/*
 * This file is part of firk's window manager for x11 (fwm)
 * Copyright (C) 2016-2021 firk <firk@cantconnect.ru>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <errno.h>
#include <assert.h>
#include "main.h"
#include "base.h"
#include "config.h"
#include "winlist.h"

#define HT_SIZE (MAX_TOTAL_WINDOWS/3+1)
static WInfo  wlist[MAX_TOTAL_WINDOWS];
static int    numwlist = 0;
static WInfo *freelist;
static WInfo *ht[HT_SIZE];

extern WInfo * WInfo_new(Window window) {
  WInfo * wi;
  unsigned int h;

  h = ((unsigned long)window) % HT_SIZE;
  for(wi=ht[h]; wi; wi=wi->wdb.next) assert(wi->window!=window);

  if(wi = freelist) freelist = wi->wdb.next;
  else if(numwlist<MAX_TOTAL_WINDOWS) { wi = wlist+numwlist; numwlist++; }
  else return NULL;
  assert(!wi->wdb.self);
  bzero(wi, sizeof(*wi));
  wi->wdb.self = wi;
  wi->window = window;
  wi->wdb.next = ht[h];
  ht[h] = wi;
  return wi;
}

extern WInfo * WInfo_search(Window window) {
  WInfo * wi;
  unsigned int h;

  h = ((unsigned long)window) % HT_SIZE;
  for(wi=ht[h]; wi; wi=wi->wdb.next) {
    assert(wi->wdb.self==wi);
    if(wi->window==window) return wi;
  }
  return NULL;
}

extern void WInfo_delete(WInfo * wi) {
  WInfo **pwi, *cwi;
  unsigned int h;

  assert(wi);
  assert(wi->wdb.self==wi);
  assert(!wi->wdb.list);
  h = ((unsigned long)wi->window) % HT_SIZE;
  for(pwi=ht+h; cwi=*pwi; pwi=&cwi->wdb.next) if(cwi==wi) {
    *pwi = wi->wdb.next;
    bzero(wi, sizeof(*wi));
    wi->wdb.next = freelist;
    freelist = wi;
    return;
  }
  assert(!"deleting wi not in list");
}

static void wl_remove_wi(WList * wl, WInfo * wi) {
  WInfo *tb, *tt;
  assert(wl->bottom && wl->top);
  tb = wi->wdb.to_bottom;
  tt = wi->wdb.to_top;
  if(tb) {
    assert(wl->bottom!=wi);
    assert(tb->wdb.to_top==wi);
    tb->wdb.to_top = tt;
  } else {
    assert(wl->bottom==wi);
    wl->bottom = tt;
  }
  if(tt) {
    assert(wl->top!=wi);
    assert(tt->wdb.to_bottom==wi);
    tt->wdb.to_bottom = tb;
  } else {
    assert(wl->top==wi);
    wl->top = tb;
  }
  wi->wdb.to_bottom = wi->wdb.to_top = NULL;
  wi->wdb.list = NULL;
}

extern void WList_raise_window(WList * wl, WInfo * wi) {
  WInfo * cwi;
  assert(wi);
  assert(wi->wdb.self==wi);
  if(wi->wdb.list) {
    assert(wi->wdb.list==wl);
    if(wl->top==wi) return;
    wl_remove_wi(wl, wi);
  }
  assert(!wi->wdb.to_top && !wi->wdb.to_bottom);
  if(wi->wdb.to_bottom = cwi = wl->top) {
    assert(wl->bottom);
    assert(!cwi->wdb.to_top);
    cwi->wdb.to_top = wi;
  } else {
    assert(!wl->bottom);
    wl->bottom = wi;
  }
  wl->top = wi;
  wi->wdb.list = wl;
}

extern void WList_remove_window(WList * wl, WInfo * wi) {
  assert(wi);
  assert(wi->wdb.self==wi);
  assert(wi->wdb.list==wl);
  wl_remove_wi(wl, wi);
}

extern void WList_activate(WList * wl, Window top, Window bottom) {
  /* TODO: this function does not update focus_num and other taskbar.c vars;
           this function does not send TAKE_FOCUS event tonew focused window;
           also this function is not used currently;
     TODO: reorganize code */
  WInfo * wi;
  Window order[MAX_TOTAL_WINDOWS+2];
  int n;
  order[0] = top;
  for(n=1, wi=wl->top; wi; n++, wi=wi->wdb.to_bottom) {
    assert(n<=MAX_TOTAL_WINDOWS);
    order[n] = wi->window;
  }
  assert(n<=MAX_TOTAL_WINDOWS+1);
  order[n++] = bottom;
  XRestackWindows(display, order, n);
}