/* gEDA - GPL Electronic Design Automation
 * gschem - gEDA Schematic Capture
 * Copyright (C) 1998-2010 gEDA Contributors (see ChangeLog for details)
 *
 * Code based on GTK 2.14.5 gtk/gtkaccellabel.c (LGPL)
 *
 * GTK - The GIMP Toolkit
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * GschemAccelLabel: GtkLabel with accelerator monitoring facilities.
 * Copyright (C) 1998 Tim Janik
 *
 * Modified by the GTK+ Team and others 1997-2001.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
 *
 *  Adapted for gEDA by Peter Clifton <pcjc2@cam.ac.uk>
 *
 *  THIS FILE IS LGPL LICENSED, pcb-rnd AS A WHOLE IS GPL LICENSED
 *
 * This library 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) any later version.
 *
 * 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
 * Lesser 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
 */

/* This file has been copied from gschem sources. It seems gtk's bondage
and discipline menu item simply cna not handle arbitrary accel label text
and the default accel label widget works only if gtk takes over handling
accel key input. In pbc-rnd there's a central input key handling and support
for multi-key sequences. gschem had the same problem because of multi-key,
and came up with this solution to rewrite the accel label object.

Modifications:
	- indentation
	- #includes
	- helper call that creates a menu item with label and accel label
*/

#include <glib.h>
#include <gtk/gtk.h>
#include "gschem_accel_label.h"

#define P_(x) (x)

enum {
	PROP_0,
	PROP_ACCEL_CLOSURE,
	PROP_ACCEL_WIDGET,
	PROP_ACCEL_STRING,
};

G_DEFINE_TYPE(GschemAccelLabel, gschem_accel_label, GTK_TYPE_ACCEL_LABEL)


gboolean gschem_accel_label_refetch(GschemAccelLabel * accel_label)
{
	gboolean enable_accels;

	g_return_val_if_fail(GSCHEM_IS_ACCEL_LABEL(accel_label), FALSE);

	g_object_get(gtk_widget_get_settings(GTK_WIDGET(accel_label)), "gtk-enable-accels", &enable_accels, NULL);

	if (!enable_accels || accel_label->accel_string == NULL) {
		if (accel_label->accel_string != NULL)
			g_free(accel_label->accel_string);

		accel_label->accel_string = g_strdup("");
	}

	gtk_widget_queue_resize(GTK_WIDGET(accel_label));

	return FALSE;
}


static const gchar *gschem_accel_label_get_string(GschemAccelLabel * accel_label)
{
	if (!accel_label->accel_string)
		gschem_accel_label_refetch(accel_label);

	return accel_label->accel_string;
}


static void gschem_accel_label_set_property(GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec)
{
	GschemAccelLabel *accel_label;

	accel_label = GSCHEM_ACCEL_LABEL(object);

	switch (prop_id) {
		/* Dummy properties from GtkAccelLabel */
	case PROP_ACCEL_CLOSURE:
	case PROP_ACCEL_WIDGET:
		break;

	case PROP_ACCEL_STRING:
		gschem_accel_label_set_accel_string(accel_label, g_value_get_string(value));
		break;
	default:
		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
		break;
	}
}

static void gschem_accel_label_get_property(GObject * object, guint prop_id, GValue * value, GParamSpec * pspec)
{
	GschemAccelLabel *accel_label;

	accel_label = GSCHEM_ACCEL_LABEL(object);

	switch (prop_id) {
		/* Dummy property from GtkAccelLabel */
	case PROP_ACCEL_CLOSURE:
		g_value_set_boxed(value, NULL);
		break;

		/* Dummy property from GtkAccelLabel */
	case PROP_ACCEL_WIDGET:
		g_value_set_object(value, NULL);
		break;

	case PROP_ACCEL_STRING:
		g_value_set_string(value, accel_label->accel_string);
		break;

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

static void gschem_accel_label_init(GschemAccelLabel * accel_label)
{
	accel_label->accel_padding = 3;
	accel_label->accel_string = NULL;
}

static void gschem_accel_label_finalize(GObject * object)
{
	GschemAccelLabel *accel_label = GSCHEM_ACCEL_LABEL(object);

	g_free(accel_label->accel_string);

	G_OBJECT_CLASS(gschem_accel_label_parent_class)->finalize(object);
}

guint gschem_accel_label_get_accel_width(GschemAccelLabel * accel_label)
{
	g_return_val_if_fail(GSCHEM_IS_ACCEL_LABEL(accel_label), 0);

	return (accel_label->accel_string_width + (accel_label->accel_string_width ? accel_label->accel_padding : 0));
}

static void gschem_accel_label_size_request(GtkWidget * widget, GtkRequisition * requisition)
{
	GschemAccelLabel *accel_label = GSCHEM_ACCEL_LABEL(widget);
	GtkAccelLabel *gtk_accel_label = GTK_ACCEL_LABEL(widget);
	PangoLayout *layout;
	gint width;

