path: root/widgets/misc/e-calendar.c

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

/*
 * Author :
 *  Damon Chaplin <damon@helixcode.com>
 *
 * Copyright 2000, Helix Code, 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
 */

/*
 * ECalendar - displays a table of monthly calendars, allowing highlighting
 * and selection of one or more days. Like GtkCalendar with more features.
 * Most of the functionality is in the ECalendarItem canvas item, though
 * we also add GnomeCanvasWidget buttons to go to the previous/next month and
 * to got to the current day.
 */

#include <config.h>
#include <e-util/e-util.h>
#include "e-calendar.h"

#define E_CALENDAR_SMALL_FONT   \
    "-adobe-utopia-regular-r-normal-*-*-100-*-*-p-*-iso8859-*"
#define E_CALENDAR_SMALL_FONT_FALLBACK  \
    "-adobe-helvetica-medium-r-normal-*-*-80-*-*-p-*-iso8859-*"

/* The space between the arrow buttons and the edge of the widget. */
#define E_CALENDAR_ARROW_BUTTON_X_PAD   2
#define E_CALENDAR_ARROW_BUTTON_Y_PAD   0

/* Vertical padding. The padding above the button includes the space for the
   horizontal line. */
#define E_CALENDAR_YPAD_ABOVE_LOWER_BUTTONS     4
#define E_CALENDAR_YPAD_BELOW_LOWER_BUTTONS     3

/* Horizontal padding inside & between buttons. */
#define E_CALENDAR_IXPAD_BUTTONS            4
#define E_CALENDAR_XPAD_BUTTONS             8

/* The time between steps when the prev/next buttons is pressed, in 1/1000ths
   of a second, and the number of timeouts we skip before we start
   automatically moving back/forward. */
#define E_CALENDAR_AUTO_MOVE_TIMEOUT        150
#define E_CALENDAR_AUTO_MOVE_TIMEOUT_DELAY  2

static void e_calendar_class_init   (ECalendarClass *class);
static void e_calendar_init     (ECalendar  *cal);
static void e_calendar_destroy      (GtkObject  *object);
static void e_calendar_realize      (GtkWidget  *widget);
static void e_calendar_style_set    (GtkWidget  *widget,
                     GtkStyle   *previous_style);
static void e_calendar_size_request (GtkWidget      *widget,
                     GtkRequisition *requisition);
static void e_calendar_size_allocate    (GtkWidget  *widget,
                     GtkAllocation  *allocation);
static void e_calendar_draw     (GtkWidget  *widget,
                     GdkRectangle   *area);
static gint e_calendar_focus_in     (GtkWidget  *widget,
                     GdkEventFocus  *event);
static gint e_calendar_focus_out    (GtkWidget  *widget,
                     GdkEventFocus  *event);
static gint e_calendar_key_press    (GtkWidget  *widget,
                     GdkEventKey    *event);
static gint e_calendar_drag_motion  (GtkWidget      *widget,
                     GdkDragContext *context,
                     gint            x,
                     gint            y,
                     guint           time);
static void e_calendar_drag_leave   (GtkWidget      *widget,
                     GdkDragContext *context,
                     guint           time);

static void e_calendar_on_prev_pressed  (ECalendar  *cal);
static void e_calendar_on_prev_released (ECalendar  *cal);
static void e_calendar_on_next_pressed  (ECalendar  *cal);
static void e_calendar_on_next_released (ECalendar  *cal);

static void e_calendar_start_auto_move  (ECalendar  *cal,
                     gboolean    moving_forward);
static gboolean e_calendar_auto_move_handler    (gpointer    data);
static void e_calendar_stop_auto_move   (ECalendar  *cal);

static GnomeCanvasClass *parent_class;
static GtkLayoutClass *grandparent_class;

