path: root/widgets/table/e-table-header-utils.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* 
 * e-table-header-utils.h
 * Copyright 2000, 2001, Ximian, Inc.
 *
 * Authors:
 *   Chris Lahey <clahey@ximian.com>
 *          Miguel de Icaza <miguel@ximian.com>
 *          Federico Mena-Quintero <federico@ximian.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License, version 2, as published by the Free Software Foundation.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

#include <config.h>

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

#include <gtk/gtk.h>

#include "misc/e-unicode.h"

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

static PangoLayout*
build_header_layout (GtkWidget *widget, const char *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.
 **/
double
e_table_header_compute_height (ETableCol *ecol, GtkWidget *widget)
{
    int ythick;
    int 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->is_pixbuf) {
        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;
}

double
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.
 */
static GdkPixmap *
make_composite_pixmap (GdkDrawable *drawable, GdkGC *gc,
               GdkPixbuf *pixbuf, GdkColor *bg, int width, int height,
               int dither_xofs, int dither_yofs)
{
    int pwidth, pheight;
    GdkPixmap *pixmap;
    GdkPixbuf *tmp;
    int 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 {
        int 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;
            int yfactor;

            p = pixels + y * rowstride;

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

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

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

                p[3] = ((int) 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;
}

/* Default width of the elision arrow in pixels */
#define ARROW_WIDTH 4

/**
 * e_table_draw_elided_string:
 * @drawable: Destination drawable.
 * @font: Font for the text.
 * @gc: GC to use for drawing.
 * @x: X insertion point for the string.
 * @y: Y insertion point for the string's baseline.
 * @layout: the PangoLayout to draw.
 * @str: the string we're drawing, passed in so we can change the layout if it needs eliding.
 * @max_width: Maximum width in which the string must fit.
 * @center: Whether to center the string in the available area if it does fit.
 * 
 * Draws a string, possibly trimming it so that it fits inside the specified
 * maximum width.  If it does not fit, an elision indicator is drawn after the
 * last character that does fit.
 **/
static void
e_table_draw_elided_string (GdkDrawable *drawable, GdkGC *gc, GtkWidget *widget, 
                int x, int y, PangoLayout *layout, char *str,
                int max_width, gboolean center)
{
    int width;
    int height;
    int index;
    GSList *lines;
    PangoLayoutLine *line;

    g_return_if_fail (drawable != NULL);
    g_return_if_fail (gc != NULL);
    g_return_if_fail (layout != NULL);
    g_return_if_fail (max_width >= 0);

    pango_layout_get_pixel_size (layout, &width, &height);

    gdk_gc_set_clip_rectangle (gc, NULL);

    if (width <= max_width) {
        int xpos;

        if (center)
            xpos = x + (max_width - width) / 2;
        else
            xpos = x;

        gdk_draw_layout (drawable, gc,
                 xpos, y,
                 layout);
    } else {
        int arrow_width;
        int i;

        if (max_width < ARROW_WIDTH + 1)
            arrow_width = max_width - 1;
        else
            arrow_width = ARROW_WIDTH;


        lines = pango_layout_get_lines (layout);
        line = lines->data;

        if (!pango_layout_line_x_to_index (line,
                           (max_width - arrow_width) * PANGO_SCALE,
                           &index,
                           NULL)) {
            g_warning ("pango_layout_line_x_to_index returned false");
            return;
        }

        pango_layout_set_text (layout, str, index);

        gdk_draw_layout (drawable, gc, x, y, layout);

        for (i = 0; i < arrow_width; i++) {
            gdk_draw_line (drawable, gc,
                       x + max_width - i,
                       y + height / 2 - i,
                       x + max_width - i,
                       y + height / 2 + i + 1);
        }
    }
}

/**
 * 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 (GdkDrawable *drawable, ETableCol *ecol,
                GtkStyle *style, GtkStateType state,
                GtkWidget *widget,
                int x, int y, int width, int height,
                int button_width, int button_height,
                ETableColArrow arrow)
{
    int xthick, ythick;
    int inner_x, inner_y;
    int inner_width, inner_height;
    GdkGC *gc;
    PangoLayout *layout;
    static gpointer g_label = NULL;

    g_return_if_fail (drawable != 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(button)->child;
        g_object_add_weak_pointer (G_OBJECT (g_label), &g_label);
        gtk_widget_ensure_style (g_label);
    }

    gc = GTK_WIDGET (g_label)->style->fg_gc[state];

    gdk_gc_set_clip_rectangle (gc, NULL);

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

    /* Button bevel */

    gtk_paint_box (style, drawable, state, GTK_SHADOW_OUT,
               NULL, 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)
        return; /* nothing fits */

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

    /* Arrow */

    switch (arrow) {
    case E_TABLE_COL_ARROW_NONE:
        break;

    case E_TABLE_COL_ARROW_UP:
    case E_TABLE_COL_ARROW_DOWN: {
        int arrow_width, arrow_height;

        arrow_width = MIN (MIN_ARROW_SIZE, inner_width);
        arrow_height = MIN (MIN_ARROW_SIZE, inner_height);

        gtk_paint_arrow (style, drawable, state,
                 GTK_SHADOW_NONE, NULL, widget, "header",
                 (arrow == E_TABLE_COL_ARROW_UP) ? GTK_ARROW_UP : GTK_ARROW_DOWN,
                 TRUE,
                 inner_x + inner_width - arrow_width,
                 inner_y + (inner_height - arrow_height) / 2,
                 arrow_width, arrow_height);

        inner_width -= arrow_width + HEADER_PADDING;
        break;
    }

    default:
        g_return_if_reached();
    }

    if (inner_width < 1)
        return; /* nothing else fits */

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

    /* Pixbuf or label */
    if (ecol->is_pixbuf) {
        int pwidth, pheight;
        int clip_width, clip_height;
        int xpos;
        GdkPixmap *pixmap;

        g_return_if_fail (ecol->pixbuf != NULL);

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

        clip_width = MIN (pwidth, inner_width);
        clip_height = MIN (pheight, inner_height);

        xpos = inner_x;

        if (inner_width - pwidth > 11) {
            int 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;

            e_table_draw_elided_string (drawable, gc, widget,
                            xpos + pwidth + 1, ypos,
                            layout, ecol->text, inner_width - (xpos - inner_x), FALSE);
        }

        pixmap = make_composite_pixmap (drawable, gc,
                        ecol->pixbuf, &style->bg[state],
                        clip_width, clip_height,
                        xpos,
                        inner_y + (inner_height - clip_height) / 2);

        gdk_gc_set_clip_rectangle (gc, NULL);

        if (pixmap) {
            gdk_draw_drawable (drawable, gc, pixmap,
                     0, 0,
                     xpos,
                     inner_y + (inner_height - clip_height) / 2,
                     clip_width, clip_height);
            g_object_unref (pixmap);
        }
    } else {
        e_table_draw_elided_string (drawable, gc, widget, 
                        inner_x, inner_y,
                        layout, ecol->text, inner_width, TRUE);
    }

    g_object_unref (layout);
}