/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * Copyright (©) 2001,2007 Mark Wedel & Crossfire Development Team
 * Copyright (©) 1992,2007 Frank Tore Johansen
 * 
 * Deliantra 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 3 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.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 *
 * The authors can be reached via e-mail to <support@deliantra.net>
 */

#include <cmath>

#include <global.h>
#include <living.h>
#include <spells.h>
#include <skills.h>
#include <tod.h>

#include <sproto.h>

/* Want this regardless of rplay. */
#include <sounds.h>

/**
 * Check if op should abort moving victim because of it's race or slaying.
 * Returns 1 if it should abort, returns 0 if it should continue.
 */
int
should_director_abort (object *op, object *victim)
{
  int arch_flag, name_flag, race_flag;

  /* Get flags to determine what of arch, name, and race should be checked.
   * This is stored in subtype, and is a bitmask, the LSB is the arch flag,
   * the next is the name flag, and the last is the race flag. Also note,
   * if subtype is set to zero, that also goes to defaults of all affecting
   * it. Examples:
   * subtype 1: only arch
   * subtype 3: arch or name
   * subtype 5: arch or race
   * subtype 7: all three
   */
  if (op->subtype)
    {
      arch_flag = op->subtype & 1;
      name_flag = op->subtype & 2;
      race_flag = op->subtype & 4;
    }
  else
    {
      arch_flag = 1;
      name_flag = 1;
      race_flag = 1;
    }

  /* If the director has race set, only affect objects with a arch, 
   * name or race that matches.
   */
  if ((op->race) &&
      ((!(victim->arch && arch_flag && victim->arch->archname) || op->race != victim->arch->archname)) &&
      ((!(victim->name && name_flag) || op->race != victim->name)) &&
      ((!(victim->race && race_flag) || op->race != victim->race)))
    return 1;

  /* If the director has slaying set, only affect objects where none
   * of arch, name, or race match.
   */
  if ((op->slaying) && (((victim->arch && arch_flag && victim->arch->archname && op->slaying == victim->arch->archname))) ||
                        ((victim->name && name_flag && op->slaying == victim->name)) ||
                        ((victim->race && race_flag && op->slaying == victim->race)))
    return 1;

  return 0;
}

/**
 * This handles a player dropping money on an altar to identify stuff.
 * It'll identify marked item, if none all items up to dropped money.
 * Return value: 1 if money was destroyed, 0 if not.
 */
static int
apply_id_altar (object *money, object *altar, object *pl)
{
  dynbuf_text &buf = msg_dynbuf; buf.clear ();

  if (!pl || pl->type != PLAYER)
    return 0;

  /* Check for MONEY type is a special hack - it prevents 'nothing needs
   * identifying' from being printed out more than it needs to be.
   */
  if (!check_altar_sacrifice (altar, money) || money->type != MONEY)
    return 0;

  /* if the player has a marked item, identify that if it needs to be
   * identified. If it doesn't, then go through the player inventory.
   */
  if (object *marked = find_marked_object (pl))
    if (!QUERY_FLAG (marked, FLAG_IDENTIFIED) && need_identify (marked))
      {
        if (operate_altar (altar, &money))
          {
            identify (marked);

            buf.printf ("You have %s.\r", long_desc (marked, pl));
            if (marked->msg)
              buf << "The item has a story:\r" << marked->msg << "\n\n";

            return !money;
          }
      }

  for (object *id = pl->inv; id; id = id->below)
    {
      if (!QUERY_FLAG (id, FLAG_IDENTIFIED) && !id->invisible && need_identify (id))
        {
          if (operate_altar (altar, &money))
            {
              identify (id);

              buf.printf ("You have %s.\r", long_desc (id, pl));
              if (id->msg)
                buf << "The item has a story:\r" << id->msg << "\n\n";

              /* If no more money, might as well quit now */
              if (!money || !check_altar_sacrifice (altar, money))
                break;
            }
          else
            {
              LOG (llevError, "check_id_altar:  Couldn't do sacrifice when we should have been able to\n");
              break;
            }
        }
    }

  if (buf.empty ())
    pl->failmsg ("You have nothing that needs identifying");
  else
    pl->contr->infobox (MSG_CHANNEL ("identify"), buf);

  return !money;
}

/**
 * This checks whether the object has a "on_use_yield" field, and if so generated and drops
 * matching item.
 **/
void
handle_apply_yield (object *tmp)
{
  if (shstr_tmp yield = tmp->kv (shstr_on_use_yield))
    archetype::get (yield)->insert_at (tmp, tmp, INS_BELOW_ORIGINATOR);
}

/**
 * Handles applying a potion.
 */
int
apply_potion (object *op, object *tmp)
{
  int got_one = 0, i;
  object *force = 0, *floor = 0;

  floor = GET_MAP_OB (op->map, op->x, op->y);

  if (get_map_flags (op->map, NULL, op->x, op->y, NULL, NULL) & P_SAFE)
    {
      op->failmsg ("Gods prevent you from using this here, it's sacred ground!");

      CLEAR_FLAG (tmp, FLAG_APPLIED);
      return 0;
    }

  if (op->type == PLAYER)
    if (!QUERY_FLAG (tmp, FLAG_IDENTIFIED))
      identify (tmp);

  handle_apply_yield (tmp);

  /* Potion of restoration - only for players */
  if (op->type == PLAYER && (tmp->attacktype & AT_DEPLETE))
    {
      object *depl;
      archetype *at;

      if (QUERY_FLAG (tmp, FLAG_CURSED) || QUERY_FLAG (tmp, FLAG_DAMNED))
        {
          op->drain_stat ();
          op->update_stats ();
          tmp->decrease ();
          return 1;
        }

      if (!(at = archetype::find (ARCH_DEPLETION)))
        {
          LOG (llevError, "Could not find archetype depletion\n");
          return 0;
        }

      depl = present_arch_in_ob (at, op);

      if (depl)
        {
          for (i = 0; i < NUM_STATS; i++)
            if (depl->stats.stat (i))
              op->statusmsg (restore_msg[i]);

          depl->destroy ();
          op->update_stats ();
        }
      else
        op->statusmsg ("Your potion had no effect.");

      tmp->decrease ();
      return 1;
    }

  /* improvement potion - only for players */
  if (op->type == PLAYER && (tmp->attacktype & AT_GODPOWER))
    {
      for (i = 1; i < MIN (11, op->level); i++)
        {
          if (QUERY_FLAG (tmp, FLAG_CURSED) || QUERY_FLAG (tmp, FLAG_DAMNED))
            {
              if (op->contr->levhp[i] != 1)
                {
                  op->contr->levhp[i] = 1;
                  break;
                }

              if (op->contr->levsp[i] != 1)
                {
                  op->contr->levsp[i] = 1;
                  break;
                }

              if (op->contr->levgrace[i] != 1)
                {
                  op->contr->levgrace[i] = 1;
                  break;
                }
            }
          else
            {
              if (op->contr->levhp[i] < 9)
                {
                  op->contr->levhp[i] = 9;
                  break;
                }

              if (op->contr->levsp[i] < 6)
                {
                  op->contr->levsp[i] = 6;
                  break;
                }

              if (op->contr->levgrace[i] < 3)
                {
                  op->contr->levgrace[i] = 3;
                  break;
                }
            }
        }

      /* Just makes checking easier */
      if (i < MIN (11, op->level))
        got_one = 1;

      if (!QUERY_FLAG (tmp, FLAG_CURSED) && !QUERY_FLAG (tmp, FLAG_DAMNED))
        {
          if (got_one)
            {
              op->update_stats ();
              op->statusmsg ("The Gods smile upon you and remake you "
                             "a little more in their image. "
                             "You feel a little more perfect.", NDI_GREEN);
            }
          else
            op->statusmsg ("The potion had no effect - you are already perfect.");
        }
      else
        {                       /* cursed potion */
          if (got_one)
            {
              op->update_stats ();
              op->failmsg ("The Gods are angry and punish you.");
            }
          else
            op->statusmsg ("You are fortunate that you are so pathetic.", NDI_DK_ORANGE);
        }

      tmp->decrease ();
      return 1;
    }


  /* A potion that casts a spell.  Healing, restore spellpoint (power potion)
   * and heroism all fit into this category.  Given the spell object code,
   * there is no limit to the number of spells that potions can be cast,
   * but direction is problematic to try and imbue fireball potions for example.
   */
  if (tmp->inv)
    {
      if (QUERY_FLAG (tmp, FLAG_CURSED) || QUERY_FLAG (tmp, FLAG_DAMNED))
        {
          op->failmsg ("Yech! Your lungs are on fire!");
          create_exploding_ball_at (op, op->level);
        }
      else
        cast_spell (op, tmp, op->facing, tmp->inv, NULL);

      tmp->decrease ();

      /* if youre dead, no point in doing this... */
      if (!QUERY_FLAG (op, FLAG_REMOVED))
        op->update_stats ();

      return 1;
    }

  /* Deal with protection potions */
  force = NULL;
  for (i = 0; i < NROFATTACKS; i++)
    {
      if (tmp->resist[i])
        {
          if (!force)
            force = get_archetype (FORCE_NAME);

          memcpy (force->resist, tmp->resist, sizeof (tmp->resist));
          force->type = POTION_EFFECT;
          break;                /* Only need to find one protection since we copy entire batch */
        }
    }

  /* This is a protection potion */
  if (force)
    {
      /* cursed items last longer */
      if (QUERY_FLAG (tmp, FLAG_CURSED) || QUERY_FLAG (tmp, FLAG_DAMNED))
        {
          force->stats.food *= 10;
          for (i = 0; i < NROFATTACKS; i++)
            if (force->resist[i] > 0)
              force->resist[i] = -force->resist[i];     /* prot => vuln */
        }

      force->speed_left = -1;
      force = insert_ob_in_ob (force, op);
      CLEAR_FLAG (tmp, FLAG_APPLIED);
      SET_FLAG (force, FLAG_APPLIED);
      change_abil (op, force);
      tmp->decrease ();
      return 1;
    }

  /* Only thing left are the stat potions */
  if (op->type == PLAYER)
    {                           /* only for players */
      if ((QUERY_FLAG (tmp, FLAG_CURSED)
           || QUERY_FLAG (tmp, FLAG_DAMNED))
          && tmp->value != 0)
        CLEAR_FLAG (tmp, FLAG_APPLIED);
      else
        SET_FLAG (tmp, FLAG_APPLIED);

      if (!change_abil (op, tmp))
        op->statusmsg ("Nothing happened.");
    }

  /* CLEAR_FLAG is so that if the character has other potions
   * that were grouped with the one consumed, his
   * stat will not be raised by them.  fix_player just clears
   * up all the stats.
   */
  CLEAR_FLAG (tmp, FLAG_APPLIED);
  op->update_stats ();
  tmp->decrease ();
  return 1;
}

/****************************************************************************
 * Weapon improvement code follows
 ****************************************************************************/

/**
 * This function just checks whether who can handle equipping an item
 * with item_power.
 */

bool
check_item_power (object *who, int item_power)
{
  if (who->type == PLAYER
      && item_power
      && item_power + who->contr->item_power > settings.item_power_factor * who->level)
    return false;
  else
    return true;
}

/**
 * This returns the sum of nrof of item (arch name).
 */
static int
check_item (object *op, shstr_cmp item)
{
  int count = 0;

  if (!item)
    return 0;

  for (op = op->below; op; op = op->below)
    if (op->arch->archname == item)
      if (!QUERY_FLAG (op, FLAG_CURSED) && !QUERY_FLAG (op, FLAG_DAMNED)
          && /* Loophole bug? -FD- */  !QUERY_FLAG (op, FLAG_UNPAID))
        count += op->number_of ();

  return count;
}

/**
 * This removes 'nrof' of what item->slaying says to remove.
 * op is typically the player, which is only
 * really used to determine what space to look at.
 * Modified to only eat 'nrof' of objects.
 */
static void
eat_item (object *op, shstr_cmp item, uint32 nrof)
{
  object *prev;

  prev = op;
  op = op->below;

  while (op)
    {
      if (op->arch->archname == item)
        {
          if (op->nrof >= nrof)
            {
              op->decrease (nrof);
              return;
            }
          else
            {
              op->decrease (nrof);
              nrof -= op->nrof;
            }

          op = prev;
        }

      prev = op;
      op = op->below;
    }
}

/**
 * Returns how many items of type improver->slaying there are under op.
 * Will display a message if none found, and 1 if improver->slaying is NULL.
 */
static int
check_sacrifice (object *op, const object *improver)
{
  int count = 0;

  if (improver->slaying)
    {
      count = check_item (op, improver->slaying);
      if (count < 1)
        {
          op->failmsg (format ("The gods want more %ss", &improver->slaying));
          return 0;
        }
    }
  else
    count = 1;

  return count;
}

/**
 * Actually improves the weapon, and tells user.
 */
static int
improve_weapon_stat (object *op, object *improver, object *weapon, sint8 &stat, int sacrifice_count, const char *statname)
{
  stat += sacrifice_count;
  weapon->last_eat++;
  improver->decrease ();

  /* So it updates the players stats and the window */
  op->update_stats ();

  op->statusmsg (format (
    "Your sacrifice was accepted.\n"
    "Weapon's bonus to %s improved by %d.",
    statname, sacrifice_count
  ));

  return 1;
}

/* Types of improvements, hidden in the sp field. */
#define IMPROVE_PREPARE  1
#define IMPROVE_DAMAGE   2
#define IMPROVE_WEIGHT   3
#define IMPROVE_ENCHANT  4
#define IMPROVE_STR      5
#define IMPROVE_DEX      6
#define IMPROVE_CON      7
#define IMPROVE_WIS      8
#define IMPROVE_CHA      9
#define IMPROVE_INT     10
#define IMPROVE_POW     11

/**
 * This does the prepare weapon scroll.
 * Checks for sacrifice, and so on.
 */
int
prepare_weapon (object *op, object *improver, object *weapon)
{
  int sacrifice_count, i;
  char buf[MAX_BUF];

  if (weapon->level != 0)
    {
      op->failmsg ("Weapon is already prepared!");
      return 0;
    }

  for (i = 0; i < NROFATTACKS; i++)
    if (weapon->resist[i])
      break;

  /* If we break out, i will be less than nrofattacks, preventing
   * improvement of items that already have protections.
   */
  if (i < NROFATTACKS || weapon->stats.hp ||    /* regeneration */
      (weapon->stats.sp && weapon->type == WEAPON) ||   /* sp regeneration */
      weapon->stats.exp ||      /* speed */
      weapon->stats.ac)         /* AC - only taifu's I think */
    {
      op->failmsg ("You cannot prepare magic weapons. "
                   "H<A weapon is considered magical if it changes regeneration, "
                   "speed or ac, or has other protections.>");
      return 0;
    }

  sacrifice_count = check_sacrifice (op, improver);
  if (sacrifice_count <= 0)
    return 0;

  weapon->level = isqrt (sacrifice_count);
  eat_item (op, improver->slaying, sacrifice_count);

  op->statusmsg (format (
    "Your sacrifice was accepted."
    "Your *%s may be improved %d times.",
    &weapon->name, weapon->level
  ));

  sprintf (buf, "%s's %s", &op->name, &weapon->name);
  weapon->name = weapon->name_pl = buf;
  weapon->nrof = 0;             /*  prevents preparing n weapons in the same
                                   slot at once! */
  improver->decrease ();
  weapon->last_eat = 0;
  return 1;
}

