/*
 * Copyright (C) 2016+     AzerothCore <www.azerothcore.org>, released under GNU GPL v2 license: http://github.com/azerothcore/azerothcore-wotlk/LICENSE-GPL2
 * 
 *
 * This program is free software licensed under GPL version 2
 * Please see the included DOCS/LICENSE.TXT for more information */

#include "ScriptedCreature.h"
#include "Item.h"
#include "Spell.h"
#include "GridNotifiers.h"
#include "GridNotifiersImpl.h"
#include "Cell.h"
#include "CellImpl.h"
#include "ObjectMgr.h"
#include "TemporarySummon.h"

// Spell summary for ScriptedAI::SelectSpell
struct TSpellSummary
{
    uint8 Targets;                                          // set of enum SelectTarget
    uint8 Effects;                                          // set of enum SelectEffect
} extern* SpellSummary;

void SummonList::DoZoneInCombat(uint32 entry)
{
    for (StorageType::iterator i = storage_.begin(); i != storage_.end();)
    {
        Creature* summon = ObjectAccessor::GetCreature(*me, *i);
        ++i;
        if (summon && summon->IsAIEnabled
                && (!entry || summon->GetEntry() == entry))
        {
            summon->AI()->DoZoneInCombat();
        }
    }
}

void SummonList::DespawnEntry(uint32 entry)
{
    for (StorageType::iterator i = storage_.begin(); i != storage_.end();)
    {
        Creature* summon = ObjectAccessor::GetCreature(*me, *i);
        if (!summon)
            i = storage_.erase(i);
        else if (summon->GetEntry() == entry)
        {
            i = storage_.erase(i);
            summon->DespawnOrUnsummon();
        }
        else
            ++i;
    }
}

void SummonList::DespawnAll()
{
    while (!storage_.empty())
    {
        Creature* summon = ObjectAccessor::GetCreature(*me, storage_.front());
        storage_.pop_front();
        if (summon)
            summon->DespawnOrUnsummon();
    }
}

void SummonList::RemoveNotExisting()
{
    for (StorageType::iterator i = storage_.begin(); i != storage_.end();)
    {
        if (ObjectAccessor::GetCreature(*me, *i))
            ++i;
        else
            i = storage_.erase(i);
    }
}

bool SummonList::HasEntry(uint32 entry) const
{
    for (StorageType::const_iterator i = storage_.begin(); i != storage_.end(); ++i)
    {
        Creature* summon = ObjectAccessor::GetCreature(*me, *i);
        if (summon && summon->GetEntry() == entry)
            return true;
    }

    return false;
}

uint32 SummonList::GetEntryCount(uint32 entry) const
{
    uint32 count = 0;
    for (StorageType::const_iterator i = storage_.begin(); i != storage_.end(); ++i)
    {
        Creature* summon = ObjectAccessor::GetCreature(*me, *i);
        if (summon && summon->GetEntry() == entry)
            ++count;
    }

    return count;
}

void SummonList::Respawn()
{
    for (StorageType::iterator i = storage_.begin(); i != storage_.end();)
    {
        if (Creature* summon = ObjectAccessor::GetCreature(*me, *i))
        {
            summon->Respawn(true);
            ++i;
        }
        else
            i = storage_.erase(i);
    }
}

Creature* SummonList::GetCreatureWithEntry(uint32 entry) const
{
    for (StorageType::const_iterator i = storage_.begin(); i != storage_.end(); ++i)
    {
        if (Creature* summon = ObjectAccessor::GetCreature(*me, *i))
            if (summon->GetEntry() == entry)
                return summon;
    }

    return NULL;
}

ScriptedAI::ScriptedAI(Creature* creature) : CreatureAI(creature),
    me(creature),
    IsFleeing(false),
    _evadeCheckCooldown(2500),
    _isCombatMovementAllowed(true)
{
    _isHeroic = me->GetMap()->IsHeroic();
    _difficulty = Difficulty(me->GetMap()->GetSpawnMode());
}

void ScriptedAI::AttackStartNoMove(Unit* who)
{
    if (!who)
        return;

    if (me->Attack(who, true))
        DoStartNoMovement(who);
}

void ScriptedAI::AttackStart(Unit* who)
{
    if (IsCombatMovementAllowed())
        CreatureAI::AttackStart(who);
    else
        AttackStartNoMove(who);
}

void ScriptedAI::UpdateAI(uint32 /*diff*/)
{
    //Check if we have a current target
    if (!UpdateVictim())
        return;