E_MAKE_TYPE (e_calendar, "ECalendar", ECalendar,
         e_calendar_class_init, e_calendar_init, E_CANVAS_TYPE)


static void
e_calendar_class_init (ECalendarClass *class)
{
    GtkObjectClass *object_class;
    GtkWidgetClass *widget_class;

    object_class = (GtkObjectClass *) class;
    widget_class = (GtkWidgetClass *) class;

    parent_class = gtk_type_class (E_CANVAS_TYPE);
    grandparent_class = gtk_type_class (GTK_TYPE_LAYOUT);

    object_class->destroy = e_calendar_destroy;

    widget_class->realize          = e_calendar_realize;
    widget_class->style_set        = e_calendar_style_set;
    widget_class->size_request     = e_calendar_size_request;
    widget_class->size_allocate    = e_calendar_size_allocate;
    widget_class->draw         = e_calendar_draw;
    widget_class->focus_in_event       = e_calendar_focus_in;
    widget_class->focus_out_event      = e_calendar_focus_out;
    widget_class->key_press_event      = e_calendar_key_press;
    widget_class->drag_motion      = e_calendar_drag_motion;
    widget_class->drag_leave       = e_calendar_drag_leave;
}


static void
e_calendar_init (ECalendar *cal)
{
    GnomeCanvasGroup *canvas_group;
    GdkFont *small_font;
    GtkWidget *button, *arrow;

    /* Create the small font. */
    small_font = gdk_font_load (E_CALENDAR_SMALL_FONT);
    if (!small_font)
        small_font = gdk_font_load (E_CALENDAR_SMALL_FONT_FALLBACK);
    if (!small_font)
        g_warning ("Couldn't load font");

    canvas_group = GNOME_CANVAS_GROUP (GNOME_CANVAS (cal)->root);

    cal->calitem = E_CALENDAR_ITEM (gnome_canvas_item_new (canvas_group,
                                   e_calendar_item_get_type (),
                                   "week_number_font", small_font,
                                   NULL));

    if (small_font)
        gdk_font_unref (small_font);


    /* Create the 'Today' and 'None' buttons but don't show them. */
    cal->today_button = gtk_button_new_with_label (_("Today"));
    cal->today_button_item = gnome_canvas_item_new (canvas_group,
                            gnome_canvas_widget_get_type (),
                            "widget", cal->today_button,
                            NULL);
    gnome_canvas_item_hide (cal->today_button_item);


    cal->none_button = gtk_button_new_with_label (_("None"));
    cal->none_button_item = gnome_canvas_item_new (canvas_group,
                               gnome_canvas_widget_get_type (),
                               "widget", cal->none_button,
                               NULL);
    gnome_canvas_item_hide (cal->none_button_item);


    /* Create the arrow buttons to move to the previous/next month. */
    button = gtk_button_new ();
    /* FIXME: The buttons doesn't display properly if we do this. */
    /*gtk_button_set_relief (GTK_BUTTON (button), GTK_RELIEF_NONE);*/
    gtk_widget_show (button);
    gtk_signal_connect_object (GTK_OBJECT (button), "pressed",
                   GTK_SIGNAL_FUNC (e_calendar_on_prev_pressed),
                   GTK_OBJECT (cal));
    gtk_signal_connect_object (GTK_OBJECT (button), "released",
                   GTK_SIGNAL_FUNC (e_calendar_on_prev_released),
                   GTK_OBJECT (cal));
    arrow = gtk_arrow_new (GTK_ARROW_LEFT, GTK_SHADOW_OUT);
    gtk_widget_show (arrow);
    gtk_container_add (GTK_CONTAINER (button), arrow);
    cal->prev_item = gnome_canvas_item_new (canvas_group,
                        gnome_canvas_widget_get_type (),
                        "widget", button,
                        NULL);

