/*
 *  File:       monster.cc
 *  Summary:    Monsters class methods
 *  Written by: Linley Henzell
 */

#include "AppHdr.h"

#include "areas.h"
#include "beam.h"
#include "cloud.h"
#include "coordit.h"
#include "delay.h"
#include "dgnevent.h"
#include "dgn-shoals.h"
#include "directn.h"
#include "env.h"
#include "fight.h"
#include "fprop.h"
#include "ghost.h"
#include "goditem.h"
#include "itemname.h"
#include "items.h"
#include "kills.h"
#include "misc.h"
#include "mon-abil.h"
#include "mon-behv.h"
#include "mon-place.h"
#include "terrain.h"
#include "mgen_data.h"
#include "coord.h"
#include "mon-stuff.h"
#include "mon-transit.h"
#include "random.h"
#include "religion.h"
#include "shopping.h"
#include "spl-util.h"
#include "state.h"
#include "stuff.h"
#include "traps.h"
#include "tutorial.h"
#include "view.h"
#include "shout.h"
#include "xom.h"

#include <algorithm>

struct mon_spellbook
{
    mon_spellbook_type type;
    spell_type spells[NUM_MONSTER_SPELL_SLOTS];
};

static mon_spellbook mspell_list[] = {
#include "mon-spll.h"
};

// Macro that saves some typing, nothing more.
#define smc get_monster_data(mc)

monsters::monsters()
    : type(MONS_NO_MONSTER), hit_points(0), max_hit_points(0), hit_dice(0),
      ac(0), ev(0), speed(0), speed_increment(0), target(), patrol_point(),
      travel_target(MTRAV_NONE), inv(NON_ITEM), spells(),
      attitude(ATT_HOSTILE), behaviour(BEH_WANDER), foe(MHITYOU),
      enchantments(), flags(0L), experience(0), base_monster(MONS_NO_MONSTER),
      number(0), colour(BLACK), foe_memory(0), shield_blocks(0),
      god(GOD_NO_GOD), ghost(), seen_context(""), props()

{
    travel_path.clear();
    if (crawl_state.arena)
        foe = MHITNOT;
}

// Empty destructor to keep auto_ptr happy with incomplete ghost_demon type.
monsters::~monsters()
{
}

monsters::monsters(const monsters &mon)
{
    init_with(mon);
}

monsters &monsters::operator = (const monsters &mon)
{
    if (this != &mon)
        init_with(mon);
    return (*this);
}

void monsters::reset()
{
    mname.clear();
    enchantments.clear();
    ench_countdown = 0;
    inv.init(NON_ITEM);

    flags           = 0;
    experience      = 0L;
    type            = MONS_NO_MONSTER;
    base_monster    = MONS_NO_MONSTER;
    hit_points      = 0;
    max_hit_points  = 0;
    hit_dice        = 0;
    ac              = 0;
    ev              = 0;
    speed_increment = 0;
    attitude        = ATT_HOSTILE;
    behaviour       = BEH_SLEEP;
    foe             = MHITNOT;
    number          = 0;

    if (in_bounds(pos()))
        mgrd(pos()) = NON_MONSTER;

    position.reset();
    patrol_point.reset();
    travel_target = MTRAV_NONE;
    travel_path.clear();
    ghost.reset(NULL);
    seen_context = "";
    props.clear();
}

void monsters::init_with(const monsters &mon)
{
    mname             = mon.mname;
    type              = mon.type;
    base_monster      = mon.base_monster;
    hit_points        = mon.hit_points;
    max_hit_points    = mon.max_hit_points;
    hit_dice          = mon.hit_dice;
    ac                = mon.ac;
    ev                = mon.ev;
    speed             = mon.speed;
    speed_increment   = mon.speed_increment;
    position          = mon.position;
    target            = mon.target;
    patrol_point      = mon.patrol_point;
    travel_target     = mon.travel_target;
    travel_path       = mon.travel_path;
    inv               = mon.inv;
    spells            = mon.spells;
    attitude          = mon.attitude;
    behaviour         = mon.behaviour;
    foe               = mon.foe;
    enchantments      = mon.enchantments;
    flags             = mon.flags;
    experience        = mon.experience;
    number            = mon.number;
    colour            = mon.colour;
    foe_memory        = mon.foe_memory;
    god               = mon.god;
    props             = mon.props;

    if (mon.ghost.get())
        ghost.reset(new ghost_demon(*mon.ghost));
    else
        ghost.reset(NULL);
}

mon_attitude_type monsters::temp_attitude() const
{
    if (has_ench(ENCH_CHARM))
        return ATT_FRIENDLY;
    else if (has_ench(ENCH_TEMP_PACIF))
        return ATT_GOOD_NEUTRAL;
    else
        return attitude;
}

bool monsters::swimming() const
{
    const dungeon_feature_type grid = grd(pos());
    return (feat_is_watery(grid) && mons_primary_habitat(this) == HT_WATER);
}

static bool _player_near_water()
{
    for (adjacent_iterator ai(you.pos()); ai; ++ai)
        if (feat_is_water(grd(*ai)))
            return (true);

    return (false);
}

bool monsters::wants_submerge() const
{
    // Krakens never retreat when food (the player) is in range.
    if (mons_base_type(this) == MONS_KRAKEN && _player_near_water())
        return (false);

    // If we're in distress, we usually want to submerge.
    if (env.cgrid(pos()) != EMPTY_CLOUD
        || (hit_points < max_hit_points / 2
            && random2(max_hit_points + 1) >= hit_points))
    {
        return (true);
    }

    // Trapdoor spiders only hide themselves under the floor when they
    // can't see their prey.
    if (type == MONS_TRAPDOOR_SPIDER)
    {
        const actor* _foe = get_foe();
        return (_foe == NULL || !can_see(_foe));
    }

    const bool has_ranged_attack = (type == MONS_ELECTRIC_EEL
                                    || type == MONS_LAVA_SNAKE
                                    || mons_genus(type) == MONS_MERMAID
                                       && you.species != SP_MERFOLK);

    int roll = 8;
    // Shallow water takes a little more effort to submerge in, so we're
    // less likely to bother.
    if (grd(pos()) == DNGN_SHALLOW_WATER)
        roll = roll * 7 / 5;

    const actor *tfoe = get_foe();
    if (tfoe && grid_distance(tfoe->pos(), pos()) > 1 && !has_ranged_attack)
        roll /= 2;

    // Don't submerge if we just unsubmerged to shout
    return (one_chance_in(roll) && seen_context != "bursts forth shouting");
}

bool monsters::submerged() const
{
    // FIXME, switch to 4.1's MF_SUBMERGED system which is much cleaner.
    // Can't find any reference to MF_SUBMERGED anywhere. Don't know what
    // this means. - abrahamwl
    if (has_ench(ENCH_SUBMERGED))
        return (true);

    if (grd(pos()) == DNGN_DEEP_WATER
        && !monster_habitable_grid(this, DNGN_DEEP_WATER))
    {
        return (true);
    }

    return (false);
}

bool monsters::extra_balanced() const
{
    return (mons_genus(type) == MONS_NAGA);
}

bool monsters::floundering() const
{
    const dungeon_feature_type grid = grd(pos());
    return (feat_is_water(grid)
            && !cannot_fight()
            // Can't use monster_habitable_grid() because that'll return
            // true for non-water monsters in shallow water.
            && mons_primary_habitat(this) != HT_WATER
            && !mons_amphibious(this)
            && !mons_flies(this)
            && !extra_balanced());
}

bool monsters::can_pass_through_feat(dungeon_feature_type grid) const
{
    return mons_can_pass(this, grid);
}

bool monsters::is_habitable_feat(dungeon_feature_type actual_grid) const
{
    return monster_habitable_grid(this, actual_grid);
}

bool monsters::can_drown() const
{
    // Presumably a shark in lava or a lavafish in deep water could
    // drown, but that should never happen, so this simple check should
    // be enough.
    switch (mons_primary_habitat(this))
    {
    case HT_WATER:
    case HT_LAVA:
        return (false);
    default:
        break;
    }

    // Mummies can fall apart in water or be incinerated in lava.
    // Ghouls, vampires, and demons can drown in water or lava.  Others
    // just "sink like a rock", to never be seen again.
    return (!res_asphyx()
            || mons_genus(type) == MONS_MUMMY
            || mons_genus(type) == MONS_GHOUL
            || mons_genus(type) == MONS_VAMPIRE
            || holiness() == MH_DEMONIC);
}

size_type monsters::body_size(size_part_type /* psize */, bool /* base */) const
{
    const monsterentry *e = get_monster_data(type);
    size_type ret = (e ? e->size : SIZE_MEDIUM);

    // Slime creature size is increased by the number merged.
    if (type == MONS_SLIME_CREATURE)
    {
        if (number == 2)
            ret = SIZE_MEDIUM;
        else if (number == 3)
            ret = SIZE_LARGE;
        else if (number == 4)
            ret = SIZE_BIG;
        else if (number == 5)
            ret = SIZE_GIANT;
    }

    return (ret);
}

int monsters::body_weight(bool /*base*/) const
{
    int mclass = type;

    switch (mclass)
    {
    case MONS_SPECTRAL_THING:
    case MONS_SPECTRAL_WARRIOR:
    case MONS_ELECTRIC_GOLEM:
    case MONS_RAKSHASA_FAKE:
    case MONS_MARA_FAKE:
        return (0);

    case MONS_ZOMBIE_SMALL:
    case MONS_ZOMBIE_LARGE:
    case MONS_SKELETON_SMALL:
    case MONS_SKELETON_LARGE:
    case MONS_SIMULACRUM_SMALL:
    case MONS_SIMULACRUM_LARGE:
        mclass = number;
        break;

    default:
        break;
    }

    int weight = mons_weight(mclass);

    // weight == 0 in the monster entry indicates "no corpse".  Can't
    // use CE_NOCORPSE, because the corpse-effect field is used for
    // corpseless monsters to indicate what happens if their blood
    // is sucked.  Grrrr.
    if (weight == 0 && !mons_is_insubstantial(type))
    {
        weight = actor::body_weight();

        switch (mclass)
        {
        case MONS_IRON_DEVIL:
            weight += 550;
            break;

        case MONS_STONE_GOLEM:
        case MONS_EARTH_ELEMENTAL:
        case MONS_CRYSTAL_GOLEM:
            weight *= 2;
            break;

        case MONS_IRON_DRAGON:
        case MONS_IRON_GOLEM:
            weight *= 3;
            break;

        case MONS_QUICKSILVER_DRAGON:
        case MONS_SILVER_STATUE:
        case MONS_STATUE:
            weight *= 4;
            break;

        case MONS_WOOD_GOLEM:
            weight *= 2;
            weight /= 3;
            break;

        case MONS_FLYING_SKULL:
        case MONS_CURSE_SKULL:
        case MONS_SKELETAL_DRAGON:
        case MONS_SKELETAL_WARRIOR:
            weight /= 2;
            break;

        case MONS_SHADOW_FIEND:
        case MONS_SHADOW_IMP:
        case MONS_SHADOW_DEMON:
            weight /= 3;
            break;
        }

        switch (mons_char(mclass))
        {
        case 'L':
            weight /= 2;
            break;

        case 'p':
            weight = 0;
            break;
        }
    }

    if (type == MONS_SKELETON_SMALL || type == MONS_SKELETON_LARGE)
        weight /= 2;

    // Slime creature weight is multiplied by the number merged.
    if (type == MONS_SLIME_CREATURE && number > 1)
        weight *= number;

    return (weight);
}

int monsters::total_weight() const
{
    int burden = 0;

    for (int i = 0; i < NUM_MONSTER_SLOTS; i++)
        if (inv[i] != NON_ITEM)
            burden += item_mass(mitm[inv[i]]) * mitm[inv[i]].quantity;

    return (body_weight() + burden);
}

int monsters::damage_brand(int which_attack)
{
    const item_def *mweap = weapon(which_attack);

    if (!mweap)
    {
        if (mons_is_ghost_demon(type))
            return (ghost->brand);

        return (SPWPN_NORMAL);
    }

    return (!is_range_weapon(*mweap) ? get_weapon_brand(*mweap) : SPWPN_NORMAL);
}

int monsters::damage_type(int which_attack)
{
    const item_def *mweap = weapon(which_attack);

    if (!mweap)
    {
        const mon_attack_def atk = mons_attack_spec(this, which_attack);
        return ((atk.type == AT_CLAW)          ? DVORP_CLAWING :
                (atk.type == AT_TENTACLE_SLAP) ? DVORP_TENTACLE
                                               : DVORP_CRUSHING);
    }

    return (get_vorpal_type(*mweap));
}

item_def *monsters::missiles()
{
    return (inv[MSLOT_MISSILE] != NON_ITEM ? &mitm[inv[MSLOT_MISSILE]] : NULL);
}

int monsters::missile_count()
{
    if (const item_def *missile = missiles())
        return (missile->quantity);

    return (0);
}

item_def *monsters::launcher()
{
    item_def *weap = mslot_item(MSLOT_WEAPON);
    if (weap && is_range_weapon(*weap))
        return (weap);

    weap = mslot_item(MSLOT_ALT_WEAPON);
    return (weap && is_range_weapon(*weap) ? weap : NULL);
}

// Does not check whether the monster can dual-wield - that is the
// caller's responsibility.
static int _mons_offhand_weapon_index(const monsters *m)
{
    return (m->inv[MSLOT_ALT_WEAPON]);
}

item_def *monsters::weapon(int which_attack)
{
    const mon_attack_def attk = mons_attack_spec(this, which_attack);
    if (attk.type != AT_HIT && attk.type != AT_WEAP_ONLY)
        return (NULL);

    // Even/odd attacks use main/offhand weapon.
    if (which_attack > 1)
        which_attack &= 1;

    // This randomly picks one of the wielded weapons for monsters that can use
    // two weapons. Not ideal, but better than nothing. fight.cc does it right,
    // for various values of right.
    int weap = inv[MSLOT_WEAPON];

    if (which_attack && mons_wields_two_weapons(this))
    {
        const int offhand = _mons_offhand_weapon_index(this);
        if (offhand != NON_ITEM
            && (weap == NON_ITEM || which_attack == 1 || coinflip()))
        {
            weap = offhand;
        }
    }

    return (weap == NON_ITEM ? NULL : &mitm[weap]);
}

bool monsters::can_wield(const item_def& item, bool ignore_curse,
                         bool ignore_brand, bool ignore_shield,
                         bool ignore_transform) const
{
    // Monsters can only wield weapons or go unarmed (OBJ_UNASSIGNED
    // means unarmed).
    if (item.base_type != OBJ_WEAPONS && item.base_type != OBJ_UNASSIGNED)
        return (false);

    // These *are* weapons, so they can't wield another weapon or
    // unwield themselves.
    if (type == MONS_DANCING_WEAPON)
        return (false);

    // MF_HARD_RESET means that all items the monster is carrying will
    // disappear when it does, so it can't accept new items or give up
    // the ones it has.
    if (flags & MF_HARD_RESET)
        return (false);

    // Summoned items can only be held by summoned monsters.
    if ((item.flags & ISFLAG_SUMMONED) && !is_summoned())
        return (false);

    item_def* weap1 = NULL;
    if (inv[MSLOT_WEAPON] != NON_ITEM)
        weap1 = &mitm[inv[MSLOT_WEAPON]];

    int       avail_slots = 1;
    item_def* weap2       = NULL;
    if (mons_wields_two_weapons(this))
    {
        if (!weap1 || hands_reqd(*weap1, body_size()) != HANDS_TWO)
            avail_slots = 2;

        const int offhand = _mons_offhand_weapon_index(this);
        if (offhand != NON_ITEM)
            weap2 = &mitm[offhand];
    }

    // If we're already wielding it, then of course we can wield it.
    if (&item == weap1 || &item == weap2)
        return (true);

    // Barehanded needs two hands.
    const bool two_handed = item.base_type == OBJ_UNASSIGNED
                            || hands_reqd(item, body_size()) == HANDS_TWO;

    item_def* _shield = NULL;
    if (inv[MSLOT_SHIELD] != NON_ITEM)
    {
        ASSERT(!(weap1 && weap2));

        if (two_handed && !ignore_shield)
            return (false);

        _shield = &mitm[inv[MSLOT_SHIELD]];
    }

    if (!ignore_curse)
    {
        int num_cursed = 0;
        if (weap1 && weap1->cursed())
            num_cursed++;
        if (weap2 && weap2->cursed())
            num_cursed++;
        if (_shield && _shield->cursed())
            num_cursed++;

        if (two_handed && num_cursed > 0 || num_cursed >= avail_slots)
            return (false);
    }

    return could_wield(item, ignore_brand, ignore_transform);
}

bool monsters::could_wield(const item_def &item, bool ignore_brand,
                           bool /* ignore_transform */) const
{
    ASSERT(item.is_valid());

    // These *are* weapons, so they can't wield another weapon.
    if (type == MONS_DANCING_WEAPON)
        return (false);

    // Monsters can't use unrandarts with special effects.
    if (is_special_unrandom_artefact(item) && !crawl_state.arena)
        return (false);

    // Wimpy monsters (e.g. kobolds, goblins) can't use halberds, etc.
    if (!check_weapon_wieldable_size(item, body_size()))
        return (false);

    if (!ignore_brand)
    {
        const int brand = get_weapon_brand(item);

        // Draconians won't use dragon slaying weapons.
        if (brand == SPWPN_DRAGON_SLAYING && is_dragonkind(this))
            return (false);

        // Orcs won't use orc slaying weapons.
        if (brand == SPWPN_ORC_SLAYING && is_orckind(this))
            return (false);

        // Undead and demonic monsters won't use holy weapons.
        if (undead_or_demonic() && is_holy_item(item))
            return (false);

        // Holy monsters and monsters that are gifts of good gods won't
        // use unholy weapons.
        if ((is_holy() || is_good_god(god)) && is_unholy_item(item))
            return (false);

        // Holy monsters that aren't gifts of chaotic gods and monsters
        // that are gifts of good gods or Fedhas won't use potentially
        // evil weapons.
        if (((is_holy() && !is_chaotic_god(god))
                || (is_good_god(god) || god == GOD_FEDHAS))
            && is_potentially_evil_item(item))
        {
            return (false);
        }

        // Holy monsters and monsters that are gifts of good gods or
        // Fedhas won't use evil weapons.
        if (((is_holy() || is_good_god(god)) || god == GOD_FEDHAS)
            && is_evil_item(item))
        {
            return (false);
        }

        // Holy monsters that aren't gifts of chaotic gods and monsters
        // that are gifts of good gods won't use chaotic weapons.
        if (((is_holy() && !is_chaotic_god(god)) || is_good_god(god))
            && is_chaotic_item(item))
        {
            return (false);
        }

        // Monsters that are gifts of Zin won't use unclean weapons.
        if (god == GOD_ZIN && is_unclean_item(item))
            return (false);
    }

    return (true);
}

bool monsters::can_throw_large_rocks() const
{
    return (type == MONS_STONE_GIANT
            || ::mons_species(type) == MONS_CYCLOPS
            || ::mons_species(type) == MONS_OGRE);
}

bool monsters::can_speak()
{
    // Priest and wizard monsters can always speak.
    if (is_priest() || is_actual_spellcaster())
        return (true);

    // Silent or non-sentient monsters can't use the original speech.
    if (mons_intel(this) < I_NORMAL
        || mons_shouts(type) == S_SILENT)
    {
        return (false);
    }

    // Does it have the proper vocal equipment?
    const mon_body_shape shape = get_mon_shape(this);
    return (shape >= MON_SHAPE_HUMANOID && shape <= MON_SHAPE_NAGA);
}

bool monsters::has_spell_of_type(unsigned disciplines) const
{
    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
    {
        if (spells[i] == SPELL_NO_SPELL)
            continue;

        if (spell_typematch(spells[i], disciplines))
            return (true);
    }
    return (false);
}

void monsters::bind_spell_flags()
{
    // Bind spellcaster / priest flags from the base type. These may be
    // overridden by vault defs for individual monsters.