/**
 * Does the dirty job for 'improve weapon' scroll, prepare or add something.
 * This is the new improve weapon code.
 * Returns 0 if it was not able to work for some reason.
 *
 * Checks if weapon was prepared, if enough potions on the floor, ...
 *
 * We are hiding extra information about the weapon in the level and
 * last_eat numbers for an object.  Hopefully this won't break anything ?? 
 * level == max improve last_eat == current improve
 */
int
improve_weapon (object *op, object *improver, object *weapon)
{
  int sacrifice_count, sacrifice_needed = 0;

  if (improver->stats.sp == IMPROVE_PREPARE)
    return prepare_weapon (op, improver, weapon);

  if (weapon->level == 0)
    {
      op->failmsg (
        "This weapon has not been prepared."
        " H<You first have to prepare a weapon with a prepare weapon scroll.>");
      return 0;
    }

  if (weapon->last_eat >= weapon->level   // improvements used up
      || weapon->item_power >= 100)       // or item_power >= arbitrary limit of 100
    {
      op->failmsg ("This weapon cannot be improved any more.");
      return 0;
    }

  if (QUERY_FLAG (weapon, FLAG_APPLIED)
      && !check_item_power (op, weapon->item_power + 1))
    {
      op->failmsg ("Improving the weapon will make it too "
                    "powerful for you to use. Unready it if you "
                    "really want to improve it.");
      return 0;
    }

  /* This just increases damage by 5 points, no matter what.  No sacrifice
   * is needed.  Since stats.dam is now a 16 bit value and not 8 bit,
   * don't put any maximum value on damage - the limit is how much the
   * weapon  can be improved.
   */
  if (improver->stats.sp == IMPROVE_DAMAGE)
    {
      weapon->stats.dam += 5;
      weapon->weight += 5000;   /* 5 KG's */
      op->statusmsg (format ("Damage has been increased by 5 to %d.", weapon->stats.dam));
      weapon->last_eat++;

      weapon->item_power++;
      improver->decrease ();
      return 1;
    }

  if (improver->stats.sp == IMPROVE_WEIGHT)
    {
      /* Reduce weight by 20% */
      weapon->weight = (weapon->weight * 8) / 10;
      if (weapon->weight < 1)
        weapon->weight = 1;

      op->statusmsg (format ("Weapon weight reduced to %6.1fkg.", (float) weapon->weight / 1000.0));
      weapon->last_eat++;
      weapon->item_power++;
      improver->decrease ();
      return 1;
    }

  if (improver->stats.sp == IMPROVE_ENCHANT)
    {
      weapon->magic++;
      weapon->last_eat++;
      op->statusmsg (format ("Weapon magic increased to %d.", weapon->magic));
      improver->decrease ();
      weapon->item_power++;
      return 1;
    }

  sacrifice_needed = weapon->stats.Str + weapon->stats.Int + weapon->stats.Dex +
    weapon->stats.Pow + weapon->stats.Con + weapon->stats.Cha + weapon->stats.Wis;

  if (sacrifice_needed < 1)
    sacrifice_needed = 1;
  sacrifice_needed *= 2;

  sacrifice_count = check_sacrifice (op, improver);
  if (sacrifice_count < sacrifice_needed)
    {
      op->failmsg (format ("You need at least %d %s.", sacrifice_needed, &improver->slaying));
      return 0;
    }

  eat_item (op, improver->slaying, sacrifice_needed);
  weapon->item_power++;

  switch (improver->stats.sp)
    {
      case IMPROVE_STR: return improve_weapon_stat (op, improver, weapon, weapon->stats.Str, 1, "strength");
      case IMPROVE_DEX: return improve_weapon_stat (op, improver, weapon, weapon->stats.Dex, 1, "dexterity");
      case IMPROVE_CON: return improve_weapon_stat (op, improver, weapon, weapon->stats.Con, 1, "constitution");
      case IMPROVE_WIS: return improve_weapon_stat (op, improver, weapon, weapon->stats.Wis, 1, "wisdom");
      case IMPROVE_CHA: return improve_weapon_stat (op, improver, weapon, weapon->stats.Cha, 1, "charisma");
      case IMPROVE_INT: return improve_weapon_stat (op, improver, weapon, weapon->stats.Int, 1, "intelligence");
      case IMPROVE_POW: return improve_weapon_stat (op, improver, weapon, weapon->stats.Pow, 1, "power");
      default:
        op->failmsg ("Unknown improvement type.");
    }

  LOG (llevError, "improve_weapon: Got to end of function\n");
  return 0;
}

/**
 * Handles the applying of improve/prepare/enchant weapon scroll.
 * Checks a few things (not on a non-magic square, marked weapon, ...),
 * then calls improve_weapon to do the dirty work.
 */
int
check_improve_weapon (object *op, object *tmp)
{
  object *otmp;

  if (op->type != PLAYER)
    return 0;

  if (!QUERY_FLAG (op, FLAG_WIZCAST) && (get_map_flags (op->map, NULL, op->x, op->y, NULL, NULL) & P_NO_MAGIC))
    {
      op->failmsg ("Something blocks the magic of the scroll!");
      return 0;
    }

  otmp = find_marked_object (op);

  if (!otmp)
    {
      op->failmsg ("You need to mark a weapon object. H<Use the mark command or the mark option from the item popup menu.>");
      return 0;
    }

  if (otmp->type != WEAPON && otmp->type != BOW)
    {
      op->failmsg ("Marked item is not a weapon or bow!");
      return 0;
    }

  op->statusmsg ("Applied weapon builder.");

  improve_weapon (op, tmp, otmp);
  esrv_send_item (op, otmp);
  return 1;
}

/**
 * This code deals with the armour improvment scrolls.
 * Change limits on improvement - let players go up to
 * +5 no matter what level, but they are limited by item
 * power.
 * Try to use same improvement code as in the common/treasure.c
 * file, so that if you make a +2 full helm, it will be just
 * the same as one you find in a shop.
 *
 * deprecated comment:
 * this code is by b.t. (thomas@nomad.astro.psu.edu) -
 * only 'enchantment' of armour is possible - improving
 * the stats of a player w/ armour as well as a weapon
 * will probably horribly unbalance the game. Magic enchanting
 * depends on the level of the character - ie the plus
 * value (magic) of the armour can never be increased beyond
 * the level of the character / 10 -- rounding upish, nor may
 * the armour value of the piece of equipment exceed either 
 * the users level or 90)
 * Modified by MSW for partial resistance.  Only support
 * changing of physical area right now.
 */
int
improve_armour (object *op, object *improver, object *armour)
{
  object *tmp;

  if (armour->magic >= settings.armor_max_enchant)
    {
      op->failmsg ("This armour can not be enchanted any further!");
      return 0;
    }

  /* Dealing with random artifact armor is a lot trickier (in terms of value, weight,
   * etc), so take the easy way out and don't worry about it.
   * Note - maybe add scrolls which make the random artifact versions (eg, armour
   * of gnarg and what not?)
   */
  if (armour->title)
    {
      op->failmsg ("This armour will not accept further enchantment.");
      return 0;
    }

  /* Split objects if needed. Can't insert tmp until the
   * end of this function - otherwise it will just re-merge.
   */
  tmp = armour->nrof > 1 ? armour->split (armour->nrof - 1) : 0;

  armour->magic++;

  if (!settings.armor_speed_linear)
    {
      int base = 100;
      int pow = 0;

      while (pow < armour->magic)
        {
          base = base - (base * settings.armor_speed_improvement) / 100;
          pow++;
        }

      ARMOUR_SPEED (armour) = (ARMOUR_SPEED (armour->arch) * base) / 100;
    }
  else
    ARMOUR_SPEED (armour) = (ARMOUR_SPEED (armour->arch) * (100 + armour->magic * settings.armor_speed_improvement)) / 100;

  if (!settings.armor_weight_linear)
    {
      int base = 100;
      int pow = 0;

      while (pow < armour->magic)
        {
          base = base - (base * settings.armor_weight_reduction) / 100;
          pow++;
        }

      armour->weight = (armour->arch->weight * base) / 100;
    }
  else
    armour->weight = (armour->arch->weight * (100 - armour->magic * settings.armor_weight_reduction)) / 100;

  if (armour->weight <= 0)
    {
      LOG (llevInfo, "Warning: enchanted armours can have negative weight\n.");
      armour->weight = 1;
    }

  armour->item_power = get_power_from_ench (armour->arch->item_power + armour->magic);

  if (op->type == PLAYER)
    {
      esrv_send_item (op, armour);

      if (QUERY_FLAG (armour, FLAG_APPLIED))
        op->update_stats ();
    }

  improver->decrease ();

  if (tmp)
    op->insert (tmp);

  return 1;
}

/*
 * convert_item() returns 1 if anything was converted, 0 if the item was not
 * what the converter wants, -1 if the converter is broken.
 *
 * Takes one type of items and makes another.
 * converter is the object that is doing the conversion.
 * item is the object that triggered the converter - if it is not
 * what the converter wants, this will not do anything.
 */
static int
convert_item (object *item, object *converter)
{
  sint64 nr, price_in;

  if (item->flag [FLAG_UNPAID])
    return 0;
  
  shstr conv_from    = converter->slaying;
  archetype *conv_to = converter->other_arch;
  sint64 need        = converter->stats.food;
  sint64 give        = converter->stats.sp;

  /* We make some assumptions - we assume if it takes money as it type,
   * it wants some amount.  We don't make change (ie, if something costs
   * 3 gp and player drops a platinum, tough luck)
   */
  if (conv_from == shstr_money)
    {
      if (item->type != MONEY)
        return 0;

      nr = sint64 (item->nrof) * item->value / need;
      if (!nr)
        return 0;

      converter->play_sound (sound_find ("shop_buy"));

      sint64 cost = (nr * need + item->value - 1) / item->value;

      item->decrease (cost);

      price_in = cost * item->value;
    }
  else
    {
      if (item->type == PLAYER
          || conv_from != item->arch->archname
          || (need && need > (uint16) item->nrof))
        return 0;

      converter->play_sound (sound_find ("convert_item"));

      if (need)
        {
          nr = sint64 (item->nrof) / need;
          item->decrease (nr * need);
          price_in = nr * need * item->value;
        }
      else
        {
          price_in = item->value;
          item->destroy ();
        }
    }

  if (converter->inv)
    {
      object *ob;
      int i;
      object *ob_to_copy;

      /* select random object from inventory to copy */
      ob_to_copy = converter->inv;
      for (ob = converter->inv->below, i = 1; ob; ob = ob->below, i++)
        if (rndm (0, i) == 0)
          ob_to_copy = ob;

      item = ob_to_copy->deep_clone ();
      CLEAR_FLAG (item, FLAG_IS_A_TEMPLATE);
      unflag_inv (item, FLAG_IS_A_TEMPLATE);
    }
  else
    {
      if (!conv_to)
        {
          LOG (llevError, "move_creator: Converter doesn't have other arch set: %s (%s, %d, %d)\n",
               &converter->name, &converter->map->path, converter->x, converter->y);
          return -1;
        }

      item = object_create_arch (conv_to);
      fix_generated_item (item, converter, 0, 0, GT_MINIMAL);
    }

  if (give)
    item->nrof = give;

  if (nr)
    item->nrof *= nr;

  if (converter->flag [FLAG_PRECIOUS])
    SET_FLAG (item, FLAG_UNPAID);

  if (is_in_shop (converter)) 
    {
      // converters on shop floors don't work anymore, bug lets check for it
      // and report in case someone still does it.
      LOG (llevDebug, "ITEMBUG: broken converter, converters on shop floor don't work: %s\n",
           converter->debug_desc ());
      SET_FLAG (item, FLAG_UNPAID);
    }
  else if (price_in < sint64 (item->nrof) * item->value)
    {
      LOG (llevDebug, "converter output price higher than input: %s at %s (%d, %d) in value %d, out value %d for %s\n",
           &converter->name, &converter->map->path, converter->x, converter->y, price_in, item->nrof * item->value, &item->name);
      /**
       * elmex: we are going to let the game continue, as the mapcreator 
       * hopefully had something in mind when doing this.
       */
    }

  // elmex: only identify if we need to, for example so that generated money doesn't
  //        get an 'identified' flag so easily.
  if (need_identify (item))
    identify (item);

  insert_ob_in_map_at (item, converter->map, converter, 0, converter->x, converter->y);
  return 1;
}

/**
 * Handle apply on containers. 
 * By Eneq(@csd.uu.se).
 * Moved to own function and added many features [Tero.Haatanen@lut.fi]
 * added the alchemical cauldron to the code -b.t.
 */
int
apply_container (object *op, object *sack)
{
  if (op->type != PLAYER || !op->contr->ns)
    return 0;                   /* This might change */

  if (!sack || sack->type != CONTAINER)
    {
      LOG (llevError, "apply_container: %s is not container!\n", sack ? &sack->name : "[nullobject]");
      return 0;
    }

  op->contr->last_used = 0;

  if (sack->env && sack->env != op)
    {
      op->failmsg ("You must put it onto the floor or into your inventory first.");
      return 1;
    }

  // already applied == open on ground, or open in inv, or active in inv
  if (sack->flag [FLAG_APPLIED])
    {
      if (op->container == sack)
        {
          // open on ground or inv, so close
          op->close_container ();
          return 1;
        }
      else if (!sack->env)
        {
          // active, but not ours: some other player has opened it
          op->failmsg (format ("Somebody else is using the %s already.", query_name (sack)));
          return 1;
        }

      // fall through to opening it (active in inv)
    }
  else if (sack->env)
    {
      // it is in our env, so activate it, do not open yet
      op->close_container ();
      sack->flag [FLAG_APPLIED] = 1;
      esrv_update_item (UPD_FLAGS, op, sack);
      op->statusmsg (format ("You ready %s.", query_name (sack)));
      return 1;
    }

  // it's locked?
  if (sack->slaying)
    {
      if (object *tmp = find_key (op, op, sack))
        op->statusmsg (format ("You unlock %s with %s.", query_name (sack), query_name (tmp)));
      else
        {
          op->statusmsg (format ("You don't have the key to unlock %s.", query_name (sack)));
          return 1;
        }
    }

  op->open_container (sack);

  return 1;
}

/**
 * Handles dropping things on altar.
 * Returns true if sacrifice was accepted.
 */
static int
apply_altar (object *altar, object *sacrifice, object *originator)
{
  /* Only players can make sacrifices on spell casting altars. */
  if (altar->inv && (!originator || originator->type != PLAYER))
    return 0;

  if (operate_altar (altar, &sacrifice))
    {
      /* Simple check.  Unfortunately, it means you can't cast magic bullet
       * with an altar.  We call it a Potion - altars are stationary - it
       * is up to map designers to use them properly.
       */
      if (altar->inv && altar->inv->type == SPELL)
        {
          originator->statusmsg (format ("The altar casts %s.", &altar->inv->name));
          cast_spell (originator, altar, 0, altar->inv, NULL);
          /* If it is connected, push the button. Fixes some problems with
           * old maps.
           */

