/*
 *  File:       goditem.cc
 *  Summary:    Gods' attitude towards items.
 */

#include "AppHdr.h"

#include "religion.h"
#include "goditem.h"

#include <algorithm>
#include <sstream>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <cmath>

#include "externs.h"

bool is_holy_item(const item_def& item)
{
    bool retval = false;

    if (is_unrandom_artefact(item))
    {
        unrandart_entry* entry = get_unrand_entry(item.special);

        if (entry->flags & UNRAND_FLAG_HOLY)
            return (true);
    }

    switch (item.base_type)
    {
    case OBJ_WEAPONS:
        retval = (is_blessed_blade(item)
                  || get_weapon_brand(item) == SPWPN_HOLY_WRATH);
        break;
    case OBJ_SCROLLS:
        retval = (item.sub_type == SCR_HOLY_WORD);
        break;
    case OBJ_BOOKS:
        retval = is_holy_spellbook(item);
        break;
    case OBJ_STAVES:
        retval = is_holy_rod(item);
        break;
    default:
        break;
    }

    return (retval);
}

bool is_potentially_evil_item(const item_def& item)
{
    switch (item.base_type)
    {
    case OBJ_WEAPONS:
        {
        const int item_brand = get_weapon_brand(item);
        if (item_brand == SPWPN_CHAOS)
            return (true);
        }
        break;
    case OBJ_MISSILES:
        {
        const int item_brand = get_ammo_brand(item);
        if (item_brand == SPMSL_CHAOS)
            return (true);
        }
        break;
    case OBJ_WANDS:
        if (item.sub_type == WAND_RANDOM_EFFECTS)
            return (true);
        break;
    default:
        break;
    }

    return (false);
}

bool is_evil_item(const item_def& item)
{
    bool retval = false;

    if (is_unrandom_artefact(item))
    {
        unrandart_entry* entry = get_unrand_entry(item.special);

        if (entry->flags & UNRAND_FLAG_EVIL)
            return (true);
    }

    switch (item.base_type)
    {
    case OBJ_WEAPONS:
        {
        const int item_brand = get_weapon_brand(item);
        retval = (is_demonic(item)
                  || item_brand == SPWPN_DRAINING
                  || item_brand == SPWPN_PAIN
                  || item_brand == SPWPN_VAMPIRICISM
                  || item_brand == SPWPN_REAPING);
        }
        break;
    case OBJ_MISSILES:
    {
        const int item_brand = get_ammo_brand(item);
        retval = (item_brand == SPMSL_REAPING);
        break;
    }
    case OBJ_WANDS:
        retval = (item.sub_type == WAND_DRAINING);
        break;
    case OBJ_SCROLLS:
        retval = (item.sub_type == SCR_SUMMONING
                  || item.sub_type == SCR_TORMENT);
        break;
    case OBJ_POTIONS:
        retval = is_blood_potion(item);
        break;
    case OBJ_BOOKS:
        retval = is_evil_spellbook(item);
        break;
    case OBJ_STAVES:
        retval = (item.sub_type == STAFF_DEATH || is_evil_rod(item));
        break;
    case OBJ_MISCELLANY:
        retval = (item.sub_type == MISC_BOTTLED_EFREET
                  || item.sub_type == MISC_LANTERN_OF_SHADOWS);
        break;
    default:
        break;
    }

    return (retval);
}

bool is_chaotic_item(const item_def& item)
{
    bool retval = false;

    if (is_unrandom_artefact(item))
    {
        unrandart_entry* entry = get_unrand_entry(item.special);

        if (entry->flags & UNRAND_FLAG_CHAOTIC)
            return (true);
    }

    switch (item.base_type)
    {
    case OBJ_WEAPONS:
        {
        const int item_brand = get_weapon_brand(item);
        retval = (item_brand == SPWPN_CHAOS);
        }
        break;
    case OBJ_MISSILES:
        {
        const int item_brand = get_ammo_brand(item);
        retval = (item_brand == SPMSL_CHAOS);
        }
        break;
    case OBJ_WANDS:
        retval = (item.sub_type == WAND_POLYMORPH_OTHER);
        break;
    case OBJ_POTIONS:
        retval = (item.sub_type == POT_MUTATION);
        break;
    case OBJ_BOOKS:
        retval = is_chaotic_spellbook(item);
        break;
    case OBJ_STAVES:
        retval = is_chaotic_rod(item);
        break;
    default:
        break;
    }

    if (is_artefact(item) && artefact_wpn_property(item, ARTP_MUTAGENIC))
        retval = true;

    return (retval);
}

bool is_hasty_item(const item_def& item)
{
    bool retval = false;

