/*
 * e-canvas-background.c - background color for canvas.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the program; if not, see <http://www.gnu.org/licenses/>
 *
 *
 * Authors:
 *		Chris Lahey <clahey@ximian.com>
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 */

#include <config.h>

#include <math.h>
#include <stdio.h>
#include <string.h>

#include <gdk/gdkkeysyms.h>
#include <gtk/gtk.h>

#include <glib/gi18n.h>
#include "e-util/e-util.h"
#include "misc/e-canvas.h"
#include "misc/e-canvas-utils.h"
#include "misc/e-hsv-utils.h"

#include "e-canvas-background.h"

/* workaround for avoiding API broken */
#define ecb_get_type e_canvas_background_get_type
G_DEFINE_TYPE (
	ECanvasBackground,
	ecb,
	GNOME_TYPE_CANVAS_ITEM)

#define d(x)

struct _ECanvasBackgroundPrivate {
	guint rgba;		/* Fill color, RGBA */
	GdkColor color;		/* Fill color */
	GdkBitmap *stipple;	/* Stipple for fill */
	GdkGC *gc;			/* GC for filling */
	gdouble x1;
	gdouble x2;
	gdouble y1;
	gdouble y2;

	guint needs_redraw : 1;
};

enum {
	STYLE_SET,
	LAST_SIGNAL
};

static guint ecb_signals [LAST_SIGNAL] = { 0, };

enum {
	PROP_0,
	PROP_FILL_COLOR,
	PROP_FILL_COLOR_GDK,
	PROP_FILL_COLOR_RGBA,
	PROP_FILL_STIPPLE,
	PROP_X1,
	PROP_X2,
	PROP_Y1,
	PROP_Y2
};

static void
get_color (ECanvasBackground *ecb)
{
	GnomeCanvasItem *item = GNOME_CANVAS_ITEM (ecb);
	ecb->priv->color.pixel = gnome_canvas_get_color_pixel (item->canvas,
		GNOME_CANVAS_COLOR (ecb->priv->color.red >> 8,
				   ecb->priv->color.green>> 8,
				   ecb->priv->color.blue>> 8));
}

static void
ecb_bounds (GnomeCanvasItem *item, gdouble *x1, gdouble *y1, gdouble *x2, gdouble *y2)
{
	gdouble   i2c [6];
	ArtPoint c1, c2, i1, i2;
	ECanvasBackground *ecb = E_CANVAS_BACKGROUND (item);

	/* Wrong BBox's are the source of redraw nightmares */

	gnome_canvas_item_i2c_affine (GNOME_CANVAS_ITEM (ecb), i2c);

	i1.x = ecb->priv->x1;
	i1.y = ecb->priv->y1;
	i2.x = ecb->priv->x2;
	i2.y = ecb->priv->y2;
	art_affine_point (&c1, &i1, i2c);
	art_affine_point (&c2, &i2, i2c);

	if (ecb->priv->x1 < 0)
		c1.x = -(gdouble)UINT_MAX;

	if (ecb->priv->y1 < 0)
		c1.y = -(gdouble)UINT_MAX;

	if (ecb->priv->x2 < 0)
		c2.x = (gdouble)UINT_MAX;

	if (ecb->priv->y2 < 0)
		c2.y = (gdouble)UINT_MAX;

	*x1 = c1.x;
	*y1 = c1.y;
	*x2 = c2.x + 1;
	*y2 = c2.y + 1;
}

/*
 * GnomeCanvasItem::update method
 */
static void
ecb_update (GnomeCanvasItem *item, gdouble *affine, ArtSVP *clip_path, gint flags)
{
	ArtPoint o1, o2;
	ECanvasBackground *ecb = E_CANVAS_BACKGROUND (item);

	if (GNOME_CANVAS_ITEM_CLASS (ecb_parent_class)->update)
		GNOME_CANVAS_ITEM_CLASS (ecb_parent_class)->update (item, affine, clip_path, flags);

	o1.x = item->x1;
	o1.y = item->y1;
	o2.x = item->x2;
	o2.y = item->y2;

	ecb_bounds (item, &item->x1, &item->y1, &item->x2, &item->y2);
	if (item->x1 != o1.x ||
	    item->y1 != o1.y ||
	    item->x2 != o2.x ||
	    item->y2 != o2.y) {
		gnome_canvas_request_redraw (item->canvas, o1.x, o1.y, o2.x, o2.y);
		ecb->priv->needs_redraw = 1;
	}

	if (ecb->priv->needs_redraw) {
		gnome_canvas_request_redraw (item->canvas, item->x1, item->y1,
					     item->x2, item->y2);
		ecb->priv->needs_redraw = 0;
	}
}