/*	    push_button (altar);*/
        }
      else
        {
          altar->value = 1;     /* works only once */
          push_button (altar, originator);
        }

      return !sacrifice;
    }
  else
    return 0;
}

/**
 * Handles 'movement' of shop mats.
 * Returns 1 if 'op' was destroyed, 0 if not.
 * Largely re-written to not use nearly as many gotos, plus
 * some of this code just looked plain out of date.
 * MSW 2001-08-29
 */
int
apply_shop_mat (object *shop_mat, object *op)
{
  int rv = 0;
  double opinion;
  object *tmp, *next;

  SET_FLAG (op, FLAG_NO_APPLY); /* prevent loops */

  bool has_unpaid = false;

  // quite inefficient to do this here twice, but the api doesn'T lend itself to
  // a quick and small change :(
  for (object::depth_iterator item = op->begin (); item != op->end (); ++item)
    if (item->flag [FLAG_UNPAID])
      {
        has_unpaid = true;
        break;
      }

  if (!op->is_player ())
    {
      /* Remove all the unpaid objects that may be carried here.
       * This could be pets or monsters that are somehow in
       * the shop.
       */
      for (tmp = op->inv; tmp; tmp = next)
        {
          next = tmp->below;

          if (QUERY_FLAG (tmp, FLAG_UNPAID))
            {
              int i = find_free_spot (tmp, op->map, op->x, op->y, 1, 9);

              if (i >= 0)
                tmp->move (i);
            }
        }

      /* Don't teleport things like spell effects */
      if (QUERY_FLAG (op, FLAG_NO_PICK))
        return 0;

      /* unpaid objects, or non living objects, can't transfer by
       * shop mats.  Instead, put it on a nearby space.
       */
      if (QUERY_FLAG (op, FLAG_UNPAID) || !QUERY_FLAG (op, FLAG_ALIVE))
        {
          /* Somebody dropped an unpaid item, just move to an adjacent place. */
          int i = find_free_spot (op, op->map, op->x, op->y, 1, 9);

          if (i != -1)
            rv = transfer_ob (op, op->x + freearr_x[i], op->y + freearr_y[i], 0, shop_mat);

          return 0;
        }

      /* Removed code that checked for multipart objects - it appears that
       * the teleport function should be able to handle this just fine.
       */
      rv = teleport (shop_mat, SHOP_MAT, op);
    }
  else if (can_pay (op) && get_payment (op))
    {
      /* this is only used for players */
      rv = teleport (shop_mat, SHOP_MAT, op);

      if (has_unpaid)
        op->contr->play_sound (sound_find ("shop_buy"));
      else if (is_in_shop (op))
        op->contr->play_sound (sound_find ("shop_enter"));
      else
        op->contr->play_sound (sound_find ("shop_leave"));

      if (shop_mat->msg)
        op->statusmsg (shop_mat->msg);
      /* This check below is a bit simplistic - generally it should be correct,
       * but there is never a guarantee that the bottom space on the map is
       * actually the shop floor.
       */
      else if (!rv && !is_in_shop (op))
        {
          opinion = shopkeeper_approval (op->map, op);

          op->statusmsg (
             opinion >= 0.90 ? "The shopkeeper gives you a friendly wave."
           : opinion >= 0.75 ? "The shopkeeper waves to you."
           : opinion >= 0.50 ? "The shopkeeper ignores you."
           :                   "The shopkeeper glares at you with contempt."
          );
        }
    }
  else
    {
      /* if we get here, a player tried to leave a shop but was not able
       * to afford the items he has. We try to move the player so that
       * they are not on the mat anymore
       */
      int i = find_free_spot (op, op->map, op->x, op->y, 1, 9);

      if (i == -1)
        LOG (llevError, "Internal shop-mat problem.\n");
      else
        {
          op->remove ();
          op->x += freearr_x[i];
          op->y += freearr_y[i];
          rv = insert_ob_in_map (op, op->map, shop_mat, 0) == NULL;
        }
    }

  CLEAR_FLAG (op, FLAG_NO_APPLY);
  return rv;
}

/**
 * Handles applying a sign.
 */
static void
apply_sign (object *op, object *sign, int autoapply)
{
  if (!op->is_player())
    return;

  if (sign->has_dialogue ())
    {
      op->statusmsg (format ("Maybe you should I<talk> to the %s instead?", &sign->name));
      return;
    }

  if (!sign->msg)
    {
      op->contr->infobox (MSG_CHANNEL ("examine"),
                          format ("T<%s>\n\n Nothing %sis written on it.",
                                  &sign->name,
                                  sign->name == sign->arch->name ? "" : "else "));
      return;
    }

  if (sign->stats.food)
    {
      if (sign->last_eat >= sign->stats.food)
        {
          if (!sign->move_on)
            op->failmsg ("You cannot read it anymore.");

          return;
        }

      if (!QUERY_FLAG (op, FLAG_WIZPASS))
        sign->last_eat++;
    }

  /* Sign or magic mouth?  Do we need to see it, or does it talk to us?
   * No way to know for sure.  The presumption is basically that if
   * move_on is zero, it needs to be manually applied (doesn't talk
   * to us).  
   */
  if (QUERY_FLAG (op, FLAG_BLIND) && !QUERY_FLAG (op, FLAG_WIZ) && !sign->move_on)
    {
      op->failmsg ("You are unable to read while blind!");
      return;
    }

  if (op->contr)
    if (client *ns = op->contr->ns)
      {
        if (sign->sound)
          ns->play_sound (sign->sound);
        else if (autoapply)
          ns->play_sound (sound_find ("msg_voice"));

        op->contr->infobox (MSG_CHANNEL ("examine"), format ("T<%s>\n\n%s", &sign->name, &sign->msg));
      }
}

static void
move_apply_hole (object *trap, object *victim)
{
  /* Hole not open? */
  if (trap->stats.wc > 0)
    return;

  /* Is this a multipart monster and not the head?  If so, return.
   * Processing will happen if the head runs into the pit
   */
  if (victim->head)
    return;

  // now find all possible locations and randomly pick one
  int dir = find_free_spot (victim, trap->map, EXIT_X (trap), EXIT_Y (trap), 0,
                            trap->range   >= 3 ? SIZEOFFREE3 + 1
                            : trap->range >= 2 ? SIZEOFFREE2 + 1
                            : trap->range >= 1 ? SIZEOFFREE1 + 1
                            :                    SIZEOFFREE0 + 1);

  if (dir < 0)
    return;

  victim->play_sound (trap->sound ? trap->sound : sound_find ("fall_hole"));
  victim->statusmsg ("You fall through the hole!", NDI_RED);

  transfer_ob (victim,
               EXIT_X (trap) + freearr_x[dir],
               EXIT_Y (trap) + freearr_y[dir],
               0, victim);
}

/**
 * 'victim' moves onto 'trap'
 * 'victim' leaves 'trap'
 * effect is determined by move_on/move_off of trap and move_type of victime.
 *
 * originator: Player, monster or other object that caused 'victim' to move
 * onto 'trap'.  Will receive messages caused by this action.  May be NULL.
 * However, some types of traps require an originator to function.
 */
void
move_apply (object *trap, object *victim, object *originator)
{
  static int recursion_depth = 0;

  /* Only exits affect DMs. */
  if (QUERY_FLAG (victim, FLAG_WIZPASS) && trap->type != EXIT && trap->type != SIGN)
    return;

  /* move_apply() is the most likely candidate for causing unwanted and
   * possibly unlimited recursion. 
   */
  /* The following was changed because it was causing perfeclty correct
   * maps to fail.  1)  it's not an error to recurse:
   * rune detonates, summoning monster.  monster lands on nearby rune.
   * nearby rune detonates.  This sort of recursion is expected and
   * proper.  This code was causing needless crashes. 
   */
  if (recursion_depth >= 500)
    {
      LOG (llevDebug, "WARNING: move_apply(): aborting recursion "
           "[trap arch %s, name %s; victim arch %s, name %s]\n", &trap->arch->archname, &trap->name, &victim->arch->archname, &victim->name);
      return;
    }

  recursion_depth++;
  if (trap->head)
    trap = trap->head;

  if (INVOKE_OBJECT (MOVE_TRIGGER, trap, ARG_OBJECT (victim), ARG_OBJECT (originator)))
    goto leave;

  switch (trap->type)
    {
      case PLAYERMOVER:
        if (trap->attacktype && (trap->level || victim->type != PLAYER) && !should_director_abort (trap, victim))
          {
            if (!trap->stats.maxsp)
              trap->stats.maxsp = 2;

            /* Is this correct?  From the docs, it doesn't look like it
             * should be divided by trap->speed
             */
            victim->speed_left = -FABS (trap->stats.maxsp * victim->speed / trap->speed);

            /* Just put in some sanity check.  I think there is a bug in the
             * above with some objects have zero speed, and thus the player
             * getting permanently paralyzed.
             */
            if (victim->speed_left < -50.f)
              victim->speed_left = -50.f;
            /*      LOG(llevDebug, "apply, playermove, player speed_left=%f\n", victim->speed_left); */
          }
        goto leave;

      case SPINNER:
        if (victim->direction)
          {
            victim->direction = absdir (victim->direction - trap->stats.sp);
            update_turn_face (victim);
          }
        goto leave;

      case DIRECTOR:
        if (victim->direction && !should_director_abort (trap, victim))
          {
            victim->direction = trap->stats.sp;
            update_turn_face (victim);
          }
        goto leave;

      case BUTTON:
      case PEDESTAL:
        update_button (trap, originator);
        goto leave;

      case ALTAR:
        /* sacrifice victim on trap */
        apply_altar (trap, victim, originator);
        goto leave;

      case THROWN_OBJ:
        if (trap->inv == NULL)
          goto leave;
        /* fallthrough */

      case ARROW:
        /* bad bug: monster throw a object, make a step forwards, step on object ,
         * trigger this here and get hit by own missile - and will be own enemy.
         * Victim then is his own enemy and will start to kill herself (this is
         * removed) but we have not synced victim and his missile. To avoid senseless
         * action, we avoid hits here 
         */
        if ((QUERY_FLAG (victim, FLAG_ALIVE) && trap->speed) && trap->owner != victim)
          hit_with_arrow (trap, victim);
        goto leave;

      case SPELL_EFFECT:
        apply_spell_effect (trap, victim);
        goto leave;

      case TRAPDOOR:
        {
          int max, sound_was_played;
          object *ab, *ab_next;

          if (!trap->value)
            {
              int tot;

              for (ab = trap->above, tot = 0; ab; ab = ab->above)
                if ((ab->move_type && trap->move_on) || ab->move_type == 0)
                  tot += ab->head_ ()->total_weight ();

              if (!(trap->value = (tot > trap->weight) ? 1 : 0))
                goto leave;

              SET_ANIMATION (trap, trap->value);
              update_object (trap, UP_OBJ_FACE);
            }

          for (ab = trap->above, max = 100, sound_was_played = 0; --max && ab; ab = ab_next)
            {
              /* need to set this up, since if we do transfer the object,
               * ab->above would be bogus 
               */
              ab_next = ab->above;

              if ((ab->move_type && trap->move_on) || ab->move_type == 0)
                {
                  if (!sound_was_played)
                    {
                      trap->play_sound (trap->sound ? trap->sound : sound_find ("fall_hole"));
                      sound_was_played = 1;
                    }

                  ab->statusmsg ("You fall into a trapdoor!", NDI_RED);
                  transfer_ob (ab, EXIT_X (trap), EXIT_Y (trap), 0, ab);
                }
            }
          goto leave;
        }

      case CONVERTER:
        if (convert_item (victim, trap) < 0)
          {
            originator->failmsg (format ("The %s seems to be broken!", query_name (trap)));
            archetype::get (shstr_burnout)->insert_at (trap, trap);
          }

        goto leave;

      case TRIGGER_BUTTON:
      case TRIGGER_PEDESTAL:
      case TRIGGER_ALTAR:
        check_trigger (trap, victim);
        goto leave;

      case DEEP_SWAMP:
        walk_on_deep_swamp (trap, victim);
        goto leave;

      case CHECK_INV:
        check_inv (victim, trap);
        goto leave;

      case HOLE:
        move_apply_hole (trap, victim);
        goto leave;

      case EXIT:
        if (victim->type == PLAYER && EXIT_PATH (trap))
          {
            /* Basically, don't show exits leading to random maps the
             * players output.
             */
            if (trap->msg && !EXIT_PATH (trap).starts_with ("/!"))
              victim->statusmsg (trap->msg, NDI_NAVY);

            trap->play_sound (trap->sound);
            victim->enter_exit (trap);
          }
        goto leave;

      case ENCOUNTER:
        /* may be some leftovers on this */
        goto leave;

      case SHOP_MAT:
        apply_shop_mat (trap, victim);
        goto leave;

        /* Drop a certain amount of gold, and have one item identified */
      case IDENTIFY_ALTAR:
        apply_id_altar (victim, trap, originator);
        goto leave;

      case SIGN:
        if (victim->type != PLAYER && trap->stats.food > 0)
          goto leave;           /* monsters musn't apply magic_mouths with counters */

        apply_sign (victim, trap, 1);
        goto leave;

      case CONTAINER:
        apply_container (victim, trap);
        goto leave;

      case RUNE:
      case TRAP:
        if (trap->level && QUERY_FLAG (victim, FLAG_ALIVE))
          spring_trap (trap, victim);
        goto leave;

      default:
        LOG (llevDebug, "name %s, arch %s, type %d with fly/walk on/off not "
             "handled in move_apply()\n", &trap->name, &trap->arch->archname, trap->type);
        goto leave;
    }

leave:
  recursion_depth--;
}

/**
 * Handles reading a regular (ie not containing a spell) book.
 */
static void
apply_book (object *op, object *tmp)
{
  int lev_diff;
  object *skill_ob;

  if (QUERY_FLAG (op, FLAG_BLIND) && !QUERY_FLAG (op, FLAG_WIZ))
    {
      op->failmsg ("You are unable to read while blind!");
      return;
    }

  if (!tmp->msg)
    {
      op->failmsg (format ("You open the %s and find it empty.", &tmp->name));
      return;
    }

