/*  onebutton.c

    Subject: Gtk module to remap mouse buttons
    Date: Tue, 17 Jul 2001 16:13:00 +0800 (WST)
    From: James Henstridge <james@daa.com.au>
    To: <jwz@jwz.org>

    Since I had a bit of spare time, I wrote the small module to perform
    button remapping for GTK programs (as I suggested on #gnome).

    It installs an emission hook that will be called everytime an event is
    about to be handled by a widget.  It checks to see if it is a button
    event, in which case it sets the button number to 1.

    To compile, run:
      gcc -fPIC `gtk-config --cflags` -c onebutton.c
      gcc -shared onebutton.o -o onebutton.so

    Then set the GTK_MODULES environment variable:
      export GTK_MODULES=/directory/onebutton.so

    Now when you start gtk+ programs, they will load onebutton.so, which will
    install the emission hook.  Should be pretty easy to modify if you only
    want to remap one or two buttons.

    James.
 */

#include <stdlib.h>
#include <glib.h>
#include <gmodule.h>
#include <gtk/gtk.h>

static guint
munge_state (guint type, guint state)
{
# define BMASKS (GDK_BUTTON2_MASK | GDK_BUTTON3_MASK | \
                 GDK_BUTTON4_MASK | GDK_BUTTON5_MASK)
  if (state & BMASKS)
    {
      state &= (~ BMASKS);
      state |= GDK_BUTTON1_MASK;
    }
# undef BMASKS

  return state;
}


/* If it is a button press event, modify the event to look like button1
   was used.  This makes it impossible to right or middle click.
 */
static gboolean
munge_button_events (GtkObject *object, guint signal_id, guint n_params,
                     GtkArg *params, gpointer data)
{
  GdkEvent *event = GTK_VALUE_POINTER(params[0]);

  switch (event->type) {
    case GDK_BUTTON_PRESS:
    case GDK_2BUTTON_PRESS:
    case GDK_3BUTTON_PRESS:
    case GDK_BUTTON_RELEASE:
      event->button.button = 1;
      event->button.state = munge_state (event->type, event->button.state);
      break;

    case GDK_KEY_PRESS:
    case GDK_KEY_RELEASE:
      event->key.state = munge_state (event->type, event->key.state);
      break;

    case GDK_MOTION_NOTIFY:
      event->motion.state = munge_state (event->type, event->motion.state);
      break;

    case GDK_ENTER_NOTIFY:
    case GDK_LEAVE_NOTIFY:
      event->crossing.state = munge_state (event->type, event->crossing.state);
      break;
    }

  return TRUE;
}


/* the init function for this gtk module */

G_MODULE_EXPORT void gtk_module_init (gint *argc, gchar ***argv);

void
gtk_module_init (gint *argc, gchar ***argv)
{
  guint signal_id = gtk_signal_lookup ("event", GTK_TYPE_WIDGET);
  gtk_signal_add_emission_hook (signal_id, munge_button_events, NULL);
}

#if 0


/* hack hack */

#include <gdk/gdkprivate.h>

#include <stdio.h>

GdkWindow*
gdk_window_get_pointer (GdkWindow       *window,
                        gint            *x,
                        gint            *y,
                        GdkModifierType *mask)
{
  GdkWindowPrivate *private;
  GdkWindow *return_val;
  Window root;
  Window child;
  int rootx, rooty;
  int winx = 0;
  int winy = 0;
  unsigned int xmask = 0;
  
  if (!window)
    window = (GdkWindow*) &gdk_root_parent;
  
  private = (GdkWindowPrivate*) window;
  
  fprintf (stderr, "#### foo\n");

  return_val = NULL;
  if (!private->destroyed &&
      XQueryPointer (private->xdisplay, private->xwindow, &root, &child,
                     &rootx, &rooty, &winx, &winy, &xmask))
    {
      if (child)
        return_val = gdk_window_lookup (child);
    }
  
  if (x)
    *x = winx;
  if (y)
    *y = winy;
  if (mask)
    *mask = xmask;

  return return_val;
}

#endif /* 0 */