    // Alas, we don't know if the mon is zombified at the moment, if it is,
    // the flags will be removed later.
    if (mons_class_flag(type, M_SPELLCASTER))
        flags |= MF_SPELLCASTER;
    if (mons_class_flag(type, M_ACTUAL_SPELLS))
        flags |= MF_ACTUAL_SPELLS;
    if (mons_class_flag(type, M_PRIEST))
        flags |= MF_PRIEST;
}

static bool _needs_ranged_attack(const monsters *mon)
{
    // Prevent monsters that have conjurations from grabbing missiles.
    if (mon->has_spell_of_type(SPTYP_CONJURATION))
        return (false);

    // Same for summonings, but make an exception for friendlies.
    if (!mon->friendly() && mon->has_spell_of_type(SPTYP_SUMMONING))
        return (false);

    // Blademasters don't want to throw stuff.
    if (mon->type == MONS_DEEP_ELF_BLADEMASTER)
        return (false);

    return (true);
}

bool monsters::can_use_missile(const item_def &item) const
{
    // Don't allow monsters to pick up missiles without the corresponding
    // launcher. The opposite is okay, and sufficient wandering will
    // hopefully take the monster to a stack of appropriate missiles.

    if (!_needs_ranged_attack(this))
        return (false);

    if (item.base_type == OBJ_WEAPONS
        || item.base_type == OBJ_MISSILES && !has_launcher(item))
    {
        return (is_throwable(this, item));
    }

    // Stones are allowed even without launcher.
    if (item.sub_type == MI_STONE)
        return (true);

    item_def *launch;
    for (int i = MSLOT_WEAPON; i <= MSLOT_ALT_WEAPON; ++i)
    {
        launch = mslot_item(static_cast<mon_inv_type>(i));
        if (launch && fires_ammo_type(*launch) == item.sub_type)
            return (true);
    }

    // No fitting launcher in inventory.
    return (false);
}

void monsters::swap_slots(mon_inv_type a, mon_inv_type b)
{
    const int swap = inv[a];
    inv[a] = inv[b];
    inv[b] = swap;
}

void monsters::equip_weapon(item_def &item, int near, bool msg)
{
    if (msg && !need_message(near))
        msg = false;

    if (msg)
    {
        snprintf(info, INFO_SIZE, " wields %s.",
                 item.name(DESC_NOCAP_A, false, false, true, false,
                           ISFLAG_CURSED).c_str());
        msg = simple_monster_message(this, info);
    }

    const int brand = get_weapon_brand(item);
    if (brand == SPWPN_PROTECTION)
        ac += 5;
    if (brand == SPWPN_EVASION)
        ev += 5;

    if (msg)
    {
        bool message_given = true;
        switch (brand)
        {
        case SPWPN_FLAMING:
            mpr("It bursts into flame!");
            break;
        case SPWPN_FREEZING:
            mpr("It glows with a cold blue light!");
            break;
        case SPWPN_HOLY_WRATH:
            mpr("It softly glows with a divine radiance!");
            break;
        case SPWPN_ELECTROCUTION:
            mpr("You hear the crackle of electricity.", MSGCH_SOUND);
            break;
        case SPWPN_VENOM:
            mpr("It begins to drip with poison!");
            break;
        case SPWPN_DRAINING:
            mpr("You sense an unholy aura.");
            break;
        case SPWPN_FLAME:
            mpr("It bursts into flame!");
            break;
        case SPWPN_FROST:
            mpr("It is covered in frost.");
            break;
        case SPWPN_RETURNING:
            mpr("It wiggles slightly.");
            break;
        case SPWPN_DISTORTION:
            mpr("Its appearance distorts for a moment.");
            break;
        case SPWPN_CHAOS:
            mpr("It is briefly surrounded by a scintillating aura of "
                "random colours.");
            break;
        case SPWPN_PENETRATION:
            mprf("%s %s briefly pass through it before %s manages to get a "
                 "firm grip on it.",
                 pronoun(PRONOUN_CAP_POSSESSIVE).c_str(),
                 hand_name(true).c_str(),
                 pronoun(PRONOUN_NOCAP).c_str());
            break;
        case SPWPN_REAPING:
            mpr("It is briefly surrounded by shifting shadows.");
            break;

        default:
            // A ranged weapon without special message is known to be unbranded.
            if (brand != SPWPN_NORMAL || !is_range_weapon(item))
                message_given = false;
        }

        if (message_given)
        {
            if (is_artefact(item) && !is_special_unrandom_artefact(item))
                artefact_wpn_learn_prop(item, ARTP_BRAND);
            else
                set_ident_flags(item, ISFLAG_KNOW_TYPE);
        }
    }
}

void monsters::equip_armour(item_def &item, int near)
{
    if (need_message(near))
    {
        snprintf(info, INFO_SIZE, " wears %s.",
                 item.name(DESC_NOCAP_A).c_str());
        simple_monster_message(this, info);
    }

    const equipment_type eq = get_armour_slot(item);
    if (eq != EQ_SHIELD)
    {
        ac += property( item, PARM_AC );

        const int armour_plus = item.plus;
        ASSERT(abs(armour_plus) < 20);
        if (abs(armour_plus) < 20)
            ac += armour_plus;
    }

    // Shields can affect evasion.
    ev += property( item, PARM_EVASION ) / 2;
    if (ev < 1)
        ev = 1;   // This *shouldn't* happen.
}

void monsters::equip(item_def &item, int slot, int near)
{
    switch (item.base_type)
    {
    case OBJ_WEAPONS:
    {
        bool give_msg = (slot == MSLOT_WEAPON || mons_wields_two_weapons(this));
        equip_weapon(item, near, give_msg);
        break;
    }
    case OBJ_ARMOUR:
        equip_armour(item, near);
        break;
    default:
        break;
    }
}

void monsters::unequip_weapon(item_def &item, int near, bool msg)
{
    if (msg && !need_message(near))
        msg = false;

    if (msg)
    {
        snprintf(info, INFO_SIZE, " unwields %s.",
                             item.name(DESC_NOCAP_A, false, false, true, false,
                             ISFLAG_CURSED).c_str());
        msg = simple_monster_message(this, info);
    }

    const int brand = get_weapon_brand(item);
    if (brand == SPWPN_PROTECTION)
        ac -= 5;
    if (brand == SPWPN_EVASION)
        ev -= 5;

    if (msg && brand != SPWPN_NORMAL)
    {
        bool message_given = true;
        switch (brand)
        {
        case SPWPN_FLAMING:
            mpr("It stops flaming.");
            break;

        case SPWPN_HOLY_WRATH:
            mpr("It stops glowing.");
            break;

        case SPWPN_ELECTROCUTION:
            mpr("It stops crackling.");
            break;

        case SPWPN_VENOM:
            mpr("It stops dripping with poison.");
            break;

        case SPWPN_DISTORTION:
            mpr("Its appearance distorts for a moment.");
            break;

        default:
            message_given = false;
        }
        if (message_given)
        {
            if (is_artefact(item) && !is_special_unrandom_artefact(item))
                artefact_wpn_learn_prop(item, ARTP_BRAND);
            else
                set_ident_flags(item, ISFLAG_KNOW_TYPE);
        }
    }
}

void monsters::unequip_armour(item_def &item, int near)
{
    if (need_message(near))
    {
        snprintf(info, INFO_SIZE, " takes off %s.",
                 item.name(DESC_NOCAP_A).c_str());
        simple_monster_message(this, info);
    }

    const equipment_type eq = get_armour_slot(item);
    if (eq != EQ_SHIELD)
    {
        ac -= property( item, PARM_AC );

        const int armour_plus = item.plus;
        ASSERT(abs(armour_plus) < 20);
        if (abs(armour_plus) < 20)
            ac -= armour_plus;
    }

    ev -= property( item, PARM_EVASION ) / 2;
    if (ev < 1)
        ev = 1;   // This *shouldn't* happen.
}

bool monsters::unequip(item_def &item, int slot, int near, bool force)
{
    if (!force && item.cursed())
        return (false);

    if (!force && you.can_see(this))
        set_ident_flags(item, ISFLAG_KNOW_CURSE);

    switch (item.base_type)
    {
    case OBJ_WEAPONS:
    {
        bool give_msg = (slot == MSLOT_WEAPON || mons_wields_two_weapons(this));

        unequip_weapon(item, near, give_msg);
        break;
    }
    case OBJ_ARMOUR:
        unequip_armour(item, near);
        break;

    default:
        break;
    }

    return (true);
}

void monsters::lose_pickup_energy()
{
    if (const monsterentry* entry = find_monsterentry())
    {
        const int delta = speed * entry->energy_usage.pickup_percent / 100;
        if (speed_increment > 25 && delta < speed_increment)
            speed_increment -= delta;
    }
}

void monsters::pickup_message(const item_def &item, int near)
{
    if (need_message(near))
    {
        mprf("%s picks up %s.",
             name(DESC_CAP_THE).c_str(),
             item.base_type == OBJ_GOLD ? "some gold"
                                        : item.name(DESC_NOCAP_A).c_str());
    }
}

bool monsters::pickup(item_def &item, int slot, int near, bool force_merge)
{
    ASSERT(item.is_valid());

    const monsters *other_mon = item.holding_monster();

    if (other_mon != NULL)
    {
        if (other_mon == this)
        {
            if (inv[slot] == item.index())
            {
                mprf(MSGCH_DIAGNOSTICS, "Monster %s already holding item %s.",
                     name(DESC_PLAIN, true).c_str(),
                     item.name(DESC_PLAIN, false, true).c_str());
                return (false);
            }
            else
            {
                mprf(MSGCH_DIAGNOSTICS, "Item %s thinks it's already held by "
                                        "monster %s.",
                     item.name(DESC_PLAIN, false, true).c_str(),
                     name(DESC_PLAIN, true).c_str());
            }
        }
        else if (other_mon->type == MONS_NO_MONSTER)
        {
            mprf(MSGCH_DIAGNOSTICS, "Item %s, held by dead monster, being "
                                    "picked up by monster %s.",
                 item.name(DESC_PLAIN, false, true).c_str(),
                 name(DESC_PLAIN, true).c_str());
        }
        else
        {
            mprf(MSGCH_DIAGNOSTICS, "Item %s, held by monster %s, being "
                                    "picked up by monster %s.",
                 item.name(DESC_PLAIN, false, true).c_str(),
                 other_mon->name(DESC_PLAIN, true).c_str(),
                 name(DESC_PLAIN, true).c_str());
        }
    }

    // If a monster chooses a two-handed weapon as main weapon, it will
    // first have to drop any shield it might wear.
    // (Monsters will always favour damage over protection.)
    if ((slot == MSLOT_WEAPON || slot == MSLOT_ALT_WEAPON)
        && inv[MSLOT_SHIELD] != NON_ITEM
        && hands_reqd(item, body_size()) == HANDS_TWO)
    {
        if (!drop_item(MSLOT_SHIELD, near))
            return (false);
    }

    // Similarly, monsters won't pick up shields if they're
    // wielding (or alt-wielding) a two-handed weapon.
    if (slot == MSLOT_SHIELD)
    {
        const item_def* wpn = mslot_item(MSLOT_WEAPON);
        const item_def* alt = mslot_item(MSLOT_ALT_WEAPON);
        if (wpn && hands_reqd(*wpn, body_size()) == HANDS_TWO)
            return (false);
        if (alt && hands_reqd(*alt, body_size()) == HANDS_TWO)
            return (false);
    }

    if (inv[slot] != NON_ITEM)
    {
        item_def &dest(mitm[inv[slot]]);
        if (items_stack(item, dest, force_merge))
        {
            dungeon_events.fire_position_event(
                dgn_event(DET_ITEM_PICKUP, pos(), 0, item.index(),
                          mindex()),
                pos());

            pickup_message(item, near);
            inc_mitm_item_quantity( inv[slot], item.quantity );
            merge_item_stacks(item, dest);
            destroy_item(item.index());
            equip(item, slot, near);
            lose_pickup_energy();
            return (true);
        }
        return (false);
    }

    dungeon_events.fire_position_event(
        dgn_event(DET_ITEM_PICKUP, pos(), 0, item.index(),
                  mindex()),
        pos());

    const int item_index = item.index();
    unlink_item(item_index);

    inv[slot] = item_index;

    item.set_holding_monster(mindex());

    pickup_message(item, near);
    equip(item, slot, near);
    lose_pickup_energy();
    return (true);
}

bool monsters::drop_item(int eslot, int near)
{
    if (eslot < 0 || eslot >= NUM_MONSTER_SLOTS)
        return (false);

    int item_index = inv[eslot];
    if (item_index == NON_ITEM)
        return (true);

    item_def* pitem = &mitm[item_index];

    // Unequip equipped items before dropping them; unequip() prevents
    // cursed items from being removed.
    bool was_unequipped = false;
    if (eslot == MSLOT_WEAPON || eslot == MSLOT_ARMOUR
        || eslot == MSLOT_ALT_WEAPON && mons_wields_two_weapons(this))
    {
        if (!unequip(*pitem, eslot, near))
            return (false);
        was_unequipped = true;
    }

    if (pitem->flags & ISFLAG_SUMMONED)
    {
        if (need_message(near))
        {
            mprf("%s %s as %s drops %s!",
                 pitem->name(DESC_CAP_THE).c_str(),
                 summoned_poof_msg(this, *pitem).c_str(),
                 name(DESC_NOCAP_THE).c_str(),
                 pitem->quantity > 1 ? "them" : "it");
        }

        item_was_destroyed(*pitem, mindex());
        destroy_item(item_index);
    }
    else
    {
        if (need_message(near))
        {
            mprf("%s drops %s.", name(DESC_CAP_THE).c_str(),
                 pitem->name(DESC_NOCAP_A).c_str());
        }

        if (!move_item_to_grid(&item_index, pos(), swimming()))
        {
            // Re-equip item if we somehow failed to drop it.
            if (was_unequipped)
                equip(*pitem, eslot, near);

            return (false);
        }

        if (friendly() && item_index != NON_ITEM)
        {
            // move_item_to_grid could change item_index, so
            // update pitem.
            pitem = &mitm[item_index];

            pitem->flags |= ISFLAG_DROPPED_BY_ALLY;
        }
    }

    inv[eslot] = NON_ITEM;
    return (true);
}

// We don't want monsters to pick up ammunition that cancels out with
// the launcher brand or that is identical to the launcher brand,
// the latter in hope of another monster wandering by who may want to
// use the ammo in question.
static bool _compatible_launcher_ammo_brands(item_def *launcher,
                                             const item_def *ammo)
{
    // If the monster has no ammo then there's no compatibility problems
    // to check.
    if (ammo == NULL)
        return (true);

    const int bow_brand  = get_weapon_brand(*launcher);
    const int ammo_brand = get_ammo_brand(*ammo);

    switch (ammo_brand)
    {
    case SPMSL_FLAME:
    case SPMSL_FROST:
        return (bow_brand != SPWPN_FLAME && bow_brand != SPWPN_FROST);
    case SPMSL_CHAOS:
        return (bow_brand != SPWPN_CHAOS);
    case SPMSL_REAPING:
        return (bow_brand != SPWPN_HOLY_WRATH);
    default:
        return (true);
    }
}

bool monsters::pickup_launcher(item_def &launch, int near)
{
    // Don't allow monsters to pick up launchers that would also
    // refuse to pick up the matching ammo.
    if (!_needs_ranged_attack(this))
        return (false);

    // Don't allow monsters to switch to another type of launcher
    // as that would require them to also drop their ammunition
    // and then try to find ammunition for their new launcher.
    // However, they may switch to another launcher if they're
    // out of ammo. (jpeg)
    const int mdam_rating = mons_weapon_damage_rating(launch);
    const missile_type mt = fires_ammo_type(launch);
    int eslot = -1;
    for (int i = MSLOT_WEAPON; i <= MSLOT_ALT_WEAPON; ++i)
    {
        if (const item_def *elaunch = mslot_item(static_cast<mon_inv_type>(i)))
        {
            if (!is_range_weapon(*elaunch))
                continue;

            return ((fires_ammo_type(*elaunch) == mt || !missiles())
                    && (mons_weapon_damage_rating(*elaunch) < mdam_rating
                        || mons_weapon_damage_rating(*elaunch) == mdam_rating
                           && get_weapon_brand(*elaunch) == SPWPN_NORMAL
                           && get_weapon_brand(launch) != SPWPN_NORMAL
                           && _compatible_launcher_ammo_brands(&launch,
                                                               missiles()))
                    && drop_item(i, near) && pickup(launch, i, near));
        }
        else
            eslot = i;
    }

    return (eslot == -1 ? false : pickup(launch, eslot, near));
}

static bool _is_signature_weapon(monsters *monster, const item_def &weapon)
{
    if (weapon.base_type != OBJ_WEAPONS)
        return (false);

    if (monster->type == MONS_ANGEL)
        return (weapon.sub_type == WPN_HOLY_SCOURGE);

    if (monster->type == MONS_DAEVA)
        return (weapon.sub_type == WPN_HOLY_EUDEMON_BLADE);

    // We might allow Sigmund to pick up a better scythe if he finds one...
    if (monster->type == MONS_SIGMUND)
        return (weapon.sub_type == WPN_SCYTHE);

    if (is_unrandom_artefact(weapon))
    {
        switch (weapon.special)
        {
        case UNRAND_ASMODEUS:
            return (monster->type == MONS_ASMODEUS);
        case UNRAND_DISPATER:
            return (monster->type == MONS_DISPATER);
        case UNRAND_CEREBOV:
            return (monster->type == MONS_CEREBOV);
        }
    }
    return (false);
}

static int _ego_damage_bonus(item_def &item)
{
    switch (get_weapon_brand(item))
    {
    case SPWPN_NORMAL:      return 0;
    case SPWPN_VORPAL:      // deliberate
    case SPWPN_PROTECTION:  // fall through
    case SPWPN_EVASION:     return 1;
    default:                return 2;
    }
}

static bool _item_race_matches_monster(const item_def &item, monsters *mons)
{
    return (get_equip_race(item) == ISFLAG_ELVEN
                && mons_genus(mons->type) == MONS_ELF
            || get_equip_race(item) == ISFLAG_ORCISH
                && mons_genus(mons->type) == MONS_ORC);
}

bool monsters::pickup_melee_weapon(item_def &item, int near)
{
    // Throwable weapons may be picked up as though dual-wielding.
    const bool dual_wielding = (mons_wields_two_weapons(this)
                                || is_throwable(this, item));
    if (dual_wielding && item.quantity == 1)
    {
        // If we have either weapon slot free, pick up the weapon.
        if (inv[MSLOT_WEAPON] == NON_ITEM)
            return pickup(item, MSLOT_WEAPON, near);

        if (inv[MSLOT_ALT_WEAPON] == NON_ITEM)
            return pickup(item, MSLOT_ALT_WEAPON, near);
    }

    const int new_wpn_dam = mons_weapon_damage_rating(item)
                            + _ego_damage_bonus(item);
    int eslot = -1;
    item_def *weap;

    // Monsters have two weapon slots, one of which can be a ranged, and
    // the other a melee weapon. (The exception being dual-wielders who can
    // wield two melee weapons). The weapon in MSLOT_WEAPON is the one
    // currently wielded (can be empty).

    for (int i = MSLOT_WEAPON; i <= MSLOT_ALT_WEAPON; ++i)
    {
        weap = mslot_item(static_cast<mon_inv_type>(i));

        // If the weapon is a stack of throwing weaons, the monster
        // will not use the stack as their primary melee weapon.
        if (item.quantity != 1 && i == MSLOT_WEAPON)
            continue;

        if (!weap)
        {
            // If no weapon in this slot, mark this one.
            if (eslot == -1)
                eslot = i;
        }
        else
        {
            if (is_range_weapon(*weap))
                continue;

            // Don't drop weapons specific to the monster.
            if (_is_signature_weapon(this, *weap) && !dual_wielding)
                return (false);

            // If we get here, the weapon is a melee weapon.
            // If the new weapon is better than the current one and not cursed,
            // replace it. Otherwise, give up.
            const int old_wpn_dam = mons_weapon_damage_rating(*weap)
                                    + _ego_damage_bonus(*weap);

            bool new_wpn_better = (new_wpn_dam > old_wpn_dam);
            if (new_wpn_dam == old_wpn_dam)
            {
                // Use shopping value as a crude estimate of resistances etc.
                // XXX: This is not really logical as many properties don't
                //      apply to monsters (e.g. levitation, blink, berserk).
                // For simplicity, don't apply this check to secondary weapons
                // for dual wielding monsters.
                int oldval = item_value(*weap, true);
                int newval = item_value(item, true);

                // Vastly prefer matching racial type.
                if (_item_race_matches_monster(*weap, this))
                    oldval *= 2;
                if (_item_race_matches_monster(item, this))
                    newval *= 2;

                if (newval > oldval)
                    new_wpn_better = true;
            }

            if (new_wpn_better && !weap->cursed())
            {
                if (!dual_wielding
                    || i == MSLOT_WEAPON
                    || old_wpn_dam
                       < mons_weapon_damage_rating(*mslot_item(MSLOT_WEAPON))
                         + _ego_damage_bonus(*mslot_item(MSLOT_WEAPON)))
                {
                    eslot = i;
                    if (!dual_wielding)
                        break;
                }
            }
            else if (!dual_wielding)
            {
                // We've got a good melee weapon, that's enough.
               return (false);
            }
        }
    }

    // No slot found to place this item.
    if (eslot == -1)
        return (false);

    // Current item cannot be dropped.
    if (inv[eslot] != NON_ITEM && !drop_item(eslot, near))
        return (false);

    return (pickup(item, eslot, near));
}

// Arbitrary damage adjustment for quantity of missiles. So sue me.
static int _q_adj_damage(int damage, int qty)
{
    return (damage * std::min(qty, 8));
}

bool monsters::pickup_throwable_weapon(item_def &item, int near)
{
    const mon_inv_type slot = item_to_mslot(item);

    // If it's a melee weapon then pickup_melee_weapon() already rejected
    // it, even though it can also be thrown.
    if (slot == MSLOT_WEAPON)
        return (false);

    ASSERT(slot == MSLOT_MISSILE);

    // Spellcasters shouldn't bother with missiles.
    if (mons_has_ranged_spell(this, true, false))
        return (false);

    // If occupied, don't pick up a throwable weapons if it would just
    // stack with an existing one. (Upgrading is possible.)
    if (mslot_item(slot)
        && (mons_is_wandering(this) || friendly() && foe == MHITYOU)
        && pickup(item, slot, near, true))
    {
        return (true);
    }

    item_def *launch = NULL;
    const int exist_missile = mons_pick_best_missile(this, &launch, true);
    if (exist_missile == NON_ITEM
        || (_q_adj_damage(mons_missile_damage(this, launch,
                                              &mitm[exist_missile]),
                          mitm[exist_missile].quantity)
            < _q_adj_damage(mons_thrown_weapon_damage(&item), item.quantity)))
    {
        if (inv[slot] != NON_ITEM && !drop_item(slot, near))
            return (false);
        return pickup(item, slot, near);
    }
    return (false);
}

bool monsters::wants_weapon(const item_def &weap) const
{
    if (!could_wield(weap))
       return (false);

    // Blademasters and master archers like their starting weapon and
    // don't want another, thank you.
    if (type == MONS_DEEP_ELF_BLADEMASTER
        || type == MONS_DEEP_ELF_MASTER_ARCHER)
    {
        return (false);
    }

    // Monsters capable of dual-wielding will always prefer two weapons
    // to a single two-handed one, however strong.
    if (mons_wields_two_weapons(this)
        && hands_reqd(weap, body_size()) == HANDS_TWO)
    {
        return (false);
    }