    button = gtk_button_new ();
    /*gtk_button_set_relief (GTK_BUTTON (button), GTK_RELIEF_NONE);*/
    gtk_widget_show (button);
    gtk_signal_connect_object (GTK_OBJECT (button), "pressed",
                   GTK_SIGNAL_FUNC (e_calendar_on_next_pressed),
                   GTK_OBJECT (cal));
    gtk_signal_connect_object (GTK_OBJECT (button), "released",
                   GTK_SIGNAL_FUNC (e_calendar_on_next_released),
                   GTK_OBJECT (cal));
    arrow = gtk_arrow_new (GTK_ARROW_RIGHT, GTK_SHADOW_OUT);
    gtk_widget_show (arrow);
    gtk_container_add (GTK_CONTAINER (button), arrow);
    cal->next_item = gnome_canvas_item_new (canvas_group,
                        gnome_canvas_widget_get_type (),
                        "widget", button,
                        NULL);

    cal->min_rows = 1;
    cal->min_cols = 1;
    cal->max_rows = -1;
    cal->max_cols = -1;

    cal->timeout_id = 0;
}


/**
 * e_calendar_new:
 * @Returns: a new #ECalendar.
 *
 * Creates a new #ECalendar.
 **/
GtkWidget *
e_calendar_new          (void)
{
    GtkWidget *cal;

    cal = gtk_type_new (e_calendar_get_type ());

    return cal;
}


static void
e_calendar_destroy      (GtkObject *object)
{
    ECalendar *cal;

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

    cal = E_CALENDAR (object);

    if (cal->timeout_id != 0) {
        gtk_timeout_remove (cal->timeout_id);
        cal->timeout_id = 0;
    }
}


static void
e_calendar_realize (GtkWidget *widget)
{
    (*GTK_WIDGET_CLASS (parent_class)->realize) (widget);
}


static void
e_calendar_style_set        (GtkWidget  *widget,
                 GtkStyle   *previous_style)
{

    if (GTK_WIDGET_CLASS (parent_class)->style_set)
        (*GTK_WIDGET_CLASS (parent_class)->style_set) (widget,
                                   previous_style);
}


static void
e_calendar_size_request     (GtkWidget      *widget,
                 GtkRequisition *requisition)
{
    ECalendar *cal;
    GtkStyle *style;
    gint col_width, row_height, width, height;
    gboolean today_button_shown, none_button_shown;
    gint buttons_shown = 0, button_height, button_width, buttons_width;
    GtkRequisition today_button_requisition = { 0 };
    GtkRequisition none_button_requisition = { 0 };
    gint today_button_width = 0, today_button_height = 0;
    gint none_button_width = 0, none_button_height = 0;

    cal = E_CALENDAR (widget);
    style = GTK_WIDGET (cal)->style;

    gtk_object_get (GTK_OBJECT (cal->calitem),
            "row_height", &row_height,
            "column_width", &col_width,
            NULL);

    height = row_height * cal->min_rows;
    width = col_width * cal->min_cols;

    /* Add on space for line & button if shown. */
    today_button_shown = GTK_WIDGET_VISIBLE (cal->today_button);
    none_button_shown = GTK_WIDGET_VISIBLE (cal->none_button);

    if (today_button_shown || none_button_shown) {
        /* Note that we use the buttons' requisition fields directly
           since we want the sizes without any usize modification. */
        if (today_button_shown) {
            gtk_widget_size_request (cal->today_button,
                         &today_button_requisition);
            today_button_width = cal->today_button->requisition.width;
            today_button_height = cal->today_button->requisition.height;
            buttons_shown++;
        }
        if (none_button_shown) {
            gtk_widget_size_request (cal->none_button,
                         &none_button_requisition);
            none_button_width = cal->none_button->requisition.width;
            none_button_height = cal->none_button->requisition.height;
            buttons_shown++;
        }

        button_height = MAX (today_button_height, none_button_height);
        height += E_CALENDAR_YPAD_ABOVE_LOWER_BUTTONS + button_height
            + E_CALENDAR_YPAD_BELOW_LOWER_BUTTONS;

