evolution/widgets/table/e-table-header-utils.c

/*
 * 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>
 *      Miguel de Icaza <miguel@ximian.com>
 *      Federico Mena-Quintero <federico@ximian.com>
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 */

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

#include <string.h> /* strlen() */

#include <gtk/gtk.h>

#include "e-util/e-unicode.h"

#include "e-table-defines.h"
#include "e-table-header-utils.h"

static PangoLayout *
build_header_layout (GtkWidget *widget,
                     const gchar *str)
{
	PangoLayout *layout;

	layout = gtk_widget_create_pango_layout (widget, str);

#ifdef FROB_FONT_DESC
	{
		PangoFontDescription *desc;
		desc = pango_font_description_copy (gtk_widget_get_style (widget)->font_desc);
		pango_font_description_set_size (desc,
						 pango_font_description_get_size (desc) * 1.2);

		pango_font_description_set_weight (desc, PANGO_WEIGHT_BOLD);
		pango_layout_set_font_description (layout, desc);

		pango_font_description_free (desc);
	}
#endif

	return layout;
}

/**
 * e_table_header_compute_height:
 * @ecol: Table column description.
 * @widget: The widget from which to build the PangoLayout.
 *
 * Computes the minimum height required for a table header button.
 *
 * Return value: The height of the button, in pixels.
 **/
gdouble
e_table_header_compute_height (ETableCol *ecol,
                               GtkWidget *widget)
{
	gint ythick;
	gint height;
	PangoLayout *layout;

	g_return_val_if_fail (ecol != NULL, -1);
	g_return_val_if_fail (E_IS_TABLE_COL (ecol), -1);
	g_return_val_if_fail (GTK_IS_WIDGET (widget), -1);

	ythick = gtk_widget_get_style (widget)->ythickness;

	layout = build_header_layout (widget, ecol->text);

	pango_layout_get_pixel_size (layout, NULL, &height);

	if (ecol->icon_name != NULL) {
		g_return_val_if_fail (ecol->pixbuf != NULL, -1);
		height = MAX (height, gdk_pixbuf_get_height (ecol->pixbuf));
	}

	height = MAX (height, MIN_ARROW_SIZE);

	height += 2 * (ythick + HEADER_PADDING);

	g_object_unref (layout);

	return height;
}

gdouble
e_table_header_width_extras (GtkStyle *style)
{
	g_return_val_if_fail (style != NULL, -1);

	return 2 * (style->xthickness + HEADER_PADDING);
}

/* Creates a pixmap that is a composite of a background color and the upper-left
 * corner rectangle of a pixbuf.
 */
#if 0
static GdkPixmap *
make_composite_pixmap (GdkDrawable *drawable,
                       GdkGC *gc,
                       GdkPixbuf *pixbuf,
                       GdkColor *bg,
                       gint width,
                       gint height,
                       gint dither_xofs,
                       gint dither_yofs)
{
	gint pwidth, pheight;
	GdkPixmap *pixmap;
	GdkPixbuf *tmp;
	gint color;

	pwidth = gdk_pixbuf_get_width (pixbuf);
	pheight = gdk_pixbuf_get_height (pixbuf);
	g_return_val_if_fail (width <= pwidth && height <= pheight, NULL);

	color = ((bg->red & 0xff00) << 8) |
		(bg->green & 0xff00) |
		((bg->blue & 0xff00) >> 8);

	if (width >= pwidth && height >= pheight) {
		tmp = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, width, height);
		if (!tmp)
			return NULL;

		gdk_pixbuf_composite_color (pixbuf, tmp,
					    0, 0,
					    width, height,
					    0, 0,
					    1.0, 1.0,
					    GDK_INTERP_NEAREST,
					    255,
					    0, 0,
					    16,
					    color, color);
	} else {
		gint x, y, rowstride;
		GdkPixbuf *fade;
		guchar *pixels;

		/* Do a nice fade of the pixbuf down and to the right */

		fade = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, width, height);
		if (!fade)
			return NULL;

		gdk_pixbuf_copy_area (pixbuf,
				      0, 0,
				      width, height,
				      fade,
				      0, 0);

		rowstride = gdk_pixbuf_get_rowstride (fade);
		pixels = gdk_pixbuf_get_pixels (fade);

		for (y = 0; y < height; y++) {
			guchar *p;
			gint yfactor;

			p = pixels + y * rowstride;

			if (height < pheight)
				yfactor = height - y;
			else
				yfactor = height;

			for (x = 0; x < width; x++) {
				gint xfactor;

				if (width < pwidth)
					xfactor = width - x;
				else
					xfactor = width;

				p[3] = ((gint) p[3] * xfactor * yfactor / (width * height));
				p += 4;
			}
		}

		tmp = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, width, height);
		if (!tmp) {
			g_object_unref (fade);
			return NULL;
		}

		gdk_pixbuf_composite_color (fade, tmp,
					    0, 0,
					    width, height,
					    0, 0,
					    1.0, 1.0,
					    GDK_INTERP_NEAREST,
					    255,
					    0, 0,
					    16,
					    color, color);

		g_object_unref (fade);
	}

	pixmap = gdk_pixmap_new (drawable, width, height, -1);
	gdk_draw_rgb_image_dithalign (pixmap, gc,
				      0, 0,
				      width, height,
				      GDK_RGB_DITHER_NORMAL,
				      gdk_pixbuf_get_pixels (tmp),
				      gdk_pixbuf_get_rowstride (tmp),
				      dither_xofs, dither_yofs);
	g_object_unref (tmp);

