/*
 * This file is part of the L2J Mobius project.
 * 
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */
package com.l2jmobius.gameserver.ai;

import static com.l2jmobius.gameserver.ai.CtrlIntention.AI_INTENTION_ACTIVE;
import static com.l2jmobius.gameserver.ai.CtrlIntention.AI_INTENTION_ATTACK;
import static com.l2jmobius.gameserver.ai.CtrlIntention.AI_INTENTION_IDLE;

import java.util.Comparator;
import java.util.List;
import java.util.Set;
import java.util.concurrent.Future;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.stream.Stream;

import com.l2jmobius.Config;
import com.l2jmobius.commons.util.Rnd;
import com.l2jmobius.gameserver.GameTimeController;
import com.l2jmobius.gameserver.GeoData;
import com.l2jmobius.gameserver.ThreadPoolManager;
import com.l2jmobius.gameserver.enums.AISkillScope;
import com.l2jmobius.gameserver.model.AggroInfo;
import com.l2jmobius.gameserver.model.L2Object;
import com.l2jmobius.gameserver.model.L2World;
import com.l2jmobius.gameserver.model.Location;
import com.l2jmobius.gameserver.model.actor.L2Attackable;
import com.l2jmobius.gameserver.model.actor.L2Character;
import com.l2jmobius.gameserver.model.actor.L2Npc;
import com.l2jmobius.gameserver.model.actor.L2Playable;
import com.l2jmobius.gameserver.model.actor.instance.L2GrandBossInstance;
import com.l2jmobius.gameserver.model.actor.instance.L2GuardInstance;
import com.l2jmobius.gameserver.model.actor.instance.L2MonsterInstance;
import com.l2jmobius.gameserver.model.actor.instance.L2PcInstance;
import com.l2jmobius.gameserver.model.actor.instance.L2RaidBossInstance;
import com.l2jmobius.gameserver.model.effects.L2EffectType;
import com.l2jmobius.gameserver.model.events.EventDispatcher;
import com.l2jmobius.gameserver.model.events.impl.character.npc.OnAttackableFactionCall;
import com.l2jmobius.gameserver.model.events.impl.character.npc.OnAttackableHate;
import com.l2jmobius.gameserver.model.events.returns.TerminateReturn;
import com.l2jmobius.gameserver.model.items.instance.L2ItemInstance;
import com.l2jmobius.gameserver.model.skills.BuffInfo;
import com.l2jmobius.gameserver.model.skills.Skill;
import com.l2jmobius.gameserver.model.skills.SkillCaster;
import com.l2jmobius.gameserver.model.zone.ZoneId;

/**
 * This class manages AI of L2Attackable.
 */
public class L2AttackableAI extends L2CharacterAI implements Runnable
{
	private static final Logger LOGGER = Logger.getLogger(L2AttackableAI.class.getName());
	
	private static final int RANDOM_WALK_RATE = 30; // confirmed
	// private static final int MAX_DRIFT_RANGE = 300;
	private static final int MAX_ATTACK_TIMEOUT = 1200; // int ticks, i.e. 2min
	/**
	 * The L2Attackable AI task executed every 1s (call onEvtThink method).
	 */
	private Future<?> _aiTask;
	/**
	 * The delay after which the attacked is stopped.
	 */
	private int _attackTimeout;
	/**
	 * The L2Attackable aggro counter.
	 */
	private int _globalAggro;
	/**
	 * The flag used to indicate that a thinking action is in progress, to prevent recursive thinking.
	 */
	private boolean _thinking;
	
	private int chaostime = 0;
	int lastBuffTick;
	
	public L2AttackableAI(L2Attackable attackable)
	{
		super(attackable);
		_attackTimeout = Integer.MAX_VALUE;
		_globalAggro = -10; // 10 seconds timeout of ATTACK after respawn
	}
	
	@Override
	public void run()
	{
		// Launch actions corresponding to the Event Think
		onEvtThink();
	}
	
	/**
	 * @param target The targeted WorldObject
	 * @return {@code true} if target can be auto attacked due aggression.
	 */
	private boolean isAggressiveTowards(L2Character target)
	{
		if ((target == null) || (getActiveChar() == null))
		{
			return false;
		}
		