        button_width = MAX (today_button_width, none_button_width);
        button_width += E_CALENDAR_IXPAD_BUTTONS;
        buttons_width = buttons_shown * button_width
            + (buttons_shown - 1) * E_CALENDAR_XPAD_BUTTONS;

        width = MAX (width, buttons_width);
    }

    requisition->width = width + style->klass->xthickness * 2;
    requisition->height = height + style->klass->ythickness * 2;
}


static void
e_calendar_size_allocate    (GtkWidget  *widget,
                 GtkAllocation  *allocation)
{
    ECalendar *cal;
    GdkFont *font;
    gdouble old_x2, old_y2, new_x2, new_y2;
    gdouble buttons_x1, buttons_y1;
    gdouble button_width, button_height;
    gdouble buttons_width = 0, buttons_height = 0;
    gdouble xthickness, ythickness, arrow_button_size;
    gboolean today_button_shown, none_button_shown;
    gint buttons_shown = 0;
    GtkRequisition today_button_requisition = { 0 };
    GtkRequisition none_button_requisition = { 0 };
    gint today_button_width = 0, today_button_height = 0;
    gint none_button_width = 0, none_button_height = 0;

    cal = E_CALENDAR (widget);
    font = widget->style->font;
    xthickness = widget->style->klass->xthickness;
    ythickness = widget->style->klass->ythickness;

    (*GTK_WIDGET_CLASS (parent_class)->size_allocate) (widget, allocation);

    /* Set the scroll region to its allocated size, if changed. */
    gnome_canvas_get_scroll_region (GNOME_CANVAS (cal),
                    NULL, NULL, &old_x2, &old_y2);
    new_x2 = widget->allocation.width - 1;
    new_y2 = widget->allocation.height - 1;
    if (old_x2 != new_x2 || old_y2 != new_y2)
        gnome_canvas_set_scroll_region (GNOME_CANVAS (cal),
                        0, 0, new_x2, new_y2);

    /* Set the positions of the Today & None buttons if shown. */
    today_button_shown = GTK_WIDGET_VISIBLE (cal->today_button);
    none_button_shown = GTK_WIDGET_VISIBLE (cal->none_button);

    if (today_button_shown || none_button_shown) {
        if (today_button_shown) {
            gtk_widget_size_request (cal->today_button,
                         &today_button_requisition);
            today_button_width = cal->today_button->requisition.width;
            today_button_height = cal->today_button->requisition.height;
            buttons_shown++;
        }
        if (none_button_shown) {
            gtk_widget_size_request (cal->none_button,
                         &none_button_requisition);
            none_button_width = cal->none_button->requisition.width;
            none_button_height = cal->none_button->requisition.height;
            buttons_shown++;
        }

        button_height = MAX (today_button_height, none_button_height);
        buttons_height = E_CALENDAR_YPAD_ABOVE_LOWER_BUTTONS
            + button_height + E_CALENDAR_YPAD_BELOW_LOWER_BUTTONS;

        button_width = MAX (today_button_width, none_button_width);
        button_width += E_CALENDAR_IXPAD_BUTTONS;
        buttons_width = buttons_shown * button_width
            + (buttons_shown - 1) * E_CALENDAR_XPAD_BUTTONS;

        buttons_x1 = (new_x2 + 1 - buttons_width) / 2;
        buttons_x1 = MAX (0, buttons_x1);
            
        buttons_y1 = new_y2 + 1 - E_CALENDAR_YPAD_BELOW_LOWER_BUTTONS
            - button_height - ythickness;
        buttons_y1 = MAX (0, buttons_y1);

        gnome_canvas_item_set (cal->today_button_item,
                       "x", buttons_x1,
                       "y", buttons_y1,
                       "width", (gdouble) button_width,
                       "height", (gdouble) button_height,
                       NULL);

        if (today_button_shown)
            buttons_x1 += button_width + E_CALENDAR_XPAD_BUTTONS;

        gnome_canvas_item_set (cal->none_button_item,
                       "x", buttons_x1,
                       "y", buttons_y1,
                       "width", (gdouble) button_width,
                       "height", (gdouble) button_height,
                       NULL);
    }