  /* need a literacy skill to read stuff! */
  skill_ob = find_skill_by_name (op, tmp->skill);
  if (!skill_ob)
    {
      op->failmsg (format ("You are unable to decipher the strange symbols. H<You lack the %s skill to read this.>", &tmp->skill));
      return;
    }

  lev_diff = tmp->level - (skill_ob->level + 5);
  if (!QUERY_FLAG (op, FLAG_WIZ) && lev_diff > 0)
    {
      op->failmsg (lev_diff  <  2 ? "This book is just barely beyond your comprehension."
                  : lev_diff <  3 ? "This book is slightly beyond your comprehension."
                  : lev_diff <  5 ? "This book is beyond your comprehension."
                  : lev_diff <  8 ? "This book is quite a bit beyond your comprehension."
                  : lev_diff < 15 ? "This book is way beyond your comprehension."
                  :                 "This book is totally beyond your comprehension.");
      return;
    }

  readable_message_type *msgType = get_readable_message_type (tmp);

  if (player *pl = op->contr)
    if (client *ns = pl->ns)
      pl->infobox (MSG_CHANNEL ("book"), format ("T<%s>\n\n%s", (char *)long_desc (tmp, op), &tmp->msg));

  /* gain xp from reading */
  if (!QUERY_FLAG (tmp, FLAG_NO_SKILL_IDENT))
    {                           /* only if not read before */
      int exp_gain = calc_skill_exp (op, tmp, skill_ob);

      if (!QUERY_FLAG (tmp, FLAG_IDENTIFIED))
        {
          /*exp_gain *= 2; because they just identified it too */
          SET_FLAG (tmp, FLAG_IDENTIFIED);

          if (object *pl = tmp->visible_to ())
            esrv_update_item (UPD_FLAGS | UPD_NAME, pl, tmp);
        }

      change_exp (op, exp_gain, skill_ob->skill, 0);
      SET_FLAG (tmp, FLAG_NO_SKILL_IDENT);      /* so no more xp gained from this book */
    }
}

/**
 * Handles the applying of a skill scroll, calling learn_skill straight.
 * op is the person learning the skill, tmp is the skill scroll object
 */
static void
apply_skillscroll (object *op, object *tmp)
{
  switch (learn_skill (op, tmp))
    {
      case 0:
        op->play_sound (sound_find ("generic_fail"));
        op->failmsg (format ("You already possess the knowledge held within the %s.", query_name (tmp)));
        break;

      case 1:
        tmp->decrease ();
        op->play_sound (sound_find ("skill_learn"));
        op->statusmsg (format ("You succeed in learning %s", &tmp->skill));
        break;

      default:
        tmp->decrease ();
        op->play_sound (sound_find ("generic_fail"));
        op->failmsg (format ("You fail to learn the knowledge of the %s.\n", query_name (tmp)));
        break;
    }
}

/**
 * Actually makes op learn spell.
 * Informs player of what happens.
 */
void
do_learn_spell (object *op, object *spell, int special_prayer)
{
  object *tmp;

  if (op->type != PLAYER)
    {
      LOG (llevError, "BUG: do_learn_spell(): not a player\n");
      return;
    }

  /* Upgrade special prayers to normal prayers */
  if ((tmp = check_spell_known (op, spell->name)) != NULL)
    {
      if (special_prayer && !QUERY_FLAG (tmp, FLAG_STARTEQUIP))
        {
          LOG (llevError, "BUG: do_learn_spell(): spell already known, but not marked as startequip\n");
          return;
        }
      return;
    }

  op->contr->play_sound (sound_find ("learn_spell"));

  tmp = spell->clone ();
  insert_ob_in_ob (tmp, op);

  if (special_prayer)
    SET_FLAG (tmp, FLAG_STARTEQUIP);

  esrv_add_spells (op->contr, tmp);
}

/**
 * Erases spell from player's inventory.
 */
void
do_forget_spell (object *op, const char *spell)
{
  object *spob;

  if (op->type != PLAYER)
    {
      LOG (llevError, "BUG: do_forget_spell(): not a player\n");
      return;
    }
  if ((spob = check_spell_known (op, spell)) == NULL)
    {
      LOG (llevError, "BUG: do_forget_spell(): spell not known\n");
      return;
    }

  op->failmsg (format ("You lose knowledge of %s.", spell));
  player_unready_range_ob (op->contr, spob);
  esrv_remove_spell (op->contr, spob);
  spob->destroy ();
}

/**
 * Handles player applying a spellbook.
 * Checks whether player has knowledge of required skill, doesn't already know the spell,
 * stuff like that. Random learning failure too.
 */
static void
apply_spellbook (object *op, object *tmp)
{
  object *skop, *spell, *spell_skill;

  if (QUERY_FLAG (op, FLAG_BLIND) && !QUERY_FLAG (op, FLAG_WIZ))
    {
      op->failmsg ("You are unable to read while blind.");
      return;
    }

  /* artifact_spellbooks have 'slaying' field point to a spell name,
   * instead of having their spell stored in stats.sp.  These are
   * legacy spellbooks
   */
  if (tmp->slaying)
    {
      spell = arch_to_object (find_archetype_by_object_name (tmp->slaying));
      if (!spell)
        {
          op->failmsg (format ("The book's formula for %s is incomplete.", &tmp->slaying));
          return;
        }
      else
        insert_ob_in_ob (spell, tmp);

      tmp->slaying = 0;
    }

  skop = find_skill_by_name (op, tmp->skill);

  /* need a literacy skill to learn spells. Also, having a literacy level
   * lower than the spell will make learning the spell more difficult */
  if (!skop)
    {
      op->failmsg (format ("You can't read! Your attempt fails. H<You lack the %s skill.>", &tmp->skill));
      return;
    }

  spell = tmp->inv;

  if (!spell)
    {
      LOG (llevError, "apply_spellbook: Book %s has no spell in it!\n", &tmp->name);
      op->failmsg ("The spellbook symbols make no sense. This is a bug, please report!");
      return;
    }

  int learn_level = sqrtf (spell->level) * 1.5f;
  if (skop->level < learn_level)
    {
      op->failmsg (format ("You are unable to decipher the strange symbols. H<Your %s level is too low, it must be at least %d.>",
                           &tmp->skill, learn_level));
      return;
    }

  op->statusmsg (format ("The spellbook contains the %s level spell %s.", get_levelnumber (spell->level), &spell->name));

  if (!QUERY_FLAG (tmp, FLAG_IDENTIFIED))
    identify (tmp);

  /* I removed the check for special_prayer_mark here - it didn't make
   * a lot of sense - special prayers are not found in spellbooks, and
   * if the player doesn't know the spell, doesn't make a lot of sense that
   * they would have a special prayer mark.
   */
  if (check_spell_known (op, spell->name))
    {
      op->statusmsg ("You already know that spell. H<It makes no sense to learn spells twice, and would only waste the spellbook.>\n");
      return;
    }

  if (spell->skill)
    {
      spell_skill = find_skill_by_name (op, spell->skill);

      if (!spell_skill)
        {
          op->failmsg (format ("You lack the skill %s to use this spell.", &spell->skill));
          return;
        }

      if (spell_skill->level < spell->level)
        {
          op->failmsg (format ("You need to be level %d in %s to learn this spell.", spell->level, &spell->skill));
          return;
        }
    }

  /* Logic as follows
   *
   *  1- MU spells use Int to learn, Cleric spells use Wisdom
   *
   *  2- The learner's skill level in literacy adjusts the chance to learn
   *     a spell.
   *
   *  3 -Automatically fail to learn if you read while confused
   * 
   * Overall, chances are the same but a player will find having a high 
   * literacy rate very useful!  -b.t. 
   */
  if (QUERY_FLAG (op, FLAG_CONFUSED))
    {
      op->failmsg ("In your confused state you flub the wording of the text!");
      scroll_failure (op, 0 - random_roll (0, spell->level, op, PREFER_LOW), MAX (spell->stats.sp, spell->stats.grace));
    }
  else if (QUERY_FLAG (tmp, FLAG_STARTEQUIP) ||
           (random_roll (0, 100, op, PREFER_LOW) - (5 * skop->level)) < learn_spell[spell->stats.grace ? op->stats.Wis : op->stats.Int])
    {
      op->statusmsg ("You succeed in learning the spell!", NDI_GREEN);
      do_learn_spell (op, spell, 0);

      /* xp gain to literacy for spell learning */
      if (!QUERY_FLAG (tmp, FLAG_STARTEQUIP))
        change_exp (op, calc_skill_exp (op, tmp, skop), skop->skill, 0);
    }
  else
    {
      op->contr->play_sound (sound_find ("fumble_spell"));
      op->failmsg ("You fail to learn the spell. H<Wis (priests) or Int (wizards) governs the chance of learning a prayer or spell.>\n");
    }

  tmp->decrease ();
}

/**
 * Handles applying a spell scroll.
 */
void
apply_scroll (object *op, object *tmp, int dir)
{
  object *skop;

  if (QUERY_FLAG (op, FLAG_BLIND) && !QUERY_FLAG (op, FLAG_WIZ))
    {
      op->failmsg ("You are unable to read while blind.");
      return;
    }

  if (!tmp->inv || tmp->inv->type != SPELL)
    {
      op->failmsg ("The scroll just doesn't make sense! H<...and never will make sense.>");
      return;
    }

  if (op->type == PLAYER)
    {
      /* players need a literacy skill to read stuff! */
      int exp_gain = 0;

      /* hard code literacy - tmp->skill points to where the exp
       * should go for anything killed by the spell.
       */
      skop = find_skill_by_name (op, skill_names[SK_LITERACY]);

      if (!skop)
        {
          op->failmsg (format ("You are unable to decipher the strange symbols. H<You lack the %s skill.>", &skill_names[SK_LITERACY]));
          return;
        }

      if ((exp_gain = calc_skill_exp (op, tmp, skop)))
        change_exp (op, exp_gain, skop->skill, 0);
    }

  if (!QUERY_FLAG (tmp, FLAG_IDENTIFIED))
    identify (tmp);

  op->statusmsg (format ("The scroll of %s turns to dust.", &tmp->inv->name));

  cast_spell (op, tmp, dir, tmp->inv, NULL);
  tmp->decrease ();
}

/**
 * Applies a treasure object - by default, chest.  op
 * is the person doing the applying, tmp is the treasure
 * chest.
 */
static void
apply_treasure (object *op, object *tmp)
{
  /* Nice side effect of this treasure creation method is that the treasure
   * for the chest is done when the chest is created, and put into the chest
   * inventory. So that when the chest burns up, the items still exist. Also
   * prevents people from moving chests to more difficult maps to get better
   * treasure
   */
  object *treas = tmp->inv;

  if (!treas)
    {
      op->statusmsg ("The chest was empty.");
      tmp->decrease ();
      return;
    }

  while (tmp->inv)
    {
      treas = tmp->inv;
      treas->remove ();

      treas->x = op->x;
      treas->y = op->y;
      treas = insert_ob_in_map (treas, op->map, op, INS_BELOW_ORIGINATOR);

      if (treas && (treas->type == RUNE || treas->type == TRAP) && treas->level && QUERY_FLAG (op, FLAG_ALIVE))
        spring_trap (treas, op);

      /* If either player or container was destroyed, no need to do
       * further processing. I think this should be enclused with
       * spring trap above, as I don't think there is otherwise
       * any way for the treasure chest or player to get killed.
       */
      if (op->destroyed () || tmp->destroyed ())
        break;
    }

  if (!tmp->destroyed () && !tmp->inv)
    tmp->decrease (true);
}

/**
 * op eats food.
 * If player, takes care of messages and dragon special food.
 */
static void
apply_food (object *op, object *tmp)
{
  int capacity_remaining;

  if (op->type != PLAYER)
    op->stats.hp = op->stats.maxhp;
  else
    {
      /* check if this is a dragon (player), eating some flesh */
      if (tmp->type == FLESH && is_dragon_pl (op) && dragon_eat_flesh (op, tmp))
        ;
      else
        {
          /* usual case - no dragon meal: */
          if (op->stats.food + tmp->stats.food > 999)
            {
              if (tmp->type == FOOD || tmp->type == FLESH)
                op->failmsg ("You feel full, but what a waste of food!");
              else
                op->statusmsg ("Most of the drink goes down your face not your throat!");
            }

          tmp->play_sound (
             tmp->sound
                ? tmp->sound
                : tmp->type == DRINK
                     ? sound_find ("eat_drink")
                     : sound_find ("eat_food")
          );

          if (!QUERY_FLAG (tmp, FLAG_CURSED))
            {
              const char *buf;

              if (!is_dragon_pl (op))
                {
                  /* eating message for normal players */
                  if (tmp->type == DRINK)
                    buf = format ("Ahhh...that %s tasted good.", &tmp->name);
                  else
                    buf = format ("The %s tasted %s", &tmp->name, tmp->type == FLESH ? "terrible!" : "good.");
                }
              else
                /* eating message for dragon players */
                buf = format ("The %s tasted terrible!", &tmp->name);

              op->statusmsg (buf);

              capacity_remaining = 999 - op->stats.food;
              op->stats.food += tmp->stats.food;
              if (capacity_remaining < tmp->stats.food)
                op->stats.hp += capacity_remaining / 50;
              else
                op->stats.hp += tmp->stats.food / 50;

              if (op->stats.hp > op->stats.maxhp)
                op->stats.hp = op->stats.maxhp;
              if (op->stats.food > 999)
                op->stats.food = 999;
            }

          /* special food hack -b.t. */
          if (tmp->title || QUERY_FLAG (tmp, FLAG_CURSED))
            eat_special_food (op, tmp);
        }
    }

  handle_apply_yield (tmp);
  tmp->decrease ();
}

/**
 * A dragon is eating some flesh. If the flesh contains resistances,
 * there is a chance for the dragon's skin to get improved.
 *
 * attributes:
 *     object *op        the object (dragon player) eating the flesh
 *     object *meal      the flesh item, getting chewed in dragon's mouth
 * return:
 *     int               1 if eating successful, 0 if it doesn't work
 */
int
dragon_eat_flesh (object *op, object *meal)
{
  object *skin = NULL;          /* pointer to dragon skin force */
  object *abil = NULL;          /* pointer to dragon ability force */
  object *tmp = NULL;           /* tmp. object */

  double chance;                /* improvement-chance of one resistance type */
  double totalchance = 1;       /* total chance of gaining one resistance */
  double bonus = 0;             /* level bonus (improvement is easier at lowlevel) */
  double mbonus = 0;            /* monster bonus */
  int atnr_winner[NROFATTACKS]; /* winning candidates for resistance improvement */
  int winners = 0;              /* number of winners */
  int i;                        /* index */

  /* let's make sure and doublecheck the parameters */
  if (meal->type != FLESH || !is_dragon_pl (op))
    return 0;

  /* now grab the 'dragon_skin'- and 'dragon_ability'-forces
     from the player's inventory */
  for (tmp = op->inv; tmp; tmp = tmp->below)
    if (tmp->type == FORCE)
      if (tmp->arch->archname == shstr_dragon_skin_force)
        skin = tmp;
      else if (tmp->arch->archname == shstr_dragon_ability_force)
        abil = tmp;

  /* if either skin or ability are missing, this is an old player
     which is not to be considered a dragon -> bail out */
  if (skin == NULL || abil == NULL)
    return 0;

  /* now start by filling stomache and health, according to food-value */
  if ((999 - op->stats.food) < meal->stats.food)
    op->stats.hp += (999 - op->stats.food) / 50;
  else
    op->stats.hp += meal->stats.food / 50;

  if (op->stats.hp > op->stats.maxhp)
    op->stats.hp = op->stats.maxhp;

  op->stats.food = MIN (999, op->stats.food + meal->stats.food);

