/*
 *  File:       it_use3.cc
 *  Summary:    Functions for using some of the wackier inventory items.
 *  Written by: Linley Henzell
 *
 *  Modified for Crawl Reference by $Author$ on $Date$
 *
 *  Change History (most recent first):
 *
 *      <4>     6/13/99         BWR             Auto ID Channel staff
 *      <3>     5/22/99         BWR             SPWLD_POWER is now HP/13 - 3
 *      <2>     5/20/99         BWR             Capped SPWLD_POWER to +20
 *      <1>     -/--/--         LRH             Created
 */

#include "AppHdr.h"
#include "it_use3.h"

#include <cstdlib>
#include <string.h>

#include "externs.h"

#include "beam.h"
#include "cloud.h"
#include "decks.h"
#include "direct.h"
#include "effects.h"
#include "fight.h"
#include "food.h"
#include "invent.h"
#include "items.h"
#include "it_use2.h"
#include "itemname.h"
#include "itemprop.h"
#include "mapmark.h"
#include "misc.h"
#include "monplace.h"
#include "monstuff.h"
#include "overmap.h"
#include "player.h"
#include "randart.h"
#include "religion.h"
#include "skills.h"
#include "skills2.h"
#include "spells1.h"
#include "spells2.h"
#include "spl-book.h"
#include "spl-cast.h"
#include "spl-util.h"
#include "stuff.h"
#include "view.h"

static bool ball_of_energy(void);
static bool ball_of_fixation(void);
static bool ball_of_seeing(void);
static bool box_of_beasts(void);
static bool disc_of_storms(void);
static bool efreet_flask(void);

void special_wielded()
{
    const int wpn = you.equip[EQ_WEAPON];
    const int old_plus = you.inv[wpn].plus;
    const int old_plus2 = you.inv[wpn].plus2;
    const char old_colour = you.inv[wpn].colour;
    bool makes_noise = false;

    switch (you.special_wield)
    {
    case SPWLD_SING:
    case SPWLD_NOISE:
    {
        makes_noise = (one_chance_in(20) && !silenced(you.x_pos, you.y_pos));
          
        if (makes_noise)
        {
            // Singing Sword only: singing and other musical noises
            const char* suffixes_sing[] = {
                 "hums a little tune.", "breaks into glorious song!",
                 "sings.", "sings loudly.", "chimes melodiously.",
                 "sings off-key.", "sings 'tra-la-la'.", "sings a lullaby.",
                 "chimes harmoniously.", "makes beautiful music.",
                 "produces a loud orchestral chord.", "whines plaintively.",
                 "tinkles.", "rings like a bell.", "wails mournfully.",
                 "practices its scales.", "lilts tunefully.", "yodels.",
                 "hums tunelessly.", "makes a painfully high-pitched squeak.",
                 "sings a sudden staccato note.", "sings a catchy tune.",
                 "says 'Hi! I'm the Singing Sword!'", "hums a slow waltz.",
                 "imitates a saxophone.", "shouts 'Sing with me!'",
                 "chimes like a gong.", "applauds itself.", "whistles merrily.",
                 "goes 'Da-da-da-dum.", "goes toot-toot!", "chants serenely.",
                 "trills happily.", "shouts 'One, two, three...'",
                 "chants a little melody.", "sings a deeply moving song.",
                 "hums an eerie melody.", "hums a slow and mournful tune.",
                 "launches into yet another solo.", "strikes up a merry tune.",
                 "emits a series of high-pitched trills.", "does a drum roll.",
                 "holds a dissonant chord.", "composes a new song.",
                 "makes a sound as if to clear its throat.", "beats time.",
                 "sings a quivering drawn-out note.", "sings a little jingle.",
                 "makes a twanging sound.", "spouts musical wisdom."
            };

