/* This file is part of herzi's playground
 *
 * AUTHORS
 *     Sven Herzberg  <herzi@gnome-de.org>
 *
 * Copyright (C) 2006  Sven Herzberg <herzi@gnome-de.org>
 *
 * 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 2.1 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser 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
 */

#include "gobject-helpers.h"

/* interface definition */
typedef struct _Printable Printable;
typedef struct _PrintableIface {
	GTypeInterface iface;
	void (*print) (Printable* self);
} PrintableIface;
#define PRINTABLE(i) G_TYPE_CHECK_INSTANCE_CAST((i), printable_get_type(), Printable)
G_DEFINE_IFACE(Printable, printable, G_TYPE_INTERFACE);
static void
printable_print(Printable* self) {
	g_return_if_fail(G_TYPE_INSTANCE_GET_INTERFACE(self, printable_get_type(), PrintableIface)->print);

	G_TYPE_INSTANCE_GET_INTERFACE(self, printable_get_type(), PrintableIface)->print(self);
}

/* parent class */
typedef GObject      Foo;
typedef GObjectClass FooClass;
static void foo_print(Printable* printable) {
	g_print("Foo instance: %p\n", printable);
}
static void foo_impl_printable(PrintableIface* iface) {
	iface->print = foo_print;
}
G_DEFINE_TYPE_WITH_CODE(Foo, foo, G_TYPE_OBJECT,
			G_IMPLEMENT_INTERFACE(printable_get_type(), foo_impl_printable));
static void foo_init(Foo* self) {};
static void foo_class_init(FooClass* self_class) {}

/* first child class (no chaining up) */
typedef Foo      FooBar;
typedef FooClass FooBarClass;
static void foo_bar_print(Printable* printable) {
	g_print("FooBar instance: %p (is also Foo, but we don't want to tell :P)\n", printable);
}
static void foo_bar_impl_printable(PrintableIface* iface) {
	iface->print = foo_bar_print;
}
G_DEFINE_TYPE_WITH_CODE(FooBar, foo_bar, foo_get_type(),
			G_IMPLEMENT_INTERFACE(printable_get_type(), foo_bar_impl_printable));
static void foo_bar_init(FooBar* self) {}
static void foo_bar_class_init(FooBarClass* self_class) {}

/* second child class (with evil up-chaining) */
typedef Foo      Foobar;
typedef FooClass FoobarClass;
static void foobar_print(Printable* printable);
static void foobar_impl_printable(PrintableIface* iface) {
	iface->print = foobar_print;
}
G_DEFINE_TYPE_WITH_CODE(Foobar, foobar, foo_get_type(),
			G_IMPLEMENT_INTERFACE(printable_get_type(), foobar_impl_printable));
static void foobar_print(Printable* printable) {
	if(((PrintableIface*)g_type_interface_peek(foobar_parent_class, printable_get_type()))->print) {
		((PrintableIface*)g_type_interface_peek(foobar_parent_class, printable_get_type()))->print(printable);
	}
	g_print("Foobar instance: %p\n", printable);
}
static void foobar_init(Foobar* self) {}
static void foobar_class_init(FoobarClass* self_class) {}

int
main(int argc, char** argv) {
	gpointer test;
	g_type_init();

	test = g_object_new(foo_get_type(), NULL);
	printable_print(PRINTABLE(test));
	g_object_unref(test);

	test = g_object_new(foo_bar_get_type(), NULL);
	printable_print(PRINTABLE(test));
	g_object_unref(test);

	test = g_object_new(foobar_get_type(), NULL);
	printable_print(PRINTABLE(test));
	g_object_unref(test);
	return 0;
}