		// Check if the target isn't invulnerable
		if (target.isInvul())
		{
			return false;
		}
		
		// Check if the target isn't a Folk or a Door
		if (target.isDoor())
		{
			return false;
		}
		
		final L2Attackable me = getActiveChar();
		
		// Check if the target isn't dead, is in the Aggro range and is at the same height
		if (target.isAlikeDead())
		{
			return false;
		}
		
		// Check if the target is a L2Playable
		if (target.isPlayable())
		{
			// Check if the AI isn't a Raid Boss, can See Silent Moving players and the target isn't in silent move mode
			if (!(me.isRaid()) && !(me.canSeeThroughSilentMove()) && ((L2Playable) target).isSilentMovingAffected())
			{
				return false;
			}
		}
		
		// Gets the player if there is any.
		final L2PcInstance player = target.getActingPlayer();
		if (player != null)
		{
			// Don't take the aggro if the GM has the access level below or equal to GM_DONT_TAKE_AGGRO
			if (!player.getAccessLevel().canTakeAggro())
			{
				return false;
			}
			
			// check if the target is within the grace period for JUST getting up from fake death
			if (player.isRecentFakeDeath())
			{
				return false;
			}
		}
		else if (me.isMonster())
		{
			// depending on config, do not allow mobs to attack _new_ players in peacezones,
			// unless they are already following those players from outside the peacezone.
			if (!Config.ALT_MOB_AGRO_IN_PEACEZONE && target.isInsideZone(ZoneId.PEACE))
			{
				return false;
			}
			
			if (me.isChampion() && Config.L2JMOD_CHAMPION_PASSIVE)
			{
				return false;
			}
			
			if (!me.isAggressive())
			{
				return false;
			}
		}
		
		return target.isAutoAttackable(me) && GeoData.getInstance().canSeeTarget(me, target);
	}
	
	public void startAITask()
	{
		// If not idle - create an AI task (schedule onEvtThink repeatedly)
		if (_aiTask == null)
		{
			_aiTask = ThreadPoolManager.getInstance().scheduleAiAtFixedRate(this, 1000, 1000);
		}
	}
	
	@Override
	public void stopAITask()
	{
		if (_aiTask != null)
		{
			_aiTask.cancel(false);
			_aiTask = null;
		}
		super.stopAITask();
	}
	
	/**
	 * Set the Intention of this L2CharacterAI and create an AI Task executed every 1s (call onEvtThink method) for this L2Attackable.<br>
	 * <FONT COLOR=#FF0000><B> <U>Caution</U> : If actor _knowPlayer isn't EMPTY, AI_INTENTION_IDLE will be change in AI_INTENTION_ACTIVE</B></FONT>
	 * @param intention The new Intention to set to the AI
	 * @param args The first parameter of the Intention
	 */
	@Override
	synchronized void changeIntention(CtrlIntention intention, Object... args)
	{
		if ((intention == AI_INTENTION_IDLE) || (intention == AI_INTENTION_ACTIVE))
		{
			// Check if actor is not dead
			final L2Attackable npc = getActiveChar();
			if (!npc.isAlikeDead())
			{
				// If its _knownPlayer isn't empty set the Intention to AI_INTENTION_ACTIVE
				if (!L2World.getInstance().getVisibleObjects(npc, L2PcInstance.class).isEmpty())
				{
					intention = AI_INTENTION_ACTIVE;
				}
				else
				{
					if (npc.getSpawn() != null)
					{
						final Location loc = npc.getSpawn().getLocation();
						final int range = Config.MAX_DRIFT_RANGE;
						
						if (!npc.isInsideRadius(loc, range + range, true, false))
						{
							intention = AI_INTENTION_ACTIVE;
						}
					}
				}
			}
			
			if (intention == AI_INTENTION_IDLE)
			{
				// Set the Intention of this L2AttackableAI to AI_INTENTION_IDLE
				super.changeIntention(AI_INTENTION_IDLE);
				
				stopAITask();
				
				// Cancel the AI
				_actor.detachAI();
				
				return;
			}
		}
		
		// Set the Intention of this L2AttackableAI to intention
		super.changeIntention(intention, args);
		
		// If not idle - create an AI task (schedule onEvtThink repeatedly)
		startAITask();
	}
	