            // mostly chatter and other human-like sounds
            const char* suffixes_talk[] = {
                 "speaks gibberish.", "raves incoherently.", "shouts 'Help!'",
                 "growls menacingly.", "sputters and hisses.", "hollers!",
                 "pants and wheezes.", "barks abruptly.", "sighs.", "wails.",
                 "howls with laughter!", "laughs crazily.", "burps!",
                 "goes snicker-snack!", "lets out a mournful sigh.",
                 "yells in some weird language.", "makes a horrible noise.",
                 "makes a deep moaning sound.", "gives off a wolf whistle.",
                 "wails.", "giggles.", "lets out a whoop!", "yawns loudly.",
                 "chatters happily.", "recites a poem.", "prattles on and on.",
                 "regales you with its life story.", "intones a prayer.",
                 "shouts 'Whoopee!'", "hurls insults at you.", "cries out!",
                 "argues with itself.", "complains about the scenery.",
                 "says 'I'm bored.'", "calls out a warning!", "swears loudly.",
                 "inquires about your family.", "coughs loudly.",
                 "burbles away merrily.", "gurgles.", "suddenly shrieks!",
                 "cackles.", "warbles.", "suddenly bursts into laughter!",
                 "shouts out instructions!", "cheers you on.", "snorts.",
                 "comments on the weather.", "makes a deep, guttural noise.",
                 "gives off a sizzling sound.", "whistles innocently.",
                 "makes a popping sound.", "says 'Ssh! Did you hear that?'",
                 "yelps loudly!", "lets out a series of bird calls."
            };

            // noises in the form "Your hear ...", mostly in-game noises
            const char* suffixes_sounds[] = {
                "a voice call your name.", "a shout.", "an angry hiss.",
                "a very strange noise.", "a high-pitched scream!",
                "a roar!", "someone snoring.", "a hideous shriek!",
                "a piteous moan.", "a screech!", "a bellow!",
                "a loud, deep croak!", "an angry buzzing noise.", 
                "an irritating high-pitched whine.", "a splashing noise.",
                "the sound of rushing water.", "a sizzling sound.",
                "someone calling for help!", "strange voices.", 
                "a loud clanging noise!", "a grinding noise.", "a knock.",
                "a mighty clap of thunder!", "maniacal laughter.",
                "a hideous screaming!", "snatches of song.", "a bark!",
                "a rumbling sound.", "a twanging sound.", "an echo. Echo.",
                "the chiming of a distant gong.", "a crunching sound.",
                "the tinkle of an enormous bell.", "a distant \"Zot\"!",
                "the distant roaring of an enraged frog.", "an echo.",
                "the wailing of sirens.", "a flourish of trumpets!"
            };

            int num_suffixes;
            std::string message;
            msg_channel_type channel = MSGCH_TALK;
            
            if (you.special_wield == SPWLD_SING)
            {
                message = "The Singing Sword ";
                if (!one_chance_in(5)) // sings
                {
                    num_suffixes = sizeof(suffixes_sing)
                                   / sizeof(suffixes_sing[0]);
                    message += suffixes_sing[random2(num_suffixes)];
                }
                else // talks
                {
                    num_suffixes = sizeof(suffixes_talk)
                                   / sizeof(suffixes_talk[0]);
                    message += suffixes_talk[random2(num_suffixes)];
                }
            }
            else // SPWLD_NOISE
            {
                if (one_chance_in(3)) // "You hear..." noises
                {
                    message = "You hear ";
                    num_suffixes = sizeof(suffixes_sounds)
                                   / sizeof(suffixes_sounds[0]);
                    message += suffixes_sounds[random2(num_suffixes)];
                    channel = MSGCH_SOUND;
                }
                else // normal chatter
                {
                    message = "Your ";
                    message += you.inv[wpn].name(DESC_BASENAME);
                    message += " ";
                    num_suffixes = sizeof(suffixes_talk)
                                   / sizeof(suffixes_talk[0]);
                    message += suffixes_talk[random2(num_suffixes)];
                }
            }
            mpr(message.c_str(), channel);

        } // makes_noise
        break;
    } 
    
    case SPWLD_CURSE:
        if (one_chance_in(30))
            curse_an_item(false);
        break;

    case SPWLD_VARIABLE:
        do_uncurse_item( you.inv[wpn] );

        if (random2(5) < 2)     // 40% chance {dlb}
            you.inv[wpn].plus  += (coinflip() ? +1 : -1);

        if (random2(5) < 2)     // 40% chance {dlb}
            you.inv[wpn].plus2 += (coinflip() ? +1 : -1);

        if (you.inv[wpn].plus < -4)
            you.inv[wpn].plus = -4;
        else if (you.inv[wpn].plus > 16)
            you.inv[wpn].plus = 16;

        if (you.inv[wpn].plus2 < -4)
            you.inv[wpn].plus2 = -4;
        else if (you.inv[wpn].plus2 > 16)
            you.inv[wpn].plus2 = 16;

        you.inv[wpn].colour = random_colour();
        break;