    // Nobody picks up giant clubs. Starting equipment is okay, of course.
    if (weap.sub_type == WPN_GIANT_CLUB
        || weap.sub_type == WPN_GIANT_SPIKED_CLUB)
    {
        return (false);
    }

    return (true);
}

bool monsters::wants_armour(const item_def &item) const
{
    // Monsters that are capable of dual wielding won't pick up shields.
    // Neither will monsters that are already wielding a two-hander.
    if (is_shield(item)
        && (mons_wields_two_weapons(this)
            || mslot_item(MSLOT_WEAPON)
               && hands_reqd(*mslot_item(MSLOT_WEAPON), body_size())
                      == HANDS_TWO))
    {
        return (false);
    }

    // Returns whether this armour is the monster's size.
    return (check_armour_size(item, body_size()));
}

bool monsters::pickup_armour(item_def &item, int near, bool force)
{
    ASSERT(item.base_type == OBJ_ARMOUR);

    if (!force && !wants_armour(item))
        return (false);

    equipment_type eq = EQ_NONE;

    // HACK to allow nagas/centaurs to wear bardings. (jpeg)
    switch (item.sub_type)
    {
    case ARM_NAGA_BARDING:
        if (::mons_genus(type) == MONS_NAGA)
            eq = EQ_BODY_ARMOUR;
        break;
    case ARM_CENTAUR_BARDING:
        if (::mons_species(type) == MONS_CENTAUR
            || ::mons_species(type) == MONS_YAKTAUR)
        {
            eq = EQ_BODY_ARMOUR;
        }
        break;
    // And another hack or two...
    case ARM_WIZARD_HAT:
        if (type == MONS_GASTRONOK)
            eq = EQ_BODY_ARMOUR;
        break;
    case ARM_CLOAK:
        if (type == MONS_MAURICE
            || type == MONS_NIKOLA
            || type == MONS_CRAZY_YIUF)
        {
            eq = EQ_BODY_ARMOUR;
        }
        break;
    case ARM_GLOVES:
        if (type == MONS_NIKOLA)
            eq = EQ_SHIELD;
        break;
    default:
        eq = get_armour_slot(item);
    }

    // Bardings are only wearable by the appropriate monster.
    if (eq == EQ_NONE)
        return (false);

    // XXX: Monsters can only equip body armour and shields (as of 0.4).
    if (!force && eq != EQ_BODY_ARMOUR && eq != EQ_SHIELD)
        return (false);

    const mon_inv_type mslot = equip_slot_to_mslot(eq);
    if (mslot == NUM_MONSTER_SLOTS)
        return (false);

    int newAC = item.armour_rating();

    // No armour yet -> get this one.
    if (!mslot_item(mslot) && newAC > 0)
        return pickup(item, mslot, near);

    // Very simplistic armour evaluation (AC comparison).
    if (const item_def *existing_armour = slot_item(eq))
    {
        if (!force)
        {
            int oldAC = existing_armour->armour_rating();
            if (oldAC > newAC)
                return (false);

            if (oldAC == newAC)
            {
                // Use shopping value as a crude estimate of resistances etc.
                // XXX: This is not really logical as many properties don't
                //      apply to monsters (e.g. levitation, blink, berserk).
                int oldval = item_value(*existing_armour, true);
                int newval = item_value(item, true);

                // Vastly prefer matching racial type.
                if (_item_race_matches_monster(*existing_armour, this))
                    oldval *= 2;
                if (_item_race_matches_monster(item, this))
                    newval *= 2;

                if (oldval >= newval)
                    return (false);
            }
        }

        if (!drop_item(mslot, near))
            return (false);
    }

    return (pickup(item, mslot, near));
}

bool monsters::pickup_weapon(item_def &item, int near, bool force)
{
    if (!force && !wants_weapon(item))
        return (false);

    // Weapon pickup involves:
    // - If we have no weapons, always pick this up.
    // - If this is a melee weapon and we already have a melee weapon, pick
    //   it up if it is superior to the one we're carrying (and drop the
    //   one we have).
    // - If it is a ranged weapon, and we already have a ranged weapon,
    //   pick it up if it is better than the one we have.
    // - If it is a throwable weapon, and we're carrying no missiles (or our
    //   missiles are the same type), pick it up.

    if (is_range_weapon(item))
        return (pickup_launcher(item, near));

    if (pickup_melee_weapon(item, near))
        return (true);

    return (can_use_missile(item) && pickup_throwable_weapon(item, near));
}

bool monsters::pickup_missile(item_def &item, int near, bool force)
{
    const item_def *miss = missiles();

    if (!force)
    {
        if (item.sub_type == MI_THROWING_NET)
        {
            // Monster may not pick up trapping net.
            if (this->caught() && item_is_stationary(item))
                return (false);
        }
        else // None of these exceptions hold for throwing nets.
        {
            // Spellcasters should not waste time with ammunition.
            // Neither summons nor hostile enchantments are counted for
            // this purpose.
            if (mons_has_ranged_spell(this, true, false))
                return (false);

            // Monsters in a fight will only pick up missiles if doing so
            // is worthwhile.
            if (!mons_is_wandering(this)
                && (!friendly() || foe != MHITYOU)
                && (item.quantity < 5 || miss && miss->quantity >= 7))
            {
                return (false);
            }
        }
    }

    if (miss && items_stack(*miss, item))
        return (pickup(item, MSLOT_MISSILE, near));

    if (!force && !can_use_missile(item))
        return (false);

    if (miss)
    {
        item_def *launch;
        for (int i = MSLOT_WEAPON; i <= MSLOT_ALT_WEAPON; ++i)
        {
            launch = mslot_item(static_cast<mon_inv_type>(i));
            if (launch)
            {
                const int item_brand = get_ammo_brand(item);
                // If this ammunition is better, drop the old ones.
                // Don't upgrade to ammunition whose brand cancels the
                // launcher brand or doesn't improve it further.
                if (fires_ammo_type(*launch) == item.sub_type
                    && (fires_ammo_type(*launch) != miss->sub_type
                        || item.plus > miss->plus
                           && get_ammo_brand(*miss) == item_brand
                        || item.plus >= miss->plus
                           && get_ammo_brand(*miss) == SPMSL_NORMAL
                           && item_brand != SPMSL_NORMAL
                           &&_compatible_launcher_ammo_brands(launch, miss)))
                {
                    if (!drop_item(MSLOT_MISSILE, near))
                        return (false);
                    break;
                }
            }
        }

        // Darts don't absolutely need a launcher - still allow upgrading.
        if (item.sub_type == miss->sub_type
            && item.sub_type == MI_DART
            && (item.plus > miss->plus
                || item.plus == miss->plus
                   && get_ammo_brand(*miss) == SPMSL_NORMAL
                   && get_ammo_brand(item) != SPMSL_NORMAL))
        {
            if (!drop_item(MSLOT_MISSILE, near))
                return (false);
        }
    }

    return pickup(item, MSLOT_MISSILE, near);
}

bool monsters::pickup_wand(item_def &item, int near)
{
    // Don't pick up empty wands.
    if (item.plus == 0)
        return (false);

    // Only low-HD monsters bother with wands.
    if (hit_dice >= 14)
        return (false);

    // Holy monsters and worshippers of good gods won't pick up evil
    // wands.
    if ((is_holy() || is_good_god(god)) && is_evil_item(item))
        return (false);

    // If a monster already has a charged wand, don't bother.
    // Otherwise, replace with a charged one.
    if (item_def *wand = mslot_item(MSLOT_WAND))
    {
        if (wand->plus > 0)
            return (false);

        if (!drop_item(MSLOT_WAND, near))
            return (false);
    }

    return (pickup(item, MSLOT_WAND, near));
}

bool monsters::pickup_scroll(item_def &item, int near)
{
    if (item.sub_type != SCR_TELEPORTATION
        && item.sub_type != SCR_BLINKING
        && item.sub_type != SCR_SUMMONING)
    {
        return (false);
    }

    // Holy monsters and worshippers of good gods won't pick up evil
    // scrolls.
    if ((is_holy() || is_good_god(god)) && is_evil_item(item))
        return (false);

    return (pickup(item, MSLOT_SCROLL, near));
}

bool monsters::pickup_potion(item_def &item, int near)
{
    // Only allow monsters to pick up potions if they can actually use
    // them.
    const potion_type ptype = static_cast<potion_type>(item.sub_type);

    if (!can_drink_potion(ptype))
        return (false);

    return (pickup(item, MSLOT_POTION, near));
}

bool monsters::pickup_gold(item_def &item, int near)
{
    return (pickup(item, MSLOT_GOLD, near));
}

bool monsters::pickup_misc(item_def &item, int near)
{
    // Never pick up runes.
    if (item.base_type == OBJ_MISCELLANY && item.sub_type == MISC_RUNE_OF_ZOT)
        return (false);

    // Holy monsters and worshippers of good gods won't pick up evil
    // miscellaneous items.
    if ((is_holy() || is_good_god(god)) && is_evil_item(item))
        return (false);

    return (pickup(item, MSLOT_MISCELLANY, near));
}

// Eaten items are handled elsewhere, in _handle_pickup() in mon-stuff.cc.
bool monsters::pickup_item(item_def &item, int near, bool force)
{
    // Equipping stuff can be forced when initially equipping monsters.
    if (!force)
    {
        // If a monster isn't otherwise occupied (has a foe, is fleeing, etc.)
        // it is considered wandering.
        bool wandering = (mons_is_wandering(this)
                          || friendly() && foe == MHITYOU);
        const int itype = item.base_type;

        // Weak(ened) monsters won't stop to pick up things as long as they
        // feel unsafe.
        if (!wandering && (hit_points * 10 < max_hit_points || hit_points < 10)
            && mon_enemies_around(this))
        {
            return (false);
        }

        if (friendly())
        {
            // Never pick up gold or misc. items, it'd only annoy the player.
            if (itype == OBJ_MISCELLANY || itype == OBJ_GOLD)
                return (false);

            // Depending on the friendly pickup toggle, your allies may not
            // pick up anything, or only stuff dropped by (other) allies.
            if (you.friendly_pickup == FRIENDLY_PICKUP_NONE
                || you.friendly_pickup == FRIENDLY_PICKUP_FRIEND
                   && !testbits(item.flags, ISFLAG_DROPPED_BY_ALLY)
                || you.friendly_pickup == FRIENDLY_PICKUP_PLAYER
                   && !(item.flags & (ISFLAG_DROPPED | ISFLAG_THROWN
                                        | ISFLAG_DROPPED_BY_ALLY)))
            {
                return (false);
            }
        }

        if (!wandering)
        {
            // These are not important enough for pickup when
            // seeking, fleeing etc.
            if (itype == OBJ_ARMOUR || itype == OBJ_CORPSES
                || itype == OBJ_MISCELLANY || itype == OBJ_GOLD)
            {
                return (false);
            }

            if (itype == OBJ_WEAPONS || itype == OBJ_MISSILES)
            {
                // Fleeing monsters only pick up emergency equipment.
                if (mons_is_fleeing(this))
                    return (false);

                // While occupied, hostile monsters won't pick up items
                // dropped or thrown by you. (You might have done that to
                // distract them.)
                if (!friendly()
                    && (testbits(item.flags, ISFLAG_DROPPED)
                        || testbits(item.flags, ISFLAG_THROWN)))
                {
                    return (false);
                }
            }
        }
    }

    switch (item.base_type)
    {
    // Pickup some stuff only if WANDERING.
    case OBJ_ARMOUR:
        return pickup_armour(item, near, force);
    case OBJ_MISCELLANY:
        return pickup_misc(item, near);
    case OBJ_GOLD:
        return pickup_gold(item, near);
    // Fleeing monsters won't pick up these.
    // Hostiles won't pick them up if they were ever dropped/thrown by you.
    case OBJ_WEAPONS:
        return pickup_weapon(item, near, force);
    case OBJ_MISSILES:
        return pickup_missile(item, near, force);
    // Other types can always be picked up
    // (barring other checks depending on subtype, of course).
    case OBJ_WANDS:
        return pickup_wand(item, near);
    case OBJ_SCROLLS:
        return pickup_scroll(item, near);
    case OBJ_POTIONS:
        return pickup_potion(item, near);
    case OBJ_BOOKS:
        if (force)
            return pickup_misc(item, near);
        // else fall through
    default:
        return (false);
    }
}

bool monsters::need_message(int &near) const
{
    return (near != -1 ? near
                       : (near = observable()));
}

void monsters::swap_weapons(int near)
{
    item_def *weap = mslot_item(MSLOT_WEAPON);
    item_def *alt  = mslot_item(MSLOT_ALT_WEAPON);

    if (weap && !unequip(*weap, MSLOT_WEAPON, near))
    {
        // Item was cursed.
        return;
    }

    swap_slots(MSLOT_WEAPON, MSLOT_ALT_WEAPON);

    if (alt)
        equip(*alt, MSLOT_WEAPON, near);

    // Monsters can swap weapons really fast. :-)
    if ((weap || alt) && speed_increment >= 2)
    {
        if (const monsterentry *entry = find_monsterentry())
            speed_increment -= div_rand_round(entry->energy_usage.attack, 5);
    }
}

void monsters::wield_melee_weapon(int near)
{
    const item_def *weap = mslot_item(MSLOT_WEAPON);
    if (!weap || (!weap->cursed() && is_range_weapon(*weap)))
    {
        const item_def *alt = mslot_item(MSLOT_ALT_WEAPON);

        // Switch to the alternate weapon if it's not a ranged weapon, too,
        // or switch away from our main weapon if it's a ranged weapon.
        //
        // Don't switch to alt weapon if it's a stack of throwing weapons.
        if (alt && !is_range_weapon(*alt) && alt->quantity == 1
            || weap && !alt && type != MONS_STATUE)
        {
            swap_weapons(near);
        }
    }
}

item_def *monsters::slot_item(equipment_type eq)
{
    return (mslot_item(equip_slot_to_mslot(eq)));
}

item_def *monsters::mslot_item(mon_inv_type mslot) const
{
    const int mi = (mslot == NUM_MONSTER_SLOTS) ? NON_ITEM : inv[mslot];
    return (mi == NON_ITEM ? NULL : &mitm[mi]);
}

item_def *monsters::shield()
{
    return (mslot_item(MSLOT_SHIELD));
}

bool monsters::is_named() const
{
    return (!mname.empty() || mons_is_unique(type));
}

bool monsters::has_base_name() const
{
    // Any non-ghost, non-Pandemonium demon that has an explicitly set
    // name has a base name.
    return (!mname.empty() && !ghost.get());
}

static const char *ugly_colour_names[] = {
    "red", "brown", "green", "cyan", "purple", "white"
};

static std::string _ugly_thing_colour_name(const monsters *mon)
{
    int colour_offset = -1;

    if (mon->type == MONS_UGLY_THING || mon->type == MONS_VERY_UGLY_THING)
        colour_offset = ugly_thing_colour_offset(mon->colour);

    if (colour_offset == -1)
        return ("buggy");

    return (ugly_colour_names[colour_offset]);
}

static std::string _invalid_monster_str(monster_type type)
{
    std::string str = "INVALID MONSTER ";

    switch (type)
    {
    case NUM_MONSTERS:
        return (str + "NUM_MONSTERS");
    case MONS_NO_MONSTER:
        return (str + "MONS_NO_MONSTER");
    case MONS_PLAYER:
        return (str + "MONS_PLAYER");
    case RANDOM_DRACONIAN:
        return (str + "RANDOM_DRACONIAN");
    case RANDOM_BASE_DRACONIAN:
        return (str + "RANDOM_BASE_DRACONIAN");
    case RANDOM_NONBASE_DRACONIAN:
        return (str + "RANDOM_NONBASE_DRACONIAN");
    case WANDERING_MONSTER:
        return (str + "WANDERING_MONSTER");
    default:
        break;
    }

    str += make_stringf("#%d", (int) type);

    if (type < 0)
        return (str);

    if (type > NUM_MONSTERS)
    {
        str += make_stringf(" (NUM_MONSTERS + %d)",
                            int (NUM_MONSTERS - type));
        return (str);
    }

    int          i;
    monster_type new_type;
    for (i = 0; true; i++)
    {
        new_type = (monster_type) ( ((int) type) - i);

        if (invalid_monster_type(new_type))
            continue;
        break;
    }
    str += make_stringf(" (%s + %d)",
                        mons_type_name(new_type, DESC_PLAIN).c_str(),
                        i);

    return (str);
}

static std::string _str_monam(const monsters& mon, description_level_type desc,
                              bool force_seen)
{
    monster_type type = mon.type;
    if (!crawl_state.arena && you.misled())
        type = mon.get_mislead_type();

    if (type == MONS_NO_MONSTER)
        return ("DEAD MONSTER");
    else if (invalid_monster_type(type) && type != MONS_PROGRAM_BUG)
        return _invalid_monster_str(type);

    const bool arena_submerged = crawl_state.arena && !force_seen
                                     && mon.submerged();

    // Handle non-visible case first.
    if (!force_seen && !mon.observable() && !arena_submerged)
    {
        switch (desc)
        {
        case DESC_CAP_THE: case DESC_CAP_A:
            return ("It");
        case DESC_NOCAP_THE: case DESC_NOCAP_A: case DESC_PLAIN:
            return ("it");
        default:
            return ("it (buggy)");
        }
    }

    // Assumed visible from now on.

    // Various special cases:
    // non-gold mimics, dancing weapons, ghosts, Pan demons
    if (mons_is_mimic(type))
        return (get_mimic_item(&mon).name(desc));

    if (type == MONS_DANCING_WEAPON && mon.inv[MSLOT_WEAPON] != NON_ITEM)
    {
        unsigned long ignore_flags = ISFLAG_KNOW_CURSE | ISFLAG_KNOW_PLUSES;
        bool          use_inscrip  = true;

        if (desc == DESC_BASENAME || desc == DESC_QUALNAME
            || desc == DESC_DBNAME)
        {
            use_inscrip = false;
        }

        const item_def& item = mitm[mon.inv[MSLOT_WEAPON]];
        return (item.name(desc, false, false, use_inscrip, false,
                          ignore_flags));
    }

    if (desc == DESC_DBNAME)
        return (get_monster_data(type)->name);

    if (type == MONS_PLAYER_GHOST)
    {
        if (mon.is_summoned())
            return (apostrophise(mon.mname) + " illusion");
        else
            return (apostrophise(mon.mname) + " ghost");
    }

    // Some monsters might want the name of a different creature.
    monster_type nametype = type;

    // Tack on other prefixes.
    switch (type)
    {
    case MONS_ZOMBIE_SMALL:     case MONS_ZOMBIE_LARGE:
    case MONS_SKELETON_SMALL:   case MONS_SKELETON_LARGE:
    case MONS_SIMULACRUM_SMALL: case MONS_SIMULACRUM_LARGE:
    case MONS_SPECTRAL_THING:
        nametype = mon.base_monster;
        break;

    default:
        break;
    }

    // If the monster has an explicit name, return that, handling it like
    // a unique's name.  Special handling for named hydras.
    if (desc != DESC_BASENAME && !mon.mname.empty()
        && mons_genus(nametype) != MONS_HYDRA
        && !testbits(mon.flags, MF_NAME_DESCRIPTOR))
    {
        return (mon.mname);
    }

    std::string result;

    // Start building the name string.

