/* -*- indent-tabs-mode: nil; tab-width: 4; c-basic-offset: 4; -*-

   grab.c for the Openbox window manager
   Copyright (c) 2006        Mikael Magnusson
   Copyright (c) 2003        Ben Jansens

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   See the COPYING file for a copy of the GNU General Public License.
*/

#include "grab.h"
#include "openbox.h"
#include "event.h"
#include "xerror.h"
#include "screen.h"

#include <glib.h>
#include <X11/Xlib.h>

#define GRAB_PTR_MASK (ButtonPressMask | ButtonReleaseMask | PointerMotionMask)
#define GRAB_KEY_MASK (KeyPressMask | KeyReleaseMask)

#define MASK_LIST_SIZE 8

/*! A list of all possible combinations of keyboard lock masks */
static guint mask_list[MASK_LIST_SIZE];
static guint kgrabs = 0;
static guint pgrabs = 0;
/*! The time at which the last grab was made */
static Time  grab_time = CurrentTime;

static Time ungrab_time()
{
    Time t = event_curtime;
    if (!(t == 0 || event_time_after(t, grab_time)))
        t = grab_time;
    return t;
}

gboolean grab_on_keyboard()
{
    return kgrabs > 0;
}

gboolean grab_on_pointer()
{
    return pgrabs > 0;
}

gboolean grab_keyboard(gboolean grab)
{
    gboolean ret = FALSE;

    if (grab) {
        if (kgrabs++ == 0) {
            ret = XGrabKeyboard(ob_display, RootWindow(ob_display, ob_screen),
                                FALSE, GrabModeAsync, GrabModeAsync,
                                event_curtime) == Success;
            if (!ret)
                --kgrabs;
            else
                grab_time = event_curtime;
        } else
            ret = TRUE;
    } else if (kgrabs > 0) {
        if (--kgrabs == 0) {
            XUngrabKeyboard(ob_display, ungrab_time());
        }
        ret = TRUE;
    }

    return ret;
}

gboolean grab_pointer(gboolean grab, ObCursor cur)
{
    gboolean ret = FALSE;

    if (grab) {
        if (pgrabs++ == 0) {
            ret = XGrabPointer(ob_display, screen_support_win,
                               False, GRAB_PTR_MASK, GrabModeAsync,
                               GrabModeAsync, None,
                               ob_cursor(cur), event_curtime) == Success;
            if (!ret)
                --pgrabs;
            else
                grab_time = event_curtime;
        } else
            ret = TRUE;
    } else if (pgrabs > 0) {
        if (--pgrabs == 0) {
            XUngrabPointer(ob_display, ungrab_time());
        }
        ret = TRUE;
    }
    return ret;
}

gboolean grab_pointer_window(gboolean grab, ObCursor cur, Window win)
{
    gboolean ret = FALSE;

    if (grab) {
        if (pgrabs++ == 0) {
            ret = XGrabPointer(ob_display, win, False, GRAB_PTR_MASK,
                               GrabModeAsync, GrabModeAsync, None,
                               ob_cursor(cur),
                               event_curtime) == Success;
            if (!ret)
                --pgrabs;
            else
                grab_time = event_curtime;
        } else
            ret = TRUE;
    } else if (pgrabs > 0) {
        if (--pgrabs == 0) {
            XUngrabPointer(ob_display, ungrab_time());
        }
        ret = TRUE;
    }
    return ret;
}

gint grab_server(gboolean grab)
{
    static guint sgrabs = 0;
    if (grab) {
        if (sgrabs++ == 0) {
            XGrabServer(ob_display);
            XSync(ob_display, FALSE);
        }
    } else if (sgrabs > 0) {
        if (--sgrabs == 0) {
            XUngrabServer(ob_display);
            XFlush(ob_display);
        }
    }
    return sgrabs;
}

void grab_startup(gboolean reconfig)
{
    guint i = 0;

    if (reconfig) return;

    mask_list[i++] = 0;
    mask_list[i++] = LockMask;
    mask_list[i++] = NumLockMask;
    mask_list[i++] = LockMask | NumLockMask;
    mask_list[i++] = ScrollLockMask;
    mask_list[i++] = ScrollLockMask | LockMask;
    mask_list[i++] = ScrollLockMask | NumLockMask;
    mask_list[i++] = ScrollLockMask | LockMask | NumLockMask;
    g_assert(i == MASK_LIST_SIZE);
}

void grab_shutdown(gboolean reconfig)
{
    if (reconfig) return;

    while (grab_keyboard(FALSE));
    while (grab_pointer(FALSE, OB_CURSOR_NONE));
    while (grab_pointer_window(FALSE, OB_CURSOR_NONE, None));
    while (grab_server(FALSE));
}

void grab_button_full(guint button, guint state, Window win, guint mask,
                      gint pointer_mode, ObCursor cur)
{
    guint i;

    xerror_set_ignore(TRUE); /* can get BadAccess' from these */
    xerror_occured = FALSE;
    for (i = 0; i < MASK_LIST_SIZE; ++i)
        XGrabButton(ob_display, button, state | mask_list[i], win, FALSE, mask,
                    pointer_mode, GrabModeSync, None, ob_cursor(cur));
    xerror_set_ignore(FALSE);
    if (xerror_occured)
        g_warning("failed to grab button %d modifiers %d", button, state);
}

void grab_button(guint button, guint state, Window win, guint mask)
{
    grab_button_full(button, state, win, mask, GrabModeAsync, OB_CURSOR_NONE);
}

void ungrab_button(guint button, guint state, Window win)
{
    guint i;

    for (i = 0; i < MASK_LIST_SIZE; ++i)
        XUngrabButton(ob_display, button, state | mask_list[i], win);
}

void grab_key(guint keycode, guint state, Window win, gint keyboard_mode)
{
    guint i;

    xerror_set_ignore(TRUE); /* can get BadAccess' from these */
    xerror_occured = FALSE;
    for (i = 0; i < MASK_LIST_SIZE; ++i)
        XGrabKey(ob_display, keycode, state | mask_list[i], win, FALSE,
                 GrabModeAsync, keyboard_mode);
    xerror_set_ignore(FALSE);
    if (xerror_occured)
        g_warning("failed to grab keycode %d modifiers %d", keycode, state);
}

void ungrab_all_keys(Window win)
{
    XUngrabKey(ob_display, AnyKey, AnyModifier, win);
}