    /* Take off space for line & buttons if shown. */
    gnome_canvas_item_set (GNOME_CANVAS_ITEM (cal->calitem),
                   "x1", 0.0,
                   "y1", 0.0,
                   "x2", new_x2,
                   "y2", new_y2,
                   "buttons_space", buttons_height,
                   NULL);


    /* Position the arrow buttons. */
    arrow_button_size = font->ascent + font->descent
        + E_CALENDAR_ITEM_YPAD_ABOVE_MONTH_NAME
        + E_CALENDAR_ITEM_YPAD_BELOW_MONTH_NAME
        - E_CALENDAR_ARROW_BUTTON_Y_PAD * 2;

    gnome_canvas_item_set (cal->prev_item,
                   "x", xthickness * 2
                   + E_CALENDAR_ARROW_BUTTON_X_PAD,
                   "y", ythickness * 2
                   + E_CALENDAR_ARROW_BUTTON_Y_PAD,
                   "width", arrow_button_size,
                   "height", arrow_button_size,
                   NULL);

    gnome_canvas_item_set (cal->next_item,
                   "x", new_x2 + 1 - xthickness * 2
                   - E_CALENDAR_ARROW_BUTTON_X_PAD
                   - arrow_button_size,
                   "y", ythickness * 2
                   + E_CALENDAR_ARROW_BUTTON_Y_PAD,
                   "width", arrow_button_size,
                   "height", arrow_button_size,
                   NULL);
}


static void
e_calendar_draw         (GtkWidget  *widget,
                 GdkRectangle   *area)
{
    ECalendar *cal;

    cal = E_CALENDAR (widget);

    (*GTK_WIDGET_CLASS (parent_class)->draw) (widget, area);

    /* GnomeCanvas bug workaround to draw the GnomeCanvasWidgets. */
#if 0
    (*GTK_WIDGET_CLASS (grandparent_class)->draw) (widget, area);
#endif
}


static gint
e_calendar_focus_in     (GtkWidget  *widget,
                 GdkEventFocus  *event)
{
    return FALSE;
}


static gint
e_calendar_focus_out        (GtkWidget  *widget,
                 GdkEventFocus  *event)
{
    return FALSE;
}


static gint
e_calendar_key_press        (GtkWidget  *widget,
                 GdkEventKey    *event)
{
    return FALSE;
}


void
e_calendar_set_minimum_size (ECalendar  *cal,
                 gint        rows,
                 gint        cols)
{
    g_return_if_fail (E_IS_CALENDAR (cal));

    cal->min_rows = rows;
    cal->min_cols = cols;

    gnome_canvas_item_set (GNOME_CANVAS_ITEM (cal->calitem),
                   "minimum_rows", rows,
                   "minimum_columns", cols,
                   NULL);

    gtk_widget_queue_resize (GTK_WIDGET (cal));
}


void
e_calendar_set_maximum_size (ECalendar  *cal,
                 gint        rows,
                 gint        cols)
{
    g_return_if_fail (E_IS_CALENDAR (cal));

    cal->max_rows = rows;
    cal->max_cols = cols;

    gnome_canvas_item_set (GNOME_CANVAS_ITEM (cal->calitem),
                   "maximum_rows", rows,
                   "maximum_columns", cols,
                   NULL);

    gtk_widget_queue_resize (GTK_WIDGET (cal));
}


/* Returns the border size on each side of the month displays. */
void
e_calendar_get_border_size  (ECalendar  *cal,
                 gint       *top,
                 gint       *bottom,
                 gint       *left,
                 gint       *right)
{
    GtkStyle *style;

    g_return_if_fail (E_IS_CALENDAR (cal));

    style = GTK_WIDGET (cal)->style;