/* Sets the stipple pattern for the text */
static void
set_stipple (ECanvasBackground *ecb, GdkBitmap *stipple, gint use_value)
{
	if (use_value) {
		if (ecb->priv->stipple)
			g_object_unref (ecb->priv->stipple);

		ecb->priv->stipple = stipple;
		if (stipple)
			g_object_ref (stipple);
	}

	if (ecb->priv->gc) {
		if (stipple) {
			gdk_gc_set_stipple (ecb->priv->gc, stipple);
			gdk_gc_set_fill (ecb->priv->gc, GDK_STIPPLED);
		} else
			gdk_gc_set_fill (ecb->priv->gc, GDK_SOLID);
	}
}

static void
ecb_dispose (GObject *object)
{
	ECanvasBackground *ecb = E_CANVAS_BACKGROUND (object);

	if (ecb->priv) {
		if (ecb->priv->stipple)
			g_object_unref (ecb->priv->stipple);
		ecb->priv->stipple = NULL;

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

	if (G_OBJECT_CLASS (ecb_parent_class)->dispose)
                G_OBJECT_CLASS (ecb_parent_class)->dispose (object);
}

static void
ecb_set_property (GObject *object,
		  guint prop_id,
		  const GValue *value,
		  GParamSpec *pspec)
{
	GnomeCanvasItem *item;
	ECanvasBackground *ecb;

	GdkColor color = { 0, 0, 0, 0, };
	GdkColor *pcolor;
	gboolean color_changed = FALSE;

	item = GNOME_CANVAS_ITEM (object);
	ecb = E_CANVAS_BACKGROUND (object);

	switch (prop_id) {
	case PROP_FILL_COLOR:
		if (g_value_get_string (value))
			gdk_color_parse (g_value_get_string (value), &color);

		ecb->priv->rgba = ((color.red & 0xff00) << 16 |
				   (color.green & 0xff00) << 8 |
				   (color.blue & 0xff00) |
				   0xff);
		color_changed = TRUE;
		break;

	case PROP_FILL_COLOR_GDK:
		pcolor = g_value_get_boxed (value);
		if (pcolor) {
			color = *pcolor;
		}

		ecb->priv->rgba = ((color.red & 0xff00) << 16 |
				   (color.green & 0xff00) << 8 |
				   (color.blue & 0xff00) |
				   0xff);
		color_changed = TRUE;
		break;

        case PROP_FILL_COLOR_RGBA:
		ecb->priv->rgba = g_value_get_uint (value);
		color.red = ((ecb->priv->rgba >> 24) & 0xff) * 0x101;
		color.green = ((ecb->priv->rgba >> 16) & 0xff) * 0x101;
		color.blue = ((ecb->priv->rgba >> 8) & 0xff) * 0x101;
		color_changed = TRUE;
		break;

	case PROP_FILL_STIPPLE:
		set_stipple (ecb, g_value_get_object (value), TRUE);
		break;

	case PROP_X1:
		ecb->priv->x1 = g_value_get_double (value);
		break;
	case PROP_X2:
		ecb->priv->x2 = g_value_get_double (value);
		break;
	case PROP_Y1:
		ecb->priv->y1 = g_value_get_double (value);
		break;
	case PROP_Y2:
		ecb->priv->y2 = g_value_get_double (value);
		break;
	}

	if (color_changed) {
		ecb->priv->color = color;

		if (item->flags & GNOME_CANVAS_ITEM_REALIZED) {
			get_color (ecb);
			if (!item->canvas->aa) {
				gdk_gc_set_foreground (ecb->priv->gc, &ecb->priv->color);
			}
		}
	}

	ecb->priv->needs_redraw = 1;
	gnome_canvas_item_request_update (GNOME_CANVAS_ITEM (ecb));
}

static void
ecb_get_property (GObject *object,
		  guint prop_id,
		  GValue *value,
		  GParamSpec *pspec)
{
	ECanvasBackground *ecb;

	ecb = E_CANVAS_BACKGROUND (object);