    switch (item.base_type)
    {
    case OBJ_WEAPONS:
        {
        const int item_brand = get_weapon_brand(item);
        retval = (item_brand == SPWPN_SPEED
                  || item.sub_type == WPN_QUICK_BLADE);
        }
        break;
    case OBJ_ARMOUR:
        {
        const int item_brand = get_armour_ego_type(item);
        retval = (item_brand == SPARM_RUNNING);
        }
        break;
    case OBJ_WANDS:
        retval = (item.sub_type == WAND_HASTING);
        break;
    case OBJ_POTIONS:
        retval = (item.sub_type == POT_SPEED
                  || item.sub_type == POT_BERSERK_RAGE);
        break;
    case OBJ_JEWELLERY:
        retval = (item.sub_type == AMU_RAGE
                  || item.sub_type == AMU_RESIST_SLOW);
        break;
    default:
        break;
    }

    if (is_artefact(item)
        && artefact_wpn_property(item, ARTP_ANGRY)
            || artefact_wpn_property(item, ARTP_BERSERK))
    {
        retval = true;
    }

    return (retval);
}

bool is_holy_discipline(int discipline)
{
    return (discipline & SPTYP_HOLY);
}

bool is_evil_discipline(int discipline)
{
    return (discipline & SPTYP_NECROMANCY);
}

bool is_holy_spell(spell_type spell, god_type god)
{
    UNUSED(god);

    unsigned int disciplines = get_spell_disciplines(spell);

    return (is_holy_discipline(disciplines));
}

bool is_evil_spell(spell_type spell, god_type god)
{
    UNUSED(god);

    unsigned int flags       = get_spell_flags(spell);
    unsigned int disciplines = get_spell_disciplines(spell);

    return ((flags & SPFLAG_UNHOLY) || (is_evil_discipline(disciplines)));
}

bool is_chaotic_spell(spell_type spell, god_type god)
{
    UNUSED(god);

    return (spell == SPELL_POLYMORPH_OTHER
            || spell == SPELL_ALTER_SELF
            || spell == SPELL_SUMMON_UGLY_THING);
}

bool is_hasty_spell(spell_type spell, god_type god)
{
    UNUSED(god);

    return (spell == SPELL_HASTE
            || spell == SPELL_SWIFTNESS
            || spell == SPELL_BERSERKER_RAGE);
}

// The default suitable() function for is_spellbook_type().
bool is_any_spell(spell_type spell, god_type god)
{
    UNUSED(god);

    return (true);
}

// If book_or_rod is false, only look at actual spellbooks.  Otherwise,
// only look at rods.
bool is_spellbook_type(const item_def& item, bool book_or_rod,
                       bool (*suitable)(spell_type spell, god_type god),
                       god_type god)
{
    const bool is_spellbook = (item.base_type == OBJ_BOOKS
                                  && item.sub_type != BOOK_MANUAL
                                  && item.sub_type != BOOK_DESTRUCTION);
    const bool is_rod = item_is_rod(item);

    if (!is_spellbook && !is_rod)
        return (false);

    if (!book_or_rod && is_rod)
        return (false);

    int total       = 0;
    int total_liked = 0;

    for (int i = 0; i < SPELLBOOK_SIZE; ++i)
    {
        spell_type spell = which_spell_in_book(item, i);
        if (spell == SPELL_NO_SPELL)
            continue;

        total++;
        if (suitable(spell, god))
            total_liked++;
    }

    // If at least half of the available spells are suitable, the whole
    // spellbook or rod is, too.
    return (total_liked >= (total / 2) + 1);
}

bool is_holy_spellbook(const item_def& item)
{
    return (is_spellbook_type(item, false, is_holy_spell));
}

bool is_evil_spellbook(const item_def& item)
{
    return (is_spellbook_type(item, false, is_evil_spell));
}

bool is_chaotic_spellbook(const item_def& item)
{
    return (is_spellbook_type(item, false, is_chaotic_spell));
}

bool god_hates_spellbook(const item_def& item)
{
    return (is_spellbook_type(item, false, god_hates_spell_type));
}

bool is_holy_rod(const item_def& item)
{
    return (is_spellbook_type(item, true, is_holy_spell));
}

bool is_evil_rod(const item_def& item)
{
    return (is_spellbook_type(item, true, is_evil_spell));
}

bool is_chaotic_rod(const item_def& item)
{
    return (is_spellbook_type(item, true, is_chaotic_spell));
}

bool god_hates_rod(const item_def& item)
{
    return (is_spellbook_type(item, true, god_hates_spell_type));
}

conduct_type good_god_hates_item_handling(const item_def &item)
{
    if (!is_good_god(you.religion) || !is_evil_item(item))
        return (DID_NOTHING);

    if (is_demonic(item))
        return (DID_UNHOLY);

    if (item_type_known(item))
        return (DID_NECROMANCY);

    return (DID_NOTHING);
}

conduct_type god_hates_item_handling(const item_def &item)
{
    switch (you.religion)
    {
    case GOD_ZIN:
        if (item_type_known(item) && is_chaotic_item(item))
            return (DID_CHAOS);
        break;

    case GOD_SHINING_ONE:
    {
        if (!item_type_known(item))
            return (DID_NOTHING);

        switch (item.base_type)
        {
        case OBJ_WEAPONS:
        {
            const int item_brand = get_weapon_brand(item);
            if (item_brand == SPWPN_VENOM)
                return (DID_POISON);
            break;
        }