	@Override
	protected void changeIntentionToCast(Skill skill, L2Object target, L2ItemInstance item, boolean forceUse, boolean dontMove)
	{
		// Set the AI cast target
		setTarget(target);
		super.changeIntentionToCast(skill, target, item, forceUse, dontMove);
	}
	
	/**
	 * Manage the Attack Intention : Stop current Attack (if necessary), Calculate attack timeout, Start a new Attack and Launch Think Event.
	 * @param target The L2Character to attack
	 */
	@Override
	protected void onIntentionAttack(L2Character target)
	{
		// Calculate the attack timeout
		_attackTimeout = MAX_ATTACK_TIMEOUT + GameTimeController.getInstance().getGameTicks();
		
		// self and buffs
		if ((lastBuffTick + 30) < GameTimeController.getInstance().getGameTicks())
		{
			for (Skill buff : getActiveChar().getTemplate().getAISkills(AISkillScope.BUFF))
			{
				target = skillTargetReconsider(buff, true);
				if (target != null)
				{
					setTarget(target);
					_actor.doCast(buff);
					LOGGER.finer(this + " used buff skill " + buff + " on " + _actor);
					break;
				}
			}
			lastBuffTick = GameTimeController.getInstance().getGameTicks();
		}
		
		// Manage the Attack Intention : Stop current Attack (if necessary), Start a new Attack and Launch Think Event
		super.onIntentionAttack(target);
	}
	
	protected void thinkCast()
	{
		final L2Object target = _skill.getTarget(_actor, getTarget(), _forceUse, _dontMove, false);
		if (checkTargetLost(target))
		{
			return;
		}
		if (maybeMoveToPawn(target, _actor.getMagicalAttackRange(_skill)))
		{
			return;
		}
		setIntention(AI_INTENTION_ACTIVE);
		_actor.doCast(_skill, _item, _forceUse, _dontMove);
	}
	
	/**
	 * Manage AI standard thinks of a L2Attackable (called by onEvtThink). <B><U> Actions</U> :</B>
	 * <ul>
	 * <li>Update every 1s the _globalAggro counter to come close to 0</li>
	 * <li>If the actor is Aggressive and can attack, add all autoAttackable L2Character in its Aggro Range to its _aggroList, chose a target and order to attack it</li>
	 * <li>If the actor is a L2GuardInstance that can't attack, order to it to return to its home location</li>
	 * <li>If the actor is a L2MonsterInstance that can't attack, order to it to random walk (1/100)</li>
	 * </ul>
	 */
	protected void thinkActive()
	{
		final L2Attackable npc = getActiveChar();
		L2Object target = getTarget();
		// Update every 1s the _globalAggro counter to come close to 0
		if (_globalAggro != 0)
		{
			if (_globalAggro < 0)
			{
				_globalAggro++;
			}
			else
			{
				_globalAggro--;
			}
		}
		
		// Add all autoAttackable L2Character in L2Attackable Aggro Range to its _aggroList with 0 damage and 1 hate
		// A L2Attackable isn't aggressive during 10s after its spawn because _globalAggro is set to -10
		if (_globalAggro >= 0)
		{
			if (npc.isAggressive() || (npc instanceof L2GuardInstance))
			{
				final int range = npc instanceof L2GuardInstance ? 500 : npc.getAggroRange(); // TODO Make sure how guards behave towards players.
				L2World.getInstance().forEachVisibleObjectInRange(npc, L2Character.class, range, t ->
				{
					// For each L2Character check if the target is autoattackable
					if (isAggressiveTowards(t)) // check aggression
					{
						if (t.isPlayable())
						{
							final TerminateReturn term = EventDispatcher.getInstance().notifyEvent(new OnAttackableHate(getActiveChar(), t.getActingPlayer(), t.isSummon()), getActiveChar(), TerminateReturn.class);
							if ((term != null) && term.terminate())
							{
								return;
							}
						}
						
						// Get the hate level of the L2Attackable against this L2Character target contained in _aggroList
						final int hating = npc.getHating(t);
						
						// Add the attacker to the L2Attackable _aggroList with 0 damage and 1 hate
						if (hating == 0)
						{
							npc.addDamageHate(t, 0, 1);
						}
					}
				});
			}
			
