/* $Id$ */
/*
 * Copyright (c) 2007 Nick Schermer <nick@xfce.org>
 *
 * 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
 */

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

#ifdef HAVE_TIME_H
#include <time.h>
#endif
#ifdef HAVE_MATH_H
#include <math.h>
#endif

#ifndef M_PI
#define M_PI 3.141592654
#endif

#include <gtk/gtk.h>
#include <cairo/cairo.h>

#include "clock.h"
#include "clock-binary.h"



/* class functions */
static void      xfce_clock_binary_finalize      (GObject              *object);
static void      xfce_clock_binary_set_property  (GObject              *object,
                                                  guint                 prop_id,
                                                  const GValue         *value,
                                                  GParamSpec           *pspec);
static void      xfce_clock_binary_get_property  (GObject              *object,
                                                  guint                 prop_id,
                                                  GValue               *value,
                                                  GParamSpec           *pspec);
static void      xfce_clock_binary_size_request  (GtkWidget            *widget,
                                                  GtkRequisition       *requisition);
static gboolean  xfce_clock_binary_expose_event  (GtkWidget            *widget,
                                                  GdkEventExpose       *event);


enum
{
    PROP_0,
    PROP_SHOW_SECONDS,
    PROP_TRUE_BINARY
};

struct _XfceClockBinaryClass
{
    GtkImageClass __parent__;
};

struct _XfceClockBinary
{
    GtkImage  __parent__;

    /* whether we draw seconds */
    guint     show_seconds : 1;

    /* if this is a true binary clock */
    guint     true_binary : 1;
};



G_DEFINE_TYPE (XfceClockBinary, xfce_clock_binary, GTK_TYPE_IMAGE);



static void
xfce_clock_binary_class_init (XfceClockBinaryClass *klass)
{
    GObjectClass   *gobject_class;
    GtkWidgetClass *gtkwidget_class;

    gobject_class = G_OBJECT_CLASS (klass);
    gobject_class->finalize = xfce_clock_binary_finalize;
    gobject_class->set_property = xfce_clock_binary_set_property;
    gobject_class->get_property = xfce_clock_binary_get_property;

    gtkwidget_class = GTK_WIDGET_CLASS (klass);
    gtkwidget_class->size_request = xfce_clock_binary_size_request;
    gtkwidget_class->expose_event = xfce_clock_binary_expose_event;

    /**
     * Whether we display seconds
     **/
    g_object_class_install_property (gobject_class,
                                     PROP_SHOW_SECONDS,
                                     g_param_spec_boolean ("show-seconds", "show-seconds", "show-seconds",
                                                           FALSE, PANEL_PARAM_READWRITE));

    /**
     * Whether this is a true binary clock
     **/
    g_object_class_install_property (gobject_class,
                                     PROP_TRUE_BINARY,
                                     g_param_spec_boolean ("true-binary", "true-binary", "true-binary",
                                                           FALSE, PANEL_PARAM_READWRITE));
}



static void
xfce_clock_binary_init (XfceClockBinary *binary)
{
    /* init */
    binary->show_seconds = FALSE;
    binary->true_binary = FALSE;
}



static void
xfce_clock_binary_finalize (GObject *object)
{
    (*G_OBJECT_CLASS (xfce_clock_binary_parent_class)->finalize) (object);
}



static void
xfce_clock_binary_set_property (GObject      *object,
                                guint         prop_id,
                                const GValue *value,
                                GParamSpec   *pspec)
{
    XfceClockBinary *binary = XFCE_CLOCK_BINARY (object);

    switch (prop_id)
    {
        case PROP_SHOW_SECONDS:
            binary->show_seconds = g_value_get_boolean (value);
            break;

        case PROP_TRUE_BINARY:
            binary->true_binary = g_value_get_boolean (value);
            break;

        default:
            G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
            break;
    }
}



static void
xfce_clock_binary_get_property (GObject    *object,
                                guint       prop_id,
                                GValue     *value,
                                GParamSpec *pspec)
{
    XfceClockBinary *binary = XFCE_CLOCK_BINARY (object);

    switch (prop_id)
    {
        case PROP_SHOW_SECONDS:
            g_value_set_boolean (value, binary->show_seconds);
            break;

        case PROP_TRUE_BINARY:
            g_value_set_boolean (value, binary->true_binary);
            break;

        default:
            G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
            break;
    }
}



static void
xfce_clock_binary_size_request (GtkWidget      *widget,
                                GtkRequisition *requisition)
{
    gint             width, height;
    gdouble          ratio;
    XfceClockBinary *binary = XFCE_CLOCK_BINARY (widget);

    /* get the current widget size */
    gtk_widget_get_size_request (widget, &width, &height);

