/*      $NetBSD: panel_impl.h,v 1.3 2022/04/19 20:32:17 rillig Exp $ */

/*
* Copyright (c) 2015 Valery Ushakov
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef _PANEL_IMPL_H_
#define _PANEL_IMPL_H_

#include "panel.h"

#include <sys/queue.h>

#define DECK_HEAD(head)         TAILQ_HEAD(head, __panel)
#define DECK_ENTRY              TAILQ_ENTRY(__panel)


/*
* Panels are just curses windows with Z-order added.
* See update_panels() for details.
*/
struct __panel {
       WINDOW *win;
       char *user;
       DECK_ENTRY zorder;
};


/* Deck of panels in Z-order from bottom to top. */
DECK_HEAD(deck);
extern struct deck _deck __dso_hidden;

/* Fake stdscr panel at the bottom, not user visible */
extern PANEL _stdscr_panel __dso_hidden;


/*
* Hidden panels are not in the deck.  <sys/queue.h> macros don't have
* a concept of an entry not on the list, so provide a kludge that
* digs into internals.
*/
#define TAILQ_REMOVE_NP(head, elm, field) do {  \
       TAILQ_REMOVE((head), (elm), field);     \
       (elm)->field.tqe_next = NULL;           \
       (elm)->field.tqe_prev = NULL;           \
} while (0)

#define TAILQ_LINKED_NP(elm, field) \
       (((elm)->field.tqe_prev) != NULL)


#define DECK_INSERT_TOP(p) do {                                 \
       TAILQ_INSERT_TAIL(&_deck, (p), zorder);                 \
} while (0)

#define DECK_INSERT_BOTTOM(p) do {                              \
       TAILQ_INSERT_AFTER(&_deck, &_stdscr_panel, (p), zorder); \
} while (0)

#define DECK_REMOVE(p) do {                                     \
       TAILQ_REMOVE_NP(&_deck, (p), zorder);                   \
} while (0)


#define PANEL_ABOVE(p)          (TAILQ_NEXT((p), zorder))
#define PANEL_BELOW(p)          (TAILQ_PREV((p), deck, zorder))
#define PANEL_HIDDEN(p)         (!TAILQ_LINKED_NP((p), zorder))

#define FOREACH_PANEL(var)      TAILQ_FOREACH(var, &_deck, zorder)

#endif  /* _PANEL_IMPL_H_ */