/* Build with: gcc `pkg-config --cflags --libs gtk+-2.0` typing.c */

/*
 * The point of this program is to illustrate
 *   https://bugs.freedesktop.org/show_bug.cgi?id=1738.
 *
 * It's a GTK+ app that has a window with two text fields labeled
 * "slow" and "normal".  The normal one is a normal text field (what
 * else?).  The slow one sleeps for 0,5s after each key press.
 *
 * If you press and hold "u" (for example), the slow box will keep
 * printing "u"s for long after you release the button.  Bad.
 */

#include <unistd.h>
#include <gtk/gtk.h>
#include <gdk/gdk.h>

#define DELAY_MS 500

/*
 * Terminate the main loop.
 */
static void
on_destroy (GtkWidget * widget, gpointer data) {
  (void)widget;
  (void)data;
  gtk_main_quit ();
}

/*
 * Slow down the slow text box.
 */
void delay(GtkEditable *editable, gpointer user_data) {
  (void)editable;
  (void)user_data;
  GdkWindow *updateMe;
  GdkRegion *bounds;
  
  usleep(DELAY_MS * 1000);
  
  // Repaint the widget
  updateMe = gtk_widget_get_parent_window(GTK_WIDGET(editable));
  bounds = gdk_drawable_get_visible_region(updateMe);
  gdk_window_invalidate_region(updateMe, bounds, TRUE);
  gdk_region_destroy(bounds);
  gdk_window_process_updates(updateMe, TRUE);
}

int
main (int argc, char *argv[])
{
  GtkWidget *window;
  GtkWidget *table;
  GtkWidget *slowEntry;
  
  gtk_init (&argc, &argv);

  /* create the main, top level, window */
  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);

  /* give it the title */
  gtk_window_set_title (GTK_WINDOW (window), "Typing test");

  /* open it a bit wider so that both the label and title show up */
  gtk_window_set_default_size (GTK_WINDOW (window), 200, 50);

  /* Connect the destroy event of the window with our on_destroy function
   * When the window is about to be destroyed we get a notificaiton and
   * stop the main GTK loop
   */
  g_signal_connect (G_OBJECT (window), "destroy",
		    G_CALLBACK (on_destroy), NULL);

  /* Create the table used for layout */
  table = gtk_table_new(2, 2, FALSE);
  gtk_table_attach_defaults(GTK_TABLE(table),
			    GTK_WIDGET(gtk_label_new("Slow:")), 0, 1, 0, 1);
  slowEntry = gtk_entry_new();
  g_signal_connect(G_OBJECT(slowEntry), "changed",
		   G_CALLBACK(delay), NULL);
  gtk_table_attach_defaults(GTK_TABLE(table),
			    slowEntry, 1, 2, 0, 1);
  gtk_table_attach_defaults(GTK_TABLE(table),
			    GTK_WIDGET(gtk_label_new("Normal:")), 0, 1, 1, 2);
  gtk_table_attach_defaults(GTK_TABLE(table),
			    GTK_WIDGET(gtk_entry_new()), 1, 2, 1, 2);
  gtk_container_add (GTK_CONTAINER (window), GTK_WIDGET(table));
  
  /* make sure that everything, window and label, are visible */
  gtk_widget_show_all (window);

  /* start the main loop */
  gtk_main ();

  return 0;
}