  /*LOG(llevDebug, "-> player: %d, flesh: %d\n", op->level, meal->level); */

  /* on to the interesting part: chances for adding resistance */
  for (i = 0; i < NROFATTACKS; i++)
    {
      if (meal->resist[i] > 0 && atnr_is_dragon_enabled (i))
        {
          /* got positive resistance, now calculate improvement chance (0-100) */

          /* this bonus makes resistance increase easier at lower levels */
          bonus = (settings.max_level - op->level) * 30. / ((double) settings.max_level);
          if (i == abil->stats.exp)
            bonus += 5;         /* additional bonus for resistance of ability-focus */

          /* monster bonus increases with level, because high-level
             flesh is too rare */
          mbonus = op->level * 20. / ((double) settings.max_level);

          chance = (((double) MIN (op->level + bonus, meal->level + bonus + mbonus)) * 100. /
                    ((double) settings.max_level)) - skin->resist[i];

          if (chance >= 0.)
            chance += 1.;
          else
            chance = (chance < -12) ? 0. : 1. / pow (2., -chance);

          /* chance is proportional to amount of resistance (max. 50) */
          chance *= ((double) (MIN (meal->resist[i], 50))) / 50.;

          /* doubled chance for resistance of ability-focus */
          if (i == abil->stats.exp)
            chance = MIN (100., chance * 2.);

          /* now make the throw and save all winners (Don't insert luck bonus here!) */
          if (rndm (10000) < (unsigned int) (chance * 100))
            {
              atnr_winner[winners] = i;
              winners++;
            }

          if (chance >= 0.01)
            totalchance *= 1 - chance / 100;

          /*LOG(llevDebug, "   %s: bonus %.1f, chance %.1f\n", attacks[i], bonus, chance); */
        }
    }

  /* inverse totalchance as until now we have the failure-chance   */
  totalchance = 100 - totalchance * 100;

  /* print message according to totalchance */
  const char *buf;
  if (totalchance > 50.)
    buf = format ("Hmm! The %s tasted delicious!", &meal->name);
  else if (totalchance > 10.)
    buf = format ("The %s tasted very good.", &meal->name);
  else if (totalchance > 1.)
    buf = format ("The %s tasted good.", &meal->name);
  else if (totalchance > 0.1)
    buf = format ("The %s tasted bland.", &meal->name);
  else if (totalchance >= 0.01)
    buf = format ("The %s had a boring taste.", &meal->name);
  else if (meal->last_eat > 0 && atnr_is_dragon_enabled (meal->last_eat))
    buf = format ("The %s tasted strange.", &meal->name);
  else
    buf = format ("The %s had no taste.", &meal->name);

  op->statusmsg (buf);

  /* now choose a winner if we have any */
  i = -1;
  if (winners > 0)
    i = atnr_winner [rndm (winners)];

  if (i >= 0 && i < NROFATTACKS && skin->resist[i] < 95)
    {
      /* resistance increased! */
      skin->resist[i]++;
      op->update_stats ();

      op->statusmsg (format ("Your skin is now more resistant to %s!", change_resist_msg[i]));
    }

  /* if this flesh contains a new ability focus, we mark it
     into the ability_force and it will take effect on next level */
  if (meal->last_eat > 0 && atnr_is_dragon_enabled (meal->last_eat) && meal->last_eat != abil->last_eat)
    {
      abil->last_eat = meal->last_eat;  /* write: last_eat <new attnr focus> */

      if (meal->last_eat != abil->stats.exp)
        op->statusmsg (format (
          "Your metabolism prepares to focus on %s!\n"
          "The change will happen at level %d.",
          change_resist_msg[meal->last_eat],
          abil->level + 1
        ));
      else
        {
          op->statusmsg (format ("Your metabolism will continue to focus on %s.", change_resist_msg[meal->last_eat]));
          abil->last_eat = 0;
        }
    }

  return 1;
}

/**
 * Handles applying an improve armor scroll.
 * Does some sanity checks, then calls improve_armour.
 */
static void
apply_armour_improver (object *op, object *tmp)
{
  object *armor;

  if (!QUERY_FLAG (op, FLAG_WIZCAST) && (get_map_flags (op->map, 0, op->x, op->y, 0, 0) & P_NO_MAGIC))
    {
      op->failmsg ("Something blocks the magic of the scroll. H<This area prevents magic effects.>");
      return;
    }

  armor = find_marked_object (op);

  if (!armor)
    {
      op->failmsg ("You need to mark an armor object. Use the right mouse button popup or the mark command to do this.");
      return;
    }

  if (armor->type != ARMOUR
      && armor->type != CLOAK
      && armor->type != BOOTS && armor->type != GLOVES && armor->type != BRACERS && armor->type != SHIELD && armor->type != HELMET)
    {
      op->failmsg ("Your marked item is not armour!\n");
      return;
    }

  op->statusmsg ("Applying armour enchantment.");
  improve_armour (op, tmp, armor);
}

void
apply_poison (object *op, object *tmp)
{
  // need to do it now when it is still on the map
  handle_apply_yield (tmp);

  object *poison = tmp->split (1);

  if (op->type == PLAYER)
    {
      op->contr->play_sound (sound_find ("drink_poison"));
      op->failmsg ("Yech! That tasted poisonous!");
      op->contr->killer = poison;
    }

  if (poison->stats.hp > 0)
    {
      LOG (llevDebug, "Trying to poison player/monster for %d hp\n", poison->stats.hp);
      hit_player (op, poison->stats.hp, tmp, AT_POISON, 1);
    }

  op->stats.food -= op->stats.food / 4;
  poison->destroy ();
}

/**
 * This function return true if the exit is not a 2 ways one or it is 2 ways, valid exit.
 * A valid 2 way exit means:
 *   -You can come back (there is another exit at the other side)
 *   -You are
 *         ° the owner of the exit
 *         ° or in the same party as the owner
 *
 * Note: a owner in a 2 way exit is saved as the owner's name
 * in the field exit->name cause the field exit->owner doesn't
 * survive in the swapping (in fact the whole exit doesn't survive).
 */
int
is_legal_2ways_exit (object *op, object *exit)
{
  if (exit->stats.exp != 1)
    return 1;                   /*This is not a 2 way, so it is legal */

#if 0 //TODO
  if (!has_been_loaded (EXIT_PATH (exit)) && exit->race)
    return 0;                   /* This is a reset town portal */
#endif

  LOG (llevError | logBacktrace, "sync map load due to %s\n", exit->debug_desc ());

  maptile *exitmap = maptile::find_sync (EXIT_PATH (exit), exit->map);

  if (exitmap)
    {
      exitmap->load_sync ();

      object *tmp = exitmap->at (EXIT_X (exit), EXIT_Y (exit)).bot;

      if (!tmp)
        return 0;

      for (; tmp; tmp = tmp->above)
        {
          if (tmp->type != EXIT)
            continue;           /*Not an exit */

          if (!EXIT_PATH (tmp))
            continue;           /*Not a valid exit */

          if ((EXIT_X (tmp) != exit->x) || (EXIT_Y (tmp) != exit->y))
            continue;           /*Not in the same place */

          if (exit->map->path != EXIT_PATH (tmp))
            continue;           /*Not in the same map */

          /* From here we have found the exit is valid. However we do
           * here the check of the exit owner. It is important for the
           * town portals to prevent strangers from visiting your appartments
           */
          if (!exit->race)
            return 1;           /*No owner, free for all! */

          object *exit_owner = 0;

          for_all_players (pp)
            {
              if (!pp->ob)
                continue;

              if (pp->ob->name != exit->race)
                continue;

              exit_owner = pp->ob;      /*We found a player which correspond to the player name */
              break;
            }

          if (!exit_owner)
            return 0;           /* No more owner */

          if (exit_owner->contr == op->contr)
            return 1;           /*It is your exit */

          if (exit_owner &&     /*There is a owner */
              (op->contr) &&    /*A player tries to pass */
              ((exit_owner->contr->party == NULL) ||    /*No pass if controller has no party */
               (exit_owner->contr->party != op->contr->party))) /* Or not the same as op */
            return 0;

          return 1;
        }
    }

  return 0;
}

/**
 * This function will try to apply a lighter and in case no lighter
 * is specified it will try to find a lighter in the players inventory,
 * and inform him about this requirement.
 *
 * who    - the player
 * op     - the item we want to light
 * ligher - the lighter or 0 if a lighter has yet to be found
 */
object *
auto_apply_lighter (object *who, object *op, object *lighter)
{
  if (lighter == 0)
    {
      for (object *tmp = who->inv; tmp; tmp = tmp->below)
        {
          if (tmp->type == LIGHTER)
            {
              lighter = tmp;
              break;
            }
        }

      if (!lighter)
        {
          who->failmsg (format (
            "You can't light up the %s with your bare hands! "
            "H<You need a lighter in your inventory, for example a flint and steel.>",
            &op->name));
          return 0;
        }
    }

  // last_eat == 0 means the lighter is not being used up!
  if (lighter->last_eat && lighter->stats.food)
    {
      /* lighter gets used up */
      lighter = lighter->split ();
      lighter->stats.food--;
      who->insert (lighter);
    }
  else if (lighter->last_eat)
    {
      /* no charges left in lighter */
      who->failmsg (format (
        "You attempt to light the %s with a used up %s.",
        &op->name, &lighter->name));
      return 0;
    }

  return lighter;
}

/**
 * Designed primarily to light torches/lanterns/etc.
 * Also burns up burnable material too. First object in the inventory is
 * the selected object to "burn". -b.t.
 */
void
apply_lighter (object *who, object *lighter)
{
  object *item;
  int is_player_env = 0;

  item = find_marked_object (who);
  if (item)
    {
      if (!auto_apply_lighter (who, item, lighter))
        return;

      /* Perhaps we should split what we are trying to light on fire?
       * I can't see many times when you would want to light multiple
       * objects at once.
       */

      save_throw_object (item, AT_FIRE, who);

      if (item->destroyed ()
          || ((item->type == LAMP || item->type == TORCH)
              && item->glow_radius > 0))
        who->statusmsg (format (
          "You light the %s with the %s.",
          &item->name, &lighter->name));
      else
        who->failmsg (format (
          "You attempt to light the %s with the %s and fail.",
          &item->name, &lighter->name));
    }
  else
    who->failmsg ("You need to mark a lightable object.");
}

/**
 * This function generates a cursed effect for cursed lamps and torches.
 */
void player_apply_lamp_cursed_effect (object *who, object *op)
{
  if (op->level)
    {
      who->failmsg (format (
        "The %s was cursed, it explodes in a big fireball!",
        &op->name));
      create_exploding_ball_at (who, op->level);
    }
  else
    {
      who->failmsg (format (
        "The %s was cursed, it crumbles to dust, at least it didn't explode.!",
        &op->name));
    }

  op->destroy ();
}

/**
 * Apply for players and lamps
 *
 * who - the player
 * op  - the lamp
 */
void player_apply_lamp (object *who, object *op)
{
  bool switch_on = op->glow_radius ? false : true;

  if (switch_on)
    {
      object *lighter = 0;

      if (op->flag [FLAG_IS_LIGHTABLE]
          && !(lighter = auto_apply_lighter (who, op, 0)))
        return;

      if (op->stats.food < 1)
        {
          if (op->type == LAMP)
            who->failmsg (format (
              "The %s is out of fuel! "
              "H<Lamps and similar items need fuel. They cannot be refilled.>",
              &op->name));
          else
            who->failmsg (format (
              "The %s is burnt out! "
              "H<Torches and similar items burn out and become worthless.>",
              &op->name));
          return;
        }

      if (op->flag [FLAG_CURSED])
        {
          player_apply_lamp_cursed_effect (who, op);
          return;
        }

      if (lighter)
        who->statusmsg (format (
          "You light up the %s with the %s.", &op->name, &lighter->name));
      else
        who->statusmsg (format ("You light up the %s.", &op->name));
    }
  else
    {
      if (op->flag [FLAG_CURSED])
        {
          player_apply_lamp_cursed_effect (who, op);
          return;
        }

      if (op->type == TORCH)
        {
          if (!op->flag [FLAG_IS_LIGHTABLE])
            {
              who->statusmsg (format (
                  "You put out the %s. "
                  "H<The %s can't be used anymore, as it can't be lighted up again.>",
                  &op->name, &op->name));
            }
          else
            who->statusmsg (format (
                "You put out the %s."
                "H<Torches wear out if you put them out.>",
                &op->name));
        }
      else
        who->statusmsg (format ("You turn off the %s.", &op->name));
    }

  apply_lamp (op, switch_on);
}

void get_animation_from_arch (object *op, arch_ptr a)
{
  op->animation_id            = a->animation_id;
  op->flag [FLAG_IS_TURNABLE] = a->flag [FLAG_IS_TURNABLE];
  op->flag [FLAG_ANIMATE]     = a->flag [FLAG_ANIMATE];
  op->anim_speed              = a->anim_speed;
  op->last_anim               = 0;
  op->state                   = 0;
  op->face                    = a->face;

  if (NUM_ANIMATIONS(op) > 1)
    {
      SET_ANIMATION(op, 0);
      animate_object (op, op->direction);
    }
  else
    update_object (op, UP_OBJ_FACE);
}

/**
 * Apply for LAMPs and TORCHes.
 *
 * op        - the lamp
 * switch_on - a flag which says whether the lamp should be switched on or off
 */
void apply_lamp (object *op, bool switch_on)
{
  op->set_glow_radius (switch_on ? op->range       : 0);
  op->set_speed       (switch_on ? op->arch->speed : 0);

  // torches wear out if you put them out
  if (op->type == TORCH && !switch_on)
    {
      if (op->flag [FLAG_IS_LIGHTABLE])
        {
          op->stats.food -= (double) op->arch->stats.food / 15;
          if (op->stats.food < 0)
            op->stats.food = 0;
        }
      else
        op->stats.food = 0;
    }

  // lamps and torched get worthless when used up
  if (op->stats.food <= 0)
    op->value = 0;

  // FIXME: This is a hack to make the more sane torches and lamps
  //        still animated ;-/
  if (op->other_arch)
    get_animation_from_arch (op, switch_on ? op->other_arch : op->arch);

  if (object *pl = op->visible_to ())
    esrv_update_item (UPD_ANIM | UPD_FACE | UPD_NAME, pl, op);
}