	switch (prop_id) {
	case PROP_FILL_COLOR_GDK:
		g_value_set_boxed (value, gdk_color_copy (&ecb->priv->color));
		break;
        case PROP_FILL_COLOR_RGBA:
		g_value_set_uint (value, ecb->priv->rgba);
		break;
	case PROP_FILL_STIPPLE:
		g_value_set_object (value, ecb->priv->stipple);
		break;
	case PROP_X1:
		g_value_set_double (value, ecb->priv->x1);
		break;
	case PROP_X2:
		g_value_set_double (value, ecb->priv->x2);
		break;
	case PROP_Y1:
		g_value_set_double (value, ecb->priv->y1);
		break;
	case PROP_Y2:
		g_value_set_double (value, ecb->priv->y2);
		break;
	default:
		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
		break;
	}
}

static void
ecb_init (ECanvasBackground *ecb)
{
	ecb->priv               = g_new (ECanvasBackgroundPrivate, 1);

	ecb->priv->color.pixel  = 0;
	ecb->priv->color.red    = 0;
	ecb->priv->color.green  = 0;
	ecb->priv->color.blue   = 0;
	ecb->priv->stipple      = NULL;
	ecb->priv->gc           = NULL;
	ecb->priv->x1           = -1.0;
	ecb->priv->x2           = -1.0;
	ecb->priv->y1           = -1.0;
	ecb->priv->y2           = -1.0;
}

static void
ecb_realize (GnomeCanvasItem *item)
{
	ECanvasBackground *ecb = E_CANVAS_BACKGROUND (item);
	GdkWindow *bin_window;

	if (GNOME_CANVAS_ITEM_CLASS (ecb_parent_class)->realize)
                GNOME_CANVAS_ITEM_CLASS (ecb_parent_class)->realize (item);

	bin_window = gtk_layout_get_bin_window (GTK_LAYOUT (item->canvas));

	ecb->priv->gc = gdk_gc_new (bin_window);
	get_color (ecb);
	if (!item->canvas->aa)
		gdk_gc_set_foreground (ecb->priv->gc, &ecb->priv->color);

	set_stipple (ecb, NULL, FALSE);

	ecb->priv->needs_redraw = 1;
	gnome_canvas_item_request_update (GNOME_CANVAS_ITEM (ecb));
}

static void
ecb_unrealize (GnomeCanvasItem *item)
{
	ECanvasBackground *ecb = E_CANVAS_BACKGROUND (item);

	g_object_unref (ecb->priv->gc);
	ecb->priv->gc = NULL;

	if (GNOME_CANVAS_ITEM_CLASS (ecb_parent_class)->unrealize)
                GNOME_CANVAS_ITEM_CLASS (ecb_parent_class)->unrealize (item);
}

static void
ecb_draw (GnomeCanvasItem *item,
          GdkDrawable *drawable,
          gint x,
          gint y,
          gint width,
          gint height)
{
	ECanvasBackground *ecb = E_CANVAS_BACKGROUND (item);
	gint x1, x2, y1, y2;
	gdouble i2c [6];
	ArtPoint upper_left, lower_right, ecb_base_point;

	/*
	 * Find out our real position after grouping
	 */
	gnome_canvas_item_i2c_affine (item, i2c);
	ecb_base_point.x = ecb->priv->x1;
	ecb_base_point.y = ecb->priv->y1;
	art_affine_point (&upper_left, &ecb_base_point, i2c);

	ecb_base_point.x = ecb->priv->x2;
	ecb_base_point.y = ecb->priv->y2;
	art_affine_point (&lower_right, &ecb_base_point, i2c);

	x1 = 0;
	y1 = 0;
	x2 = width;
	y2 = height;
	if (ecb->priv->x1 >= 0 && upper_left.x > x1)
		x1 = upper_left.x;
	if (ecb->priv->y1 >= 0 && upper_left.y > y1)
		y1 = upper_left.y;
	if (ecb->priv->x2 >= 0 && lower_right.x < x2)
		x2 = lower_right.x;
	if (ecb->priv->y2 >= 0 && lower_right.y < y2)
		y2 = lower_right.y;

	gdk_draw_rectangle (drawable, ecb->priv->gc, TRUE,
			    x1, y1, x2 - x1, y2 - y1);
}