    case SPWLD_TORMENT:
        if (one_chance_in(200))
        {
            torment( TORMENT_SPWLD, you.x_pos, you.y_pos );
            did_god_conduct( DID_UNHOLY, 1 );
        }
        break;

    case SPWLD_ZONGULDROK:
        if (one_chance_in(5))
        {
            animate_dead( 1 + random2(3), BEH_HOSTILE, MHITYOU, 1 );
            did_god_conduct( DID_NECROMANCY, 1 );
        }
        break;

    case SPWLD_POWER:
        you.inv[wpn].plus = stepdown_value( -4 + (you.hp / 5), 4, 4, 4, 20 );
        you.inv[wpn].plus2 = you.inv[wpn].plus;
        break;

    case SPWLD_OLGREB:
        // Giving Olgreb's staff a little lift since staves of poison have
        // been made better. -- bwr
        you.inv[wpn].plus = you.skills[SK_POISON_MAGIC] / 3;
        you.inv[wpn].plus2 = you.inv[wpn].plus;
        break;

    case SPWLD_WUCAD_MU:
        you.inv[wpn].plus  = ((you.intel > 25) ? 22 : you.intel - 3);
        you.inv[wpn].plus2 = ((you.intel > 25) ? 13 : you.intel / 2);
        break;

    case SPWLD_SHADOW:
        if (random2(8) <= player_spec_death())
        {
            did_god_conduct( DID_NECROMANCY, 1 );
            create_monster( MONS_SHADOW, 2, BEH_FRIENDLY,
                            you.x_pos, you.y_pos, you.pet_target, 250 );
        }

        show_green = DARKGREY;
        break;

    //case SPWLD_PRUNE:
    default:
        return;
    }

    if (makes_noise)
        noisy( 25, you.x_pos, you.y_pos );

    if (old_plus != you.inv[wpn].plus
        || old_plus2 != you.inv[wpn].plus2
        || old_colour != you.inv[wpn].colour)
    {
        you.wield_change = true;
    }

    return;
}                               // end special_wielded()

static void reaching_weapon_attack(void)
{
    struct dist beam;
    int x_distance, y_distance;
    int x_middle, y_middle;
    int skill;

    mpr("Attack whom?", MSGCH_PROMPT);

    direction(beam, DIR_TARGET, TARG_ENEMY);
    if (!beam.isValid)
        return;

    if (beam.isMe)
    {
        canned_msg(MSG_UNTHINKING_ACT);
        return;
    }

    x_distance = abs(beam.tx - you.x_pos);
    y_distance = abs(beam.ty - you.y_pos);

    if (x_distance > 2 || y_distance > 2)
        mpr("Your weapon cannot reach that far!");
    else if (mgrd[beam.tx][beam.ty] == NON_MONSTER)
    {
        mpr("You attack empty space.");
    }
    else
    {
        /* BCR - Added a check for monsters in the way.  Only checks cardinal
         *       directions.  Knight moves are ignored.  Assume the weapon
         *       slips between the squares.
         */

        // if we're attacking more than a space away
        if ((x_distance > 1) || (y_distance > 1))
        {
            x_middle = MAX(beam.tx, you.x_pos) - (x_distance / 2);
            y_middle = MAX(beam.ty, you.y_pos) - (y_distance / 2);

            // if either the x or the y is the same, we should check for
            // a monster:
            if (((beam.tx == you.x_pos) || (beam.ty == you.y_pos))
                    && (mgrd[x_middle][y_middle] != NON_MONSTER))
            {
                skill = weapon_skill( you.inv[you.equip[EQ_WEAPON]].base_type,
                                      you.inv[you.equip[EQ_WEAPON]].sub_type );

                if ((5 + (3 * skill)) > random2(100))
                {
                    mpr("You reach to attack!");
                    you_attack(mgrd[beam.tx][beam.ty], false);
                }
                else
                {
                    mpr("You could not reach far enough!");
                    you_attack(mgrd[x_middle][y_middle], false);
                }
            }
            else
            {
                mpr("You reach to attack!");
                you_attack(mgrd[beam.tx][beam.ty], false);
            }
        }
        else
        {
            you_attack(mgrd[beam.tx][beam.ty], false);
        }
    }

    return;
}                               // end reaching_weapon_attack()