/**
 * Main apply handler.
 *
 * Checks for unpaid items before applying.
 *
 * Return value:
 *   0: player or monster can't apply objects of that type
 *   1: has been applied, or there was an error applying the object
 *   2: objects of that type can't be applied if not in inventory
 *
 * who is the object that is causing object to be applied, op is the object
 * being applied.
 *
 * aflag is special (always apply/unapply) flags.  Nothing is done with
 * them in this function - they are passed to apply_special
 */
int
manual_apply (object *who, object *op, int aflag)
{
  op = op->head_ ();

  if (QUERY_FLAG (op, FLAG_UNPAID) && !QUERY_FLAG (op, FLAG_APPLIED))
    {
      if (who->type == PLAYER)
        {
          examine (who, op);
          //who->failmsg ("You should pay for it first! H<You cannot use items marked as unpaid.>");//TODO remove
          return 1;
        }
      else
        return 0;             /* monsters just skip unpaid items */
    }

  if (INVOKE_OBJECT (APPLY, op, ARG_OBJECT (who)))
    return RESULT_INT (0);

  switch (op->type)
    {
      case CF_HANDLE:
        who->play_sound (sound_find ("turn_handle"));
        who->statusmsg ("You turn the handle.");
        op->value = op->value ? 0 : 1;
        SET_ANIMATION (op, op->value);
        update_object (op, UP_OBJ_FACE);
        push_button (op, who);
        return 1;

      case TRIGGER:
        if (check_trigger (op, who))
          {
            who->statusmsg ("You turn the handle.");
            who->play_sound (sound_find ("turn_handle"));
          }
        else
          who->failmsg ("The handle doesn't move.");

        return 1;

      case EXIT:
        if (who->type != PLAYER)
          return 0;

        if (!EXIT_PATH (op) || !is_legal_2ways_exit (who, op))
          who->failmsg (format ("The %s is closed.", query_name (op)));
        else
          {
            /* Don't display messages for random maps. */
            if (op->msg && !EXIT_PATH (op).starts_with ("/!"))
              who->statusmsg (op->msg, NDI_NAVY);

            who->enter_exit (op);
          }

        return 1;

      case INSCRIBABLE:
        who->statusmsg (op->msg);
        // maybe show a spell menu to chose from or something like that
        return 1;

      case SIGN:
        apply_sign (who, op, 0);
        return 1;

      case BOOK:
        if (who->type == PLAYER)
          {
            apply_book (who, op);
            return 1;
          }
        else
          return 0;

      case SKILLSCROLL:
        if (who->type == PLAYER)
          {
            apply_skillscroll (who, op);
            return 1;
          }
        else
          return 0;

      case SPELLBOOK:
        if (who->type == PLAYER)
          {
            apply_spellbook (who, op);
            return 1;
          }
        else
          return 0;

      case SCROLL:
        apply_scroll (who, op, 0);
        return 1;

      case POTION:
        apply_potion (who, op);
        return 1;

        /* Eneq(@csd.uu.se): Handle apply on containers. */
        //TODO: remove, as it is unsed?
      case CLOSE_CON:
        apply_container (who, op->env);
        return 1;

      case CONTAINER:
        apply_container (who, op);
        return 1;

      case TREASURE:
        if (who->type == PLAYER)
          {
            apply_treasure (who, op);
            return 1;
          }
        else
          return 0;

      case LAMP:
      case TORCH:
        player_apply_lamp (who, op);
        return 1;

      case WEAPON:
      case ARMOUR:
      case BOOTS:
      case GLOVES:
      case AMULET:
      case GIRDLE:
      case BRACERS:
      case SHIELD:
      case HELMET:
      case RING:
      case CLOAK:
      case WAND:
      case ROD:
      case HORN:
      case SKILL:
      case BOW:
      case BUILDER:
      case SKILL_TOOL:
        if (op->env != who)
          return 2;             /* not in inventory */

        apply_special (who, op, aflag);
        return 1;

      case DRINK:
      case FOOD:
      case FLESH:
        apply_food (who, op);
        return 1;

      case POISON:
        apply_poison (who, op);
        return 1;

      case SAVEBED:
        return 1;

      case ARMOUR_IMPROVER:
        if (who->type == PLAYER)
          {
            apply_armour_improver (who, op);
            return 1;
          }
        else
          return 0;

      case WEAPON_IMPROVER:
        check_improve_weapon (who, op);
        return 1;

      case CLOCK:
        if (who->type == PLAYER)
          {
            char buf[MAX_BUF];
            timeofday_t tod;

            get_tod (&tod);
            who->play_sound (sound_find ("sound_clock"));
            who->statusmsg (format (
              "It is %d minute%s past %d o'clock %s",
              tod.minute + 1, ((tod.minute + 1 < 2) ? "" : "s"),
              ((tod.hour % 14 == 0) ? 14 : ((tod.hour) % 14)), ((tod.hour >= 14) ? "pm" : "am")
            ));
            return 1;
          }
        else
          return 0;

      case MENU:
        if (who->type == PLAYER)
          {
            shop_listing (op, who);
            return 1;
          }
        else
          return 0;

      case POWER_CRYSTAL:
        apply_power_crystal (who, op);  /*  see egoitem.c */
        return 1;

      case LIGHTER:            /* for lighting torches/lanterns/etc */
        if (who->type == PLAYER)
          {
            apply_lighter (who, op);
            return 1;
          }
        else
          return 0;

      case ITEM_TRANSFORMER:
        apply_item_transformer (who, op);
        return 1;

      default:
        return 0;
    }
}

/* quiet suppresses the "don't know how to apply" and "you must get it first"
 * messages as needed by player_apply_below().  But there can still be
 * "but you are floating high above the ground" messages.
 *
 * Same return value as apply() function.
 */
int
player_apply (object *pl, object *op, int aflag, int quiet)
{
  if (!op->env && (pl->move_type & MOVE_FLYING))
    {
      /* player is flying and applying object not in inventory */
      if (!QUERY_FLAG (pl, FLAG_WIZ) && !(op->move_type & MOVE_FLYING))
        {
          pl->failmsg ("But you are floating high above the ground! "
                       "H<You have to stop levitating first, if you can, either by using your levitation skill, "
                       "or waiting till the levitation effect wears off.>");
          return 0;
        }
    }

  pl->contr->last_used = op;

  int tmp = manual_apply (pl, op, aflag);

  if (!quiet)
    {
      if (tmp == 0)
        pl->statusmsg (format ("I don't know how to apply the %s.", query_name (op)));
      else if (tmp == 2)
        pl->failmsg ("You must get it first!\n");
    }

  return tmp;
}

/**
 * player_apply_below attempts to apply the object 'below' the player.
 * If the player has an open container, we use that for below, otherwise
 * we use the ground.
 */
void
player_apply_below (object *pl)
{
  int floors = 0;

  /* If using a container, set the starting item to be the top
   * item in the container.  Otherwise, use the map.
   * This is perhaps more complicated.  However, I want to make sure that
   * we don't use a corrupt pointer for the next object, so we get the
   * next object in the stack before applying.  This is can only be a
   * problem if player_apply() has a bug in that it uses the object but does
   * not return a proper value.
   */
  for (object *next, *tmp = pl->container ? pl->container->inv : pl->below; tmp; tmp = next)
    {
      next = tmp->below;

      if (QUERY_FLAG (tmp, FLAG_IS_FLOOR))
        floors++;
      else if (floors > 0)
        return;                 /* process only floor objects after first floor object */

      /* If it is visible, player can apply it.  If it is applied by
       * person moving on it, also activate.  Added code to make it
       * so that at least one of players movement types be that which
       * the item needs.
       */
      if (!tmp->invisible || (tmp->move_on & pl->move_type))
        if (player_apply (pl, tmp, 0, 1) == 1)
          return;

      if (floors >= 2)
        return;                 /* process at most two floor objects */
    }
}

/**
 * Unapplies specified item.
 * No check done on cursed/damned.
 * Break this out of apply_special - this is just done
 * to keep the size of apply_special to a more managable size.
 */
static int
unapply_special (object *who, object *op, int aflags)
{
  if (INVOKE_OBJECT (BE_UNREADY, op, ARG_OBJECT (who), ARG_INT (aflags))
      || INVOKE_OBJECT (UNREADY, who, ARG_OBJECT (op), ARG_INT (aflags)))
    return RESULT_INT (0);

  CLEAR_FLAG (op, FLAG_APPLIED);

  switch (op->type)
    {
      case SKILL_TOOL:
        // unapplying a skill tool should also unapply the skill it governs
        // but this is hard, as it shouldn't do so when the skill can
        // be used for other reasons
        for (object *tmp = who->inv; tmp; tmp = tmp->below)
          if (tmp->skill == op->skill
              && tmp->type == SKILL
              && tmp->flag [FLAG_APPLIED]
              && !tmp->flag [FLAG_CAN_USE_SKILL])
            unapply_special (who, tmp, 0);

        change_abil (who, op);
        break;

      case WEAPON:
        if (player *pl = who->contr)
          if (op == pl->combat_ob)
            {
              pl->combat_ob = 0;
              who->change_weapon (pl->ranged_ob);
            }

        who->statusmsg (format ("You unwield %s.", query_name (op)));

        change_abil (who, op);
        CLEAR_FLAG (who, FLAG_READY_WEAPON);
        break;

      case SKILL:
        if (who->contr)
          {
            if (IS_COMBAT_SKILL (op->subtype))
              who->change_weapon (who->contr->combat_ob = 0);
            else if (IS_RANGED_SKILL (op->subtype))
              who->change_weapon (who->contr->ranged_ob = 0);

            if (op->invisible)
              who->statusmsg (format ("You can no longer use the skill: %s.", &op->skill));
            else
              who->statusmsg (format ("You stop using the %s.", query_name (op)));
          }

        change_abil (who, op);
        CLEAR_FLAG (who, FLAG_READY_SKILL);
        break;

      case ARMOUR:
      case HELMET:
      case SHIELD:
      case RING:
      case BOOTS:
      case GLOVES:
      case AMULET:
      case GIRDLE:
      case BRACERS:
      case CLOAK:
        who->statusmsg (format ("You unwear %s.", query_name (op)));
        change_abil (who, op);
        break;

      case BOW:
      case WAND:
      case ROD:
      case HORN:
        if (player *pl = who->contr)
          {
            if (op == pl->ranged_ob)
              {
                pl->ranged_ob = 0;
                who->change_weapon (pl->combat_ob);
              }

            who->statusmsg (format ("You unready %s.", query_name (op)));
          }
        else
          {
            who->change_skill (0);

            if (op->type == BOW)
              CLEAR_FLAG (who, FLAG_READY_BOW);
            else
              CLEAR_FLAG (who, FLAG_READY_RANGE);
          }

        break;

      case BUILDER:
        if (who->contr)
          who->statusmsg (format ("You unready %s.", query_name (op)));
        break;

      default:
        who->statusmsg (format ("You unapply %s.", query_name (op)));
        break;
    }

  if (aflags & AP_NO_MERGE || !merge_ob (op, 0))
    if (object *pl = op->visible_to ())
      esrv_send_item (pl, op);

  who->update_stats ();

  return 0;
}

/**
 * Returns the object that is using location 'loc'.
 * Note that 'start' is the first object to start examing - we
 * then go through the below of this.  In this way, you can do
 * something like:
 * tmp = get_next_item_from_body_location(who->inv, 1);
 * if (tmp) tmp1 = get_next_item_from_body_location(tmp->below, 1);
 * to find the second object that may use this location, etc.
 * Returns NULL if no match is found.
 * loc is the index into the array we are looking for a match.
 * don't return invisible objects unless they are skill objects
 * invisible other objects that use
 * up body locations can be used as restrictions.
 */
static object *
get_next_item_from_body_location (int loc, object *start)
{
  for (object *tmp = start; tmp; tmp = tmp->below)
    if (tmp->flag [FLAG_APPLIED]
        && tmp->slot[loc].info
        && (!tmp->invisible || tmp->type == SKILL))
      return tmp;

  return 0;
}

/**
 * 'op' wants to apply an object, but can't because of other equipment.
 * This should only be called when it is known
 * that there are objects to unapply.  This makes pretty heavy
 * use of get_item_from_body_location.  It makes no intelligent choice
 * on objects - rather, the first that is matched is used.
 * Returns 0 on success, returns 1 if there is some problem.
 * if aflags is AP_PRINT, we instead print out waht to unapply
 * instead of doing it.  This is a lot less code than having
 * another function that does just that.
 */

#define CANNOT_REMOVE_CURSED \
  "H<You cannot remove cursed or damned items, you first have to remove the curse. " \
  "Praying over an altar, scrolls of remove curse/damnation, " \
  "priests or even other players might help.>"

int
unapply_for_ob (object *who, object *op, int aflags)
{
  if (op->is_range ())
    for (object *tmp = who->inv; tmp; tmp = tmp->below)
      if (QUERY_FLAG (tmp, FLAG_APPLIED) && tmp->is_range ())
        if ((aflags & AP_IGNORE_CURSE) || (aflags & AP_PRINT) || (!QUERY_FLAG (tmp, FLAG_CURSED) && !QUERY_FLAG (tmp, FLAG_DAMNED)))
          {
            if (aflags & AP_PRINT)
              who->failmsg (query_name (tmp));
            else
              unapply_special (who, tmp, aflags);
          }
        else
          {
            /* In this case, we want to try and remove a cursed item.
             * While we know it won't work, we want unapply_special to
             * at least generate the message.
             */
            who->failmsg (format ("No matter how hard you try, you just can't remove the %s." CANNOT_REMOVE_CURSED, query_name (tmp)));
            return 1;
          }

  for (int i = 0; i < NUM_BODY_LOCATIONS; i++)
    {
      /* this used up a slot that we need to free */
      if (op->slot[i].info)
        {
          object *last = who->inv;

          /* We do a while loop - may need to remove several items in order
           * to free up enough slots.
           */
          while ((who->slot[i].used + op->slot[i].info) < 0)
            {
              object *tmp = get_next_item_from_body_location (i, last);

              if (!tmp)
                {
#if 0
                  /* Not a bug - we'll get this if the player has cursed items
                   * equipped.
                   */
                  LOG (llevError, "Can't find object using location %d (%s) on %s\n", i, body_locations[i].save_name, who->name);
#endif
                  return 1;
                }

              /* If we are just printing, we don't care about cursed status */
              if ((aflags & AP_IGNORE_CURSE) || (aflags & AP_PRINT) || (!(QUERY_FLAG (tmp, FLAG_CURSED) || QUERY_FLAG (tmp, FLAG_DAMNED))))
                {
                  if (aflags & AP_PRINT)
                    who->failmsg (query_name (tmp));
                  else
                    unapply_special (who, tmp, aflags);
                }
              else
                {
                  /* Cursed item that we can't unequip - tell the player.
                   * Note this could be annoying if this is just one of a few,
                   * so it may not be critical (eg, putting on a ring and you have
                   * one cursed ring.)
                   */
                  who->failmsg (format ("The %s just won't come off." CANNOT_REMOVE_CURSED, query_name (tmp)));
                }

              last = tmp->below;
            }
          /* if we got here, this slot is freed up - otherwise, if it wasn't freed up, the
           * return in the !tmp would have kicked in.
           */
        }                       /* if op is using this body location */
    }                           /* for body lcoations */

  return 0;
}

/**
 * Checks to see if 'who' can apply object 'op'.
 * Returns 0 if apply can be done without anything special.
 * Otherwise returns a bitmask - potentially several of these may be
 * set, but largely depends on circumstance - in the future, processing
 * may be pruned once we know some status (eg, once CAN_APPLY_NEVER
 * is set, do we really care what the other flags may be?)
 *
 * See include/define.h for detailed description of the meaning of
 * these return values.
 */
int
can_apply_object (object *who, object *op)
{
  if (INVOKE_OBJECT (CAN_BE_APPLIED, op, ARG_OBJECT (who)) || INVOKE_OBJECT (CAN_APPLY, who, ARG_OBJECT (op)))
    return RESULT_INT (0);

  int retval = 0;
  object *tmp = 0, *ws = 0;

  for (int i = 0; i < NUM_BODY_LOCATIONS; i++)
    {
      if (op->slot[i].info)
        {
          /* Item uses more slots than we have */
          if (who->slot[i].info + op->slot [i].info < 0)
            {
              /* Could return now for efficiency - rest of info below isn't
               * really needed.
               */
              retval |= CAN_APPLY_NEVER;
            }
          else if (who->slot[i].used + op->slot[i].info < 0)
            {
              /* in this case, equipping this would use more free spots than
               * we have.
               */