    /* ratio of the clock */
    if (binary->true_binary)
    {
        ratio = binary->show_seconds ? 2.0 : 3.0;
    }
    else
    {
        ratio = binary->show_seconds ? 1.5 : 1.0;
    }

    /* set requisition based on the plugin orientation */
    if (width == -1)
    {
        requisition->height = height;
        requisition->width = height * ratio;
    }
    else
    {
        requisition->height = width / ratio;
        requisition->width = width;
    }
}



static gboolean
xfce_clock_binary_expose_event (GtkWidget      *widget,
                                GdkEventExpose *event)
{
    XfceClockBinary *binary = XFCE_CLOCK_BINARY (widget);
    gdouble          cw, ch, columns;
    gint             ticks, cells, decimal;
    gdouble          radius;
    gdouble          x, y;
    gint             i, j;
    gint             decimal_tb[] = {32, 16, 8, 4, 2, 1};
    gint             decimal_bcd[] = {80, 40, 20, 10, 8, 4, 2, 1};
    cairo_t         *cr;
    GdkColor         active, inactive;
    struct tm        tm;

    g_return_val_if_fail (XFCE_CLOCK_IS_BINARY (binary), FALSE);

    /* number of columns and cells */
    columns = binary->show_seconds ? 3.0 : 2.0;
    cells = binary->true_binary ? 6 : 8;

    /* cell width and height */
    if (binary->true_binary)
    {
        cw = widget->allocation.width / 6.0;
        ch = widget->allocation.height / columns;
    }
    else /* bcd clock */
    {
        cw = widget->allocation.width / columns / 2.0;
        ch = widget->allocation.height / 4.0;
    }

    /* arc radius */
    radius = MIN (cw, ch) / 2.0 * 0.7;

    /* get colors */
    inactive = widget->style->fg[GTK_STATE_NORMAL];
    active = widget->style->bg[GTK_STATE_SELECTED];

    /* get the cairo context */
    cr = gdk_cairo_create (widget->window);

    if (G_LIKELY (cr != NULL))
    {
        /* clip the drawing area */
        gdk_cairo_rectangle (cr, &event->area);
        cairo_clip (cr);
        
        /* get the current time */
        xfce_clock_util_get_localtime (&tm);

        /* walk the three or two time parts */
        for (i = 0; i < columns; i++)
        {
            /* get the time of this column */
            if (i == 0)
                ticks = tm.tm_hour;
            else if (i == 1)
                ticks = tm.tm_min;
            else
                ticks = tm.tm_sec;

            /* walk the binary columns */
            for (j = 0; j < cells; j++)
            {
                if (binary->true_binary)
                {
                    /* skip the columns we don't draw */
                    if (i == 0 && j == 0)
                        continue;

                    /* decimal representation of this cell */
                    decimal = decimal_tb[j];

                    /* center of the arc */
                    x = cw * (j + 0.5) + widget->allocation.x;
                    y = ch * (i + 0.5) + widget->allocation.y;
                }
                else /* bcd clock */
                {
                    /* skip the columns we don't draw */
                    if ((j == 0) || (i == 0 && j == 1))
                        continue;

                    /* decimal representation of this cell */
                    decimal = decimal_bcd[j];

                    /* center of the arc */
                    x = cw * (i * 2 + (j < 4 ? 0 : 1) + 0.5) + widget->allocation.x;
                    y = ch * ((j >= 4 ? j - 4 : j) + 0.5) + widget->allocation.y;
                }

                /* if this binary values 'fits' in the time */
                if (ticks >= decimal)
                {
                    /* extract the decimal value from the time */
                    ticks -= decimal;

                    /* set the active color */
                    gdk_cairo_set_source_color (cr, &active);
                }
                else
                {
                    /* set the inactive color */
                    gdk_cairo_set_source_color (cr, &inactive);
                }

                /* draw the arc */
                cairo_move_to (cr, x, y);
                cairo_arc (cr, x, y, radius, 0, 2 * M_PI);
                cairo_close_path (cr);

                /* fill the arc */
                cairo_fill (cr);
            }
        }

        /* cleanup */
        cairo_destroy (cr);
    }

    return FALSE;
}



GtkWidget *
xfce_clock_binary_new (void)
{
    return g_object_new (XFCE_CLOCK_TYPE_BINARY, NULL);
}



gboolean
xfce_clock_binary_update (gpointer user_data)
{
    GtkWidget *widget = GTK_WIDGET (user_data);

    /* update if the widget if visible */
    if (G_LIKELY (GTK_WIDGET_VISIBLE (widget)))
        gtk_widget_queue_draw (widget);

    return TRUE;
}