// returns true if item successfully evoked.
bool evoke_wielded( void )
{
    char opened_gates = 0;
    unsigned char spell_casted = random2(21);
    int count_x, count_y;
    int temp_rand = 0;      // for probability determination {dlb}
    int power = 0;

    int pract = 0;
    bool did_work = false;  // used for default "nothing happens" message

    int wield = you.equip[EQ_WEAPON];

    if (you.duration[DUR_BERSERKER])
    {
        canned_msg( MSG_TOO_BERSERK );
        return (false);
    }
    else if (wield == -1)
    {
        mpr("You aren't wielding anything!");
        return (false);
    }

    item_def& wpn = you.inv[wield];
    bool unevokable = false;

    // Check inscriptions.
    if ( !check_warning_inscriptions(wpn, OPER_EVOKE) )
        return false;

    switch (wpn.base_type)
    {
    case OBJ_WEAPONS:
        if (get_weapon_brand( wpn ) == SPWPN_REACHING
            && enough_mp(1, false))
        {
            // needed a cost to prevent evocation training abuse -- bwr
            dec_mp(1);
            make_hungry( 50, false );  
            reaching_weapon_attack();
            pract = (one_chance_in(5) ? 1 : 0);
            did_work = true;
        }
        else if (is_fixed_artefact( wpn ))
        {
            switch (wpn.special)
            {
            case SPWPN_STAFF_OF_DISPATER:
                if (you.duration[DUR_DEATHS_DOOR] || !enough_hp(11, true) 
                    || !enough_mp(5, true))
                {
                    break;
                }

                mpr("You feel the staff feeding on your energy!");

                dec_hp( 5 + random2avg(19, 2), false, "Staff of Dispater" );
                dec_mp( 2 + random2avg(5, 2) );
                make_hungry( 100, false );

                power = you.skills[SK_EVOCATIONS] * 8;
                your_spells( SPELL_HELLFIRE, power, false );
                pract = (coinflip() ? 2 : 1);
                did_work = true;
                break;

            // let me count the number of ways spell_casted is
            // used here ... one .. two .. three ... >CRUNCH<
            // three licks to get to the center of a ... {dlb}
            case SPWPN_SCEPTRE_OF_ASMODEUS:
                spell_casted = random2(21);

                if (spell_casted == 0)
                    break;

                make_hungry( 200, false );
                pract = 1;

                if (spell_casted < 2)   // summon devils, maybe a Fiend
                {

                    spell_casted = (one_chance_in(4) ? MONS_FIEND
                                                 : MONS_HELLION + random2(10));

                    bool good_summon = (create_monster( spell_casted, 
                                            6, BEH_HOSTILE,
                                            you.x_pos, you.y_pos, 
                                            MHITYOU, 250) != -1);

                    if (good_summon)
                    {
                        if (spell_casted == MONS_FIEND)
                            mpr("\"Your arrogance condemns you, mortal!\"");
                        else
                            mpr("The Sceptre summons one of its servants.");
                    }

                    did_work = true;
                    break;
                }

                temp_rand = random2(240);

                if (temp_rand > 125)
                    spell_casted = SPELL_BOLT_OF_FIRE;      // 114 in 240
                else if (temp_rand > 68)
                    spell_casted = SPELL_LIGHTNING_BOLT;    //  57 in 240
                else if (temp_rand > 11)
                    spell_casted = SPELL_BOLT_OF_DRAINING;  //  57 in 240
                else
                    spell_casted = SPELL_HELLFIRE;          //  12 in 240

                power = you.skills[SK_EVOCATIONS] * 8;
                your_spells( static_cast<spell_type>(spell_casted),
                             power, false );
                did_work = true;
                break;

            case SPWPN_STAFF_OF_OLGREB:
                if (!enough_mp( 4, true ) 
                    || you.skills[SK_EVOCATIONS] < random2(6))
                {
                    break;
                }

                dec_mp(4);
                make_hungry( 50, false );
                pract = 1;
                did_work = true;

                power = 10 + you.skills[SK_EVOCATIONS] * 8;

                your_spells( SPELL_OLGREBS_TOXIC_RADIANCE, power, false );

                if (you.skills[SK_EVOCATIONS] >= random2(10))
                    your_spells( SPELL_VENOM_BOLT, power, false );
                break;

            case SPWPN_STAFF_OF_WUCAD_MU:
                if (you.magic_points == you.max_magic_points
                    || you.skills[SK_EVOCATIONS] < random2(25))
                {
                    break;
                }

                mpr("Magical energy flows into your mind!");

                inc_mp( 3 + random2(5) + you.skills[SK_EVOCATIONS] / 3, false );
                make_hungry( 50, false );
                pract = 1;
                did_work = true;