              /* if we have an applied weapon/shield, and unapply it would free
               * enough slots to equip the new item, then just set "can
               * apply unapply". We don't care about the logic below - if you have a
               * shield equipped and try to equip another shield, there is only
               * one choice.  However, the check for the number of body locations 
               * does take into the account cases where what is being applied
               * may be two handed for example.
               */
              if (ws)
                if ((who->slot[i].used - ws->slot[i].info + op->slot[i].info) >= 0)
                  {
                    retval |= CAN_APPLY_UNAPPLY;
                    continue;
                  }

              object *tmp1 = get_next_item_from_body_location (i, who->inv);
              if (!tmp1)
                {
#if 0
                  /* This is sort of an error, but happens a lot when old players
                   * join in with more stuff equipped than they are now allowed.
                   */
                  LOG (llevError, "Can't find object using location %d on %s\n", i, who->name);
#endif
                  retval |= CAN_APPLY_NEVER;
                }
              else
                {
                  /* need to unapply something.  However, if this something
                   * is different than we had found before, it means they need
                   * to apply multiple objects
                   */
                  retval |= CAN_APPLY_UNAPPLY;

                  if (!tmp)
                    tmp = tmp1;
                  else if (tmp != tmp1)
                    retval |= CAN_APPLY_UNAPPLY_MULT;

                  /* This object isn't using up all the slots, so there must
                   * be another. If so, and it the new item doesn't need all
                   * the slots, the player then has a choice.  
                   */
                  if ((who->slot[i].used - tmp1->slot[i].info != who->slot[i].info)
                      && abs (op->slot[i].info) < who->slot[i].info)
                    retval |= CAN_APPLY_UNAPPLY_CHOICE;

                  /* Does unequippint 'tmp1' free up enough slots for this to be
                   * equipped?  If not, there must be something else to unapply.
                   */
                  if (who->slot[i].used + op->slot[i].info < tmp1->slot[i].info)
                    retval |= CAN_APPLY_UNAPPLY_MULT;
                }
            }                   /* if not enough free slots */
        }                       /* if this object uses location i */
    }                           /* for i -> num_body_locations loop */

  /* Note that we don't check for FLAG_USE_ARMOUR - that should
   * really be controlled by use of body locations.  We do have
   * the weapon/shield checks, and the range checks for monsters,
   * because you can't control those just by body location - bows, shields,
   * and weapons all use the same slot.  Similar for horn/rod/wand - they
   * all use the same location.
   */
  if (op->type == WEAPON && !QUERY_FLAG (who, FLAG_USE_WEAPON))
    retval |= CAN_APPLY_RESTRICTION;

  if (op->type == SHIELD && !QUERY_FLAG (who, FLAG_USE_SHIELD))
    retval |= CAN_APPLY_RESTRICTION;

  if (who->type != PLAYER)
    {
      if ((op->type == WAND || op->type == HORN || op->type == ROD) && !QUERY_FLAG (who, FLAG_USE_RANGE))
        retval |= CAN_APPLY_RESTRICTION;

      if (op->type == BOW && !QUERY_FLAG (who, FLAG_USE_BOW))
        retval |= CAN_APPLY_RESTRICTION;

      if (op->type == RING && !QUERY_FLAG (who, FLAG_USE_RING))
        retval |= CAN_APPLY_RESTRICTION;

      if (op->type == BOW && !QUERY_FLAG (who, FLAG_USE_BOW))
        retval |= CAN_APPLY_RESTRICTION;
    }

  return retval;
}

/**
 * who is the object using the object.  It can be a monster.
 * op is the object they are using.  op is an equipment type item,
 * eg, one which you put on and keep on for a while, and not something
 * like a potion or scroll.
 *
 * function returns 1 if the action could not be completed, 0 on
 * success.  However, success is a matter of meaning - if the
 * user passes the 'apply' flag to an object already applied,
 * nothing is done, and 0 is returned.
 *
 * aflags is special flags (0 - normal/toggle, AP_APPLY=always apply,
 * AP_UNAPPLY=always unapply).
 *
 * Optional flags:
 *   AP_NO_MERGE: don't merge an unapplied object with other objects
 *   AP_IGNORE_CURSE: unapply cursed items
 *   AP_NO_READY: do not ready skills when applying skill tools
 *
 * Usage example:  apply_special (who, op, AP_UNAPPLY | AP_IGNORE_CURSE)
 *
 * apply_special() doesn't check for unpaid items.
 */

#define LACK_ITEM_POWER \
 " H<You lack enough unused item power to use this weapon, see the skills command.>"

int
apply_special (object *who, object *op, int aflags)
{
  int basic_flag = aflags & AP_BASIC_FLAGS;
  object *tmp, *tmp2, *skop = NULL;

  if (who == NULL)
    {
      LOG (llevError, "apply_special() from object without environment.\n");
      return 1;
    }

  if (op->env != who)
    return 1;                   /* op is not in inventory */

  /* trying to unequip op */
  if (QUERY_FLAG (op, FLAG_APPLIED))
    {
      /* always apply, so no reason to unapply */
      if (basic_flag == AP_APPLY)
        return 0;

      if (!(aflags & AP_IGNORE_CURSE) && (QUERY_FLAG (op, FLAG_CURSED) || QUERY_FLAG (op, FLAG_DAMNED)))
        {
          who->failmsg (format ("No matter how hard you try, you just can't remove %s." CANNOT_REMOVE_CURSED, query_name (op)));
          return 1;
        }

      return unapply_special (who, op, aflags);
    }
  else if (basic_flag == AP_UNAPPLY)
    return 0;

  // if the item is combat/ranged, wield the relevant slot first
  // to resolve conflicts.
  if (player *pl = who->contr)
    switch (op->slottype ())
      {
        case slot_combat: who->change_weapon (pl->combat_ob); break;
        case slot_ranged: who->change_weapon (pl->ranged_ob); break;
      }

  splay (op);

  /* Can't just apply this object.  Lets see what not and what to do */
  if (int i = can_apply_object (who, op))
    {
      if (i & CAN_APPLY_NEVER)
        {
          who->failmsg (format ("You don't have the body to use a %s. H<You can never apply this item.>", query_name (op)));
          return 1;
        }
      else if (i & CAN_APPLY_RESTRICTION)
        {
          who->failmsg (format (
            "You have a prohibition against using a %s. "
            "H<Your belief, profession or class prevents you from applying this item.>",
            query_name (op)
          ));
          return 1;
        }

      if (who->type != PLAYER)
        {
          /* Some error, so don't try to equip something more */
          if (unapply_for_ob (who, op, aflags))
            return 1;
        }
      else
        {
          if (who->contr->unapply == unapply_never || (i & CAN_APPLY_UNAPPLY_CHOICE && who->contr->unapply == unapply_nochoice))
            {
              who->failmsg ("You need to unapply some of the following item(s) or change your applymode:");
              unapply_for_ob (who, op, AP_PRINT);
              return 1;
            }
          else if (who->contr->unapply == unapply_always || !(i & CAN_APPLY_UNAPPLY_CHOICE))
            if (unapply_for_ob (who, op, aflags))
              return 1;
        }
    }

  if (op->skill && op->type != SKILL && op->type != SKILL_TOOL)
    {
      skop = find_skill_by_name (who, op->skill);

      if (!skop)
        {
          who->failmsg (format ("You need the %s skill to use this item!", &op->skill));
          return 1;
        }
      else
        /* While experience will be credited properly, we want to change the
         * skill so that the dam and wc get updated 
         */
        who->change_skill (skop);
    }

  if (!check_item_power (who, op->item_power))
    {
      who->failmsg ("Equipping that combined with other items would consume your soul!" LACK_ITEM_POWER);
      return 1;
    }

  /* Ok.  We are now at the state where we can apply the new object.
   * Note that we don't have the checks for can_use_...
   * below - that is already taken care of by can_apply_object. 
   */
  tmp = op->nrof > 1 ? op->split (op->nrof - 1) : 0;

  if (INVOKE_OBJECT (BE_READY, op, ARG_OBJECT (who)) || INVOKE_OBJECT (READY, who, ARG_OBJECT (op)))
    return RESULT_INT (0);

  switch (op->type)
    {
      case WEAPON:
        //TODO: this obviously fails for players using a shorter prefix
        // i.e. "R" can use Ragnarok's sword.
        if (op->level && !op->name.starts_with (who->name))
          {
            /* if the weapon does not have the name as the character, can't use it. */
            /* (Ragnarok's sword attempted to be used by Foo: won't work) */
            who->failmsg ("The weapon does not recognize you as its owner. H<Its name indicates that it belongs to somebody else.>");

            if (tmp)
              insert_ob_in_ob (tmp, who);

            return 1;
          }

        if (!skop)
          {
            who->failmsg (format ("The %s is broken, please report this to the dungeon master!", query_name (op)));//TODO
            return 1;
          }

        SET_FLAG (op, FLAG_APPLIED);
        who->change_skill (skop);

        if (who->contr)
          who->change_weapon (who->contr->combat_ob = op);

        who->statusmsg (format ("You wield %s.", query_name (op)));

        SET_FLAG (who, FLAG_READY_WEAPON);
        change_abil (who, op);
        break;

      case ARMOUR:
      case HELMET:
      case SHIELD:
      case BOOTS:
      case GLOVES:
      case GIRDLE:
      case BRACERS:
      case CLOAK:
      case RING:
      case AMULET:
        SET_FLAG (op, FLAG_APPLIED);
        who->statusmsg (format ("You wear %s.", query_name (op)));
        change_abil (who, op);
        break;

      case SKILL_TOOL:
        // applying a skill tool also readies the skill
        SET_FLAG (op, FLAG_APPLIED);

        if (!(aflags & AP_NO_READY))
          {
            skop = find_skill_by_name (who, op->skill);
            if (!skop->flag [FLAG_APPLIED])
              apply_special (who, skop, AP_APPLY);
          }
        break;

      case SKILL:
        if (player *pl = who->contr)
          {
            if (IS_COMBAT_SKILL (op->subtype))
              {
                if (skill_flags [op->subtype] & SF_NEED_WEAPON)
                  {
                    for (object *item = who->inv; item; item = item->below)
                      if (item->type == WEAPON && item->flag [FLAG_APPLIED])
                        {
                          if (item->skill == op->skill)
                            {
                              who->change_weapon (pl->combat_ob = item);
                              goto found_weapon;
                            }
                        }

                    who->failmsg (format (
                      "You need to apply a '%s' melee weapon before readying this skill. "
                      "H<Some skills need an item, in this case a melee weapon, to function.>",
                      &op->skill
                    ));
                    return 1;

                    found_weapon:;
                  }
                else
                  who->change_weapon (pl->combat_ob = op);
              }
            else if (IS_RANGED_SKILL (op->subtype))
              {
                if (skill_flags [op->subtype] & SF_NEED_BOW)
                  {
                    for (object *item = who->inv; item; item = item->below)
                      if (item->type == BOW && item->flag [FLAG_APPLIED])
                        {
                          //TODO: bows should/must all have skill missile weapon right now
                          who->change_weapon (pl->ranged_ob = item);
                          goto found_bow;
                        }

                    who->failmsg (
                      "You need to apply a missile weapon before readying this skill. "
                      "H<Some skills need an item, in this case a missile weapon, to function.>"
                    );
                    return 1;

                    found_bow:;
                  }
                else
                  who->change_weapon (pl->ranged_ob = op);
              }

            if (!op->invisible)
              {
                who->statusmsg (format (
                  "You ready %s."
                  "You can now use the skill: %s.",
                  query_name (op),
                  &op->skill
                ));
              }
            else
              who->statusmsg (format ("Readied skill: %s.", op->skill ? &op->skill : &op->name));
          }
        else
          {
            SET_FLAG (op, FLAG_APPLIED);
            change_abil (who, op);
            who->chosen_skill = op;
            SET_FLAG (who, FLAG_READY_SKILL);
          }

        break;

      case BOW:
        if (op->level && !op->name.starts_with (who->name))
          {
            who->failmsg ("The weapon does not recognize you as its owner. "
                           "H<Its name indicates that it belongs to somebody else.>");
            if (tmp)
              insert_ob_in_ob (tmp, who);

            return 1;
          }

       /*FALLTHROUGH*/
      case WAND:
      case ROD:
      case HORN:
        /* check for skill, alter player status */

        if (!skop)
          {
            who->failmsg (format ("The %s is broken, please report this to the dungeon master!", query_name (op)));//TODO
            return 1;
          }

        SET_FLAG (op, FLAG_APPLIED);
        who->change_skill (skop);

        if (who->contr)
          {
            who->contr->ranged_ob = op;

            who->statusmsg (format ("You ready %s.", query_name (op)));

            if (op->type == BOW)
              {
                who->current_weapon = op;
                change_abil (who, op);
                who->statusmsg (format ("You will now fire %s with %s.", op->race ? &op->race : "nothing", query_name (op)));
              }
          }
        else
          {
            if (op->type == BOW)
              SET_FLAG (who, FLAG_READY_BOW);
            else
              SET_FLAG (who, FLAG_READY_RANGE);
          }

        break;

      case BUILDER:
        if (who->type == PLAYER)
          {
            //TODO: wtf does this do? shouldn't this be managed automatically (slots?)
            if (who->contr->ranged_ob && who->contr->ranged_ob->type == BUILDER)
              unapply_special (who, who->contr->ranged_ob, 0);

            who->statusmsg (format ("You ready your %s.", query_name (op)));

            who->contr->ranged_ob = op;
          }
        break;

      default:
        who->statusmsg (format ("You apply %s.", query_name (op)));
    }

  SET_FLAG (op, FLAG_APPLIED);

  if (tmp)
    who->insert (tmp);

  who->update_stats ();