    // Start with the prefix.
    // (Uniques don't get this, because their names are proper nouns.)
    if (!mons_is_unique(nametype)
        && ((mon.mname.empty() || testbits(mon.flags, MF_NAME_DESCRIPTOR))
            || mons_genus(nametype) == MONS_HYDRA))
    {
        const bool use_your = mon.friendly();
        switch (desc)
        {
        case DESC_CAP_THE:
            result = (use_your ? "Your " : "The ");
            break;
        case DESC_NOCAP_THE:
            result = (use_your ? "your " : "the ");
            break;
        case DESC_CAP_A:
            if (mon.mname.empty() || (testbits(mon.flags, MF_NAME_DESCRIPTOR)
                && !testbits(mon.flags, MF_NAME_DEFINITE)))
                result = "A ";
            else
                result = "The ";
            break;
        case DESC_NOCAP_A:
            if (mon.mname.empty() || (testbits(mon.flags, MF_NAME_DESCRIPTOR)
                && !testbits(mon.flags, MF_NAME_DEFINITE)))
                result = "a ";
            else
                result = "the ";
            break;
        case DESC_PLAIN:
        default:
            break;
        }
    }

    if (arena_submerged)
        result += "submerged ";

    // Tack on other prefixes.
    switch (type)
    {
    case MONS_UGLY_THING:
    case MONS_VERY_UGLY_THING:
        result += _ugly_thing_colour_name(&mon) + " ";
        break;

    case MONS_SPECTRAL_THING:
        result += "spectral ";
        break;

    case MONS_DRACONIAN_CALLER:
    case MONS_DRACONIAN_MONK:
    case MONS_DRACONIAN_ZEALOT:
    case MONS_DRACONIAN_SHIFTER:
    case MONS_DRACONIAN_ANNIHILATOR:
    case MONS_DRACONIAN_KNIGHT:
    case MONS_DRACONIAN_SCORCHER:
        if (mon.base_monster != MONS_NO_MONSTER) // database search
            result += draconian_colour_name(mon.base_monster) + " ";
        break;

    default:
        break;
    }

    if (type == MONS_SLIME_CREATURE && desc != DESC_DBNAME)
    {
        ASSERT(mon.number <= 5);
        const char* cardinals[] = {"buggy ", "", "large ", "very large ",
                                   "enormous ", "titanic "};
        result += cardinals[mon.number];
    }

    if (type == MONS_BALLISTOMYCETE && desc != DESC_DBNAME)
        result += mon.number ? "active " : "";

    // Done here to cover cases of undead versions of hydras.
    if (mons_species(nametype) == MONS_HYDRA
        && mon.number > 0 && desc != DESC_DBNAME)
    {
        if (nametype == MONS_LERNAEAN_HYDRA)
            result += "the ";

        if (mon.number < 11)
        {
            const char* cardinals[] = {"one", "two", "three", "four", "five",
                                       "six", "seven", "eight", "nine", "ten"};
            result += cardinals[mon.number - 1];
        }
        else
            result += make_stringf("%d", mon.number);

        result += "-headed ";
    }

    if (!mon.mname.empty())
        result += mon.mname;
    else if (nametype == MONS_LERNAEAN_HYDRA)
        result += "Lernaean hydra";
    else
    {
        // Add the base name.
        if (invalid_monster_type(nametype) && nametype != MONS_PROGRAM_BUG)
            result += _invalid_monster_str(nametype);
        else
            result += get_monster_data(nametype)->name;
    }

    // Add suffixes.
    switch (type)
    {
    case MONS_ZOMBIE_SMALL:
    case MONS_ZOMBIE_LARGE:
        result += " zombie";
        break;
    case MONS_SKELETON_SMALL:
    case MONS_SKELETON_LARGE:
        result += " skeleton";
        break;
    case MONS_SIMULACRUM_SMALL:
    case MONS_SIMULACRUM_LARGE:
        result += " simulacrum";
        break;
    default:
        break;
    }

    // Vowel fix: Change 'a orc' to 'an orc'.
    if (result.length() >= 3
        && (result[0] == 'a' || result[0] == 'A')
        && result[1] == ' '
        && is_vowel(result[2])
        // XXX: Hack
        && !starts_with(&result[2], "one-"))
    {
        result.insert(1, "n");
    }

    if (mons_is_unique(type) && starts_with(result, "the "))
    {
        switch (desc)
        {
        case DESC_CAP_THE:
        case DESC_CAP_A:
            result = upcase_first(result);
            break;

        default:
            break;
        }
    }

    if ((mon.flags & MF_KNOWN_MIMIC) && mon.is_shapeshifter())
    {
        // If momentarily in original form, don't display "shaped
        // shifter".
        if (mons_genus(type) != MONS_SHAPESHIFTER)
            result += " shaped shifter";
    }

    // All done.
    return (result);
}

std::string monsters::name(description_level_type desc, bool force_vis) const
{
    if (desc == DESC_NONE)
        return ("");

    const bool possessive =
        (desc == DESC_NOCAP_YOUR || desc == DESC_NOCAP_ITS);

    if (possessive)
        desc = DESC_NOCAP_THE;

    std::string monnam;
    if ((flags & MF_NAME_MASK) && (force_vis || observable())
        || crawl_state.arena && mons_class_is_zombified(type))
    {
        monnam = full_name(desc);
    }
    else
        monnam = _str_monam(*this, desc, force_vis);

    return (possessive ? apostrophise(monnam) : monnam);
}

std::string monsters::base_name(description_level_type desc, bool force_vis)
    const
{
    if (desc == DESC_NONE)
        return ("");

    if (ghost.get() || mons_is_unique(type))
        return (name(desc, force_vis));
    else
    {
        unwind_var<std::string> tmname(
            const_cast<monsters*>(this)->mname, "");
        return (name(desc, force_vis));
    }
}

std::string monsters::full_name(description_level_type desc,
                                bool use_comma) const
{
    if (desc == DESC_NONE)
        return ("");

    std::string title = _str_monam(*this, desc, true);

    const unsigned long flag = flags & MF_NAME_MASK;

    if (flag == MF_NAME_REPLACE && !testbits(flags, MF_NAME_DESCRIPTOR))
    {
        switch(desc)
        {
        case DESC_CAP_THE:
        case DESC_CAP_A:
        case DESC_CAP_YOUR:
            title = uppercase_first(title);
            break;

        default:
            break;
        }
    }

    int _type = mons_is_zombified(this) ? base_monster : type;
    if (!crawl_state.arena && you.misled())
        _type = get_mislead_type();

    if (mons_genus(_type) == MONS_HYDRA && flag == 0)
        return (title);

    if (has_base_name())
    {
        if (flag == MF_NAME_SUFFIX)
        {
            title  = base_name(desc, true);
            title += " ";
            title += mname;
        }
        else if (flag == MF_NAME_ADJECTIVE)
        {
            title += " ";
            title += base_name(DESC_PLAIN, true);
        }
        else if (flag == MF_NAME_REPLACE)
            ;
        else
        {
            if (use_comma)
                title += ",";
            title += " ";
            title += base_name(DESC_NOCAP_THE, true);
        }
    }

    if (flag == MF_NAME_ADJECTIVE)
        title = apply_description(desc, title);

    return (title);
}

std::string monsters::pronoun(pronoun_type pro, bool force_visible) const
{
    return (mons_pronoun(static_cast<monster_type>(type), pro,
                         force_visible || you.can_see(this)));
}

std::string monsters::conj_verb(const std::string &verb) const
{
    if (!verb.empty() && verb[0] == '!')
        return (verb.substr(1));

    if (verb == "are")
        return ("is");

    if (ends_with(verb, "f") || ends_with(verb, "fe")
        || ends_with(verb, "y"))
    {
        return (verb + "s");
    }

    return (pluralise(verb));
}

std::string monsters::hand_name(bool plural, bool *can_plural) const
{
    bool _can_plural;
    if (can_plural == NULL)
        can_plural = &_can_plural;
    *can_plural = true;

    std::string str;
    char        ch = mons_char(type);

    const bool rand = (type == MONS_CHAOS_SPAWN);

    switch (get_mon_shape(this))
    {
    case MON_SHAPE_CENTAUR:
    case MON_SHAPE_NAGA:
        // Defaults to "hand"
        break;
    case MON_SHAPE_HUMANOID:
    case MON_SHAPE_HUMANOID_WINGED:
    case MON_SHAPE_HUMANOID_TAILED:
    case MON_SHAPE_HUMANOID_WINGED_TAILED:
        if (ch == 'T' || ch == 'd' || ch == 'n' || mons_is_demon(type))
            str = "claw";
        break;

    case MON_SHAPE_QUADRUPED:
    case MON_SHAPE_QUADRUPED_TAILLESS:
    case MON_SHAPE_QUADRUPED_WINGED:
    case MON_SHAPE_ARACHNID:
        if (type == MONS_SCORPION || rand && one_chance_in(4))
            str = "pincer";
        else
        {
            str = "front ";
            return (str + foot_name(plural, can_plural));
        }
        break;

    case MON_SHAPE_BLOB:
    case MON_SHAPE_SNAKE:
    case MON_SHAPE_FISH:
        return foot_name(plural, can_plural);

    case MON_SHAPE_BAT:
        str = "wing";
        break;

    case MON_SHAPE_INSECT:
    case MON_SHAPE_INSECT_WINGED:
    case MON_SHAPE_CENTIPEDE:
        str = "antenna";
        break;

    case MON_SHAPE_SNAIL:
        str = "eye-stalk";
        break;

    case MON_SHAPE_PLANT:
        str = "leaf";
        break;

    case MON_SHAPE_MISC:
        if (ch == 'x' || ch == 'X' || rand)
        {
            str = "tentacle";
            break;
        }
        // Deliberate fallthrough.
    case MON_SHAPE_FUNGUS:
        str         = "body";
        *can_plural = false;
        break;

    case MON_SHAPE_ORB:
        switch (type)
        {
            case MONS_GIANT_SPORE:
                str = "rhizome";
                break;

            case MONS_GIANT_EYEBALL:
            case MONS_EYE_OF_DRAINING:
            case MONS_SHINING_EYE:
            case MONS_EYE_OF_DEVASTATION:
            case MONS_GOLDEN_EYE:
                *can_plural = false;
                // Deliberate fallthrough.
            case MONS_GREAT_ORB_OF_EYES:
                str = "pupil";
                break;

            case MONS_GIANT_ORANGE_BRAIN:
            default:
                if (rand)
                    str = "rhizome";
                else
                {
                    str        = "body";
                    *can_plural = false;
                }
                break;
        }
    }

   if (str.empty())
   {
       // Reduce the chance of a random-shaped monster having hands.
       if (rand && coinflip())
           return (hand_name(plural, can_plural));

       str = "hand";
   }

   if (plural && *can_plural)
       str = pluralise(str);

   return (str);
}

std::string monsters::foot_name(bool plural, bool *can_plural) const
{
    bool _can_plural;
    if (can_plural == NULL)
        can_plural = &_can_plural;
    *can_plural = true;

    std::string str;
    char        ch = mons_char(type);

    const bool rand = (type == MONS_CHAOS_SPAWN);

    switch (get_mon_shape(this))
    {
    case MON_SHAPE_INSECT:
    case MON_SHAPE_INSECT_WINGED:
    case MON_SHAPE_ARACHNID:
    case MON_SHAPE_CENTIPEDE:
        str = "leg";
        break;

    case MON_SHAPE_HUMANOID:
    case MON_SHAPE_HUMANOID_WINGED:
    case MON_SHAPE_HUMANOID_TAILED:
    case MON_SHAPE_HUMANOID_WINGED_TAILED:
        if (type == MONS_MINOTAUR)
            str = "hoof";
        else if (swimming()
                 && (type == MONS_MERFOLK || mons_genus(type) == MONS_MERMAID))
        {
            str         = "tail";
            *can_plural = false;
        }
        break;

    case MON_SHAPE_CENTAUR:
        str = "hoof";
        break;

    case MON_SHAPE_QUADRUPED:
    case MON_SHAPE_QUADRUPED_TAILLESS:
    case MON_SHAPE_QUADRUPED_WINGED:
        if (rand)
        {
            const char* feet[] = {"paw", "talon", "hoof"};
            str = RANDOM_ELEMENT(feet);
        }
        else if (ch == 'h')
            str = "paw";
        else if (ch == 'l' || ch == 'D')
            str = "talon";
        else if (type == MONS_YAK || type == MONS_DEATH_YAK)
            str = "hoof";
        else if (ch == 'H')
        {
            if (type == MONS_MANTICORE || type == MONS_SPHINX)
                str = "paw";
            else
                str = "talon";
        }
        break;

    case MON_SHAPE_BAT:
        str = "claw";
        break;

    case MON_SHAPE_SNAKE:
    case MON_SHAPE_FISH:
        str         = "tail";
        *can_plural = false;
        break;

    case MON_SHAPE_PLANT:
        str = "root";
        break;

    case MON_SHAPE_FUNGUS:
        str         = "stem";
        *can_plural = false;
        break;

    case MON_SHAPE_BLOB:
        str = "pseudopod";
        break;

    case MON_SHAPE_MISC:
        if (ch == 'x' || ch == 'X' || rand)
        {
            str = "tentacle";
            break;
        }
        // Deliberate fallthrough.
    case MON_SHAPE_SNAIL:
    case MON_SHAPE_NAGA:
    case MON_SHAPE_ORB:
        str         = "underside";
        *can_plural = false;
        break;
    }

   if (str.empty())
   {
       // Reduce the chance of a random-shaped monster having feet.
       if (rand && coinflip())
           return (foot_name(plural, can_plural));

       return (plural ? "feet" : "foot");
   }

   if (plural && *can_plural)
       str = pluralise(str);

   return (str);
}

std::string monsters::arm_name(bool plural, bool *can_plural) const
{
    mon_body_shape shape = get_mon_shape(this);

    if (shape > MON_SHAPE_NAGA)
        return hand_name(plural, can_plural);

    if (can_plural != NULL)
        *can_plural = true;

    std::string str;
    switch (mons_genus(type))
    {
    case MONS_NAGA:
    case MONS_DRACONIAN: str = "scaled arm"; break;

    case MONS_MUMMY: str = "bandaged wrapped arm"; break;

    case MONS_SKELETAL_WARRIOR:
    case MONS_LICH:  str = "bony arm"; break;

    default: str = "arm"; break;
    }

   if (plural)
       str = pluralise(str);

   return (str);
}

monster_type monsters::id() const
{
    return (type);
}

int monsters::mindex() const
{
    return (this - menv.buffer());
}

int monsters::get_experience_level() const
{
    return (hit_dice);
}

void monsters::moveto(const coord_def& c)
{
    if (c != pos() && in_bounds(pos()))
        mons_clear_trapping_net(this);

    set_position(c);
}

bool monsters::fumbles_attack(bool verbose)
{
    if (floundering() && one_chance_in(4))
    {
        if (verbose)
        {
            if (you.can_see(this))
            {
                mprf("%s splashes around in the water.",
                     this->name(DESC_CAP_THE).c_str());
            }
            else if (player_can_hear(pos()))
                mpr("You hear a splashing noise.", MSGCH_SOUND);
        }

        return (true);
    }

    if (submerged())
        return (true);

    return (false);
}

bool monsters::cannot_fight() const
{
    return (mons_class_flag(type, M_NO_EXP_GAIN)
            || mons_is_statue(type));
}

void monsters::attacking(actor * /* other */)
{
}

// Sends a monster into a frenzy.
void monsters::go_frenzy()
{
    if (!can_go_berserk())
        return;

    if (has_ench(ENCH_SLOW))
    {
        del_ench(ENCH_SLOW, true); // Give no additional message.
        simple_monster_message(this,
            make_stringf(" shakes off %s lethargy.",
                         pronoun(PRONOUN_NOCAP_POSSESSIVE).c_str()).c_str());
    }
    del_ench(ENCH_HASTE, true);
    del_ench(ENCH_FATIGUE, true); // Give no additional message.

    const int duration = 16 + random2avg(13, 2);

    // store the attitude for later retrieval
    props["old_attitude"] = short(attitude);

    attitude = ATT_NEUTRAL;
    add_ench(mon_enchant(ENCH_INSANE, 0, KC_OTHER, duration * 10));
    add_ench(mon_enchant(ENCH_HASTE, 0, KC_OTHER, duration * 10));
    add_ench(mon_enchant(ENCH_MIGHT, 0, KC_OTHER, duration * 10));

    if (simple_monster_message(this, " flies into a frenzy!"))
        // Xom likes monsters going insane.
        xom_is_stimulated(friendly() ? 32 : 128);
}

void monsters::go_berserk(bool /* intentional */, bool /* potion */)
{
    if (!can_go_berserk())
        return;

    if (has_ench(ENCH_SLOW))
    {
        del_ench(ENCH_SLOW, true); // Give no additional message.
        simple_monster_message(this,
            make_stringf(" shakes off %s lethargy.",
                         pronoun(PRONOUN_NOCAP_POSSESSIVE).c_str()).c_str());
    }
    del_ench(ENCH_HASTE, true);
    del_ench(ENCH_FATIGUE, true); // Give no additional message.

    const int duration = 16 + random2avg(13, 2);
    add_ench(mon_enchant(ENCH_BERSERK, 0, KC_OTHER, duration * 10));
    add_ench(mon_enchant(ENCH_HASTE, 0, KC_OTHER, duration * 10));
    add_ench(mon_enchant(ENCH_MIGHT, 0, KC_OTHER, duration * 10));
    if (simple_monster_message(this, " goes berserk!"))
        // Xom likes monsters going berserk.
        xom_is_stimulated(friendly() ? 32 : 128);
}

void monsters::expose_to_element(beam_type flavour, int strength)
{
    switch (flavour)
    {
    case BEAM_COLD:
        if (mons_class_flag(type, M_COLD_BLOOD) && res_cold() <= 0
            && coinflip())
        {
            slow_down(this, strength);
        }
        break;
    default:
        break;
    }
}

void monsters::banish(const std::string &)
{
    coord_def old_pos = pos();

    if (!silenced(pos()) && can_speak())
        simple_monster_message(this, (" screams as " + pronoun(PRONOUN_NOCAP)
            + " is devoured by a tear in reality.").c_str(),
            MSGCH_BANISHMENT);
    else
        simple_monster_message(this, " is devoured by a tear in reality.",
            MSGCH_BANISHMENT);
    monster_die(this, KILL_RESET, NON_MONSTER);

    place_cloud(CLOUD_TLOC_ENERGY, old_pos, 5 + random2(8), KC_OTHER);
    for (adjacent_iterator ai(old_pos); ai; ++ai)
        if (!feat_is_solid(grd(*ai)) && env.cgrid(*ai) == EMPTY_CLOUD
            && coinflip())
        {
            place_cloud(CLOUD_TLOC_ENERGY, *ai, 1 + random2(8), KC_OTHER);
        }
}

bool monsters::has_spells() const
{
    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
        if (spells[i] != SPELL_NO_SPELL)
            return (true);

    return (false);
}

bool monsters::has_spell(spell_type spell) const
{
    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
        if (spells[i] == spell)
            return (true);

    return (false);
}

bool monsters::has_holy_spell() const
{
    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
        if (is_holy_spell(spells[i]))
            return (true);

    return (false);
}

bool monsters::has_unholy_spell() const
{
    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
        if (is_unholy_spell(spells[i]))
            return (true);

    return (false);
}

bool monsters::has_evil_spell() const
{
    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
        if (is_evil_spell(spells[i]))
            return (true);

    return (false);
}

bool monsters::has_unclean_spell() const
{
    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
        if (is_unclean_spell(spells[i]))
            return (true);

    return (false);
}

bool monsters::has_chaotic_spell() const
{
    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
        if (is_chaotic_spell(spells[i]))
            return (true);

    return (false);
}

bool monsters::has_attack_flavour(int flavour) const
{
    for (int i = 0; i < 4; ++i)
    {
        const int attk_flavour = mons_attack_spec(this, i).flavour;
        if (attk_flavour == flavour)
            return (true);
    }

    return (false);
}

bool monsters::has_damage_type(int dam_type)
{
    for (int i = 0; i < 4; ++i)
    {
        const int dmg_type = damage_type(i);
        if (dmg_type == dam_type)
            return (true);
    }

    return (false);
}

bool monsters::confused() const
{
    return (mons_is_confused(this));
}

bool monsters::confused_by_you() const
{
    if (mons_class_flag(type, M_CONFUSED))
        return false;

    const mon_enchant me = get_ench(ENCH_CONFUSION);
    return (me.ench == ENCH_CONFUSION && me.who == KC_YOU);
}

bool monsters::paralysed() const
{
    return this->has_ench(ENCH_PARALYSIS);
}

bool monsters::cannot_act() const
{
    return (paralysed()
            || petrified() && !petrifying());
}

bool monsters::cannot_move() const
{
    return (cannot_act() || petrifying());
}

bool monsters::asleep() const
{
    return (behaviour == BEH_SLEEP);
}

bool monsters::backlit(bool check_haloed) const
{
    return (has_ench(ENCH_CORONA) || has_ench(ENCH_STICKY_FLAME)
        || ((check_haloed) ? haloed() : false));
}

bool monsters::caught() const
{
    return this->has_ench(ENCH_HELD);
}

bool monsters::petrified() const
{
    return has_ench(ENCH_PETRIFIED);
}

bool monsters::petrifying() const
{
    return has_ench(ENCH_PETRIFYING);
}

bool monsters::friendly() const
{
    return (attitude == ATT_FRIENDLY || has_ench(ENCH_CHARM));
}

bool monsters::neutral() const
{
    return (attitude == ATT_NEUTRAL || has_ench(ENCH_TEMP_PACIF)
            || attitude == ATT_GOOD_NEUTRAL
            || attitude == ATT_STRICT_NEUTRAL);
}

bool monsters::good_neutral() const
{
    return (attitude == ATT_GOOD_NEUTRAL || has_ench(ENCH_TEMP_PACIF));
}

bool monsters::strict_neutral() const
{
    return (attitude == ATT_STRICT_NEUTRAL);
}

bool monsters::wont_attack() const
{
    return (friendly() || good_neutral() || strict_neutral());
}

bool monsters::pacified() const
{
    return (attitude == ATT_NEUTRAL && testbits(flags, MF_GOT_HALF_XP));
}

int monsters::shield_bonus() const
{
    const item_def *shld = const_cast<monsters*>(this)->shield();
    if (shld && get_armour_slot(*shld) == EQ_SHIELD)
    {
        // Note that 0 is not quite no-blocking.
        if (incapacitated())
            return (0);

        int shld_c = property(*shld, PARM_AC) + shld->plus;
        return (random2avg(shld_c + hit_dice * 2 / 3, 2));
    }
    return (-100);
}

int monsters::shield_block_penalty() const
{
    return (4 * shield_blocks * shield_blocks);
}

void monsters::shield_block_succeeded(actor *attacker)
{
    actor::shield_block_succeeded(attacker);

    ++shield_blocks;
}

int monsters::shield_bypass_ability(int) const
{
    return (15 + hit_dice * 2 / 3);
}

int monsters::armour_class() const
{
    return (ac);
}

int monsters::melee_evasion(const actor *act, ev_ignore_type evit) const
{
    int evasion = ev;

    if (evit & EV_IGNORE_HELPLESS)
        return (evasion);

    if (paralysed() || asleep())
        evasion = 0;
    else if (caught())
        evasion /= (body_size(PSIZE_BODY) + 2);
    else if (confused())
        evasion /= 2;
    return (evasion);
}

bool monsters::heal(int amount, bool max_too)
{
    if (mons_is_statue(type))
        return (false);

    if (amount < 1)
        return (false);
    else if (!max_too && hit_points == max_hit_points)
        return (false);

    hit_points += amount;

    bool success = true;

    if (hit_points > max_hit_points)
    {
        if (max_too)
        {
            const monsterentry* m = get_monster_data(type);
            const int maxhp =
                m->hpdice[0] * (m->hpdice[1] + m->hpdice[2]) + m->hpdice[3];

            // Limit HP growth.
            if (random2(3 * maxhp) > 2 * max_hit_points)
                max_hit_points++;
            else
                success = false;
        }

        hit_points = max_hit_points;
    }

    return (success);
}

mon_holy_type monsters::holiness() const
{
    if (testbits(flags, MF_HONORARY_UNDEAD))
        return (MH_UNDEAD);

    return (mons_class_holiness(type));
}

bool monsters::undead_or_demonic() const
{
    const mon_holy_type holi = holiness();

    return (holi == MH_UNDEAD || holi == MH_DEMONIC);
}

bool monsters::is_holy() const
{
    if (holiness() == MH_HOLY)
        return (true);

