/*
 * Copyright (C) 2005-2009 MaNGOS <http://getmangos.com/>
 *
 * Copyright (C) 2008-2009 Trinity <http://www.trinitycore.org/>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "CreatureAI.h"
#include "CreatureAIImpl.h"
#include "Creature.h"
#include "World.h"
#include "SpellMgr.h"

//Disable CreatureAI when charmed
void CreatureAI::OnCharmed(bool apply)
{
    //me->IsAIEnabled = !apply;*/
    me->NeedChangeAI = true;
    me->IsAIEnabled = false;
}

AISpellInfoType * UnitAI::AISpellInfo;
TRINITY_DLL_SPEC AISpellInfoType * GetAISpellInfo(uint32 i) { return &CreatureAI::AISpellInfo[i]; }

void CreatureAI::DoZoneInCombat(Creature* creature)
{
    if (!creature)
        creature = me;

    if(!creature->CanHaveThreatList())
        return;

    Map *map = creature->GetMap();
    if (!map->IsDungeon())                                  //use IsDungeon instead of Instanceable, in case battlegrounds will be instantiated
    {
        sLog.outError("DoZoneInCombat call for map that isn't an instance (creature entry = %d)", creature->GetTypeId() == TYPEID_UNIT ? ((Creature*)creature)->GetEntry() : 0);
        return;
    }

    if(!creature->HasReactState(REACT_PASSIVE) && !creature->getVictim())
    {
        if(Unit *target = creature->SelectNearestTarget(50))
            creature->AI()->AttackStart(target);
        else if(creature->isSummon())
        {
            if(Unit *summoner = ((TempSummon*)creature)->GetSummoner())
            {
                Unit *target = summoner->getAttackerForHelper();
                if(!target && summoner->CanHaveThreatList() && !summoner->getThreatManager().isThreatListEmpty())
                    target = summoner->getThreatManager().getHostilTarget();
                if(target && (creature->IsFriendlyTo(summoner) || creature->IsHostileTo(target)))
                    creature->AI()->AttackStart(target);
            }
        }
    }

    if(!creature->HasReactState(REACT_PASSIVE) && !creature->getVictim())
    {
        sLog.outError("DoZoneInCombat called for creature that has empty threat list (creature entry = %u)", creature->GetEntry());
        return;
    }

    Map::PlayerList const &PlList = map->GetPlayers();

    if(PlList.isEmpty())
        return;

    for(Map::PlayerList::const_iterator i = PlList.begin(); i != PlList.end(); ++i)
    {
        if(Player* pPlayer = i->getSource())
        {
            if(pPlayer->isGameMaster())
                continue;

            if(pPlayer->isAlive())
            {
                creature->SetInCombatWith(pPlayer);
                pPlayer->SetInCombatWith(creature);
                creature->AddThreat(pPlayer, 0.0f);
            }
        }
    }
}

void CreatureAI::MoveInLineOfSight(Unit *who)
{
    if(me->getVictim())
        return;

    if(me->canStartAttack(who, false))
        AttackStart(who);
    else if(who->getVictim() && me->IsFriendlyTo(who)
        && me->IsWithinDistInMap(who, sWorld.getConfig(CONFIG_CREATURE_FAMILY_ASSISTANCE_RADIUS))
        && me->canStartAttack(who->getVictim(), true))
        AttackStart(who->getVictim());
}

void CreatureAI::SelectNearestTarget(Unit *who)
{
    if(me->getVictim() && me->GetDistanceOrder(who, me->getVictim()) && me->canAttack(who))
    {
        me->getThreatManager().modifyThreatPercent(me->getVictim(), -100);
        me->AddThreat(who, 1000000.0f);
    }
}

void CreatureAI::SetGazeOn(Unit *target)
{
    if(me->canAttack(target))
    {
        AttackStart(target);
        me->SetReactState(REACT_PASSIVE);
    }
}

bool CreatureAI::UpdateVictimWithGaze()
{
    if(!me->isInCombat())
        return false;

    if(me->HasReactState(REACT_PASSIVE))
    {
        if(me->getVictim())
            return true;
        else
            me->SetReactState(REACT_AGGRESSIVE);
    }

    if(Unit *victim = me->SelectVictim())
        AttackStart(victim);
    return me->getVictim();
}

bool CreatureAI::UpdateVictim()
{
    if(!me->isInCombat())
        return false;

    if(Unit *victim = me->SelectVictim())
        AttackStart(victim);
    return me->getVictim();
}

bool CreatureAI::UpdateCombatState()
{
    if(!me->isInCombat())
        return false;

    if(!me->HasReactState(REACT_PASSIVE))
    {
        if(Unit *victim = me->SelectVictim())
            AttackStart(victim);
        return me->getVictim();
    }
    else if(me->getThreatManager().isThreatListEmpty())
    {
        EnterEvadeMode();
        return false;
    }

    return true;
}

bool CreatureAI::_EnterEvadeMode()
{
    if(me->IsInEvadeMode() || !me->isAlive())
        return false;

    me->RemoveAllAuras();
    me->DeleteThreatList();
    me->CombatStop(true);
    me->LoadCreaturesAddon();
    me->SetLootRecipient(NULL);
    me->ResetPlayerDamageReq();

    return true;
}

void CreatureAI::EnterEvadeMode()
{
    if(!_EnterEvadeMode())
        return;

    if(Unit *owner = me->GetCharmerOrOwner())
        me->GetMotionMaster()->MoveFollow(owner, PET_FOLLOW_DIST, PET_FOLLOW_ANGLE, MOTION_SLOT_IDLE);
    else
        me->GetMotionMaster()->MoveTargetedHome();

    Reset();
}

/*void CreatureAI::AttackedBy( Unit* attacker )
{
    if(!m_creature->getVictim())
        AttackStart(attacker);
}*/