  /* We exclude spell casting objects.  The fire code will set the
   * been applied flag when they are used - until that point,
   * you don't know anything about them.
   */
  if (who->type == PLAYER && op->type != WAND && op->type != HORN && op->type != ROD)
    SET_FLAG (op, FLAG_BEEN_APPLIED);

  if (QUERY_FLAG (op, FLAG_CURSED) || QUERY_FLAG (op, FLAG_DAMNED))
    if (who->type == PLAYER)
      {
        who->failmsg (
          "Oops, it feels deadly cold! "
          "H<Maybe it wasn't such a bright idea to apply this cursed or damned item.>"
        );
        SET_FLAG (op, FLAG_KNOWN_CURSED);
      }

  if (object *pl = op->visible_to ())
    esrv_send_item (pl, op);

  return 0;
}

int
monster_apply_special (object *who, object *op, int aflags)
{
  if (QUERY_FLAG (op, FLAG_UNPAID) && !QUERY_FLAG (op, FLAG_APPLIED))
    return 1;

  return apply_special (who, op, aflags);
}

/**
 * Map was just loaded, handle op's initialisation.
 *
 * Generates shop floor's item, and treasures.
 */
int
auto_apply (object *op)
{
  object *tmp = NULL, *tmp2;
  int i;

  CLEAR_FLAG (op, FLAG_AUTO_APPLY);

  switch (op->type)
    {
      case SHOP_FLOOR:
        if (!op->has_random_items ())
          return 0;

        do
          {
            i = 10;             /* let's give it 10 tries */
            while ((tmp = generate_treasure (op->randomitems,
                                             op->stats.exp
                                               ? (int) op->stats.exp
                                               : max (op->map->difficulty, 5)))
                   == NULL && --i);

            if (tmp == NULL)
              return 0;

            if (QUERY_FLAG (tmp, FLAG_CURSED) || QUERY_FLAG (tmp, FLAG_DAMNED))
              {
                tmp->destroy ();
                tmp = NULL;
              }
          }
        while (!tmp);

        tmp->x = op->x;
        tmp->y = op->y;
        SET_FLAG (tmp, FLAG_UNPAID);
        insert_ob_in_map (tmp, op->map, NULL, 0);
        identify (tmp);
        break;

      case TREASURE:
        if (QUERY_FLAG (op, FLAG_IS_A_TEMPLATE))
          return 0;

        while (op->stats.hp-- > 0)
          create_treasure (op->randomitems, op, op->map ? GT_ENVIRONMENT : 0,
                           op->stats.exp ? (int) op->stats.exp : op->map == NULL ? 14 : op->map->difficulty, 0);

        /* If we generated an object and put it in this object inventory,
         * move it to the parent object as the current object is about
         * to disappear.  An example of this item is the random_* stuff
         * that is put inside other objects.
         */
        if (op->env)
          while (op->inv)
            op->env->insert (op->inv);

        op->destroy ();
        break;
    }

  return !!tmp;
}

/**
 * fix_auto_apply goes through the entire map every time a map
 * is loaded or swapped in and performs special actions for
 * certain objects (most initialization of chests and creation of
 * treasures and stuff).  Calls auto_apply if appropriate.
 */
void
maptile::fix_auto_apply ()
{
  if (!spaces)
    return;

  for (mapspace *ms = spaces + size (); ms-- > spaces; )
    for (object *tmp = ms->bot; tmp; )
      {
        object *above = tmp->above;

        if (tmp->inv)
          {
            object *invtmp, *invnext;

            for (invtmp = tmp->inv; invtmp; invtmp = invnext)
              {
                invnext = invtmp->below;

                if (QUERY_FLAG (invtmp, FLAG_AUTO_APPLY))
                  auto_apply (invtmp);
                else if (invtmp->type == TREASURE && invtmp->has_random_items ())
                  {
                    while (invtmp->stats.hp-- > 0)
                      create_treasure (invtmp->randomitems, invtmp, 0, difficulty, 0);

                    invtmp->randomitems = NULL;
                  }
                else if (invtmp && invtmp->arch
                         && invtmp->type != TREASURE && invtmp->type != SPELL && invtmp->type != CLASS && invtmp->has_random_items ())
                  {
                    create_treasure (invtmp->randomitems, invtmp, 0, difficulty, 0);
                    /* Need to clear this so that we never try to create 
                     * treasure again for this object
                     */
                    invtmp->randomitems = NULL;
                  }
              }
            /* This is really temporary - the code at the bottom will
             * also set randomitems to null.  The problem is there are bunches
             * of maps/players already out there with items that have spells
             * which haven't had the randomitems set to null yet.
             * MSW 2004-05-13
             *
             * And if it's a spellbook, it's better to set randomitems to NULL too,
             * else you get two spells in the book ^_-
             * Ryo 2004-08-16
             */
            if (tmp->type == WAND || tmp->type == ROD || tmp->type == SCROLL
                || tmp->type == HORN || tmp->type == FIREWALL || tmp->type == POTION || tmp->type == ALTAR || tmp->type == SPELLBOOK)
              tmp->randomitems = NULL;

          }

        if (QUERY_FLAG (tmp, FLAG_AUTO_APPLY))
          auto_apply (tmp);
        else if ((tmp->type == TREASURE || (tmp->type == CONTAINER)) && tmp->has_random_items ())
          {
            while ((tmp->stats.hp--) > 0)
              create_treasure (tmp->randomitems, tmp, 0, difficulty, 0);
            tmp->randomitems = NULL;
          }
        else if (tmp->type == TIMED_GATE)
          {
            object *head = tmp->head != NULL ? tmp->head : tmp;

            if (QUERY_FLAG (head, FLAG_IS_LINKED))
              tmp->set_speed (0);
          }
        /* This function can be called everytime a map is loaded, even when
         * swapping back in.  As such, we don't want to create the treasure
         * over and ove again, so after we generate the treasure, blank out
         * randomitems so if it is swapped in again, it won't make anything.
         * This is a problem for the above objects, because they have counters
         * which say how many times to make the treasure.
         */
        else if (tmp && tmp->arch && tmp->type != PLAYER
                 && tmp->type != TREASURE && tmp->type != SPELL
                 && tmp->type != PLAYER_CHANGER && tmp->type != CLASS && tmp->has_random_items ())
          {
            create_treasure (tmp->randomitems, tmp, GT_APPLY, difficulty, 0);
            tmp->randomitems = NULL;
          }

        // close all containers
        else if (tmp->type == CONTAINER)
          tmp->flag [FLAG_APPLIED] = 0;

        tmp = above;
      }

  for (mapspace *ms = spaces + size (); ms-- > spaces; )
    for (object *tmp = ms->bot; tmp; tmp = tmp->above)
      if (tmp->above && (tmp->type == TRIGGER_BUTTON || tmp->type == TRIGGER_PEDESTAL))
        check_trigger (tmp, tmp->above);
}

/**
 * Handles player eating food that temporarily changes status (resistances, stats).
 * This used to call cast_change_attr(), but
 * that doesn't work with the new spell code.  Since we know what
 * the food changes, just grab a force and use that instead.
 */
void
eat_special_food (object *who, object *food)
{
  object *force;
  int i, did_one = 0;

  force = get_archetype (FORCE_NAME);

  for (i = 0; i < NUM_STATS; i++)
    if (sint8 k = food->stats.stat (i))
      {
        force->stats.stat (i) = k;
        did_one = 1;
      }

  /* check if we can protect the eater */
  for (i = 0; i < NROFATTACKS; i++)
    {
      if (food->resist[i] > 0)
        {
          force->resist[i] = food->resist[i] / 2;
          did_one = 1;
        }
    }

  if (did_one)
    {
      force->set_speed (0.1);
      /* bigger morsel of food = longer effect time */
      force->duration = food->stats.food / 5;
      SET_FLAG (force, FLAG_APPLIED);
      change_abil (who, force);
      insert_ob_in_ob (force, who);
    }
  else
    force->destroy ();

  /* check for hp, sp change */
  if (food->stats.hp != 0)
    {
      if (QUERY_FLAG (food, FLAG_CURSED))
        {
          who->contr->killer = food;
          hit_player (who, food->stats.hp, food, AT_POISON, 1);
          who->failmsg ("Eck!...that was poisonous!");
        }
      else
        {
          if (food->stats.hp > 0)
            who->statusmsg ("You begin to feel better.");
          else
            who->failmsg ("Eck!...that was poisonous!");

          who->stats.hp += food->stats.hp;
        }
    }

  if (food->stats.sp != 0)
    {
      if (QUERY_FLAG (food, FLAG_CURSED))
        {
          who->failmsg ("You are drained of mana!");
          who->stats.sp -= food->stats.sp;
          if (who->stats.sp < 0)
            who->stats.sp = 0;
        }
      else
        {
          who->statusmsg ("You feel a rush of magical energy!");
          who->stats.sp += food->stats.sp;
          /* place limit on max sp from food? */
        }
    }

  who->update_stats ();
}


/**
 * op made some mistake with a scroll, this takes care of punishment.
 * scroll_failure()- hacked directly from spell_failure
 */
void
scroll_failure (object *op, int failure, int power)
{
  if (abs (failure / 4) > power)
    power = abs (failure / 4);  /* set minimum effect */

  if (failure <= -1 && failure > -15)
    {                           /* wonder */
      object *tmp;

      op->failmsg ("Your spell warps!");
      tmp = get_archetype (SPELL_WONDER);
      cast_wonder (op, op, 0, tmp);
      tmp->destroy ();
    }
  else if (failure <= -15 && failure > -35)
    {                           /* drain mana */
      op->failmsg ("Your mana is drained!");
      op->stats.sp -= random_roll (0, power - 1, op, PREFER_LOW);
      if (op->stats.sp < 0)
        op->stats.sp = 0;
    }
  else if (settings.spell_failure_effects == TRUE)
    {
      if (failure <= -35 && failure > -60)
        {                       /* confusion */
          op->failmsg ("The magic recoils on you!");
          confuse_player (op, op, power);
        }
      else if (failure <= -60 && failure > -70)
        {                       /* paralysis */
          op->failmsg ("The magic recoils and paralyzes you!");
          paralyze_player (op, op, power);
        }
      else if (failure <= -70 && failure > -80)
        {                       /* blind */
          op->failmsg ("The magic recoils on you!");
          blind_player (op, op, power);
        }
      else if (failure <= -80)
        {                       /* blast the immediate area */
          object *tmp = get_archetype (LOOSE_MANA);
          cast_magic_storm (op, tmp, power);
          op->failmsg ("You unleash uncontrolled mana!");
          tmp->destroy ();
        }
    }
}

void
apply_changes_to_player (object *pl, object *change)
{
  int excess_stat = 0;          /* if the stat goes over the maximum
                                   for the race, put the excess stat some
                                   where else. */

  switch (change->type)
    {
      case CLASS:
        {
          living *stats = &(pl->contr->orig_stats);
          living *ns = &(change->stats);
          object *walk;
          int flag_change_face = 1;

          /* the following code assigns stats up to the stat max
           * for the race, and if the stat max is exceeded,
           * tries to randomly reassign the excess stat
           */
          int i, j;

          for (i = 0; i < NUM_STATS; i++)
            {
              int race_bonus = pl->arch->stats.stat (i);
              sint8 stat = stats->stat (i) + ns->stat (i);

              if (stat > 20 + race_bonus)
                {
                  excess_stat++;
                  stat = 20 + race_bonus;
                }

              stats->stat (i) = stat;
            }

          for (j = 0; excess_stat > 0 && j < 100; j++)
            {                   /* try 100 times to assign excess stats */
              int i = rndm (0, 6);

              if (i == CHA)
                continue;       /* exclude cha from this */

              int stat = stats->stat (i);
              int race_bonus = pl->arch->stats.stat (i);
              if (stat < 20 + race_bonus)
                {
                  change_attr_value (stats, i, 1);
                  excess_stat--;
                }
            }

          /* insert the randomitems from the change's treasurelist into
           * the player ref: player.c
           */
          if (change->randomitems)
            give_initial_items (pl, change->randomitems);

          /* set up the face, for some races. */

          /* first, look for the force object banning
           * changing the face.  Certain races never change face with class.
           */
          for (walk = pl->inv; walk; walk = walk->below)
            if (walk->name == shstr_NOCLASSFACECHANGE)
              flag_change_face = 0;

          if (flag_change_face)
            {
              pl->face                = change->face;
              pl->animation_id        = change->animation_id;
              pl->flag [FLAG_ANIMATE] = change->flag [FLAG_ANIMATE];
            }

          /* check the special case of can't use weapons */
          /*if(QUERY_FLAG(change,FLAG_USE_WEAPON)) CLEAR_FLAG(pl,FLAG_USE_WEAPON); */
          if (change->name == shstr_monk)
            CLEAR_FLAG (pl, FLAG_USE_WEAPON);

          break;
        }
    }
}

/**
 * This handles items of type 'transformer'.
 * Basically those items, used with a marked item, transform both items into something
 * else.
 * "Transformer" item has food decreased by 1, removed if 0 (0 at start means illimited)..
 * Change information is contained in the 'slaying' field of the marked item.
 * The format is as follow: transformer:[number ]yield[;transformer:...].
 * This way an item can be transformed in many things, and/or many objects.
 * The 'slaying' field for transformer is used as verb for the action.
 */
void
apply_item_transformer (object *pl, object *transformer)
{
  object *marked;
  object *new_item;
  char *find;
  char *separator;
  int yield;
  char got[MAX_BUF];
  int len;

  if (!pl || !transformer)
    return;

  marked = find_marked_object (pl);

  if (!marked)
    {
      pl->failmsg (format ("Use the %s with what item?", query_name (transformer)));
      return;
    }

  if (!marked->slaying)
    {
      pl->failmsg (format ("You can't use the %s with your %s!", query_name (transformer), query_name (marked)));
      return;
    }

  /* check whether they are compatible or not */
  find = strstr (&marked->slaying, transformer->arch->archname);
  if (!find || (*(find + strlen (transformer->arch->archname)) != ':'))
    {
      pl->failmsg (format ("You can't use the %s with your %s!", query_name (transformer), query_name (marked)));
      return;
    }

  find += strlen (transformer->arch->archname) + 1;
  /* Item can be used, now find how many and what it yields */
  if (isdigit (*(find)))
    {
      yield = atoi (find);
      if (yield < 1)
        {
          LOG (llevDebug, "apply_item_transformer: item %s has slaying-yield %d.", query_base_name (marked, 0), yield);
          yield = 1;
        }
    }
  else
    yield = 1;

  while (isdigit (*find))
    find++;

  while (*find == ' ')
    find++;

  memset (got, 0, MAX_BUF);

  if ((separator = strchr (find, ';')) != NULL)
    len = separator - find;
  else
    len = strlen (find);

  if (len > MAX_BUF - 1)
    len = MAX_BUF - 1;

  strcpy (got, find);
  got[len] = '\0';

  /* Now create new item, remove used ones when required. */
  new_item = get_archetype (got);
  if (!new_item)
    {
      pl->failmsg (format ("This %s is strange, better to not use it.", query_base_name (marked, 0)));
      return;
    }

  new_item->nrof = yield;

  pl->statusmsg (format ("You %s the %s.", &transformer->slaying, query_base_name (marked, 0)));

  pl->insert (new_item);
  /* Eat up one item */
  marked->decrease ();

  /* Eat one transformer if needed */
  if (transformer->stats.food)
    if (--transformer->stats.food == 0)
      transformer->decrease ();
}