    // Assume that all unknown gods (GOD_NAMELESS) are not holy.
    if (is_priest() && is_good_god(god))
        return (true);

    if (has_holy_spell())
        return (true);

    return (false);
}

bool monsters::is_unholy() const
{
    if (type == MONS_SILVER_STATUE)
        return (true);

    if (holiness() == MH_DEMONIC)
        return (true);

    if (has_unholy_spell())
        return (true);

    return (false);
}

bool monsters::is_evil() const
{
    if (holiness() == MH_UNDEAD)
        return (true);

    // Assume that all unknown gods (GOD_NAMELESS) are evil.
    if (is_priest() && (is_evil_god(god) || god == GOD_NAMELESS))
        return (true);

    if (has_evil_spell())
        return (true);

    if (has_attack_flavour(AF_DRAIN_XP)
        || has_attack_flavour(AF_VAMPIRIC))
    {
        return (true);
    }

    return (false);
}

bool monsters::is_unclean() const
{
    if (has_unclean_spell())
        return (true);

    if (has_attack_flavour(AF_DISEASE)
        || has_attack_flavour(AF_HUNGER)
        || has_attack_flavour(AF_ROT)
        || has_attack_flavour(AF_STEAL)
        || has_attack_flavour(AF_STEAL_FOOD))
    {
        return (true);
    }

    return (false);
}

bool monsters::is_chaotic() const
{
    if (type == MONS_UGLY_THING || type == MONS_VERY_UGLY_THING
        || type == MONS_CRAZY_YIUF)
    {
        return (true);
    }

    if (is_shapeshifter())
        return (true);

    // Assume that all unknown gods (GOD_NAMELESS) are not chaotic.
    if (is_priest() && is_chaotic_god(god))
        return (true);

    if (has_chaotic_spell())
        return (true);

    if (has_attack_flavour(AF_MUTATE)
        || has_attack_flavour(AF_KLOWN)
        || has_attack_flavour(AF_CHAOS))
    {
        return (true);
    }

    return (false);
}

int monsters::res_fire() const
{
    const mon_resist_def res = get_mons_resists(this);

    int u = std::min(res.fire + res.hellfire * 3, 3);

    if (mons_itemuse(this) >= MONUSE_STARTING_EQUIPMENT)
    {
        u += scan_mon_inv_randarts(this, ARTP_FIRE);

        const int armour = inv[MSLOT_ARMOUR];
        const int shld = inv[MSLOT_SHIELD];

        if (armour != NON_ITEM && mitm[armour].base_type == OBJ_ARMOUR)
        {
            // intrinsic armour abilities
            switch (mitm[armour].sub_type)
            {
            case ARM_DRAGON_ARMOUR:      u += 2; break;
            case ARM_GOLD_DRAGON_ARMOUR: u += 1; break;
            case ARM_ICE_DRAGON_ARMOUR:  u -= 1; break;
            default:                             break;
            }

            // check ego resistance
            const int ego = get_armour_ego_type(mitm[armour]);
            if (ego == SPARM_FIRE_RESISTANCE || ego == SPARM_RESISTANCE)
                u += 1;
        }

        if (shld != NON_ITEM && mitm[shld].base_type == OBJ_ARMOUR)
        {
            // check ego resistance
            const int ego = get_armour_ego_type(mitm[shld]);
            if (ego == SPARM_FIRE_RESISTANCE || ego == SPARM_RESISTANCE)
                u += 1;
        }
    }

    if (u < -3)
        u = -3;
    else if (u > 3)
        u = 3;

    return (u);
}

int monsters::res_steam() const
{
    int res = get_mons_resists(this).steam;
    if (has_equipped(EQ_BODY_ARMOUR, ARM_STEAM_DRAGON_ARMOUR))
        res += 3;
    return (res + res_fire() / 2);
}

int monsters::res_cold() const
{
    int u = get_mons_resists(this).cold;

    if (mons_itemuse(this) >= MONUSE_STARTING_EQUIPMENT)
    {
        u += scan_mon_inv_randarts(this, ARTP_COLD);

        const int armour = inv[MSLOT_ARMOUR];
        const int shld = inv[MSLOT_SHIELD];

        if (armour != NON_ITEM && mitm[armour].base_type == OBJ_ARMOUR)
        {
            // intrinsic armour abilities
            switch (mitm[armour].sub_type)
            {
            case ARM_ICE_DRAGON_ARMOUR:  u += 2; break;
            case ARM_GOLD_DRAGON_ARMOUR: u += 1; break;
            case ARM_DRAGON_ARMOUR:      u -= 1; break;
            default:                             break;
            }

            // check ego resistance
            const int ego = get_armour_ego_type(mitm[armour]);
            if (ego == SPARM_COLD_RESISTANCE || ego == SPARM_RESISTANCE)
                u += 1;
        }

        if (shld != NON_ITEM && mitm[shld].base_type == OBJ_ARMOUR)
        {
            // check ego resistance
            const int ego = get_armour_ego_type(mitm[shld]);
            if (ego == SPARM_COLD_RESISTANCE || ego == SPARM_RESISTANCE)
                u += 1;
        }
    }

    if (u < -3)
        u = -3;
    else if (u > 3)
        u = 3;

    return (u);
}

int monsters::res_elec() const
{
    // This is a variable, not a player_xx() function, so can be above 1.
    int u = 0;

    u += get_mons_resists(this).elec;

    // Don't bother checking equipment if the monster can't use it.
    if (mons_itemuse(this) >= MONUSE_STARTING_EQUIPMENT)
    {
        u += scan_mon_inv_randarts(this, ARTP_ELECTRICITY);

        // No ego armour, but storm dragon.
        const int armour = inv[MSLOT_ARMOUR];
        if (armour != NON_ITEM && mitm[armour].base_type == OBJ_ARMOUR
            && mitm[armour].sub_type == ARM_STORM_DRAGON_ARMOUR)
        {
            u += 1;
        }
    }

    // Monsters can legitimately get multiple levels of electricity resistance.

    return (u);
}

int monsters::res_asphyx() const
{
    int res = get_mons_resists(this).asphyx;
    const mon_holy_type holi = holiness();
    if (undead_or_demonic()
        || holi == MH_NONLIVING
        || holi == MH_PLANT)
    {
        res += 1;
    }
    return (res);
}

int monsters::res_water_drowning() const
{
    const int res = res_asphyx();
    if (res)
        return res;
    switch (mons_habitat(this))
    {
    case HT_WATER:
    case HT_AMPHIBIOUS_WATER:
        return 1;
    default:
        return 0;
    }
}

int monsters::res_poison() const
{
    int u = get_mons_resists(this).poison;

    if (mons_itemuse(this) >= MONUSE_STARTING_EQUIPMENT)
    {
        u += scan_mon_inv_randarts(this, ARTP_POISON);

        const int armour = this->inv[MSLOT_ARMOUR];
        const int shld = this->inv[MSLOT_SHIELD];

        if (armour != NON_ITEM && mitm[armour].base_type == OBJ_ARMOUR)
        {
            // intrinsic armour abilities
            switch (mitm[armour].sub_type)
            {
            case ARM_SWAMP_DRAGON_ARMOUR: u += 1; break;
            case ARM_GOLD_DRAGON_ARMOUR:  u += 1; break;
            default:                              break;
            }

            // ego armour resistance
            if (get_armour_ego_type(mitm[armour]) == SPARM_POISON_RESISTANCE)
                u += 1;
        }

        if (shld != NON_ITEM && mitm[shld].base_type == OBJ_ARMOUR)
        {
            // ego armour resistance
            if (get_armour_ego_type(mitm[shld]) == SPARM_POISON_RESISTANCE)
                u += 1;
        }
    }

    // Monsters can legitimately get multiple levels of poison resistance.

    return (u);
}

int monsters::res_sticky_flame() const
{
    int res = get_mons_resists(this).sticky_flame;
    if (mons_is_insubstantial(type))
        res += 1;
    if (has_equipped(EQ_BODY_ARMOUR, ARM_MOTTLED_DRAGON_ARMOUR))
        res += 1;
    return (res);
}

int monsters::res_rotting() const
{
    int res = get_mons_resists(this).rotting;
    if (holiness() != MH_NATURAL)
        res += 1;
    return (res);
}

int monsters::res_holy_energy(const actor *attacker) const
{
    if (undead_or_demonic())
        return (-2);

    if (is_evil())
        return (-1);

    if (is_holy()
        || is_good_god(god)
        || neutral()
        || is_unchivalric_attack(attacker, this)
        || is_good_god(you.religion) && is_follower(this))
    {
        return (1);
    }

    return (0);
}

int monsters::res_negative_energy() const
{
    if (holiness() != MH_NATURAL
        || type == MONS_SHADOW_DRAGON)
    {
        return (3);
    }

    int u = 0;

    if (mons_itemuse(this) >= MONUSE_STARTING_EQUIPMENT)
    {
        u += scan_mon_inv_randarts(this, ARTP_NEGATIVE_ENERGY);

        const int armour = this->inv[MSLOT_ARMOUR];
        const int shld = this->inv[MSLOT_SHIELD];

        if (armour != NON_ITEM && mitm[armour].base_type == OBJ_ARMOUR)
        {
            // check for ego resistance
            if (get_armour_ego_type(mitm[armour]) == SPARM_POSITIVE_ENERGY)
                u += 1;
        }

        if (shld != NON_ITEM && mitm[shld].base_type == OBJ_ARMOUR)
        {
            // check for ego resistance
            if (get_armour_ego_type(mitm[shld]) == SPARM_POSITIVE_ENERGY)
                u += 1;
        }
    }

    if (u > 3)
        u = 3;

    return (u);
}

int monsters::res_torment() const
{
    const mon_holy_type holy = holiness();
    if (holy == MH_UNDEAD
        || holy == MH_DEMONIC
        || holy == MH_NONLIVING)
    {
        return (1);
    }

    return (0);
}

int monsters::res_acid() const
{
    return (get_mons_resists(this).acid);
}

int monsters::res_magic() const
{
    if (mons_immune_magic(this))
        return MAG_IMMUNE;

    int u = (get_monster_data(this->type))->resist_magic;

    // Negative values get multiplied with monster hit dice.
    if (u < 0)
        u = this->hit_dice * -u * 4 / 3;

    // Randarts have a multiplicative effect.
    u *= (scan_mon_inv_randarts(this, ARTP_MAGIC) + 100);
    u /= 100;

    // ego armour resistance
    const int armour = this->inv[MSLOT_ARMOUR];
    const int _shield = this->inv[MSLOT_SHIELD];

    if (armour != NON_ITEM
        && get_armour_ego_type( mitm[armour] ) == SPARM_MAGIC_RESISTANCE )
    {
        u += 30;
    }

    if (_shield != NON_ITEM
        && get_armour_ego_type( mitm[_shield] ) == SPARM_MAGIC_RESISTANCE )
    {
        u += 30;
    }

    if (this->has_ench(ENCH_LOWERED_MR))
        u /= 2;

    return (u);
}

flight_type monsters::flight_mode() const
{
    return (mons_flies(this));
}

bool monsters::is_levitating() const
{
    // Checking class flags is not enough - see mons_flies.
    return (flight_mode() == FL_LEVITATE);
}

int monsters::mons_species() const
{
    return ::mons_species(type);
}

void monsters::poison(actor *agent, int amount)
{
    if (amount <= 0)
        return;

    // Scale poison down for monsters.
    if (!(amount /= 2))
        amount = 1;

    poison_monster(this, agent ? agent->kill_alignment() : KC_OTHER, amount);
}

int monsters::skill(skill_type sk, bool) const
{
    switch (sk)
    {
    case SK_NECROMANCY:
        return (holiness() == MH_UNDEAD ? hit_dice / 2 : hit_dice / 3);

    default:
        return (0);
    }
}

void monsters::blink(bool)
{
    monster_blink(this);
}

void monsters::teleport(bool now, bool, bool)
{
    monster_teleport(this, now, false);
}

bool monsters::alive() const
{
    return (hit_points > 0 && type != MONS_NO_MONSTER);
}

god_type monsters::deity() const
{
    return (god);
}

bool monsters::drain_exp(actor *agent, bool quiet, int pow)
{
    if (x_chance_in_y(res_negative_energy(), 3))
        return (false);

    if (!quiet && you.can_see(this))
        mprf("%s is drained!", name(DESC_CAP_THE).c_str());

    // If quiet, don't clean up the monster in order to credit properly.
    hurt(agent, 2 + random2(pow), BEAM_NEG, !quiet);

    if (alive())
    {
        if (x_chance_in_y(pow, 15))
        {
            hit_dice--;
            experience = 0;
        }

        max_hit_points -= 2 + random2(pow);
        hit_points = std::min(max_hit_points, hit_points);
    }

    return (true);
}

bool monsters::rot(actor *agent, int amount, int immediate, bool quiet)
{
    if (res_rotting() || amount <= 0)
        return (false);

    if (!quiet && you.can_see(this))
    {
        mprf("%s %s!", name(DESC_CAP_THE).c_str(),
             amount > 0 ? "rots" : "looks less resilient");
    }

    // Apply immediate damage because we can't handle rotting for
    // monsters yet.
    if (immediate > 0)
    {
        // If quiet, don't clean up the monster in order to credit
        // properly.
        hurt(agent, immediate, BEAM_MISSILE, !quiet);

        if (alive())
        {
            max_hit_points -= immediate * 2;
            hit_points = std::min(max_hit_points, hit_points);
        }
    }

    add_ench(mon_enchant(ENCH_ROT, std::min(amount, 4),
                         agent->kill_alignment()));

    return (true);
}

int monsters::hurt(const actor *agent, int amount, beam_type flavour,
                   bool cleanup_dead)
{
    if (alive())
    {
        if (amount == INSTANT_DEATH)
            amount = hit_points;
        else if (hit_dice <= 0)
            amount = hit_points;
        else if (amount <= 0 && hit_points <= max_hit_points)
            return (0);

        amount = std::min(amount, hit_points);
        hit_points -= amount;

        if (hit_points > max_hit_points)
        {
            amount    += hit_points - max_hit_points;
            hit_points = max_hit_points;
        }

        if (flavour == BEAM_NUKE || flavour == BEAM_DISINTEGRATION)
        {
            if (can_bleed())
                blood_spray(pos(), id(), amount / 5);

            if (!alive())
                flags |= MF_EXPLODE_KILL;
        }

        // Allow the victim to exhibit passive damage behaviour (royal
        // jelly).
        kill_category whose = (agent == NULL) ? KC_OTHER :
                              (agent->atype() == ACT_PLAYER) ? KC_YOU :
                               ((monsters*)agent)->friendly() ? KC_FRIENDLY :
                                                KC_OTHER;
        react_to_damage(amount, flavour, whose);
    }

    if (cleanup_dead && (hit_points <= 0 || hit_dice <= 0) && type != -1)
    {
        if (agent == NULL)
            monster_die(this, KILL_MISC, NON_MONSTER);
        else if (agent->atype() == ACT_PLAYER)
            monster_die(this, KILL_YOU, NON_MONSTER);
        else
            monster_die(this, KILL_MON, agent->mindex());
    }

    return (amount);
}

void monsters::confuse(actor *atk, int strength)
{
    enchant_monster_with_flavour(this, atk, BEAM_CONFUSION, strength);
}

void monsters::paralyse(actor *atk, int strength)
{
    enchant_monster_with_flavour(this, atk, BEAM_PARALYSIS, strength);
}

void monsters::petrify(actor *atk, int strength)
{
    if (mons_is_insubstantial(type))
        return;

    enchant_monster_with_flavour(this, atk, BEAM_PETRIFY, strength);
}

void monsters::slow_down(actor *atk, int strength)
{
    enchant_monster_with_flavour(this, atk, BEAM_SLOW, strength);
}

void monsters::set_ghost(const ghost_demon &g, bool has_name)
{
    ghost.reset(new ghost_demon(g));

    if (has_name)
        mname = ghost->name;
}

void monsters::pandemon_init()
{
    hit_dice        = ghost->xl;
    max_hit_points  = ghost->max_hp;
    hit_points      = max_hit_points;
    ac              = ghost->ac;
    ev              = ghost->ev;
    flags           = MF_INTERESTING;
    // Don't make greased-lightning Pandemonium demons in the dungeon
    // max speed = 17).  Demons in Pandemonium can be up to speed 24.
    if (you.level_type == LEVEL_DUNGEON)
        speed = (one_chance_in(3) ? 10 : 7 + roll_dice(2, 5));
    else
        speed = (one_chance_in(3) ? 10 : 10 + roll_dice(2, 7));

    speed_increment = 70;

    if (you.char_direction == GDT_ASCENDING && you.level_type == LEVEL_DUNGEON)
        colour = LIGHTRED;
    else
        colour = ghost->colour;

    load_spells(MST_GHOST);
}

void monsters::ghost_init()
{
    type            = MONS_PLAYER_GHOST;
    god             = ghost->religion;
    hit_dice        = ghost->xl;
    max_hit_points  = ghost->max_hp;
    hit_points      = max_hit_points;
    ac              = ghost->ac;
    ev              = ghost->ev;
    speed           = ghost->speed;
    speed_increment = 70;
    attitude        = ATT_HOSTILE;
    behaviour       = BEH_WANDER;
    flags           = MF_INTERESTING;
    foe             = MHITNOT;
    foe_memory      = 0;
    colour          = ghost->colour;
    number          = MONS_NO_MONSTER;
    load_spells(MST_GHOST);

    inv.init(NON_ITEM);
    enchantments.clear();
    ench_countdown = 0;

    // Summoned player ghosts are already given a position; calling this
    // in those instances will cause a segfault. Instead, check to see
    // if we have a home first. {due}
    if (!in_bounds(pos()))
        find_place_to_live();
}

void monsters::uglything_init(bool only_mutate)
{
    // If we're mutating an ugly thing, leave its experience level, hit
    // dice and maximum and current hit points as they are.
    if (!only_mutate)
    {
        hit_dice        = ghost->xl;
        max_hit_points  = ghost->max_hp;
        hit_points      = max_hit_points;
    }

    ac              = ghost->ac;
    ev              = ghost->ev;
    speed           = ghost->speed;
    speed_increment = 70;
    colour          = ghost->colour;
}

void monsters::dancing_weapon_init()
{
    hit_dice        = ghost->xl;
    max_hit_points  = ghost->max_hp;

    hit_points      = max_hit_points;
    ac              = ghost->ac;
    ev              = ghost->ev;
    speed           = ghost->speed;
    speed_increment = 70;
    colour          = ghost->colour;
}

void monsters::uglything_mutate(unsigned char force_colour)
{
    ghost->init_ugly_thing(type == MONS_VERY_UGLY_THING, true, force_colour);
    uglything_init(true);
}

void monsters::uglything_upgrade()
{
    ghost->ugly_thing_to_very_ugly_thing();
    uglything_init();
}

bool monsters::check_set_valid_home(const coord_def &place,
                                    coord_def &chosen,
                                    int &nvalid) const
{
    if (!in_bounds(place))
        return (false);

    if (actor_at(place))
        return (false);

    if (!monster_habitable_grid(this, grd(place)))
        return (false);

    if (one_chance_in(++nvalid))
        chosen = place;

    return (true);
}

bool monsters::find_home_around(const coord_def &c, int radius)
{
    coord_def place(-1, -1);
    int nvalid = 0;
    for (int yi = -radius; yi <= radius; ++yi)
    {
        const coord_def c1(c.x - radius, c.y + yi);
        const coord_def c2(c.x + radius, c.y + yi);
        check_set_valid_home(c1, place, nvalid);
        check_set_valid_home(c2, place, nvalid);
    }

    for (int xi = -radius + 1; xi < radius; ++xi)
    {
        const coord_def c1(c.x + xi, c.y - radius);
        const coord_def c2(c.x + xi, c.y + radius);
        check_set_valid_home(c1, place, nvalid);
        check_set_valid_home(c2, place, nvalid);
    }

    if (nvalid)
    {
        moveto(place);
        return (true);
    }

    return (false);
}

bool monsters::find_home_near_place(const coord_def &c)
{
    for (int radius = 1; radius < 7; ++radius)
        if (find_home_around(c, radius))
            return (true);

    return (false);
}

bool monsters::find_home_near_player()
{
    return (find_home_near_place(you.pos()));
}

bool monsters::find_home_anywhere()
{
    coord_def place(-1, -1);
    int nvalid = 0;
    for (int tries = 0; tries < 600; ++tries)
    {
        if (check_set_valid_home(random_in_bounds(), place, nvalid))
        {
            moveto(place);
            return (true);
        }
    }

    return (false);
}

bool monsters::find_place_to_live(bool near_player)
{
    if (near_player && find_home_near_player()
        || find_home_anywhere())
    {
        mgrd(pos()) = mindex();
        return (true);
    }

    return (false);
}

void monsters::destroy_inventory()
{
    for (int j = 0; j < NUM_MONSTER_SLOTS; j++)
    {
        if (inv[j] != NON_ITEM)
        {
            destroy_item( inv[j] );
            inv[j] = NON_ITEM;
        }
    }
}

bool monsters::is_travelling() const
{
    return (!travel_path.empty());
}

bool monsters::is_patrolling() const
{
    return (!patrol_point.origin());
}

bool monsters::needs_transit() const
{
    return ((mons_is_unique(type)
                || (flags & MF_BANISHED)
                || you.level_type == LEVEL_DUNGEON
                   && hit_dice > 8 + random2(25)
                   && mons_can_use_stairs(this))
            && !is_summoned());
}

void monsters::set_transit(const level_id &dest)
{
    add_monster_to_transit(dest, *this);
}

void monsters::load_spells(mon_spellbook_type book)
{
    spells.init(SPELL_NO_SPELL);
    if (book == MST_NO_SPELLS || book == MST_GHOST && !ghost.get())
        return;