    DoMeleeAttackIfReady();
}

void ScriptedAI::DoStartMovement(Unit* victim, float distance, float angle)
{
    if (victim)
        me->GetMotionMaster()->MoveChase(victim, distance, angle);
}

void ScriptedAI::DoStartNoMovement(Unit* victim)
{
    if (!victim)
        return;

    me->GetMotionMaster()->MoveIdle();
}

void ScriptedAI::DoStopAttack()
{
    if (me->GetVictim())
        me->AttackStop();
}

void ScriptedAI::DoCastSpell(Unit* target, SpellInfo const* spellInfo, bool triggered)
{
    if (!target || me->IsNonMeleeSpellCast(false))
        return;

    me->StopMoving();
    me->CastSpell(target, spellInfo, triggered ? TRIGGERED_FULL_MASK : TRIGGERED_NONE);
}

void ScriptedAI::DoPlaySoundToSet(WorldObject* source, uint32 soundId)
{
    if (!source)
        return;

    if (!sSoundEntriesStore.LookupEntry(soundId))
    {
        sLog->outError("TSCR: Invalid soundId %u used in DoPlaySoundToSet (Source: TypeId %u, GUID %u)", soundId, source->GetTypeId(), source->GetGUIDLow());
        return;
    }

    source->PlayDirectSound(soundId);
}

Creature* ScriptedAI::DoSpawnCreature(uint32 entry, float offsetX, float offsetY, float offsetZ, float angle, uint32 type, uint32 despawntime)
{
    return me->SummonCreature(entry, me->GetPositionX() + offsetX, me->GetPositionY() + offsetY, me->GetPositionZ() + offsetZ, angle, TempSummonType(type), despawntime);
}

SpellInfo const* ScriptedAI::SelectSpell(Unit* target, uint32 school, uint32 mechanic, SelectTargetType targets, uint32 powerCostMin, uint32 powerCostMax, float rangeMin, float rangeMax, SelectEffect effects)
{
    //No target so we can't cast
    if (!target)
        return NULL;

    //Silenced so we can't cast
    if (me->HasFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_SILENCED))
        return NULL;

    //Using the extended script system we first create a list of viable spells
    SpellInfo const* apSpell[CREATURE_MAX_SPELLS];
    memset(apSpell, 0, CREATURE_MAX_SPELLS * sizeof(SpellInfo*));

    uint32 spellCount = 0;

    SpellInfo const* tempSpell = NULL;

    //Check if each spell is viable(set it to null if not)
    for (uint32 i = 0; i < CREATURE_MAX_SPELLS; i++)
    {
        tempSpell = sSpellMgr->GetSpellInfo(me->m_spells[i]);

        //This spell doesn't exist
        if (!tempSpell)
            continue;

        // Targets and Effects checked first as most used restrictions
        //Check the spell targets if specified
        if (targets && !(SpellSummary[me->m_spells[i]].Targets & (1 << (targets-1))))
            continue;

        //Check the type of spell if we are looking for a specific spell type
        if (effects && !(SpellSummary[me->m_spells[i]].Effects & (1 << (effects-1))))
            continue;

        //Check for school if specified
        if (school && (tempSpell->SchoolMask & school) == 0)
            continue;

        //Check for spell mechanic if specified
        if (mechanic && tempSpell->Mechanic != mechanic)
            continue;

        //Make sure that the spell uses the requested amount of power
        if (powerCostMin && tempSpell->ManaCost < powerCostMin)
            continue;

        if (powerCostMax && tempSpell->ManaCost > powerCostMax)
            continue;

        //Continue if we don't have the mana to actually cast this spell
        if (tempSpell->ManaCost > me->GetPower(Powers(tempSpell->PowerType)))
            continue;

        //Check if the spell meets our range requirements
        if (rangeMin && me->GetSpellMinRangeForTarget(target, tempSpell) < rangeMin)
            continue;
        if (rangeMax && me->GetSpellMaxRangeForTarget(target, tempSpell) > rangeMax)
            continue;