    if (style) {
        *top    = style->klass->ythickness;
        *bottom = style->klass->ythickness
            + cal->calitem->buttons_space;
        *left   = style->klass->xthickness;
        *right  = style->klass->xthickness;
    } else {
        *top = *bottom = *left = *right = 0;
    }
}


static void
e_calendar_on_prev_pressed  (ECalendar  *cal)
{
    e_calendar_start_auto_move (cal, FALSE);
}


static void
e_calendar_on_next_pressed  (ECalendar  *cal)
{
    e_calendar_start_auto_move (cal, TRUE);
}


static void
e_calendar_start_auto_move  (ECalendar  *cal,
                 gboolean    moving_forward)
{
    ECalendarItem *calitem;
    gint offset;

    if (cal->timeout_id == 0) {
        cal->timeout_id = g_timeout_add (E_CALENDAR_AUTO_MOVE_TIMEOUT,
                         e_calendar_auto_move_handler,
                         cal);
    }
    cal->timeout_delay = E_CALENDAR_AUTO_MOVE_TIMEOUT_DELAY;
    cal->moving_forward = moving_forward;

    calitem = cal->calitem;
    offset = cal->moving_forward ? 1 : -1;
    e_calendar_item_set_first_month (calitem, calitem->year,
                     calitem->month + offset);
}


static gboolean
e_calendar_auto_move_handler    (gpointer    data)
{
    ECalendar *cal;
    ECalendarItem *calitem;
    gint offset;

    g_return_val_if_fail (E_IS_CALENDAR (data), FALSE);

    cal = E_CALENDAR (data);
    calitem = cal->calitem;

    GDK_THREADS_ENTER ();

    if (cal->timeout_delay > 0) {
        cal->timeout_delay--;
    } else {
        offset = cal->moving_forward ? 1 : -1;
        e_calendar_item_set_first_month (calitem, calitem->year,
                         calitem->month + offset);
    }

    GDK_THREADS_LEAVE ();
    return TRUE;
}


static void
e_calendar_on_prev_released (ECalendar  *cal)
{
    e_calendar_stop_auto_move (cal);
}


static void
e_calendar_on_next_released (ECalendar  *cal)
{
    e_calendar_stop_auto_move (cal);
}


static void
e_calendar_stop_auto_move   (ECalendar  *cal)
{
    if (cal->timeout_id != 0) {
        gtk_timeout_remove (cal->timeout_id);
        cal->timeout_id = 0;
    }
}


/* Set which, if any, of the buttons to show beneath the month displays.
   You must connect to the button's clicked signal and perform the
   required action yourself. */
void
e_calendar_set_buttons  (ECalendar  *cal,
             gboolean    show_today_button,
             gboolean    show_none_button)
{
    if (show_today_button) {
        gtk_widget_show (cal->today_button);
        gnome_canvas_item_show (cal->today_button_item);
    } else {
        gtk_widget_hide (cal->today_button);
        gnome_canvas_item_hide (cal->today_button_item);
    }

    if (show_none_button) {
        gtk_widget_show (cal->none_button);
        gnome_canvas_item_show (cal->none_button_item);
    } else {
        gtk_widget_hide (cal->none_button);
        gnome_canvas_item_hide (cal->none_button_item);
    }
}


static gint
e_calendar_drag_motion (GtkWidget      *widget,
            GdkDragContext *context,
            gint            x,
            gint            y,
            guint           time)
{
    ECalendar *cal;

    g_return_val_if_fail (E_IS_CALENDAR (widget), FALSE);

    cal = E_CALENDAR (widget);

#if 0
    g_print ("In e_calendar_drag_motion\n");
#endif

    return FALSE;
}


static void
e_calendar_drag_leave (GtkWidget      *widget,
               GdkDragContext *context,
               guint           time)
{
    ECalendar *cal;

    g_return_if_fail (E_IS_CALENDAR (widget));

    cal = E_CALENDAR (widget);

#if 0
    g_print ("In e_calendar_drag_leave\n");
#endif
}