	GTK_WIDGET_CLASS(gschem_accel_label_parent_class)->size_request(widget, requisition);

	layout = gtk_widget_create_pango_layout(widget, gschem_accel_label_get_string(accel_label));
	pango_layout_get_pixel_size(layout, &width, NULL);
	accel_label->accel_string_width = width;
	gtk_accel_label->accel_string_width = width;	/* HACK: This field is private to GtkAccelLabel */
	g_object_unref(layout);
}

static gint get_first_baseline(PangoLayout * layout)
{
	PangoLayoutIter *iter;
	gint result;

	iter = pango_layout_get_iter(layout);
	result = pango_layout_iter_get_baseline(iter);
	pango_layout_iter_free(iter);

	return PANGO_PIXELS(result);
}

static gboolean gschem_accel_label_expose_event(GtkWidget * widget, GdkEventExpose * event)
{
	GschemAccelLabel *accel_label = GSCHEM_ACCEL_LABEL(widget);
	GtkMisc *misc = GTK_MISC(accel_label);
	GtkTextDirection direction;

	direction = gtk_widget_get_direction(widget);

	if (gtk_widget_is_drawable(GTK_WIDGET(accel_label))) {
		guint ac_width;

		ac_width = gschem_accel_label_get_accel_width(accel_label);

		if (widget->allocation.width >= widget->requisition.width + ac_width) {
			PangoLayout *label_layout;
			PangoLayout *accel_layout;
			GtkLabel *label = GTK_LABEL(widget);

			gint x;
			gint y;

			label_layout = gtk_label_get_layout(GTK_LABEL(accel_label));

			if (direction == GTK_TEXT_DIR_RTL)
				widget->allocation.x += ac_width;
			widget->allocation.width -= ac_width;
			if (gtk_label_get_ellipsize(label))
				pango_layout_set_width(label_layout, pango_layout_get_width(label_layout)
															 - ac_width * PANGO_SCALE);

			if (GTK_WIDGET_CLASS(gschem_accel_label_parent_class)->expose_event)
				GTK_WIDGET_CLASS(gschem_accel_label_parent_class)->expose_event(widget, event);
			if (direction == GTK_TEXT_DIR_RTL)
				widget->allocation.x -= ac_width;
			widget->allocation.width += ac_width;
			if (gtk_label_get_ellipsize(label))
				pango_layout_set_width(label_layout, pango_layout_get_width(label_layout)
															 + ac_width * PANGO_SCALE);

			if (direction == GTK_TEXT_DIR_RTL)
				x = widget->allocation.x + misc->xpad;
			else
				x = widget->allocation.x + widget->allocation.width - misc->xpad - ac_width;

			gtk_label_get_layout_offsets(GTK_LABEL(accel_label), NULL, &y);

			accel_layout = gtk_widget_create_pango_layout(widget, gschem_accel_label_get_string(accel_label));

			y += get_first_baseline(label_layout) - get_first_baseline(accel_layout);

			gtk_paint_layout(widget->style,
											 widget->window,
											 gtk_widget_get_state(widget), FALSE, &event->area, widget, "accellabel", x, y, accel_layout);

			g_object_unref(accel_layout);
		}
		else {
			if (GTK_WIDGET_CLASS(gschem_accel_label_parent_class)->expose_event)
				GTK_WIDGET_CLASS(gschem_accel_label_parent_class)->expose_event(widget, event);
		}
	}

	return FALSE;
}

/* Underscores in key names are better displayed as spaces
 * E.g., Page_Up should be "Page Up"
 */
static void substitute_underscores(char *str)
{
	char *p;

	for (p = str; *p; p++)
		if (*p == '_')
			*p = ' ';
}


/**
 * gschem_accel_label_set_accel_string:
 * \param accel_label a #GschemAccelLabel
 * \param accel_string the accelerator string.
 *
 * Sets the accelerator string for this accelerator label.
 **/
void gschem_accel_label_set_accel_string(GschemAccelLabel * accel_label, const gchar * accel_string)
{
	g_return_if_fail(GSCHEM_IS_ACCEL_LABEL(accel_label));

	if (accel_label->accel_string)
		g_free(accel_label->accel_string);

	if (accel_string) {
		accel_label->accel_string = g_strdup(accel_string);
		substitute_underscores(accel_label->accel_string);
	}
	else {
		accel_label->accel_string = NULL;
	}

	g_object_notify(G_OBJECT(accel_label), "accel-string");
}

static void gschem_accel_label_class_init(GschemAccelLabelClass * class)
{
	GObjectClass *gobject_class = G_OBJECT_CLASS(class);
	GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(class);

	gobject_class->finalize = gschem_accel_label_finalize;
	gobject_class->set_property = gschem_accel_label_set_property;
	gobject_class->get_property = gschem_accel_label_get_property;

	widget_class->size_request = gschem_accel_label_size_request;
	widget_class->expose_event = gschem_accel_label_expose_event;

	g_object_class_install_property(gobject_class,
																	PROP_ACCEL_CLOSURE,
																	g_param_spec_boxed("accel-closure",
																										 P_("Accelerator Closure"),
																										 P_("The closure to be monitored for accelerator changes"),
																										 G_TYPE_CLOSURE, G_PARAM_READWRITE));
	g_object_class_install_property(gobject_class,
																	PROP_ACCEL_WIDGET,
																	g_param_spec_object("accel-widget",
																											P_("Accelerator Widget"),
																											P_("The widget to be monitored for accelerator changes"),
																											GTK_TYPE_WIDGET, G_PARAM_READWRITE));
	g_object_class_install_property(gobject_class,
																	PROP_ACCEL_STRING,
																	g_param_spec_string("accel-string",
																											P_("Accelerator String"),
																											P_("The accelerator string to be displayed"), NULL, G_PARAM_READWRITE));
}

GtkWidget *gtk_menu_item_new_gschem(const char *label, const char *accel_label)
{
	GtkWidget *w = gtk_menu_item_new();
	GschemAccelLabel *al = g_object_new (GSCHEM_TYPE_ACCEL_LABEL,
		"use-underline", TRUE,
		"xalign", 0.0,
		"visible", TRUE,
		"label", label,
		"accel-string", accel_label,
		NULL);
	gtk_container_add(GTK_CONTAINER(w), GTK_WIDGET(al));
	return w;
}