                if (one_chance_in(3))
                {
                    miscast_effect( SPTYP_DIVINATION, random2(9), 
                                    random2(70), 100, "the Staff of Wucad Mu" );
                }
                break;

            default:
                unevokable = true;
                break;
            }
        }
        else
        {
            unevokable = true;
        }
        break;

    case OBJ_STAVES:
        if (item_is_rod( wpn ))
        {
            pract = staff_spell( wield );
            // [ds] Early exit, no turns are lost.
            if (pract == -1)
                return (false);

            did_work = true;  // staff_spell() will handle messages
        }
        else if (wpn.sub_type == STAFF_CHANNELING)
        {
            if (you.magic_points < you.max_magic_points 
                && you.skills[SK_EVOCATIONS] >= random2(30)) 
            {
                mpr("You channel some magical energy.");
                inc_mp( 1 + random2(3), false );
                make_hungry( 50, false );
                pract = (one_chance_in(5) ? 1 : 0);
                did_work = true;

                if (!item_type_known(wpn))
                {
                    set_ident_flags( wpn, ISFLAG_KNOW_TYPE );

                    mprf("You are wielding %s.",
                         wpn.name(DESC_NOCAP_A).c_str());
                         
                    more();

                    you.wield_change = true;
                }
            }
        }
        else
        {
            unevokable = true;
        }
        break;

    case OBJ_MISCELLANY:
        did_work = true; // easier to do it this way for misc items
        
        if ( is_deck(wpn) )
        {
            evoke_deck(wpn);
            pract = 1;
            break;
        }

        switch (wpn.sub_type)
        {
        case MISC_BOTTLED_EFREET:
            if (efreet_flask())
                pract = 2;
            break;

        case MISC_CRYSTAL_BALL_OF_SEEING:
            if (ball_of_seeing())
                pract = 1;
            break;

        case MISC_AIR_ELEMENTAL_FAN:
            if (you.skills[SK_EVOCATIONS] <= random2(30))
                canned_msg(MSG_NOTHING_HAPPENS);
            else
            {
                summon_elemental(100, MONS_AIR_ELEMENTAL, 4);
                pract = (one_chance_in(5) ? 1 : 0);
            }
            break;

        case MISC_LAMP_OF_FIRE:
            if (you.skills[SK_EVOCATIONS] <= random2(30))
                canned_msg(MSG_NOTHING_HAPPENS);
            else
            {
                summon_elemental(100, MONS_FIRE_ELEMENTAL, 4);
                pract = (one_chance_in(5) ? 1 : 0);
            }
            break;

        case MISC_STONE_OF_EARTH_ELEMENTALS:
            if (you.skills[SK_EVOCATIONS] <= random2(30))
                canned_msg(MSG_NOTHING_HAPPENS);
            else
            {
                summon_elemental(100, MONS_EARTH_ELEMENTAL, 4);
                pract = (one_chance_in(5) ? 1 : 0);
            }
            break;

        case MISC_HORN_OF_GERYON:
            // Note: This assumes that the Vestibule has not been changed.
            if (player_in_branch( BRANCH_VESTIBULE_OF_HELL ))
            {
                mpr("You produce a weird and mournful sound.");

                for (count_x = 0; count_x < GXM; count_x++)
                {
                    for (count_y = 0; count_y < GYM; count_y++)
                    {
                        if (grd[count_x][count_y] == DNGN_STONE_ARCH)
                        {
                            opened_gates++;

                            map_marker *marker =
                                env.markers.find(coord_def(count_x, count_y),
                                                 MAT_FEATURE);

                            if (marker)
                            {
                                map_feature_marker *featm =
                                    dynamic_cast<map_feature_marker*>(marker);
                                grd[count_x][count_y] = featm->feat;
                                env.markers.remove(marker);
                            }
                        }
                    }
                }

                if (opened_gates)
                {
                    mpr("Your way has been unbarred.");
                    pract = 1;
                }
            }
            else
            {
                mpr("You produce a hideous howling noise!");
                int midx = create_monster( MONS_BEAST, 4,
                                           BEH_HOSTILE, you.x_pos, you.y_pos,
                                           MHITYOU, 250 );
                // avoid scumming; also prevents it from showing up on notes
                if ( midx != -1 )
                    menv[midx].flags |= MF_CREATED_FRIENDLY;
                // no practice
            }
            break;