#if DEBUG_DIAGNOSTICS
    mprf( MSGCH_DIAGNOSTICS, "%s: loading spellbook #%d",
          name(DESC_PLAIN).c_str(), static_cast<int>(book) );
#endif

    if (book == MST_GHOST)
        spells = ghost->spells;
    else
    {
        for (unsigned int i = 0; i < ARRAYSZ(mspell_list); ++i)
        {
            if (mspell_list[i].type == book)
            {
                for (int j = 0; j < NUM_MONSTER_SPELL_SLOTS; ++j)
                    spells[j] = mspell_list[i].spells[j];
                break;
            }
        }
    }
#if DEBUG_DIAGNOSTICS
    // Only for ghosts, too spammy to use for all monsters.
    if (book == MST_GHOST)
    {
        for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; i++)
        {
            mprf( MSGCH_DIAGNOSTICS, "Spell #%d: %d (%s)",
                  i, spells[i], spell_title(spells[i]) );
        }
    }
#endif
}

bool monsters::has_hydra_multi_attack() const
{
    return (mons_species() == MONS_HYDRA
            || mons_is_zombified(this) && base_monster == MONS_HYDRA);
}

bool monsters::has_multitargeting() const
{
    if (mons_class_wields_two_weapons(type))
        return (true);

    // Hacky little list for now. evk
    return (type == MONS_HYDRA
            || type == MONS_TENTACLED_MONSTROSITY
            || type == MONS_ELECTRIC_GOLEM);
}

bool monsters::can_use_spells() const
{
    return (flags & MF_SPELLCASTER);
}

bool monsters::is_priest() const
{
    return (flags & MF_PRIEST);
}

bool monsters::is_actual_spellcaster() const
{
    return (flags & MF_ACTUAL_SPELLS);
}

bool monsters::is_shapeshifter() const
{
    return (has_ench(ENCH_GLOWING_SHAPESHIFTER, ENCH_SHAPESHIFTER));
}

bool monsters::has_ench(enchant_type ench) const
{
    return (enchantments.find(ench) != enchantments.end());
}

bool monsters::has_ench(enchant_type ench, enchant_type ench2) const
{
    if (ench2 == ENCH_NONE)
        ench2 = ench;

    for (int i = ench; i <= ench2; ++i)
        if (has_ench(static_cast<enchant_type>(i)))
            return (true);

    return (false);
}

mon_enchant monsters::get_ench(enchant_type ench1,
                               enchant_type ench2) const
{
    if (ench2 == ENCH_NONE)
        ench2 = ench1;

    for (int e = ench1; e <= ench2; ++e)
    {
        mon_enchant_list::const_iterator i =
            enchantments.find(static_cast<enchant_type>(e));

        if (i != enchantments.end())
            return (i->second);
    }

    return mon_enchant();
}

void monsters::update_ench(const mon_enchant &ench)
{
    if (ench.ench != ENCH_NONE)
    {
        mon_enchant_list::iterator i = enchantments.find(ench.ench);
        if (i != enchantments.end())
            i->second = ench;
    }
}

bool monsters::add_ench(const mon_enchant &ench)
{
    // silliness
    if (ench.ench == ENCH_NONE)
        return (false);

    if (ench.ench == ENCH_FEAR
        && (holiness() == MH_NONLIVING || berserk()))
    {
        return (false);
    }

    mon_enchant_list::iterator i = enchantments.find(ench.ench);
    bool new_enchantment = false;
    mon_enchant *added = NULL;
    if (i == enchantments.end())
    {
        new_enchantment = true;
        added = &(enchantments[ench.ench] = ench);
    }
    else
    {
        i->second += ench;
        added = &i->second;
    }

    // If the duration is not set, we must calculate it (depending on the
    // enchantment).
    if (!ench.duration)
        added->set_duration(this, new_enchantment ? NULL : &ench);

    if (new_enchantment)
        add_enchantment_effect(ench);

    return (true);
}

void monsters::forget_random_spell()
{
    int which_spell = -1;
    int count = 0;
    for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
        if (spells[i] != SPELL_NO_SPELL && one_chance_in(++count))
            which_spell = i;
    if (which_spell != -1)
        spells[which_spell] = SPELL_NO_SPELL;
}

void monsters::add_enchantment_effect(const mon_enchant &ench, bool quiet)
{
    // Check for slow/haste.
    switch (ench.ench)
    {
    case ENCH_INSANE:
    case ENCH_BERSERK:
        // Inflate hp.
        scale_hp(3, 2);

        if (has_ench(ENCH_SUBMERGED))
            del_ench(ENCH_SUBMERGED);

        if (mons_is_lurking(this))
        {
            behaviour = BEH_WANDER;
            behaviour_event(this, ME_EVAL);
        }
        break;

    case ENCH_HASTE:
        if (speed >= 100)
            speed = 100 + ((speed - 100) * 2);
        else
            speed *= 2;

        break;

    case ENCH_SLOW:
        if (speed >= 100)
            speed = 100 + ((speed - 100) / 2);
        else
            speed /= 2;

        break;

    case ENCH_SUBMERGED:
        mons_clear_trapping_net(this);

        // Don't worry about invisibility.  You should be able to see if
        // something has submerged.
        if (!quiet && mons_near(this))
        {
            if (type == MONS_AIR_ELEMENTAL)
            {
                mprf("%s merges itself into the air.",
                     name(DESC_CAP_A, true).c_str());
            }
            else if (type == MONS_TRAPDOOR_SPIDER)
            {
                mprf("%s hides itself under the floor.",
                     name(DESC_CAP_A, true).c_str());
            }
            else if (seen_context == "surfaces"
                     || seen_context == "bursts forth"
                     || seen_context == "emerges")
            {
                // The monster surfaced and submerged in the same turn
                // without doing anything else.
                interrupt_activity(AI_SEE_MONSTER,
                                   activity_interrupt_data(this,
                                                           "surfaced"));
            }
            else if (crawl_state.arena)
                mprf("%s submerges.", name(DESC_CAP_A, true).c_str());
        }

        // Pacified monsters leave the level when they submerge.
        if (pacified())
            make_mons_leave_level(this);
        break;

    case ENCH_CONFUSION:
        if (type == MONS_TRAPDOOR_SPIDER && has_ench(ENCH_SUBMERGED))
            del_ench(ENCH_SUBMERGED);

        if (mons_is_lurking(this))
        {
            behaviour = BEH_WANDER;
            behaviour_event(this, ME_EVAL);
        }
        break;

    case ENCH_CHARM:
        behaviour = BEH_SEEK;
        target    = you.pos();
        foe       = MHITYOU;

        if (is_patrolling())
        {
            // Enslaved monsters stop patrolling and forget their patrol
            // point; they're supposed to follow you now.
            patrol_point.reset();
        }
        if (you.can_see(this))
            learned_something_new(TUT_MONSTER_FRIENDLY, pos());
        break;

    default:
        break;
    }
}

static bool _prepare_del_ench(monsters* mon, const mon_enchant &me)
{
    if (me.ench != ENCH_SUBMERGED)
        return (true);

    // Lurking monsters only unsubmerge when their foe is in sight if the foe
    // is right next to them.
    if (mons_is_lurking(mon))
    {
        const actor* foe = mon->get_foe();
        if (foe != NULL && mon->can_see(foe)
            && !adjacent(mon->pos(), foe->pos()))
        {
            return (false);
        }
    }

    int midx = mon->mindex();

    if (!monster_at(mon->pos()))
        mgrd(mon->pos()) = midx;

    if (mon->pos() != you.pos() && midx == mgrd(mon->pos()))
        return (true);

    if (midx != mgrd(mon->pos()))
    {
        monsters* other_mon = &menv[mgrd(mon->pos())];

        if (other_mon->type == MONS_NO_MONSTER
            || other_mon->type == MONS_PROGRAM_BUG)
        {
            mgrd(mon->pos()) = midx;

            mprf(MSGCH_ERROR, "mgrd(%d,%d) points to %s monster, even "
                 "though it contains submerged monster %s (see bug 2293518)",
                 mon->pos().x, mon->pos().y,
                 other_mon->type == MONS_NO_MONSTER ? "dead" : "buggy",
                 mon->name(DESC_PLAIN, true).c_str());

            if (mon->pos() != you.pos())
                return (true);
        }
        else
            mprf(MSGCH_ERROR, "%s tried to unsubmerge while on same square as "
                 "%s (see bug 2293518)", mon->name(DESC_CAP_THE, true).c_str(),
                 mon->name(DESC_NOCAP_A, true).c_str());
    }

    // Monster un-submerging while under player or another monster.  Try to
    // move to an adjacent square in which the monster could have been
    // submerged and have it unsubmerge from there.
    coord_def target_square;
    int       okay_squares = 0;

    for (adjacent_iterator ai(you.pos()); ai; ++ai)
        if (!actor_at(*ai)
            && monster_can_submerge(mon, grd(*ai))
            && one_chance_in(++okay_squares))
        {
            target_square = *ai;
        }

    if (okay_squares > 0)
    {
        mon->move_to_pos(target_square);
        return (true);
    }

    // No available adjacent squares from which the monster could also
    // have unsubmerged.  Can it just stay submerged where it is?
    if (monster_can_submerge(mon, grd(mon->pos())))
        return (false);

    // The terrain changed and the monster can't remain submerged.
    // Try to move to an adjacent square where it would be happy.
    for (adjacent_iterator ai(you.pos()); ai; ++ai)
    {
        if (!monster_at(*ai)
            && monster_habitable_grid(mon, grd(*ai))
            && !find_trap(*ai))
        {
            if (one_chance_in(++okay_squares))
                target_square = *ai;
        }
    }

    if (okay_squares > 0)
        mon->move_to_pos(target_square);

    return (true);
}

bool monsters::del_ench(enchant_type ench, bool quiet, bool effect)
{
    mon_enchant_list::iterator i = enchantments.find(ench);
    if (i == enchantments.end())
        return (false);

    const mon_enchant me = i->second;
    const enchant_type et = i->first;

    if (!_prepare_del_ench(this, me))
        return (false);

    enchantments.erase(et);
    if (effect)
        remove_enchantment_effect(me, quiet);
    return (true);
}

void monsters::remove_enchantment_effect(const mon_enchant &me, bool quiet)
{
    switch (me.ench)
    {
    case ENCH_TIDE:
        shoals_release_tide(this);
        break;

    case ENCH_INSANE:
        attitude = static_cast<mon_attitude_type>(props["old_attitude"].get_short());
        // deliberate fall through

    case ENCH_BERSERK:
        scale_hp(2, 3);
        break;

    case ENCH_HASTE:
        if (speed >= 100)
            speed = 100 + ((speed - 100) / 2);
        else
            speed /= 2;
        if (!quiet)
            simple_monster_message(this, " is no longer moving quickly.");
        break;

    case ENCH_SWIFT:
        if (!quiet)
            simple_monster_message(this, " is no longer moving somewhat quickly.");
        break;

    case ENCH_MIGHT:
        if (!quiet)
            simple_monster_message(this, " no longer looks unusually strong.");
        break;

    case ENCH_SLOW:
        if (!quiet)
            simple_monster_message(this, " is no longer moving slowly.");
        if (speed >= 100)
            speed = 100 + ((speed - 100) * 2);
        else
            speed *= 2;

        break;

    case ENCH_PARALYSIS:
        if (!quiet)
            simple_monster_message(this, " is no longer paralysed.");

        behaviour_event(this, ME_EVAL);
        break;

    case ENCH_TEMP_PACIF:
        if (!quiet)
            simple_monster_message(this, (" seems to come to "
                + pronoun(PRONOUN_NOCAP_POSSESSIVE) + " senses.").c_str());
        // Yeah, this _is_ offensive to Zin, but hey, he deserves it (1KB).

        behaviour_event(this, ME_EVAL);
        break;

    case ENCH_PETRIFIED:
        if (!quiet)
            simple_monster_message(this, " is no longer petrified.");
        del_ench(ENCH_PETRIFYING);

        behaviour_event(this, ME_EVAL);
        break;

    case ENCH_PETRIFYING:
        if (!petrified())
            break;

        if (!quiet)
            simple_monster_message(this, " stops moving altogether!");

        behaviour_event(this, ME_EVAL);
        break;

    case ENCH_FEAR:
        if (holiness() == MH_NONLIVING || berserk())
        {
            // This should only happen because of fleeing sanctuary
            snprintf(info, INFO_SIZE, " stops retreating.");
        }
        else
        {
            snprintf(info, INFO_SIZE, " seems to regain %s courage.",
                     this->pronoun(PRONOUN_NOCAP_POSSESSIVE, true).c_str());
        }

        if (!quiet)
            simple_monster_message(this, info);

        // Reevaluate behaviour.
        behaviour_event(this, ME_EVAL);
        break;

    case ENCH_CONFUSION:
        if (!quiet)
            simple_monster_message(this, " seems less confused.");

        // Reevaluate behaviour.
        behaviour_event(this, ME_EVAL);
        break;

    case ENCH_INVIS:
        // Invisible monsters stay invisible.
        if (mons_class_flag(type, M_INVIS))
            add_ench(mon_enchant(ENCH_INVIS));
        else if (mons_near(this) && !you.can_see_invisible()
                 && !has_ench(ENCH_SUBMERGED))
        {
            if (!quiet)
            {
                mprf("%s appears from thin air!",
                     name(DESC_CAP_A, true).c_str());
                autotoggle_autopickup(false);
            }

            handle_seen_interrupt(this);
        }
        break;

    case ENCH_CHARM:
        if (!quiet)
            simple_monster_message(this, " is no longer charmed.");

        if (you.can_see(this))
        {
            // and fire activity interrupts
            interrupt_activity(AI_SEE_MONSTER,
                               activity_interrupt_data(this, "uncharm"));
        }

        if (is_patrolling())
        {
            // Enslaved monsters stop patrolling and forget their patrol point,
            // in case they were on order to wait.
            patrol_point.reset();
        }

        // Reevaluate behaviour.
        behaviour_event(this, ME_EVAL);
        break;

    case ENCH_CORONA:
        if (!quiet)
        {
            if (visible_to(&you))
                simple_monster_message(this, " stops glowing.");
            else if (has_ench(ENCH_INVIS) && mons_near(this))
            {
                mprf("%s stops glowing and disappears.",
                     name(DESC_CAP_THE, true).c_str());
            }
        }
        break;

    case ENCH_STICKY_FLAME:
        if (!quiet)
            simple_monster_message(this, " stops burning.");
        break;

    case ENCH_POISON:
        if (!quiet)
            simple_monster_message(this, " looks more healthy.");
        break;

    case ENCH_ROT:
        if (!quiet)
            simple_monster_message(this, " is no longer rotting.");
        break;

    case ENCH_HELD:
    {
        int net = get_trapping_net(this->pos());
        if (net != NON_ITEM)
            remove_item_stationary(mitm[net]);

        if (!quiet)
            simple_monster_message(this, " breaks free.");
        break;
    }
    case ENCH_ABJ:
    case ENCH_SHORT_LIVED:
        // Set duration to -1 so that monster_die() and any of its
        // callees can tell that the monster ran out of time or was
        // abjured.
        add_ench(mon_enchant(ENCH_ABJ, 0, KC_OTHER, -1));

        if (berserk())
            simple_monster_message(this, " is no longer berserk.");

        monster_die(this, quiet ? KILL_DISMISSED : KILL_RESET, NON_MONSTER);
        break;

    case ENCH_SUBMERGED:
        if (mons_is_wandering(this))
        {
            behaviour = BEH_SEEK;
            behaviour_event(this, ME_EVAL);
        }

        if (you.pos() == this->pos())
        {
            mprf(MSGCH_ERROR, "%s is on the same square as you!",
                 name(DESC_CAP_A).c_str());
        }

        if (you.can_see(this))
        {
            if (!mons_is_safe(this) && is_run_delay(current_delay_action()))
            {
                // Already set somewhere else.
                if (!seen_context.empty())
                    return;

                if (type == MONS_AIR_ELEMENTAL)
                    seen_context = "thin air";
                else if (type == MONS_TRAPDOOR_SPIDER)
                    seen_context = "leaps out";
                else if (!monster_habitable_grid(this, DNGN_FLOOR))
                    seen_context = "bursts forth";
                else
                    seen_context = "surfaces";
            }
            else if (!quiet)
            {
                if (type == MONS_AIR_ELEMENTAL)
                {
                    mprf("%s forms itself from the air!",
                         name(DESC_CAP_A, true).c_str() );
                }
                else if (type == MONS_TRAPDOOR_SPIDER)
                {
                    mprf("%s leaps out from its hiding place under the floor!",
                         name(DESC_CAP_A, true).c_str() );
                }
                else if (crawl_state.arena)
                    mprf("%s surfaces.", name(DESC_CAP_A, true).c_str() );
            }
        }
        else if (mons_near(this)
                 && feat_compatible(grd(pos()), DNGN_DEEP_WATER))
        {
            mpr("Something invisible bursts forth from the water.");
            interrupt_activity(AI_FORCE_INTERRUPT);
        }
        break;

    case ENCH_SOUL_RIPE:
        if (!quiet)
        {
            simple_monster_message(this,
                                   "'s soul is no longer ripe for the taking.");
        }
        break;

    default:
        break;
    }
}

bool monsters::lose_ench_levels(const mon_enchant &e, int lev)
{
    if (!lev)
        return (false);

    if (e.degree <= lev)
    {
        del_ench(e.ench);
        return (true);
    }
    else
    {
        mon_enchant newe(e);
        newe.degree -= lev;
        update_ench(newe);
        return (false);
    }
}

bool monsters::lose_ench_duration(const mon_enchant &e, int dur)
{
    if (!dur)
        return (false);

    if (e.duration <= dur)
    {
        del_ench(e.ench);
        return (true);
    }
    else
    {
        mon_enchant newe(e);
        newe.duration -= dur;
        update_ench(newe);
        return (false);
    }
}

//---------------------------------------------------------------
//
// timeout_enchantments
//
// Update a monster's enchantments when the player returns
// to the level.
//
// Management for enchantments... problems with this are the oddities
// (monster dying from poison several thousands of turns later), and
// game balance.
//
// Consider: Poison/Sticky Flame a monster at range and leave, monster
// dies but can't leave level to get to player (implied game balance of
// the delayed damage is that the monster could be a danger before
// it dies).  This could be fixed by keeping some monsters active
// off level and allowing them to take stairs (a very serious change).
//
// Compare this to the current abuse where the player gets
// effectively extended duration of these effects (although only
// the actual effects only occur on level, the player can leave
// and heal up without having the effect disappear).
//
// This is a simple compromise between the two... the enchantments
// go away, but the effects don't happen off level.  -- bwr
//
//---------------------------------------------------------------
void monsters::timeout_enchantments(int levels)
{
    if (enchantments.empty())
        return;

    const mon_enchant_list ec = enchantments;
    for (mon_enchant_list::const_iterator i = ec.begin();
         i != ec.end(); ++i)
    {
        switch (i->first)
        {
        case ENCH_POISON: case ENCH_ROT: case ENCH_CORONA:
        case ENCH_STICKY_FLAME: case ENCH_ABJ: case ENCH_SHORT_LIVED:
        case ENCH_SLOW: case ENCH_HASTE: case ENCH_MIGHT: case ENCH_FEAR:
        case ENCH_INVIS: case ENCH_CHARM:  case ENCH_SLEEP_WARY:
        case ENCH_SICK:  case ENCH_SLEEPY: case ENCH_PARALYSIS:
        case ENCH_PETRIFYING: case ENCH_PETRIFIED: case ENCH_SWIFT:
        case ENCH_BATTLE_FRENZY: case ENCH_TEMP_PACIF:
        case ENCH_LOWERED_MR: case ENCH_SOUL_RIPE:
            lose_ench_levels(i->second, levels);
            break;

        case ENCH_INSANE:
        case ENCH_BERSERK:
            del_ench(i->first);
            del_ench(ENCH_HASTE, true);
            del_ench(ENCH_MIGHT, true);
            break;

        case ENCH_FATIGUE:
            del_ench(i->first);
            del_ench(ENCH_SLOW);
            break;

        case ENCH_TP:
            del_ench(i->first);
            teleport(true);
            break;

        case ENCH_CONFUSION:
            if (!mons_class_flag(type, M_CONFUSED))
                del_ench(i->first);
            monster_blink(this, true);
            break;

        case ENCH_HELD:
            del_ench(i->first);
            break;

        case ENCH_SLOWLY_DYING:
        {
            const int actdur = speed_to_duration(speed) * levels;
            if (lose_ench_duration(i->first, actdur))
                monster_die(this, KILL_MISC, NON_MONSTER, true);
            break;
        }
        default:
            break;
        }

        if (!alive())
            break;
    }
}

std::string monsters::describe_enchantments() const
{
    std::ostringstream oss;
    for (mon_enchant_list::const_iterator i = enchantments.begin();
         i != enchantments.end(); ++i)
    {
        if (i != enchantments.begin())
            oss << ", ";
        oss << std::string(i->second);
    }
    return (oss.str());
}

// Used to adjust time durations in calc_duration() for monster speed.
static inline int _mod_speed( int val, int speed )
{
    if (!speed)
        speed = 10;
    const int modded = (speed ? (val * 10) / speed : val);
    return (modded? modded : 1);
}

bool monsters::decay_enchantment(const mon_enchant &me, bool decay_degree)
{
    // Faster monsters can wiggle out of the net more quickly.
    const int spd = (me.ench == ENCH_HELD) ? speed :
                                             10;
    const int actdur = speed_to_duration(spd);
    if (lose_ench_duration(me, actdur))
        return (true);

    if (!decay_degree)
        return (false);