        //Check if our target is in range
        if (me->IsWithinDistInMap(target, float(me->GetSpellMinRangeForTarget(target, tempSpell))) || !me->IsWithinDistInMap(target, float(me->GetSpellMaxRangeForTarget(target, tempSpell))))
            continue;

        //All good so lets add it to the spell list
        apSpell[spellCount] = tempSpell;
        ++spellCount;
    }

    //We got our usable spells so now lets randomly pick one
    if (!spellCount)
        return NULL;

    return apSpell[urand(0, spellCount - 1)];
}

void ScriptedAI::DoResetThreat()
{
    if (!me->CanHaveThreatList() || me->getThreatManager().isThreatListEmpty())
    {
        sLog->outError("DoResetThreat called for creature that either cannot have threat list or has empty threat list (me entry = %d)", me->GetEntry());
        return;
    }

    me->getThreatManager().resetAllAggro();
}

float ScriptedAI::DoGetThreat(Unit* unit)
{
    if (!unit)
        return 0.0f;
    return me->getThreatManager().getThreat(unit);
}

void ScriptedAI::DoModifyThreatPercent(Unit* unit, int32 pct)
{
    if (!unit)
        return;
    me->getThreatManager().modifyThreatPercent(unit, pct);
}

void ScriptedAI::DoTeleportPlayer(Unit* unit, float x, float y, float z, float o)
{
    if (!unit)
        return;

    if (Player* player = unit->ToPlayer())
        player->TeleportTo(unit->GetMapId(), x, y, z, o, TELE_TO_NOT_LEAVE_COMBAT);
    else
        sLog->outError("TSCR: Creature " UI64FMTD " (Entry: %u) Tried to teleport non-player unit (Type: %u GUID: " UI64FMTD ") to x: %f y:%f z: %f o: %f. Aborted.", me->GetGUID(), me->GetEntry(), unit->GetTypeId(), unit->GetGUID(), x, y, z, o);
}

void ScriptedAI::DoTeleportAll(float x, float y, float z, float o)
{
    Map* map = me->GetMap();
    if (!map->IsDungeon())
        return;

    Map::PlayerList const& PlayerList = map->GetPlayers();
    for (Map::PlayerList::const_iterator itr = PlayerList.begin(); itr != PlayerList.end(); ++itr)
        if (Player* player = itr->GetSource())
            if (player->IsAlive())
                player->TeleportTo(me->GetMapId(), x, y, z, o, TELE_TO_NOT_LEAVE_COMBAT);
}

Unit* ScriptedAI::DoSelectLowestHpFriendly(float range, uint32 minHPDiff)
{
    Unit* unit = NULL;
    Trinity::MostHPMissingInRange u_check(me, range, minHPDiff);
    Trinity::UnitLastSearcher<Trinity::MostHPMissingInRange> searcher(me, unit, u_check);
    me->VisitNearbyObject(range, searcher);

    return unit;
}

std::list<Creature*> ScriptedAI::DoFindFriendlyCC(float range)
{
    std::list<Creature*> list;
    Trinity::FriendlyCCedInRange u_check(me, range);
    Trinity::CreatureListSearcher<Trinity::FriendlyCCedInRange> searcher(me, list, u_check);
    me->VisitNearbyObject(range, searcher);
    return list;
}

std::list<Creature*> ScriptedAI::DoFindFriendlyMissingBuff(float range, uint32 uiSpellid)
{
    std::list<Creature*> list;
    Trinity::FriendlyMissingBuffInRange u_check(me, range, uiSpellid);
    Trinity::CreatureListSearcher<Trinity::FriendlyMissingBuffInRange> searcher(me, list, u_check);
    me->VisitNearbyObject(range, searcher);
    return list;
}

Player* ScriptedAI::GetPlayerAtMinimumRange(float minimumRange)
{
    Player* player = NULL;

    CellCoord pair(Trinity::ComputeCellCoord(me->GetPositionX(), me->GetPositionY()));
    Cell cell(pair);
    cell.SetNoCreate();