        case MISC_BOX_OF_BEASTS:
            if (box_of_beasts())
                pract = 1;
            break;

        case MISC_CRYSTAL_BALL_OF_ENERGY:
            if (ball_of_energy())
                pract = 1;
            break;

        case MISC_CRYSTAL_BALL_OF_FIXATION:
            if (ball_of_fixation())
                pract = 1;
            break;

        case MISC_DISC_OF_STORMS:
            if (disc_of_storms())
                pract = (coinflip() ? 2 : 1);
            break;

        default:
            did_work = false;
            unevokable = true;
            break;
        }
        break;

    default:
        unevokable = true;
        break;
    }

    if (!did_work)
        canned_msg(MSG_NOTHING_HAPPENS);
    else if (pract > 0)
        exercise( SK_EVOCATIONS, pract );

    if (!unevokable)
        you.turn_is_over = true;

    return (did_work);
}                               // end evoke_wielded()

static bool efreet_flask(void)
{
    const beh_type behaviour = ((you.skills[SK_EVOCATIONS] > random2(20)) 
                                ? BEH_FRIENDLY : BEH_HOSTILE);

    mpr("You open the flask...");

    const int efreet = create_monster( MONS_EFREET, 5, behaviour, 
                                       you.x_pos, you.y_pos, MHITYOU, 250,
                                       false, false, true );
    if (efreet != -1)
    {
        monsters *mon = &menv[efreet];
        
        mpr( "...and a huge efreet comes out." );
        player_angers_monster(mon);
        mpr( (mon->attitude == ATT_FRIENDLY)?
             "\"Thank you for releasing me!\""
             : "It howls insanely!" );
    }
    else
        canned_msg(MSG_NOTHING_HAPPENS);

    dec_inv_item_quantity( you.equip[EQ_WEAPON], 1 );    

    return (true);
}                               // end efreet_flask()

static bool ball_of_seeing(void)
{
    int use = 0;
    bool ret = false;

    mpr("You gaze into the crystal ball.");

    use = ((!you.duration[DUR_CONF]) ? random2(you.skills[SK_EVOCATIONS] * 6) : random2(5));

    if (use < 2)
    {
        lose_stat( STAT_INTELLIGENCE, 1 );
    }
    else if (use < 5 && enough_mp(1, true))
    {
        mpr("You feel power drain from you!");
        set_mp(0, false);
    }
    else if (use < 10)
    {
        confuse_player( 10 + random2(10), false );
    }
    else if (use < 15 || coinflip())
    {
        mpr("You see nothing.");
    }
    else if (magic_mapping( 15, 50 + random2( you.skills[SK_EVOCATIONS]), true))
    {
        mpr("You see a map of your surroundings!");
        ret = true;
    }
    else
    {
        mpr("You see nothing.");
    }

    return (ret);
}                               // end ball_of_seeing()

static bool disc_of_storms(void)
{
    int temp_rand = 0;          // probability determination {dlb}
    int disc_count = 0;

    const int fail_rate = (30 - you.skills[SK_EVOCATIONS]);
    bool ret = false;

    if (player_res_electricity() || (random2(100) < fail_rate))
        canned_msg(MSG_NOTHING_HAPPENS);
    else if (random2(100) < fail_rate)
        mpr("The disc glows for a moment, then fades.");
    else if (random2(100) < fail_rate)
        mpr("Little bolts of electricity crackle over the disc.");
    else
    {
        mpr("The disc erupts in an explosion of electricity!");

        disc_count = roll_dice( 2, 1 + you.skills[SK_EVOCATIONS] / 7 );

        while (disc_count)
        {
            bolt beam;

            temp_rand = random2(3);

            zap_type which_zap = ((temp_rand > 1) ? ZAP_LIGHTNING :
                                  (temp_rand > 0) ? ZAP_ELECTRICITY
                                                  : ZAP_ORB_OF_ELECTRICITY);

            beam.source_x = you.x_pos;
            beam.source_y = you.y_pos;
            beam.target_x = you.x_pos + random2(13) - 6;
            beam.target_y = you.y_pos + random2(13) - 6;

            zapping( which_zap, 30 + you.skills[SK_EVOCATIONS] * 2, beam );

            disc_count--;
        }

        ret = true;
    }

    return (ret);
}                               // end disc_of_storms()

void tome_of_power(char sc_read_2)
{
    int temp_rand = 0;          // probability determination {dlb}

