 
 * Returns: a new #ETimezoneEntry widget.
 */
GtkWidget *
e_timezone_entry_new            (void)
{
    ETimezoneEntry *tentry;

    tentry = gtk_type_new (e_timezone_entry_get_type ());

    return GTK_WIDGET (tentry);
}


static void
e_timezone_entry_destroy        (GtkObject  *object)
{
    ETimezoneEntry *tentry;
    ETimezoneEntryPrivate *priv;

    g_return_if_fail (E_IS_TIMEZONE_ENTRY (object));

    tentry = E_TIMEZONE_ENTRY (object);
    priv = tentry->priv;

    g_free (tentry->priv);
    tentry->priv = NULL;

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


/* The arrow button beside the date field has been clicked, so we show the
   popup with the ECalendar in. */
static void
on_button_clicked       (GtkWidget  *widget,
                 ETimezoneEntry *tentry)
{
    ETimezoneEntryPrivate *priv;
    ETimezoneDialog *timezone_dialog;
    GtkWidget *dialog;
    char *tzid = NULL, *display_name, *old_display_name;

    priv = tentry->priv;

    display_name = gtk_entry_get_text (GTK_ENTRY (priv->entry));

    if (priv->zone)
        tzid = icaltimezone_get_tzid (priv->zone);

    timezone_dialog = e_timezone_dialog_new ();
    e_timezone_dialog_set_timezone (timezone_dialog, tzid, display_name);

    dialog = e_timezone_dialog_get_toplevel (timezone_dialog);

    if (gnome_dialog_run_and_close (GNOME_DIALOG (dialog)) == 0) {
        tzid = e_timezone_dialog_get_timezone (E_TIMEZONE_DIALOG (timezone_dialog), &display_name);
        old_display_name = gtk_entry_get_text (GTK_ENTRY (priv->entry));
        /* See if the timezone has been changed. It can only have been
           changed to a builtin timezone, in which case the returned
           TZID will be NULL. */
        if (strcmp (old_display_name, display_name)
            || (!tzid && priv->zone)) {
            priv->changed = TRUE;
            priv->zone = NULL;
        }

        gtk_entry_set_text (GTK_ENTRY (priv->entry), display_name);
    }

    gtk_object_unref (GTK_OBJECT (timezone_dialog));
}


static void
on_entry_changed            (GtkEntry   *entry,
                     ETimezoneEntry *tentry)
{
    gtk_signal_emit (GTK_OBJECT (tentry), timezone_entry_signals[CHANGED]);
}


icaltimezone*
e_timezone_entry_get_timezone       (ETimezoneEntry *tentry)
{
    ETimezoneEntryPrivate *priv;
    char *display_name;

    g_return_val_if_fail (E_IS_TIMEZONE_ENTRY (tentry), NULL);

    priv = tentry->priv;

    /* If the timezone hasn't been change, we can just return the same
       zone we were passed in. */
    if (!priv->changed)
        return priv->zone;

    /* If the timezone has changed, it can only have been changed to a
       builtin timezone or 'local time' (i.e. no timezone). */
    display_name = gtk_entry_get_text (GTK_ENTRY (priv->entry));

    if (display_name && display_name[0])
        return icaltimezone_get_builtin_timezone (display_name);
    return NULL;
}


void
e_timezone_entry_set_timezone       (ETimezoneEntry *tentry,
                     icaltimezone   *zone)
{
    ETimezoneEntryPrivate *priv;

    g_return_if_fail (E_IS_TIMEZONE_ENTRY (tentry));

    priv = tentry->priv;

    priv->zone = zone;
    priv->changed = FALSE;

    gtk_entry_set_text (GTK_ENTRY (priv->entry),
                zone ? e_timezone_entry_get_display_name (zone) : "");
}


/* Returns the timezone name to display to the user. . We prefer to use the
   Olson city name, but fall back on the TZNAME, or finally the TZID. We don't
   want to use "" as it may be wrongly interpreted as a 'local time'. */
static char*
e_timezone_entry_get_display_name   (icaltimezone   *zone)
{
    char *display_name;

    display_name = icaltimezone_get_location (zone);
    if (!display_name)
        display_name = icaltimezone_get_tznames (zone);
    if (!display_name)
        display_name = icaltimezone_get_tzid (zone);

    return display_name;
}