static double
ecb_point (GnomeCanvasItem *item, gdouble x, gdouble y, gint cx, gint cy,
	   GnomeCanvasItem **actual_item)
{
	ECanvasBackground *ecb = E_CANVAS_BACKGROUND (item);

	if (ecb->priv->x1 >= 0 && ecb->priv->x1 > x)
		return 1.0;
	if (ecb->priv->x2 >= 0 && ecb->priv->x2 < x)
		return 1.0;
	if (ecb->priv->y1 >= 0 && ecb->priv->y1 > y)
		return 1.0;
	if (ecb->priv->y2 >= 0 && ecb->priv->y2 < y)
		return 1.0;
	*actual_item = item;

	return 0.0;
}

static void
ecb_style_set (ECanvasBackground *ecb,
               GtkStyle *previous_style)
{
	GnomeCanvasItem *item = GNOME_CANVAS_ITEM (ecb);
	GtkStyle *style;

	style = gtk_widget_get_style (GTK_WIDGET (item->canvas));

	if (gtk_widget_get_realized (GTK_WIDGET (item->canvas))) {
		gdk_gc_set_foreground (
			ecb->priv->gc, &style->base[GTK_STATE_NORMAL]);
		gnome_canvas_item_request_update (GNOME_CANVAS_ITEM (ecb));
	}
}

static void
ecb_class_init (ECanvasBackgroundClass *ecb_class)
{
	GnomeCanvasItemClass *item_class = GNOME_CANVAS_ITEM_CLASS (ecb_class);
	GObjectClass *object_class = G_OBJECT_CLASS (ecb_class);

	object_class->dispose       = ecb_dispose;
	object_class->set_property  = ecb_set_property;
	object_class->get_property  = ecb_get_property;

	item_class->update          = ecb_update;
	item_class->realize         = ecb_realize;
	item_class->unrealize       = ecb_unrealize;
	item_class->draw            = ecb_draw;
	item_class->point           = ecb_point;

	ecb_class->style_set	    = ecb_style_set;

	g_object_class_install_property (object_class, PROP_FILL_COLOR,
					 g_param_spec_string ("fill_color",
							      "Fill color",
							      "Fill color",
							      NULL,
							      G_PARAM_READWRITE));

	g_object_class_install_property (object_class, PROP_FILL_COLOR_GDK,
					 g_param_spec_boxed ("fill_color_gdk",
							     "GDK fill color",
							     "GDK fill color",
							     GDK_TYPE_COLOR,
							     G_PARAM_READWRITE));

	g_object_class_install_property (object_class, PROP_FILL_COLOR_RGBA,
					 g_param_spec_uint ("fill_color_rgba",
							    "GDK fill color",
							    "GDK fill color",
							    0, G_MAXUINT, 0,
							    G_PARAM_READWRITE));

	g_object_class_install_property (object_class, PROP_FILL_STIPPLE,
					 g_param_spec_object ("fill_stipple",
							      "Fill stipple",
							      "Fill stipple",
							      GDK_TYPE_WINDOW,
							      G_PARAM_READWRITE));

	g_object_class_install_property (object_class, PROP_X1,
					 g_param_spec_double ("x1",
							      "X1",
							      "X1",
							      0.0, G_MAXDOUBLE, 0.0,
							      G_PARAM_READWRITE));

	g_object_class_install_property (object_class, PROP_X2,
					 g_param_spec_double ("x2",
							      "X2",
							      "X2",
							      0.0, G_MAXDOUBLE, 0.0,
							      G_PARAM_READWRITE));

	g_object_class_install_property (object_class, PROP_Y1,
					 g_param_spec_double ("y1",
							      "Y1",
							      "Y1",
							      0.0, G_MAXDOUBLE, 0.0,
							      G_PARAM_READWRITE));

	g_object_class_install_property (object_class, PROP_Y2,
					 g_param_spec_double ("y2",
							      "Y2",
							      "Y2",
							      0.0, G_MAXDOUBLE, 0.0,
							      G_PARAM_READWRITE));
	ecb_signals [STYLE_SET] =
		g_signal_new ("style_set",
			      G_OBJECT_CLASS_TYPE (object_class),
			      G_SIGNAL_RUN_LAST,
			      G_STRUCT_OFFSET (ECanvasBackgroundClass, style_set),
			      NULL, NULL,
			      g_cclosure_marshal_VOID__OBJECT,
			      G_TYPE_NONE, 1, GTK_TYPE_STYLE);
}