    Trinity::PlayerAtMinimumRangeAway check(me, minimumRange);
    Trinity::PlayerSearcher<Trinity::PlayerAtMinimumRangeAway> searcher(me, player, check);
    TypeContainerVisitor<Trinity::PlayerSearcher<Trinity::PlayerAtMinimumRangeAway>, GridTypeMapContainer> visitor(searcher);

    cell.Visit(pair, visitor, *me->GetMap(), *me, minimumRange);

    return player;
}

void ScriptedAI::SetEquipmentSlots(bool loadDefault, int32 mainHand /*= EQUIP_NO_CHANGE*/, int32 offHand /*= EQUIP_NO_CHANGE*/, int32 ranged /*= EQUIP_NO_CHANGE*/)
{
    if (loadDefault)
    {
        me->LoadEquipment(me->GetOriginalEquipmentId(), true);
        return;
    }

    if (mainHand >= 0)
        me->SetUInt32Value(UNIT_VIRTUAL_ITEM_SLOT_ID + 0, uint32(mainHand));

    if (offHand >= 0)
        me->SetUInt32Value(UNIT_VIRTUAL_ITEM_SLOT_ID + 1, uint32(offHand));

    if (ranged >= 0)
        me->SetUInt32Value(UNIT_VIRTUAL_ITEM_SLOT_ID + 2, uint32(ranged));
}

void ScriptedAI::SetCombatMovement(bool allowMovement)
{
    _isCombatMovementAllowed = allowMovement;
}

enum eNPCs
{
    NPC_BROODLORD   = 12017,
    NPC_JAN_ALAI    = 23578,
    NPC_SARTHARION  = 28860,
    NPC_FREYA       = 32906,
};

bool ScriptedAI::EnterEvadeIfOutOfCombatArea()
{
    if (me->IsInEvadeMode() || !me->IsInCombat())
        return false;

    if (_evadeCheckCooldown == time(NULL))
        return false;
    _evadeCheckCooldown = time(NULL);

    if (!CheckEvadeIfOutOfCombatArea())
        return false;

    EnterEvadeMode();
    return true;
}

Player* ScriptedAI::SelectTargetFromPlayerList(float maxdist, uint32 excludeAura, bool mustBeInLOS) const
{
    Map::PlayerList const& pList = me->GetMap()->GetPlayers();
    std::vector<Player*> tList;
    for(Map::PlayerList::const_iterator itr = pList.begin(); itr != pList.end(); ++itr)
    {
        if (me->GetDistance(itr->GetSource()) > maxdist || !itr->GetSource()->IsAlive() || itr->GetSource()->IsGameMaster())
            continue;
        if (excludeAura && itr->GetSource()->HasAura(excludeAura))
            continue;
        if (mustBeInLOS && !me->IsWithinLOSInMap(itr->GetSource()))
            continue;
        tList.push_back(itr->GetSource());
    }
    if (!tList.empty())
        return tList[urand(0,tList.size()-1)];
    else
        return NULL;
}

// BossAI - for instanced bosses

BossAI::BossAI(Creature* creature, uint32 bossId) : ScriptedAI(creature),
    instance(creature->GetInstanceScript()),
    summons(creature),
    _boundary(instance ? instance->GetBossBoundary(bossId) : NULL),
    _bossId(bossId)
{
}

void BossAI::_Reset()
{
    if (!me->IsAlive())
        return;

    me->ResetLootMode();
    events.Reset();
    summons.DespawnAll();
    if (instance)
        instance->SetBossState(_bossId, NOT_STARTED);
}

void BossAI::_JustDied()
{
    events.Reset();
    summons.DespawnAll();
    if (instance)
    {
        instance->SetBossState(_bossId, DONE);
        instance->SaveToDB();
    }
}

void BossAI::_EnterCombat()
{
    me->setActive(true);
    DoZoneInCombat();
    if (instance)
    {
        // bosses do not respawn, check only on enter combat
        if (!instance->CheckRequiredBosses(_bossId))
        {
            EnterEvadeMode();
            return;
        }
        instance->SetBossState(_bossId, IN_PROGRESS);
    }
}

void BossAI::TeleportCheaters()
{
    float x, y, z;
    me->GetPosition(x, y, z);