    // Decay degree so that higher degrees decay faster than lower
    // degrees, and a degree of 1 does not decay (it expires when the
    // duration runs out).
    const int level = me.degree;
    if (level <= 1)
        return (false);

    const int decay_factor = level * (level + 1) / 2;
    if (me.duration < me.maxduration * (decay_factor - 1) / decay_factor)
    {
        mon_enchant newme = me;
        --newme.degree;
        newme.maxduration = newme.duration;

        if (newme.degree <= 0)
        {
            del_ench(me.ench);
            return (true);
        }
        else
            update_ench(newme);
    }
    return (false);
}

void monsters::apply_enchantment(const mon_enchant &me)
{
    const int spd = 10;
    switch (me.ench)
    {
    case ENCH_INSANE:
        if (decay_enchantment(me))
        {
            simple_monster_message(this, " is no longer in an insane frenzy.");
            del_ench(ENCH_HASTE, true);
            del_ench(ENCH_MIGHT, true);
            const int duration = random_range(70, 130);
            add_ench(mon_enchant(ENCH_FATIGUE, 0, KC_OTHER, duration));
            add_ench(mon_enchant(ENCH_SLOW, 0, KC_OTHER, duration));
        }
        break;

    case ENCH_BERSERK:
        if (decay_enchantment(me))
        {
            simple_monster_message(this, " is no longer berserk.");
            del_ench(ENCH_HASTE, true);
            del_ench(ENCH_MIGHT, true);
            const int duration = random_range(70, 130);
            add_ench(mon_enchant(ENCH_FATIGUE, 0, KC_OTHER, duration));
            add_ench(mon_enchant(ENCH_SLOW, 0, KC_OTHER, duration));
        }
        break;

    case ENCH_FATIGUE:
        if (decay_enchantment(me))
        {
            simple_monster_message(this, " looks more energetic.");
            del_ench(ENCH_SLOW, true);
        }
        break;

    case ENCH_SLOW:
    case ENCH_HASTE:
    case ENCH_SWIFT:
    case ENCH_MIGHT:
    case ENCH_FEAR:
    case ENCH_PARALYSIS:
    case ENCH_TEMP_PACIF:
    case ENCH_PETRIFYING:
    case ENCH_PETRIFIED:
    case ENCH_SICK:
    case ENCH_CORONA:
    case ENCH_ABJ:
    case ENCH_CHARM:
    case ENCH_SLEEP_WARY:
    case ENCH_LOWERED_MR:
    case ENCH_SOUL_RIPE:
        decay_enchantment(me);
        break;

    case ENCH_BATTLE_FRENZY:
        decay_enchantment(me, false);
        break;

    case ENCH_AQUATIC_LAND:
        // Aquatic monsters lose hit points every turn they spend on dry land.
        ASSERT(mons_habitat(this) == HT_WATER
               && !feat_is_watery( grd(pos()) ));

        // Zombies don't take damage from flopping about on land.
        if (mons_is_zombified(this))
            break;

        // We don't have a reasonable agent to give.
        // Don't clean up the monster in order to credit properly.
        hurt(NULL, 1 + random2(5), BEAM_NONE, false);

        // Credit the kill.
        if (hit_points < 1)
        {
            monster_die(this, me.killer(), me.kill_agent());
            break;
        }
        break;

    case ENCH_HELD:
    {
        if (mons_is_stationary(this) || cannot_act() || asleep())
        {
            break;
        }

        int net = get_trapping_net(this->pos(), true);

        if (net == NON_ITEM) // Really shouldn't happen!
        {
            del_ench(ENCH_HELD);
            break;
        }

        // Handled in handle_pickup().
        if (mons_eats_items(this))
            break;

        // The enchantment doubles as the durability of a net
        // the more corroded it gets, the more easily it will break.
        const int hold = mitm[net].plus; // This will usually be negative.
        const int mon_size = body_size(PSIZE_BODY);

        // Smaller monsters can escape more quickly.
        if (mon_size < random2(SIZE_BIG)  // BIG = 5
            && !berserk() && type != MONS_DANCING_WEAPON)
        {
            if (mons_near(this) && !visible_to(&you))
                mpr("Something wriggles in the net.");
            else
                simple_monster_message(this, " struggles to escape the net.");

            // Confused monsters have trouble finding the exit.
            if (has_ench(ENCH_CONFUSION) && !one_chance_in(5))
                break;

            decay_enchantment(me, 2*(NUM_SIZE_LEVELS - mon_size) - hold);

            // Frayed nets are easier to escape.
            if (mon_size <= -(hold-1)/2)
                decay_enchantment(me, (NUM_SIZE_LEVELS - mon_size));
        }
        else // Large (and above) monsters always thrash the net and destroy it
        {    // e.g. ogre, large zombie (large); centaur, naga, hydra (big).

            if (mons_near(this) && !visible_to(&you))
                mpr("Something wriggles in the net.");
            else
                simple_monster_message(this, " struggles against the net.");

            // Confused monsters more likely to struggle without result.
            if (has_ench(ENCH_CONFUSION) && one_chance_in(3))
                break;

            // Nets get destroyed more quickly for larger monsters
            // and if already strongly frayed.
            int damage = 0;

            // tiny: 1/6, little: 2/5, small: 3/4, medium and above: always
            if (x_chance_in_y(mon_size + 1, SIZE_GIANT - mon_size))
                damage++;

            // Handled specially to make up for its small size.
            if (type == MONS_DANCING_WEAPON)
            {
                damage += one_chance_in(3);

                if (can_cut_meat(mitm[inv[MSLOT_WEAPON]]))
                    damage++;
            }


            // Extra damage for large (50%) and big (always).
            if (mon_size == SIZE_BIG || mon_size == SIZE_LARGE && coinflip())
                damage++;

            // overall damage per struggle:
            // tiny   -> 1/6
            // little -> 2/5
            // small  -> 3/4
            // medium -> 1
            // large  -> 1,5
            // big    -> 2

            // extra damage if already damaged
            if (random2(body_size(PSIZE_BODY) - hold + 1) >= 4)
                damage++;

            // Berserking doubles damage dealt.
            if (berserk())
                damage *= 2;

            // Faster monsters can damage the net more often per
            // time period.
            if (speed != 0)
                damage = div_rand_round(damage * speed, spd);

            mitm[net].plus -= damage;

            if (mitm[net].plus < -7)
            {
                if (mons_near(this))
                {
                    if (visible_to(&you))
                    {
                        mprf("The net rips apart, and %s comes free!",
                             name(DESC_NOCAP_THE).c_str());
                    }
                    else
                    {
                        mpr("All of a sudden the net rips apart!");
                    }
                }
                destroy_item(net);

                del_ench(ENCH_HELD, true);
            }

        }
        break;
    }
    case ENCH_CONFUSION:
        if (!mons_class_flag(type, M_CONFUSED))
            decay_enchantment(me);
        break;

    case ENCH_INVIS:
        if (!mons_class_flag(type, M_INVIS))
            decay_enchantment(me);
        break;

    case ENCH_SUBMERGED:
    {
        // Not even air elementals unsubmerge into clouds.
        if (env.cgrid(pos()) != EMPTY_CLOUD)
            break;

        // Air elementals are a special case, as their submerging in air
        // isn't up to choice. - bwr
        if (type == MONS_AIR_ELEMENTAL)
        {
            heal(1, one_chance_in(5));

            if (one_chance_in(5))
                del_ench(ENCH_SUBMERGED);

            break;
        }

        // Now we handle the others:
        const dungeon_feature_type grid = grd(pos());

        // Badly injured monsters prefer to stay submerged...
        // electric eels and lava snakes have ranged attacks
        // and are more likely to surface.  -- bwr
        if (!monster_can_submerge(this, grid))
            del_ench(ENCH_SUBMERGED); // forced to surface
        else if (hit_points <= max_hit_points / 2)
            break;
        else if (type == MONS_TRAPDOOR_SPIDER)
        {
            // This should probably never happen.
            if (!mons_is_lurking(this))
                del_ench(ENCH_SUBMERGED);
            break;
        }
        else if (((type == MONS_ELECTRIC_EEL || type == MONS_LAVA_SNAKE || type == MONS_KRAKEN)
                  && (one_chance_in(50) || (mons_near(this)
                                            && hit_points == max_hit_points
                                            && !one_chance_in(10))))
                 || one_chance_in(200)
                 || (mons_near(this)
                     && hit_points == max_hit_points
                     && !one_chance_in(5)))
        {
            del_ench(ENCH_SUBMERGED);
        }
        break;
    }
    case ENCH_POISON:
    {
        const int poisonval = me.degree;
        int dam = (poisonval >= 4) ? 1 : 0;

        if (coinflip())
            dam += roll_dice(1, poisonval + 1);

        if (res_poison() < 0)
            dam += roll_dice(2, poisonval) - 1;

        if (dam > 0)
        {
            // We don't have a reasonable agent to give.
            // Don't clean up the monster in order to credit properly.
            hurt(NULL, dam, BEAM_POISON, false);

#if DEBUG_DIAGNOSTICS
            // For debugging, we don't have this silent.
            simple_monster_message(this, " takes poison damage.",
                                   MSGCH_DIAGNOSTICS);
            mprf(MSGCH_DIAGNOSTICS, "poison damage: %d", dam);
#endif

            // Credit the kill.
            if (hit_points < 1)
            {
                monster_die(this, me.killer(), me.kill_agent());
                break;
            }
        }

        decay_enchantment(me, true);
        break;
    }
    case ENCH_ROT:
    {
        if (hit_points > 1 && one_chance_in(3))
        {
            hurt(NULL, 1); // nonlethal so we don't care about agent
            if (hit_points < max_hit_points && coinflip())
                --max_hit_points;
        }

        decay_enchantment(me, true);
        break;
    }

    // Assumption: monsters::res_fire has already been checked.
    case ENCH_STICKY_FLAME:
    {
        if (feat_is_watery(grd(pos())))
        {
            if (mons_near(this) && visible_to(&you))
                mprf("The flames covering %s go out.",
                     this->name(DESC_NOCAP_THE, false).c_str());
            del_ench(ENCH_STICKY_FLAME);
            break;
        }
        int dam = resist_adjust_damage(this, BEAM_FIRE, res_fire(),
                                       roll_dice(2, 4) - 1);

        if (dam > 0)
        {
            simple_monster_message(this, " burns!");
            // We don't have a reasonable agent to give.
            // Don't clean up the monster in order to credit properly.
            hurt(NULL, dam, BEAM_NAPALM, false);

            dprf("sticky flame damage: %d", dam);

            // Credit the kill.
            if (hit_points < 1)
            {
                monster_die(this, me.killer(), me.kill_agent());
                break;
            }
        }

        decay_enchantment(me, true);
        break;
    }

    case ENCH_SHORT_LIVED:
        // This should only be used for ball lightning -- bwr
        if (decay_enchantment(me))
            hit_points = -1;
        break;

    case ENCH_SLOWLY_DYING:
        // If you are no longer dying, you must be dead.
        if (decay_enchantment(me))
        {
            if (you.see_cell(position))
            {
                mprf("A nearby %s withers and dies.",
                     this->name(DESC_PLAIN, false).c_str());
            }

            monster_die(this, KILL_MISC, NON_MONSTER, true);
        }
        break;

    case ENCH_SPORE_PRODUCTION:

        // Reduce the timer, if that means we lose the enchantment then
        // spawn a spore and re-add the enchantment
        if(decay_enchantment(me))
        {
            // Search for an open adjacent square to place a spore on
            int idx[] = {0, 1, 2, 3, 4, 5, 6, 7};
            std::random_shuffle(idx, idx + 8);

            bool re_add = true;

            for (unsigned i = 0; i < 8; ++i)
            {
                coord_def adjacent = this->pos() + Compass[idx[i]];

                if (mons_class_can_pass(MONS_GIANT_SPORE, env.grid(adjacent))
                                        && !actor_at(adjacent))
                {
                    beh_type created_behavior = SAME_ATTITUDE(this);

                    int rc = create_monster(mgen_data(MONS_GIANT_SPORE,
                                                      created_behavior,
                                                      this,
                                                      0,
                                                      0,
                                                      adjacent,
                                                      MHITNOT,
                                                      MG_FORCE_PLACE));

                    if (rc != -1)
                    {
                        env.mons[rc].behaviour = BEH_WANDER;
                        env.mons[rc].number = 20;

                        if (you.see_cell(adjacent) && you.see_cell(pos()))
                            mpr("A ballistomycete spawns a giant spore.");

                        // Decrease the count and maybe become inactive
                        // again
                        if (this->number)
                        {
                            this->number--;
                            if (this->number == 0)
                            {
                                this->colour = MAGENTA;
                                this->del_ench(ENCH_SPORE_PRODUCTION);
                                re_add = false;
                            }
                        }

                    }
                    break;
                }
            }
            // Re-add the enchantment (this resets the spore production
            // timer).
            if (re_add)
                this->add_ench(ENCH_SPORE_PRODUCTION);
        }

        break;

    case ENCH_GLOWING_SHAPESHIFTER: // This ench never runs out!
        // Number of actions is fine for shapeshifters.  Don't change
        // shape while taking the stairs because monster_polymorph() has
        // an assert about it. -cao
        if (!(this->flags & MF_TAKING_STAIRS) && !asleep()
            && (type == MONS_GLOWING_SHAPESHIFTER
                || one_chance_in(4)))
        {
            monster_polymorph(this, RANDOM_MONSTER);
        }
        break;

    case ENCH_SHAPESHIFTER:         // This ench never runs out!
        if (!(this->flags & MF_TAKING_STAIRS) && !asleep()
            && (type == MONS_SHAPESHIFTER
                || x_chance_in_y(1000 / (15 * hit_dice / 5), 1000)))
        {
            monster_polymorph(this, RANDOM_MONSTER);
        }
        break;

    case ENCH_TP:
        if (decay_enchantment(me, true))
            monster_teleport(this, true);
        break;

    case ENCH_SLEEPY:
        del_ench(ENCH_SLEEPY);
        break;

    case ENCH_EAT_ITEMS:
         break;

    default:
        break;
    }
}

void monsters::mark_summoned(int longevity, bool mark_items, int summon_type)
{
    add_ench( mon_enchant(ENCH_ABJ, longevity) );
    if (summon_type != 0)
        add_ench( mon_enchant(ENCH_SUMMON, summon_type, KC_OTHER, INT_MAX) );

    if (mark_items)
    {
        for (int i = 0; i < NUM_MONSTER_SLOTS; ++i)
        {
            const int item = inv[i];
            if (item != NON_ITEM)
                mitm[item].flags |= ISFLAG_SUMMONED;
        }
    }
}

bool monsters::is_summoned(int* duration, int* summon_type) const
{
    const mon_enchant abj = get_ench(ENCH_ABJ);
    if (abj.ench == ENCH_NONE)
    {
        if (duration != NULL)
            *duration = -1;
        if (summon_type != NULL)
            *summon_type = 0;

        return (false);
    }
    if (duration != NULL)
        *duration = abj.duration;

    const mon_enchant summ = get_ench(ENCH_SUMMON);
    if (summ.ench == ENCH_NONE)
    {
        if (summon_type != NULL)
            *summon_type = 0;

        return (true);
    }
    if (summon_type != NULL)
        *summon_type = summ.degree;

    switch (summ.degree)
    {
    // Temporarily dancing weapons are really there.
    case SPELL_TUKIMAS_DANCE:

    // A corpse/skeleton which was temporarily animated.
    case SPELL_ANIMATE_DEAD:
    case SPELL_ANIMATE_SKELETON:

    // Fire vortices are made from real fire.
    case SPELL_FIRE_STORM:

    // Clones aren't really summoned (though their equipment might be).
    case MON_SUMM_CLONE:

    // Nor are body parts.
    case SPELL_KRAKEN_TENTACLES:

    // Some object which was animated, and thus not really summoned.
    case MON_SUMM_ANIMATE:
        return (false);
    }

    return (true);
}

void monsters::apply_enchantments()
{
    if (enchantments.empty())
        return;

    // The ordering in enchant_type makes sure that "super-enchantments"
    // like berserk time out before their parts.
    const mon_enchant_list ec = enchantments;
    for (mon_enchant_list::const_iterator i = ec.begin(); i != ec.end(); ++i)
    {
        apply_enchantment(i->second);
        if (!alive())
            break;
    }
}

void monsters::scale_hp(int num, int den)
{
    hit_points     = hit_points * num / den;
    max_hit_points = max_hit_points * num / den;

    if (hit_points < 1)
        hit_points = 1;
    if (max_hit_points < 1)
        max_hit_points = 1;
    if (hit_points > max_hit_points)
        hit_points = max_hit_points;
}

kill_category monsters::kill_alignment() const
{
    return (friendly() ? KC_FRIENDLY : KC_OTHER);
}

bool monsters::sicken(int amount)
{
    if (res_rotting() || (amount /= 2) < 1)
        return (false);

    if (!has_ench(ENCH_SICK) && you.can_see(this))
    {
        // Yes, could be confused with poisoning.
        mprf("%s looks sick.", name(DESC_CAP_THE).c_str());
    }

    add_ench(mon_enchant(ENCH_SICK, 0, KC_OTHER, amount * 10));

    return (true);
}

// Recalculate movement speed.
void monsters::fix_speed()
{
    speed = mons_real_base_speed(type);

    if (has_ench(ENCH_HASTE))
        speed *= 2;
    else if (has_ench(ENCH_SLOW))
        speed /= 2;
}

// Check speed and speed_increment sanity.
void monsters::check_speed()
{
    // FIXME: If speed is borked, recalculate.  Need to figure out how
    // speed is getting borked.
    if (speed < 0 || speed > 130)
    {
#ifdef DEBUG_DIAGNOSTICS
        mprf(MSGCH_DIAGNOSTICS,
             "Bad speed: %s, spd: %d, spi: %d, hd: %d, ench: %s",
             name(DESC_PLAIN).c_str(),
             speed, speed_increment, hit_dice,
             describe_enchantments().c_str());
#endif

        fix_speed();

#ifdef DEBUG_DIAGNOSTICS
        mprf(MSGCH_DIAGNOSTICS, "Fixed speed for %s to %d",
             name(DESC_PLAIN).c_str(), speed);
#endif
    }

    if (speed_increment < 0)
        speed_increment = 0;

    if (speed_increment > 200)
    {
#ifdef DEBUG_DIAGNOSTICS
        mprf(MSGCH_DIAGNOSTICS,
             "Clamping speed increment on %s: %d",
             name(DESC_PLAIN).c_str(), speed_increment);
#endif
        speed_increment = 140;
    }
}

actor *monsters::get_foe() const
{
    if (foe == MHITNOT)
        return (NULL);
    else if (foe == MHITYOU)
        return (friendly() ? NULL : &you);

    // Must be a monster!
    monsters *my_foe = &menv[foe];
    return (my_foe->alive()? my_foe : NULL);
}

int monsters::foe_distance() const
{
    const actor *afoe = get_foe();
    return (afoe ? pos().distance_from(afoe->pos())
                 : INFINITE_DISTANCE);
}

bool monsters::can_go_berserk() const
{
    if (holiness() != MH_NATURAL || type == MONS_KRAKEN_TENTACLE)
        return (false);

    if (mons_intel(this) == I_PLANT)
        return (false);

    if (berserk() || has_ench(ENCH_FATIGUE))
        return (false);

    // If we have no melee attack, going berserk is pointless.
    const mon_attack_def attk = mons_attack_spec(this, 0);
    if (attk.type == AT_NONE || attk.damage == 0)
        return (false);

    return (true);
}

bool monsters::frenzied() const
{
    return (has_ench(ENCH_INSANE));
}

bool monsters::berserk() const
{
    return (has_ench(ENCH_BERSERK) || has_ench(ENCH_INSANE));
}

bool monsters::needs_berserk(bool check_spells) const
{
    if (!can_go_berserk())
        return (false);

    if (has_ench(ENCH_HASTE) || has_ench(ENCH_TP))
        return (false);

    if (foe_distance() > 3)
        return (false);

    if (check_spells)
    {
        for (int i = 0; i < NUM_MONSTER_SPELL_SLOTS; ++i)
        {
            const int spell = spells[i];
            if (spell != SPELL_NO_SPELL && spell != SPELL_BERSERKER_RAGE)
                return (false);
        }
    }

    return (true);
}

bool monsters::can_see_invisible() const
{
    if (mons_is_ghost_demon(this->type))
        return (this->ghost->see_invis);
    else if (mons_class_flag(this->type, M_SEE_INVIS))
        return (true);
    else if (scan_mon_inv_randarts(this, ARTP_EYESIGHT) > 0)
        return (true);
    return (false);
}

bool monsters::invisible() const
{
    return (has_ench(ENCH_INVIS) && !backlit());
}

bool monsters::visible_to(const actor *looker) const
{
    bool vis = !invisible() || looker->can_see_invisible();
    return (vis && (this == looker || !has_ench(ENCH_SUBMERGED)));
}

bool monsters::mon_see_cell(const coord_def& p, bool reach) const
{
    if (p == pos())
        return (true);
    if (distance(pos(), p) > LOS_RADIUS * LOS_RADIUS + 1)
        return (false);

    dungeon_feature_type max_disallowed = DNGN_MAXOPAQUE;
    if (reach)
        max_disallowed = DNGN_MAX_NONREACH;

    // XXX: Ignoring clouds for now.
    return (!num_feats_between(pos(), p, DNGN_UNSEEN, max_disallowed,
                               true, true));
}

bool monsters::near_foe() const
{
    const actor *afoe = get_foe();
    return (afoe && see_cell(afoe->pos()));
}

bool monsters::can_mutate() const
{
    return (holiness() == MH_NATURAL || holiness() == MH_PLANT);
}

bool monsters::can_safely_mutate() const
{
    return (can_mutate());
}

bool monsters::can_bleed() const
{
    return (mons_has_blood(type));
}

bool monsters::mutate()
{
    if (!can_mutate())
        return (false);

    // Polymorphing a (very) ugly thing will mutate it into a different
    // (very) ugly thing.
    if (type == MONS_UGLY_THING || type == MONS_VERY_UGLY_THING)
    {
        ugly_thing_mutate(this);
        return (true);
    }

