/** @file gobj-example.c
 *  @brief Example usage of QOF to query a set of GObjects.
 *  @author Copyright (c) 2004 Linas Vepstas <linas@linas.org>
 *
 * This example program shows how to use QOF to query over a set
 * of GObjects.  In this example, the query is performed over
 * three ?GtkButtons, each having a different label.  The result
 * of the search is the one ?GtkButton with the desired label.
 *
 * The use of ?GtkButton in this example is artificial.  GLib
 * GObjects do not have to be GUI objects, and can be created 
 * for any use desired.  I didn't want to turn this into an 
 * example of how to create a GObject, and so used a pre-existing
 * GObject, the ?GtkButton.
 */

#include <qof/qof.h>
#include <gtk/gtk.h>

int
main(int argc, char *argv[])
{
    g_type_init ();
    gtk_init (&argc, &argv);
    qof_gobject_init ();

    /* Register a new searchable type */
    ?GtkWidget *w = gtk_button_new_with_label ("Howdy Doody");
    ?GtkButtonClass * wc = GTK_BUTTON_GET_CLASS(w);
    GObjectClass *goc = G_OBJECT_CLASS(wc);

    qof_gobject_register ("MyGtkButton", goc);

    /* Add a number of instances to the collection */
    ?QofBook *book =  qof_book_new();
    qof_gobject_register_instance (book, "MyGtkButton", G_OBJECT(w));

    w = gtk_button_new_with_label ("dorf");
    qof_gobject_register_instance (book, "MyGtkButton", G_OBJECT(w));

    w = gtk_button_new_with_label ("zinger");
    qof_gobject_register_instance (book, "MyGtkButton", G_OBJECT(w));

    printf ("\nCreated three objects and registered them\n\n");

    /* Create a new query, run that query */
    ?QofSqlQuery *q;
    q =  qof_sql_query_new ();

    /* Set the book to be searched */
    qof_sql_query_set_book(q, book);

    char * qstr = "SELECT * FROM ?MyGtkButton WHERE (label = 'dorf')";
    printf ("Going to perform the query %s\n", qstr); 

    GList *results = qof_sql_query_run (q, qstr);
    printf ("\nQuery returned %d results\n", g_list_length (results));

    GList *n;
    for (n=results; n; n=n->next)
    {
        ?GtkWidget *qw = n->data;
        if (GTK_IS_BUTTON(qw))
        {
            ?GtkButton *bw = GTK_BUTTON (qw);
            printf ("Found a button whose label is %s\n", gtk_button_get_label(bw));
        }
    }

    qof_gobject_shutdown ();
    return 0;
}

/* =================== END OF FILE ===================== */