#include <gtk/gtk.h>
#include <glib-object.h>

#define GTK_PARAM_WRITABLE G_PARAM_WRITABLE|G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB
#define P_(x) (x)

typedef struct
{
  GObject parent_instance;
} Custom;

typedef struct
{
  GObjectClass parent_class;
} CustomClass;

typedef GObject * (*CustomCreationFunction) (const gchar *name,
					     const gchar *string1,
					     const gchar *string2,
					     int int1,
					     int int2);

static GObject * custom_constructor  (GType                  type,
				      guint                  n_construct_properties,
				      GObjectConstructParam *construct_properties);
static void      custom_set_property (GObject               *object,
				      guint                  prop_id,
				      const GValue          *value,
				      GParamSpec            *pspec);

#define TYPE_CUSTOM                 (custom_get_type ())
#define CUSTOM(obj)                 (G_TYPE_CHECK_INSTANCE_CAST ((obj), TYPE_CUSTOM, Custom))

G_DEFINE_TYPE (Custom, custom, G_TYPE_OBJECT)

enum {
  PROP_0,
  PROP_CREATION_FUNCTION,
  PROP_STRING1,
  PROP_STRING2,
  PROP_INT1,
  PROP_INT2,
  PROP_LAST_MODIFICATION_TIME,
  PROP_VISIBLE
};

static void
custom_class_init (CustomClass *klass)
{
  GObjectClass *gobject_class;

  gobject_class = G_OBJECT_CLASS (klass);

  gobject_class->constructor = custom_constructor;
  gobject_class->set_property = custom_set_property;

  g_object_class_install_property (gobject_class,
                                   PROP_CREATION_FUNCTION,
                                   g_param_spec_string ("creation-function",
                                                        P_("Creation function"),
                                                        P_("This function will be called to create the object"),
                                                        NULL,
                                                        GTK_PARAM_WRITABLE|G_PARAM_CONSTRUCT_ONLY));

  g_object_class_install_property (gobject_class,
                                   PROP_STRING1,
                                   g_param_spec_string ("string1",
                                                        P_("String1"),
                                                        NULL,
                                                        NULL,
                                                        GTK_PARAM_WRITABLE|G_PARAM_CONSTRUCT_ONLY));

  g_object_class_install_property (gobject_class,
                                   PROP_STRING1,
                                   g_param_spec_string ("string2",
                                                        P_("String2"),
                                                        NULL,
                                                        NULL,
                                                        GTK_PARAM_WRITABLE|G_PARAM_CONSTRUCT_ONLY));

  g_object_class_install_property (gobject_class,
                                   PROP_INT1,
                                   g_param_spec_int ("int1",
						     P_("Int1"),
                                                     NULL,
						     -G_MAXINT,
						     G_MAXINT,
						     0,
						     GTK_PARAM_WRITABLE|G_PARAM_CONSTRUCT_ONLY));

  g_object_class_install_property (gobject_class,
                                   PROP_INT2,
                                   g_param_spec_int ("int2",
						     P_("Int2"),
                                                     NULL,
						      -G_MAXINT,
						     G_MAXINT,
						     0,
						     GTK_PARAM_WRITABLE|G_PARAM_CONSTRUCT_ONLY));

  g_object_class_install_property (gobject_class,
                                   PROP_LAST_MODIFICATION_TIME,
                                   g_param_spec_string ("last-modification-time",
							P_("Last modification time"),
							NULL,
							NULL,
							GTK_PARAM_WRITABLE|G_PARAM_CONSTRUCT_ONLY));

  g_object_class_install_property (gobject_class,
                                   PROP_VISIBLE,
                                   g_param_spec_boolean ("visible",
							 P_("Visible"),
							 NULL,
							 FALSE,
							 GTK_PARAM_WRITABLE|G_PARAM_CONSTRUCT_ONLY));
}

static void
custom_init (Custom *custom)
{
}

static void
custom_set_property (GObject      *object,
		     guint         prop_id,
		     const GValue *value,
		     GParamSpec   *pspec)
{
  /* dummy implementation, it's never called, GObject just checks if its set */
}

static GObject *
custom_constructor (GType                  type,
		    guint                  n_construct_properties,
		    GObjectConstructParam *construct_properties)
{
  GModule *module = NULL;
  CustomCreationFunction func;
  GObject *obj = NULL;
  const gchar *creation_function;
  const gchar *string1 = NULL;
  const gchar *string2 = NULL;
  int int1 = 0;
  int int2 = 0;
  int i;
  gboolean visible = FALSE;
  
  for (i = 0; i < n_construct_properties; i++)
    {
      GParamSpec *param = construct_properties[i].pspec;
      GValue * value = construct_properties[i].value;

      switch (param->param_id)
	{
	case PROP_CREATION_FUNCTION:
	  creation_function = g_value_get_string (value);
	  break;
	case PROP_STRING1:
	  string1 = g_value_get_string (value);
	  break;
	case PROP_STRING2:
	  string2 = g_value_get_string (value);
	  break;
	case PROP_INT1:
	  int1 = g_value_get_int (value);
	  break;
	case PROP_INT2:
	  int2 = g_value_get_int (value);
	  break;
	case PROP_LAST_MODIFICATION_TIME:
	  break;
	case PROP_VISIBLE:
	  visible = g_value_get_boolean (value);
	  break;
	default:
	  g_warning ("%s: invalid property id %u for \"%s\" of type `%s' in `%s'", 
		     G_STRLOC,						
		     param->param_id,		
		     param->name,		       
		     g_type_name (G_PARAM_SPEC_TYPE (param)),	
		     g_type_name (type));	
	  break;
	}
      
    }

  module = g_module_open (NULL, 0);

  if (g_module_symbol (module, creation_function, (gpointer)&func))
    obj = func (creation_function, string1, string2, int1, int2);

  if (!obj)
    g_error ("Custom creation function `%s' did not return a GObject\n",
	     creation_function);
  else if (GTK_IS_WIDGET (obj) && visible)
    gtk_widget_show (GTK_WIDGET (obj));

  g_module_close (module);
  
  return obj;
}

#if 0
/* test */
GObject* test_foo (const gchar *name,
		   const gchar *string1,
		   const gchar *string2,
		   int int1,
		   int int2)
{
  return G_OBJECT (gtk_window_new (GTK_WINDOW_TOPLEVEL));
}

int main(int argc, char **argv)
{
  GObject *obj;
  
  gtk_init (&argc, &argv);

  obj = g_object_new (TYPE_CUSTOM,
		      "creation-function", "test_foo",
		      "string1", "ettan",
		      "string2", "tvåan",
		      "int1", 10,
		      "int2", 42,
		      "visible", TRUE,
		      NULL);
  g_return_val_if_fail(obj != NULL, 1);
  g_print ("%s\n", g_type_name (G_OBJECT_TYPE (obj)));

  gtk_widget_destroy (GTK_WIDGET (obj));
  
  return 0;
}
#endif