	return pixmap;
}
#endif

/**
 * e_table_header_draw_button:
 * @drawable: Destination drawable.
 * @ecol: Table column for the header information.
 * @style: Style to use for drawing the button.
 * @state: State of the table widget.
 * @widget: The table widget.
 * @x: Leftmost coordinate of the button.
 * @y: Topmost coordinate of the button.
 * @width: Width of the region to draw.
 * @height: Height of the region to draw.
 * @button_width: Width for the complete button.
 * @button_height: Height for the complete button.
 * @arrow: Arrow type to use as a sort indicator.
 *
 * Draws a button suitable for a table header.
 **/
void
e_table_header_draw_button (cairo_t *cr,
                            ETableCol *ecol,
                            GtkStyle *style,
                            GtkStateType state,
                            GtkWidget *widget,
                            gint x,
                            gint y,
                            gint width,
                            gint height,
                            gint button_width,
                            gint button_height,
                            ETableColArrow arrow)
{
	gint xthick, ythick;
	gint inner_x, inner_y;
	gint inner_width, inner_height;
	gint arrow_width = 0, arrow_height = 0;
	PangoLayout *layout;
	static gpointer g_label = NULL;

	g_return_if_fail (cr != NULL);
	g_return_if_fail (ecol != NULL);
	g_return_if_fail (E_IS_TABLE_COL (ecol));
	g_return_if_fail (style != NULL);
	g_return_if_fail (widget != NULL);
	g_return_if_fail (GTK_IS_WIDGET (widget));
	g_return_if_fail (button_width > 0 && button_height > 0);

	if (g_label == NULL) {
		GtkWidget *button = gtk_button_new_with_label("Hi");
		GtkWidget *window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
		gtk_container_add (GTK_CONTAINER (window), button);
		gtk_widget_ensure_style (window);
		gtk_widget_ensure_style (button);
		g_label = gtk_bin_get_child (GTK_BIN (button));
		g_object_add_weak_pointer (G_OBJECT (g_label), &g_label);
		gtk_widget_ensure_style (g_label);
		gtk_widget_realize (g_label);
	}

	cairo_save (cr);
	gdk_cairo_set_source_color (
		cr, &gtk_widget_get_style (GTK_WIDGET (g_label))->fg[state]);

	xthick = style->xthickness;
	ythick = style->ythickness;

	/* Button bevel */

	gtk_paint_box (style, cr, state, GTK_SHADOW_OUT,
		       widget, "button",
		       x, y, button_width, button_height);

	/* Inside area */

	inner_width = button_width - 2 * (xthick + HEADER_PADDING);
	inner_height = button_height - 2 * (ythick + HEADER_PADDING);

	if (inner_width < 1 || inner_height < 1) {
		cairo_restore (cr);
		return; /* nothing fits */
	}

	inner_x = x + xthick + HEADER_PADDING;
	inner_y = y + ythick + HEADER_PADDING;

	/* Arrow space */

	switch (arrow) {
	case E_TABLE_COL_ARROW_NONE:
		break;

	case E_TABLE_COL_ARROW_UP:
	case E_TABLE_COL_ARROW_DOWN:
		arrow_width = MIN (MIN_ARROW_SIZE, inner_width);
		arrow_height = MIN (MIN_ARROW_SIZE, inner_height);

		if (ecol->icon_name == NULL)
			inner_width -= arrow_width + HEADER_PADDING;
		break;
	default:
		cairo_restore (cr);
		g_return_if_reached ();
	}

	if (inner_width < 1) {
		cairo_restore (cr);
		return; /* nothing else fits */
	}

	layout = build_header_layout (widget, ecol->text);
	pango_layout_set_ellipsize (layout, PANGO_ELLIPSIZE_END);

	/* Pixbuf or label */
	if (ecol->icon_name != NULL) {
		gint pwidth, pheight;
		gint clip_height;
		gint xpos;

		g_return_if_fail (ecol->pixbuf != NULL);

		pwidth = gdk_pixbuf_get_width (ecol->pixbuf);
		pheight = gdk_pixbuf_get_height (ecol->pixbuf);

		clip_height = MIN (pheight, inner_height);

		xpos = inner_x;

		if (inner_width - pwidth > 11) {
			gint ypos;

			pango_layout_get_pixel_size (layout, &width, NULL);

			if (width < inner_width - (pwidth + 1)) {
				xpos = inner_x + (inner_width - width - (pwidth + 1)) / 2;
			}

			ypos = inner_y;

			pango_layout_set_width (
				layout, (inner_width - (xpos - inner_x)) *
				PANGO_SCALE);

			cairo_move_to (cr, xpos + pwidth + 1, ypos);
			pango_cairo_show_layout (cr, layout);
		}

		gdk_cairo_set_source_pixbuf (cr, ecol->pixbuf,
					     xpos, inner_y + (inner_height - clip_height) / 2);
		cairo_paint (cr);
	} else {
		pango_layout_set_width (layout, inner_width * PANGO_SCALE);

		cairo_move_to (cr, inner_x, inner_y);
		pango_cairo_show_layout (cr, layout);
	}

	switch (arrow) {
	case E_TABLE_COL_ARROW_NONE:
		break;

	case E_TABLE_COL_ARROW_UP:
	case E_TABLE_COL_ARROW_DOWN: {
		if (ecol->icon_name == NULL)
			inner_width += arrow_width + HEADER_PADDING;

		gtk_paint_arrow (style, cr, state,
				 GTK_SHADOW_NONE, widget, "header",
				 (arrow == E_TABLE_COL_ARROW_UP) ? GTK_ARROW_UP : GTK_ARROW_DOWN,
				 (ecol->icon_name == NULL),
				 inner_x + inner_width - arrow_width,
				 inner_y + (inner_height - arrow_height) / 2,
				 arrow_width, arrow_height);
		break;
	}

	default:
		cairo_restore (cr);
		g_return_if_reached ();
	}

	g_object_unref (layout);
	cairo_restore (cr);
}