    int powc = 5 + you.skills[SK_EVOCATIONS] 
                 + roll_dice( 5, you.skills[SK_EVOCATIONS] ); 

    spell_type spell_casted = SPELL_NO_SPELL;
    struct bolt beam;

    msg::stream << "The book opens to a page covered in "
                << weird_writing() << '.' << std::endl;

    you.turn_is_over = true;

    if (!yesno("Read it?"))
        return;

    set_ident_flags( you.inv[sc_read_2], ISFLAG_IDENT_MASK );

    if (you.mutation[MUT_BLURRY_VISION] > 0
        && random2(4) < you.mutation[MUT_BLURRY_VISION])
    {
        mpr("The page is too blurry for you to read.");
        return;
    }

    mpr("You find yourself reciting the magical words!");
    exercise( SK_EVOCATIONS, 1 ); 

    temp_rand = random2(50) + random2( you.skills[SK_EVOCATIONS] / 3 ); 

    switch (random2(50))
    {
    case 0:
    case 3:
    case 4:
    case 6:
    case 7:
    case 8:
    case 9:
        mpr("A cloud of weird smoke pours from the book's pages!");
        big_cloud( random_smoke_type(), KC_YOU,
                   you.x_pos, you.y_pos, 20, 10 + random2(8) );
        xom_is_stimulated(16);
        return;
    case 1:
    case 14:
        mpr("A cloud of choking fumes pours from the book's pages!");
        big_cloud(CLOUD_POISON, KC_YOU,
                  you.x_pos, you.y_pos, 20, 7 + random2(5));
        xom_is_stimulated(64);
        return;

    case 2:
    case 13:
        mpr("A cloud of freezing gas pours from the book's pages!");
        big_cloud(CLOUD_COLD, KC_YOU, you.x_pos, you.y_pos, 20, 8 + random2(5));
        xom_is_stimulated(64);
        return;

    case 5:
    case 11:
    case 12:
        if (one_chance_in(5))
        {
            mpr("The book disappears in a mighty explosion!");
            dec_inv_item_quantity( sc_read_2, 1 );
        }

        beam.type = SYM_BURST;
        beam.damage = dice_def( 3, 15 );
        // unsure about this    // BEAM_EXPLOSION instead? [dlb]
        beam.flavour = BEAM_FIRE;
        beam.target_x = you.x_pos;
        beam.target_y = you.y_pos;
        beam.name = "fiery explosion";
        beam.colour = RED;
        // your explosion, (not someone else's explosion)
        beam.beam_source = NON_MONSTER;
        beam.thrower = KILL_YOU;
        beam.aux_source = "an exploding Tome of Power";
        beam.ex_size = 2;
        beam.is_tracer = false;
        beam.is_explosion = true;

        explosion(beam);
        xom_is_stimulated(255);
        return;

    case 10:
        if (create_monster( MONS_ABOMINATION_SMALL, 6, BEH_HOSTILE,
                            you.x_pos, you.y_pos, MHITYOU, 250 ) != -1)
        {
            mpr("A horrible Thing appears!");
            mpr("It doesn't look too friendly.");
        }
        xom_is_stimulated(255);
        return;
    }

    viewwindow(1, false);

    temp_rand = random2(23) + random2( you.skills[SK_EVOCATIONS] / 3 );

    if (temp_rand > 25)
        temp_rand = 25;

    spell_casted = ((temp_rand > 19) ? SPELL_FIREBALL :
                    (temp_rand > 16) ? SPELL_BOLT_OF_FIRE :
                    (temp_rand > 13) ? SPELL_BOLT_OF_COLD :
                    (temp_rand > 11) ? SPELL_LIGHTNING_BOLT :
                    (temp_rand > 10) ? SPELL_LEHUDIBS_CRYSTAL_SPEAR :
                    (temp_rand >  9) ? SPELL_VENOM_BOLT :
                    (temp_rand >  8) ? SPELL_BOLT_OF_DRAINING :
                    (temp_rand >  7) ? SPELL_BOLT_OF_INACCURACY :
                    (temp_rand >  6) ? SPELL_STICKY_FLAME :
                    (temp_rand >  5) ? SPELL_TELEPORT_SELF :
                    (temp_rand >  4) ? SPELL_CIGOTUVIS_DEGENERATION :
                    (temp_rand >  3) ? SPELL_POLYMORPH_OTHER :
                    (temp_rand >  2) ? SPELL_MEPHITIC_CLOUD :
                    (temp_rand >  1) ? SPELL_THROW_FLAME :
                    (temp_rand >  0) ? SPELL_THROW_FROST
                                     : SPELL_MAGIC_DART);