        case OBJ_MISSILES:
        {
            const int item_brand = get_ammo_brand(item);
            if (item_brand == SPMSL_POISONED || item_brand == SPMSL_CURARE)
                return (DID_POISON);
            break;
        }

        case OBJ_STAVES:
            if (item.sub_type == STAFF_POISON)
                return (DID_POISON);
            break;

        default:
            break;
        }
        break;
    }

    case GOD_YREDELEMNUL:
        if (item_type_known(item) && is_holy_item(item))
            return (DID_HOLY);
        break;

    case GOD_TROG:
        if (item.base_type == OBJ_BOOKS
            && item.sub_type != BOOK_MANUAL
            && item.sub_type != BOOK_DESTRUCTION)
        {
            return (DID_SPELL_MEMORISE);
        }
        break;

    case GOD_FEAWN:
        if (item_type_known(item)
            && is_potentially_evil_item(item) || is_evil_item(item))
        {
            return (DID_NECROMANCY);
        }
        break;

    case GOD_CHEIBRIADOS:
        if (item_type_known(item) && is_hasty_item(item))
            return (DID_HASTY);
        break;

    default:
        break;
    }

    if (item_type_known(item) && is_potentially_evil_item(item)
        && is_good_god(you.religion))
    {
        return (DID_NECROMANCY);
    }

    if (item_type_known(item)
        && (god_hates_spellbook(item) || god_hates_rod(item)))
    {
        return (NUM_CONDUCTS); // FIXME: get the specific reason, if it
    }                          // will ever be needed for spellbooks.

    return (DID_NOTHING);
}

bool god_hates_spell_type(spell_type spell, god_type god)
{
    if (is_good_god(god) && is_evil_spell(spell))
        return (true);

    unsigned int disciplines = get_spell_disciplines(spell);

    switch (god)
    {
    case GOD_ZIN:
        if (is_chaotic_spell(spell))
            return (true);
        break;

    case GOD_SHINING_ONE:
        // TSO hates using poison, but is fine with curing it, resisting
        // it, or destroying it.
        if ((disciplines & SPTYP_POISON) && spell != SPELL_CURE_POISON
            && spell != SPELL_RESIST_POISON && spell != SPELL_IGNITE_POISON)
        {
            return (true);
        }

    case GOD_YREDELEMNUL:
        if (is_holy_spell(spell))
            return (true);
        break;

    case GOD_CHEIBRIADOS:
        if (is_hasty_spell(spell))
            return (true);
        break;

    default:
        break;
    }

    return (false);
}

bool god_dislikes_spell_type(spell_type spell, god_type god)
{
    if (god_hates_spell_type(spell, god))
        return (true);

    unsigned int flags       = get_spell_flags(spell);
    unsigned int disciplines = get_spell_disciplines(spell);

    switch (god)
    {
    case GOD_SHINING_ONE:
        // TSO probably wouldn't like spells which would put enemies
        // into a state where attacking them would be unchivalrous.
        if (spell == SPELL_CAUSE_FEAR || spell == SPELL_PARALYSE
            || spell == SPELL_CONFUSE || spell == SPELL_MASS_CONFUSION
            || spell == SPELL_SLEEP   || spell == SPELL_MASS_SLEEP)
        {
            return (true);
        }
        break;

    case GOD_XOM:
        // Ideally, Xom would only like spells which have a random effect,
        // are risky to use, or would otherwise amuse him, but that would
        // be a really small number of spells.

        // Xom would probably find these extra boring.
        if (flags & (SPFLAG_HELPFUL | SPFLAG_NEUTRAL | SPFLAG_ESCAPE
                     | SPFLAG_RECOVERY | SPFLAG_MAPPING))
        {
            return (true);
        }

        // Things are more fun for Xom the less the player knows in
        // advance.
        if (disciplines & SPTYP_DIVINATION)
            return (true);

        // Holy spells are probably too useful for Xom to find them
        // interesting.
        if (disciplines & SPTYP_HOLY)
            return (true);
        break;

    case GOD_ELYVILON:
        // A peaceful god of healing wouldn't like combat spells.
        if (disciplines & SPTYP_CONJURATION)
            return (true);

        // Also doesn't like battle spells of the non-conjuration type.
        if (flags & SPFLAG_BATTLE)
            return (true);
        break;

    default:
        break;
    }

    return (false);
}

bool god_dislikes_spell_discipline(int discipline, god_type god)
{
    ASSERT(discipline < (1 << (SPTYP_LAST_EXPONENT + 1)));

    if (is_good_god(god) && is_evil_discipline(discipline))
        return (true);

    switch (god)
    {
    case GOD_SHINING_ONE:
        return (discipline & SPTYP_POISON);

    case GOD_YREDELEMNUL:
        return (discipline & SPTYP_HOLY);

    case GOD_XOM:
        return (discipline & (SPTYP_DIVINATION | SPTYP_HOLY));

    case GOD_ELYVILON:
        return (discipline & (SPTYP_CONJURATION | SPTYP_SUMMONING));

    default:
        break;
    }

    return (false);
}