/* Hacked "hello world" GTK program to flash a big message.
   
   Ben Collins-Sussman <sussman@red-bean.com>

   To compile:

     gcc -Wall -g gpopup.c -o gpopup `gtk-config --cflags` \
           `gtk-config --libs`

 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <gtk/gtk.h>

/* This is a callback function. The data arguments are ignored
 * in this example. More on callbacks below. */
void hello( GtkWidget *widget,
            gpointer   data )
{
  /* g_print ("Hello World\n"); */
}

gint delete_event( GtkWidget *widget,
                   GdkEvent  *event,
                   gpointer   data )
{
  /* If you return FALSE in the "delete_event" signal handler,
   * GTK will emit the "destroy" signal. Returning TRUE means
   * you don't want the window to be destroyed.
   * This is useful for popping up 'are you sure you want to quit?'
   * type dialogs. */
  
  g_print ("delete event occurred\n");
  
  /* Change TRUE to FALSE and the main window will be destroyed with
   * a "delete_event". */
  
  return(TRUE);
}

/* Another callback */
void destroy( GtkWidget *widget,
              gpointer   data )
{
  gtk_main_quit();
}

int main( int   argc,
          char *argv[] )
{
  /* GtkWidget is the storage type for widgets */
  GtkWidget *window;
  GtkWidget *button;
  
  /* This is called in all GTK applications. Arguments are parsed
   * from the command line and are returned to the application. */
  gtk_init(&argc, &argv);
  
  /* create a new window */
  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  
  /* When the window is given the "delete_event" signal (this is given
   * by the window manager, usually by the "close" option, or on the
   * titlebar), we ask it to call the delete_event () function
   * as defined above. The data passed to the callback
   * function is NULL and is ignored in the callback function. */
  gtk_signal_connect (GTK_OBJECT (window), "delete_event",
                      GTK_SIGNAL_FUNC (delete_event), NULL);
  
  /* Here we connect the "destroy" event to a signal handler.  
   * This event occurs when we call gtk_widget_destroy() on the window,
   * or if we return FALSE in the "delete_event" callback. */
  gtk_signal_connect (GTK_OBJECT (window), "destroy",
                      GTK_SIGNAL_FUNC (destroy), NULL);
  
  /* Sets the border width of the window. */
  gtk_container_set_border_width (GTK_CONTAINER (window), 10);
  
  /* Creates a new button with label consisting of all args. */
  if (argc >= 2)
  {
    int total_len = 0;
    int i;
    char *msg;

    for (i = 1; argv[i]; i++)
    {
      /* Add 1 for the " " separator(s). */
      total_len += (strlen (argv[i]) + 1);
    }

    msg = malloc (total_len + 1);
    strcpy (msg, "");

    for (i = 1; argv[i]; i++)
    {
      strcat (msg, argv[i]);
      strcat (msg, " "); /* assume a space between each argument */
    }
    
    button = gtk_button_new_with_label (msg);
    free (msg);
  }
  else 
    {
      fprintf(stderr, "\nUsage:  gpopup <string>\n\n");
      exit (1);
    }

  /* Cause any keyboard event to window to call the destroy() callback */
  gtk_signal_connect (GTK_OBJECT (window), "key_press_event",
                      GTK_SIGNAL_FUNC (gtk_widget_destroy), 
                      GTK_OBJECT (window));

  /* When the button receives the "clicked" signal, it will call the
   * function hello() passing it NULL as its argument.  The hello()
   * function is defined above. */
  gtk_signal_connect (GTK_OBJECT (button), "clicked",
                      GTK_SIGNAL_FUNC (hello), NULL);
  
  /* This will cause the window to be destroyed by calling
   * gtk_widget_destroy(window) when "clicked".  Again, the destroy
   * signal could come from here, or the window manager. */
  gtk_signal_connect_object (GTK_OBJECT (button), "clicked",
                             GTK_SIGNAL_FUNC (gtk_widget_destroy),
                             GTK_OBJECT (window));
  
  /* This packs the button into the window (a gtk container). */
  gtk_container_add (GTK_CONTAINER (window), button);
  
  gtk_widget_set_usize (button, 800, 600);

  /* The final step is to display this newly created widget. */
  gtk_widget_show (button);
  
  /* and the window */
  gtk_widget_show (window);
  
  /* All GTK applications must have a gtk_main(). Control ends here
   * and waits for an event to occur (like a key press or
   * mouse event). */
  gtk_main ();
  
  return(0);
}
/* example-end */