    your_spells( spell_casted, powc, false );
}                               // end tome_of_power()

void skill_manual(char sc_read_2)
{
    set_ident_flags( you.inv[sc_read_2], ISFLAG_IDENT_MASK );

    const int skill = you.inv[sc_read_2].plus;

    const char* skname = skill_name(skill);
    mprf("This is a manual of %s!", skname);

    you.turn_is_over = true;

    if (!yesno("Read it?"))
        return;

    mprf("You read about %s.", skname);

    exercise(skill, 500);

    if (one_chance_in(10))
    {
        mpr("The book crumbles into dust.");
        dec_inv_item_quantity( sc_read_2, 1 );
    }
    else
    {
        mpr("The book looks somewhat more worn.");
    }
    xom_is_stimulated(14);
}                               // end skill_manual()

static bool box_of_beasts()
{
    int beasty = MONS_PROGRAM_BUG;      // error trapping {dlb}
    int temp_rand = 0;          // probability determination {dlb}

    int ret = false;

    mpr("You open the lid...");

    if (random2(100) < 60 + you.skills[SK_EVOCATIONS])
    {
        temp_rand = random2(11);

        beasty = ((temp_rand == 0) ? MONS_GIANT_BAT :
                  (temp_rand == 1) ? MONS_HOUND :
                  (temp_rand == 2) ? MONS_JACKAL :
                  (temp_rand == 3) ? MONS_RAT :
                  (temp_rand == 4) ? MONS_ICE_BEAST :
                  (temp_rand == 5) ? MONS_SNAKE :
                  (temp_rand == 6) ? MONS_YAK :
                  (temp_rand == 7) ? MONS_BUTTERFLY :
                  (temp_rand == 8) ? MONS_HELL_HOUND :
                  (temp_rand == 9) ? MONS_BROWN_SNAKE 
                                   : MONS_GIANT_LIZARD);

        beh_type beh = (one_chance_in(you.skills[SK_EVOCATIONS] + 5)
                        ? BEH_HOSTILE : BEH_FRIENDLY);

        if (create_monster( beasty, 2 + random2(4), beh,
                            you.x_pos, you.y_pos, MHITYOU, 250 ) != -1)
        {
            mpr("...and something leaps out!");
            xom_is_stimulated(14);
            ret = true;
        }
    }
    else
    {
        if (!one_chance_in(6))
            mpr("...but nothing happens.");
        else
        {
            mpr("...but the box appears empty.");
            you.inv[you.equip[EQ_WEAPON]].sub_type = MISC_EMPTY_EBONY_CASKET;
        }
    }

    return (ret);
}                               // end box_of_beasts()

static bool ball_of_energy(void)
{
    int use = 0;
    int proportional = 0;

    bool ret = false;

    mpr("You gaze into the crystal ball.");

    use = ((!you.duration[DUR_CONF]) ? random2(you.skills[SK_EVOCATIONS] * 6) : random2(6));

    if (use < 2 || you.max_magic_points == 0)
    {
        lose_stat(STAT_INTELLIGENCE, 1);
    }
    else if ((use < 4 && enough_mp(1, true))
             || you.magic_points == you.max_magic_points)
    {
        mpr( "You feel your power drain away!" );
        set_mp( 0, false );
    }
    else if (use < 6)
    {
        confuse_player( 10 + random2(10), false );
    }
    else
    {
        proportional = you.magic_points * 100;
        proportional /= you.max_magic_points;

        if (random2avg(77 - you.skills[SK_EVOCATIONS] * 2, 4) > proportional 
            || one_chance_in(25))
        {
            mpr( "You feel your power drain away!" );
            set_mp( 0, false );
        }
        else
        {
            mpr( "You are suffused with power!" );
            inc_mp( 6 + roll_dice( 2, you.skills[SK_EVOCATIONS] ), false );

            ret = true;
        }
    }

    return (ret);
}                               // end ball_of_energy()

static bool ball_of_fixation(void)
{
    mpr("You gaze into the crystal ball.");
    mpr("You are mesmerised by a rainbow of scintillating colours!");

    you.duration[DUR_PARALYSIS] = 100;
    you.duration[DUR_SLOW] = 100;

    return (true);
}                               // end ball_of_fixation()