    ThreatContainer::StorageType threatList = me->getThreatManager().getThreatList();
    for (ThreatContainer::StorageType::const_iterator itr = threatList.begin(); itr != threatList.end(); ++itr)
        if (Unit* target = (*itr)->getTarget())
            if (target->GetTypeId() == TYPEID_PLAYER && !CheckBoundary(target))
                target->NearTeleportTo(x, y, z, 0);
}

bool BossAI::CheckBoundary(Unit* who)
{
    if (!GetBoundary() || !who)
        return true;

    for (BossBoundaryMap::const_iterator itr = GetBoundary()->begin(); itr != GetBoundary()->end(); ++itr)
    {
        switch (itr->first)
        {
            case BOUNDARY_N:
                if (who->GetPositionX() > itr->second)
                    return false;
                break;
            case BOUNDARY_S:
                if (who->GetPositionX() < itr->second)
                    return false;
                break;
            case BOUNDARY_E:
                if (who->GetPositionY() < itr->second)
                    return false;
                break;
            case BOUNDARY_W:
                if (who->GetPositionY() > itr->second)
                    return false;
                break;
            case BOUNDARY_NW:
                if (who->GetPositionX() + who->GetPositionY() > itr->second)
                    return false;
                break;
            case BOUNDARY_SE:
                if (who->GetPositionX() + who->GetPositionY() < itr->second)
                    return false;
                break;
            case BOUNDARY_NE:
                if (who->GetPositionX() - who->GetPositionY() > itr->second)
                    return false;
                break;
            case BOUNDARY_SW:
                if (who->GetPositionX() - who->GetPositionY() < itr->second)
                    return false;
                break;
            default:
                break;
        }
    }

    return true;
}

void BossAI::JustSummoned(Creature* summon)
{
    summons.Summon(summon);
    if (me->IsInCombat())
        DoZoneInCombat(summon);
}

void BossAI::SummonedCreatureDespawn(Creature* summon)
{
    summons.Despawn(summon);
}

void BossAI::UpdateAI(uint32 diff)
{
    if (!UpdateVictim())
        return;

    events.Update(diff);

    if (me->HasUnitState(UNIT_STATE_CASTING))
        return;

    while (uint32 eventId = events.ExecuteEvent())
        ExecuteEvent(eventId);

    DoMeleeAttackIfReady();
}

// WorldBossAI - for non-instanced bosses

WorldBossAI::WorldBossAI(Creature* creature) :
    ScriptedAI(creature),
    summons(creature)
{
}

void WorldBossAI::_Reset()
{
    if (!me->IsAlive())
        return;

    events.Reset();
    summons.DespawnAll();
}

void WorldBossAI::_JustDied()
{
    events.Reset();
    summons.DespawnAll();
}

void WorldBossAI::_EnterCombat()
{
    Unit* target = SelectTarget(SELECT_TARGET_RANDOM, 0, 0.0f, true);
    if (target)
        AttackStart(target);
}

void WorldBossAI::JustSummoned(Creature* summon)
{
    summons.Summon(summon);
    Unit* target = SelectTarget(SELECT_TARGET_RANDOM, 0, 0.0f, true);
    if (target)
        summon->AI()->AttackStart(target);
}

void WorldBossAI::SummonedCreatureDespawn(Creature* summon)
{
    summons.Despawn(summon);
}

void WorldBossAI::UpdateAI(uint32 diff)
{
    if (!UpdateVictim())
        return;

    events.Update(diff);

    if (me->HasUnitState(UNIT_STATE_CASTING))
        return;

    while (uint32 eventId = events.ExecuteEvent())
        ExecuteEvent(eventId);

    DoMeleeAttackIfReady();
}

// SD2 grid searchers.
Creature* GetClosestCreatureWithEntry(WorldObject* source, uint32 entry, float maxSearchRange, bool alive /*= true*/)
{
    return source->FindNearestCreature(entry, maxSearchRange, alive);
}

GameObject* GetClosestGameObjectWithEntry(WorldObject* source, uint32 entry, float maxSearchRange)
{
    return source->FindNearestGameObject(entry, maxSearchRange);
}

void GetCreatureListWithEntryInGrid(std::list<Creature*>& list, WorldObject* source, uint32 entry, float maxSearchRange)
{
    source->GetCreatureListWithEntryInGrid(list, entry, maxSearchRange);
}

void GetGameObjectListWithEntryInGrid(std::list<GameObject*>& list, WorldObject* source, uint32 entry, float maxSearchRange)
{
    source->GetGameObjectListWithEntryInGrid(list, entry, maxSearchRange);
}