    // Polymorphing a shapeshifter will make it revert to its original
    // form.
    if (this->has_ench(ENCH_GLOWING_SHAPESHIFTER))
        return (monster_polymorph(this, MONS_GLOWING_SHAPESHIFTER));
    if (this->has_ench(ENCH_SHAPESHIFTER))
        return (monster_polymorph(this, MONS_SHAPESHIFTER));

    return (monster_polymorph(this, RANDOM_MONSTER));
}

static bool _mons_is_icy(int mc)
{
    return (mc == MONS_ICE_BEAST
            || mc == MONS_SIMULACRUM_SMALL
            || mc == MONS_SIMULACRUM_LARGE
            || mc == MONS_ICE_STATUE);
}

bool monsters::is_icy() const
{
    return (_mons_is_icy(type));
}

static bool _mons_is_fiery(int mc)
{
    return (mc == MONS_FIRE_VORTEX
            || mc == MONS_FIRE_ELEMENTAL
            || mc == MONS_FLAMING_CORPSE
            || mc == MONS_EFREET
            || mc == MONS_AZRAEL
            || mc == MONS_LAVA_WORM
            || mc == MONS_LAVA_FISH
            || mc == MONS_LAVA_SNAKE
            || mc == MONS_SALAMANDER
            || mc == MONS_MOLTEN_GARGOYLE
            || mc == MONS_ORB_OF_FIRE);
}

bool monsters::is_fiery() const
{
    return (_mons_is_fiery(type));
}

bool monsters::has_action_energy() const
{
    return (speed_increment >= 80);
}

void monsters::check_redraw(const coord_def &old) const
{
    const bool see_new = you.see_cell(pos());
    const bool see_old = you.see_cell(old);
    if ((see_new || see_old) && !view_update())
    {
        if (see_new)
            view_update_at(pos());
        if (see_old)
            view_update_at(old);
        update_screen();
    }
}

void monsters::apply_location_effects(const coord_def &oldpos,
                                      killer_type killer,
                                      int killernum)
{
    if (oldpos != pos())
        dungeon_events.fire_position_event(DET_MONSTER_MOVED, pos());

    if (alive() && mons_habitat(this) == HT_WATER
        && !feat_is_watery( grd(pos()) ) && !has_ench(ENCH_AQUATIC_LAND))
    {
        add_ench(ENCH_AQUATIC_LAND);
    }

    if (alive() && has_ench(ENCH_AQUATIC_LAND))
    {
        if (!feat_is_watery( grd(pos()) ))
            simple_monster_message(this, " flops around on dry land!");
        else if (!feat_is_watery( grd(oldpos) ))
        {
            simple_monster_message(this, " dives back into the water!");
            del_ench(ENCH_AQUATIC_LAND);
        }
        // This may have been called via dungeon_terrain_changed instead
        // of by the monster moving move, in that case grd(oldpos) will
        // be the current position that became watery.
        else
            del_ench(ENCH_AQUATIC_LAND);
    }

    // Monsters stepping on traps:
    trap_def* ptrap = find_trap(pos());
    if (ptrap)
        ptrap->trigger(*this);

    if (alive())
        mons_check_pool(this, pos(), killer, killernum);

    if (alive() && has_ench(ENCH_SUBMERGED)
        && (!monster_can_submerge(this, grd(pos()))
            || type == MONS_TRAPDOOR_SPIDER))
    {
        del_ench(ENCH_SUBMERGED);

        if (type == MONS_TRAPDOOR_SPIDER)
            behaviour_event(this, ME_EVAL);
    }

    unsigned long &prop = env.pgrid(pos());

    if (prop & FPROP_BLOODY)
    {
        monster_type genus = mons_genus(type);

        if (genus == MONS_JELLY || genus == MONS_GIANT_SLUG)
        {
            prop &= ~FPROP_BLOODY;
            if (you.see_cell(pos()) && !visible_to(&you))
            {
               std::string desc =
                   feature_description(pos(), false, DESC_NOCAP_THE, false);
               mprf("The bloodstain on %s disappears!", desc.c_str());
            }
        }
    }
}

bool monsters::move_to_pos(const coord_def &newpos)
{
    if (actor_at(newpos))
        return (false);

    // Clear old cell pointer.
    mgrd(pos()) = NON_MONSTER;

    // Set monster x,y to new value.
    moveto(newpos);

    // Set new monster grid pointer to this monster.
    mgrd(newpos) = mindex();

    return (true);
}

// Returns true if the trap should be revealed to the player.
bool monsters::do_shaft()
{
    if (!is_valid_shaft_level())
        return (false);

    // Handle instances of do_shaft() being invoked magically when
    // the monster isn't standing over a shaft.
    if (get_trap_type(this->pos()) != TRAP_SHAFT)
    {
        switch (grd(pos()))
        {
        case DNGN_FLOOR:
        case DNGN_OPEN_DOOR:
        case DNGN_TRAP_MECHANICAL:
        case DNGN_TRAP_MAGICAL:
        case DNGN_TRAP_NATURAL:
        case DNGN_UNDISCOVERED_TRAP:
        case DNGN_ENTER_SHOP:
            break;

        default:
            return (false);
        }

        if (airborne() || total_weight() == 0)
        {
            if (mons_near(this))
            {
                if (visible_to(&you))
                {
                    mprf("A shaft briefly opens up underneath %s!",
                         name(DESC_NOCAP_THE).c_str());
                }
                else
                    mpr("A shaft briefly opens up in the floor!");
            }

            handle_items_on_shaft(this->pos(), false);
            return (false);
        }
    }

    level_id lev = shaft_dest(false);

    if (lev == level_id::current())
        return (false);

    // If a pacified monster is leaving the level via a shaft trap, and
    // has reached its goal, handle it here.
    if (!pacified())
        set_transit(lev);

    const bool reveal =
        simple_monster_message(this, " falls through a shaft!");

    handle_items_on_shaft(this->pos(), false);

    // Monster is no longer on this level.
    destroy_inventory();
    monster_cleanup(this);

    return (reveal);
}

void monsters::hibernate(int)
{
    if (!can_hibernate())
        return;

    behaviour = BEH_SLEEP;
    add_ench(ENCH_SLEEPY);
    add_ench(ENCH_SLEEP_WARY);
}

void monsters::put_to_sleep(actor *attacker, int strength)
{
    if (has_ench(ENCH_SLEEPY))
        return;

    behaviour = BEH_SLEEP;
    add_ench(ENCH_SLEEPY);
}

void monsters::check_awaken(int)
{
    // XXX
}

const monsterentry *monsters::find_monsterentry() const
{
    return (type == MONS_NO_MONSTER || type == MONS_PROGRAM_BUG) ? NULL
                                                    : get_monster_data(type);
}

monster_type monsters::get_mislead_type() const
{
    if (props.exists("mislead_as"))
        return static_cast<monster_type>(props["mislead_as"].get_short());
    else
        return type;
}

int monsters::action_energy(energy_use_type et) const
{
    bool swift = has_ench(ENCH_SWIFT);

    if (const monsterentry *me = find_monsterentry())
    {
        const mon_energy_usage &mu = me->energy_usage;
        switch (et)
        {
        case EUT_MOVE:    return mu.move - (swift ? 2 : 0);
        case EUT_SWIM:
            // [ds] Amphibious monsters get a significant speed boost
            // when swimming, as discussed with dpeg. We do not
            // distinguish between amphibians that favour land
            // (HT_AMPHIBIOUS_LAND, such as hydras) and those that
            // favour water (HT_AMPHIBIOUS_WATER, such as merfolk), but
            // that's something we can think about.
            if (mons_amphibious(this))
                return div_rand_round(mu.swim * 7, 10) - (swift ? 2 : 0);
            else
                return mu.swim - (swift ? 2 : 0);
        case EUT_MISSILE: return mu.missile;
        case EUT_ITEM:    return mu.item;
        case EUT_SPECIAL: return mu.special;
        case EUT_SPELL:   return mu.spell;
        case EUT_ATTACK:  return mu.attack;
        case EUT_PICKUP:  return mu.pickup_percent;
        }
    }
    return 10;
}

void monsters::lose_energy(energy_use_type et, int div, int mult)
{
    int energy_loss  = div_round_up(mult * action_energy(et), div);
    if (has_ench(ENCH_PETRIFYING))
    {
        energy_loss *= 3;
        energy_loss /= 2;
    }

    speed_increment -= energy_loss;
}

bool monsters::can_drink_potion(potion_type ptype) const
{
    if (mons_class_is_stationary(type))
        return (false);

    if (mons_itemuse(this) < MONUSE_STARTING_EQUIPMENT)
        return (false);

    // These monsters cannot drink.
    if (mons_is_skeletal(type) || mons_is_insubstantial(type)
        || mons_species() == MONS_LICH || mons_genus(type) == MONS_MUMMY
        || type == MONS_GASTRONOK)
    {
        return (false);
    }

    switch (ptype)
    {
        case POT_HEALING:
        case POT_HEAL_WOUNDS:
            return (holiness() != MH_NONLIVING
                    && holiness() != MH_PLANT);
        case POT_BLOOD:
        case POT_BLOOD_COAGULATED:
            return (mons_species() == MONS_VAMPIRE);
        case POT_SPEED:
        case POT_MIGHT:
        case POT_BERSERK_RAGE:
        case POT_INVISIBILITY:
            // If there are any item using monsters that are permanently
            // invisible, this might have to be restricted.
            return (true);
        default:
            break;
    }

    return (false);
}

bool monsters::should_drink_potion(potion_type ptype) const
{
    switch (ptype)
    {
    case POT_HEALING:
        return (hit_points <= max_hit_points / 2)
                || has_ench(ENCH_POISON)
                || has_ench(ENCH_SICK)
                || has_ench(ENCH_CONFUSION)
                || has_ench(ENCH_ROT);
    case POT_HEAL_WOUNDS:
        return (hit_points <= max_hit_points / 2);
    case POT_BLOOD:
    case POT_BLOOD_COAGULATED:
        return (hit_points <= max_hit_points / 2);
    case POT_SPEED:
        return (!has_ench(ENCH_HASTE));
    case POT_MIGHT:
        return (!has_ench(ENCH_MIGHT) && foe_distance() <= 2);
    case POT_BERSERK_RAGE:
        // this implies !berserk()
        return (!has_ench(ENCH_MIGHT) && !has_ench(ENCH_HASTE)
                && needs_berserk());
    case POT_INVISIBILITY:
        // We're being nice: friendlies won't go invisible if the player
        // won't be able to see them.
        return (!has_ench(ENCH_INVIS)
                && (you.can_see_invisible(false) || !friendly()));
    default:
        break;
    }

    return (false);
}

// Return the ID status gained.
item_type_id_state_type monsters::drink_potion_effect(potion_type ptype)
{
    simple_monster_message(this, " drinks a potion.");

    item_type_id_state_type ident = ID_MON_TRIED_TYPE;

    switch (ptype)
    {
    case POT_HEALING:
    {
        heal(5 + random2(7));
        simple_monster_message(this, " is healed!");

        const enchant_type cured_enchants[] = {
            ENCH_POISON, ENCH_SICK, ENCH_CONFUSION, ENCH_ROT
        };

        // We can differentiate healing and heal wounds (and blood,
        // for vampires) by seeing if any status ailments are cured.
        for (unsigned int i = 0; i < ARRAYSZ(cured_enchants); ++i)
            if (del_ench(cured_enchants[i]))
                ident = ID_KNOWN_TYPE;
    }
    break;

    case POT_HEAL_WOUNDS:
        heal(10 + random2avg(28, 3));
        simple_monster_message(this, " is healed!");
        break;

    case POT_BLOOD:
    case POT_BLOOD_COAGULATED:
        if (mons_species() == MONS_VAMPIRE)
        {
            heal(10 + random2avg(28, 3));
            simple_monster_message(this, " is healed!");
        }
        break;

    case POT_SPEED:
        if (enchant_monster_with_flavour(this, this, BEAM_HASTE))
            ident = ID_KNOWN_TYPE;
        break;

    case POT_INVISIBILITY:
        if (enchant_monster_with_flavour(this, this, BEAM_INVISIBILITY))
            ident = ID_KNOWN_TYPE;
        break;

    case POT_MIGHT:
        if (enchant_monster_with_flavour(this, this, BEAM_MIGHT))
            ident = ID_KNOWN_TYPE;
        break;

    case POT_BERSERK_RAGE:
        if (enchant_monster_with_flavour(this, this, BEAM_BERSERK))
            ident = ID_KNOWN_TYPE;
        break;

    default:
        break;
    }

    return (ident);
}

void monsters::react_to_damage(int damage, beam_type flavour, kill_category whose)
{
    if (type == MONS_SIXFIRHY && flavour == BEAM_ELECTRICITY)
    {
        if (!alive()) // overcharging is deadly
            simple_monster_message(this, " explodes in an explosion of sparks!");
        else if (heal(damage*2, false))
            simple_monster_message(this, " seems to be charged up!");
        return;
    }

    if (!alive())
        return;

    // The royal jelly objects to taking damage and will SULK. :-)
    if (type == MONS_ROYAL_JELLY)
    {
        int lobes = hit_points / 12;
        int oldlobes = (hit_points + damage) / 12;

        if (lobes == oldlobes)
            return;

        mon_acting mact(this);

        const int tospawn = oldlobes - lobes;
#ifdef DEBUG_DIAGNOSTICS
        mprf(MSGCH_DIAGNOSTICS, "Trying to spawn %d jellies.", tospawn);
#endif
        const beh_type beha = SAME_ATTITUDE(this);
        int spawned = 0;
        for (int i = 0; i < tospawn; ++i)
        {
            const monster_type jelly = royal_jelly_ejectable_monster();
            coord_def jpos = find_newmons_square_contiguous(jelly, pos());
            if (!in_bounds(jpos))
                continue;

            const int nmons = mons_place(
                                  mgen_data(jelly, beha, this, 0, 0,
                                            jpos, foe, 0, god));

            if (nmons != -1 && nmons != NON_MONSTER)
            {
                // Don't allow milking the royal jelly.
                menv[nmons].flags |= MF_NO_REWARD;
                spawned++;
            }
        }

        const bool needs_message = spawned && mons_near(this)
                                   && visible_to(&you);

        if (needs_message)
        {
            const std::string monnam = name(DESC_CAP_THE);
            mprf("%s shudders%s.", monnam.c_str(),
                 spawned >= 5 ? " alarmingly" :
                 spawned >= 3 ? " violently" :
                 spawned > 1 ? " vigorously" : "");

            if (spawned == 1)
                mprf("%s spits out another jelly.", monnam.c_str());
            else
            {
                mprf("%s spits out %s more jellies.",
                     monnam.c_str(),
                     number_in_words(spawned).c_str());
            }
        }
    }
    else if (type == MONS_KRAKEN_TENTACLE && flavour != BEAM_TORMENT_DAMAGE)
    {
        if (!invalid_monster_index(number)
            && mons_base_type(&menv[number]) == MONS_KRAKEN)
        {
            menv[number].hurt(&you, damage, flavour);

            // We could be removed, undo this or certain post-hit effects will cry.
            if (invalid_monster(this))
            {
                type = MONS_KRAKEN_TENTACLE;
                hit_points = -1;
            }
        }
    }
    else if (type == MONS_BUSH && flavour == BEAM_FIRE
             && damage>8 && x_chance_in_y(damage, 20))
    {
        place_cloud(CLOUD_FIRE, pos(), 20+random2(15), whose, 5);
    }
}

/////////////////////////////////////////////////////////////////////////
// mon_enchant

static const char *enchant_names[] =
{
    "none", "berserk", "haste", "might", "fatigue", "slow", "fear",
    "confusion", "invis", "poison", "rot", "summon", "abj", "corona",
    "charm", "sticky_flame", "glowing_shapeshifter", "shapeshifter", "tp",
    "sleep_wary", "submerged", "short_lived", "paralysis", "sick",
    "sleepy", "held", "battle_frenzy", "temp_pacif", "petrifying",
    "petrified", "lowered_mr", "soul_ripe", "slowly_dying", "eat_items",
    "aquatic_land", "spore_production", "slouch", "swift", "tide",
    "insane", "buggy"
};

static const char *_mons_enchantment_name(enchant_type ench)
{
    COMPILE_CHECK(ARRAYSZ(enchant_names) == NUM_ENCHANTMENTS+1, c1);

    if (ench > NUM_ENCHANTMENTS)
        ench = NUM_ENCHANTMENTS;

    return (enchant_names[ench]);
}

mon_enchant::mon_enchant(enchant_type e, int deg, kill_category whose,
                         int dur)
    : ench(e), degree(deg), duration(dur), maxduration(0), who(whose)
{
}

mon_enchant::operator std::string () const
{
    return make_stringf("%s (%d:%d%s)",
                        _mons_enchantment_name(ench),
                        degree,
                        duration,
                        kill_category_desc(who));
}

const char *mon_enchant::kill_category_desc(kill_category k) const
{
    return (k == KC_YOU?      " you" :
            k == KC_FRIENDLY? " pet" : "");
}

void mon_enchant::merge_killer(kill_category k)
{
    who = who < k? who : k;
}

void mon_enchant::cap_degree()
{
    // Sickness is not capped.
    if (ench == ENCH_SICK)
        return;

    // Hard cap to simulate old enum behaviour, we should really throw this
    // out entirely.
    const int max = ench == ENCH_ABJ? 6 : 4;
    if (degree > max)
        degree = max;
}

mon_enchant &mon_enchant::operator += (const mon_enchant &other)
{
    if (ench == other.ench)
    {
        degree   += other.degree;
        cap_degree();
        duration += other.duration;
        merge_killer(other.who);
    }
    return (*this);
}

mon_enchant mon_enchant::operator + (const mon_enchant &other) const
{
    mon_enchant tmp(*this);
    tmp += other;
    return (tmp);
}

killer_type mon_enchant::killer() const
{
    return (who == KC_YOU      ? KILL_YOU :
            who == KC_FRIENDLY ? KILL_MON
                               : KILL_MISC);
}

int mon_enchant::kill_agent() const
{
    return (who == KC_FRIENDLY? ANON_FRIENDLY_MONSTER : 0);
}

int mon_enchant::modded_speed(const monsters *mons, int hdplus) const
{
    return (_mod_speed(mons->hit_dice + hdplus, mons->speed));
}

int mon_enchant::calc_duration(const monsters *mons,
                               const mon_enchant *added) const
{
    int cturn = 0;

    const int newdegree = added ? added->degree : degree;
    const int deg = newdegree ? newdegree : 1;

    // Beneficial enchantments (like Haste) should not be throttled by
    // monster HD via modded_speed(). Use mod_speed instead!
    switch (ench)
    {
    case ENCH_HASTE:
    case ENCH_SWIFT:
    case ENCH_MIGHT:
    case ENCH_INVIS:
        cturn = 1000 / _mod_speed(25, mons->speed);
        break;
    case ENCH_SLOW:
        cturn = 250 / (1 + modded_speed(mons, 10));
        break;
    case ENCH_FEAR:
        cturn = 150 / (1 + modded_speed(mons, 5));
        break;
    case ENCH_PARALYSIS:
        cturn = std::max(90 / modded_speed(mons, 5), 3);
        break;
    case ENCH_PETRIFIED:
        cturn = std::max(8, 150 / (1 + modded_speed(mons, 5)));
        break;
    case ENCH_PETRIFYING:
        cturn = 50 / _mod_speed(10, mons->speed);
        break;
    case ENCH_CONFUSION:
        cturn = std::max(100 / modded_speed(mons, 5), 3);
        break;
    case ENCH_HELD:
        cturn = 120 / _mod_speed(25, mons->speed);
        break;
    case ENCH_POISON:
        cturn = 1000 * deg / _mod_speed(125, mons->speed);
        break;
    case ENCH_STICKY_FLAME:
        cturn = 1000 * deg / _mod_speed(200, mons->speed);
        break;
    case ENCH_ROT:
        if (deg > 1)
            cturn = 1000 * (deg - 1) / _mod_speed(333, mons->speed);
        cturn += 1000 / _mod_speed(250, mons->speed);
        break;
    case ENCH_CORONA:
        if (deg > 1)
            cturn = 1000 * (deg - 1) / _mod_speed(200, mons->speed);
        cturn += 1000 / _mod_speed(100, mons->speed);
        break;
    case ENCH_SHORT_LIVED:
        cturn = 1000 / _mod_speed(200, mons->speed);
        break;
    case ENCH_SLOWLY_DYING:
        // This may be a little too direct but the randomization at the end
        // of this function is excessive for toadstools. -cao
        return (2 * FRESHEST_CORPSE + random2(10))
                  * speed_to_duration(mons->speed) * mons->speed / 10;
    case ENCH_SPORE_PRODUCTION:
        // This is used as a simple timer, when the enchantment runs out
        // the monster will create a giant spore.
        return (random_range(475, 525) * 10);

    case ENCH_ABJ:
        if (deg >= 6)
            cturn = 1000 / _mod_speed(10, mons->speed);
        if (deg >= 5)
            cturn += 1000 / _mod_speed(20, mons->speed);
        cturn += 1000 * std::min(4, deg) / _mod_speed(100, mons->speed);
        break;
    case ENCH_CHARM:
        cturn = 500 / modded_speed(mons, 10);
        break;
    case ENCH_TP:
        cturn = 1000 * deg / _mod_speed(1000, mons->speed);
        break;
    case ENCH_SLEEP_WARY:
        cturn = 1000 / _mod_speed(50, mons->speed);
        break;
    default:
        break;
    }

    cturn = std::max(2, cturn);

    int raw_duration = (cturn * speed_to_duration(mons->speed));
    raw_duration = std::max(15, fuzz_value(raw_duration, 60, 40));

    return (raw_duration);
}

// Calculate the effective duration (in terms of normal player time - 10
// duration units being one normal player action) of this enchantment.
void mon_enchant::set_duration(const monsters *mons, const mon_enchant *added)
{
    if (duration && !added)
        return;

    if (added && added->duration)
        duration += added->duration;
    else
        duration += calc_duration(mons, added);

    if (duration > maxduration)
        maxduration = duration;
}