			// Chose a target from its aggroList
			L2Character hated;
			if (npc.isConfused() && (target != null) && target.isCharacter())
			{
				hated = (L2Character) target; // effect handles selection
			}
			else
			{
				hated = npc.getMostHated();
			}
			
			// Order to the L2Attackable to attack the target
			if ((hated != null) && !npc.isCoreAIDisabled())
			{
				// Get the hate level of the L2Attackable against this L2Character target contained in _aggroList
				final int aggro = npc.getHating(hated);
				
				if ((aggro + _globalAggro) > 0)
				{
					// Set the L2Character movement type to run and send Server->Client packet ChangeMoveType to all others L2PcInstance
					if (!npc.isRunning())
					{
						npc.setRunning();
					}
					
					// Set the AI Intention to AI_INTENTION_ATTACK
					setIntention(CtrlIntention.AI_INTENTION_ATTACK, hated);
				}
				
				return;
			}
		}
		
		// Chance to forget attackers after some time
		if ((npc.getCurrentHp() == npc.getMaxHp()) && (npc.getCurrentMp() == npc.getMaxMp()) && !npc.getAttackByList().isEmpty() && (Rnd.nextInt(500) == 0) && npc.canStopAttackByTime())
		{
			npc.clearAggroList();
			npc.getAttackByList().clear();
			if (npc.isMonster())
			{
				if (((L2MonsterInstance) npc).hasMinions())
				{
					((L2MonsterInstance) npc).getMinionList().deleteReusedMinions();
				}
			}
		}
		
		// Check if the mob should not return to spawn point
		if (!npc.canReturnToSpawnPoint())
		{
			return;
		}
		
		// Check if the actor is a L2GuardInstance
		if ((npc instanceof L2GuardInstance) && !npc.isWalker())
		{
			// Order to the L2GuardInstance to return to its home location because there's no target to attack
			npc.returnHome();
		}
		
		// Minions following leader
		final L2Character leader = npc.getLeader();
		if ((leader != null) && !leader.isAlikeDead())
		{
			final int offset;
			final int minRadius = 30;
			
			if (npc.isRaidMinion())
			{
				offset = 500; // for Raids - need correction
			}
			else
			{
				offset = 200; // for normal minions - need correction :)
			}
			
			if (leader.isRunning())
			{
				npc.setRunning();
			}
			else
			{
				npc.setWalking();
			}
			
			if (npc.calculateDistance(leader, false, true) > (offset * offset))
			{
				int x1, y1, z1;
				x1 = Rnd.get(minRadius * 2, offset * 2); // x
				y1 = Rnd.get(x1, offset * 2); // distance
				y1 = (int) Math.sqrt((y1 * y1) - (x1 * x1)); // y
				if (x1 > (offset + minRadius))
				{
					x1 = (leader.getX() + x1) - offset;
				}
				else
				{
					x1 = (leader.getX() - x1) + minRadius;
				}
				if (y1 > (offset + minRadius))
				{
					y1 = (leader.getY() + y1) - offset;
				}
				else
				{
					y1 = (leader.getY() - y1) + minRadius;
				}
				
				z1 = leader.getZ();
				// Move the actor to Location (x,y,z) server side AND client side by sending Server->Client packet CharMoveToLocation (broadcast)
				moveTo(x1, y1, z1);
				return;
			}
			else if (Rnd.nextInt(RANDOM_WALK_RATE) == 0)
			{
				for (Skill sk : npc.getTemplate().getAISkills(AISkillScope.BUFF))
				{
					target = skillTargetReconsider(sk, true);
					if (target != null)
					{
						setTarget(target);
						npc.doCast(sk);
						return;
					}
				}
			}
		}
		// Order to the L2MonsterInstance to random walk (1/100)
		else if ((npc.getSpawn() != null) && (Rnd.nextInt(RANDOM_WALK_RATE) == 0) && npc.isRandomWalkingEnabled())
		{
			int x1 = 0;
			int y1 = 0;
			int z1 = 0;
			final int range = Config.MAX_DRIFT_RANGE;
			
			for (Skill sk : npc.getTemplate().getAISkills(AISkillScope.BUFF))
			{
				target = skillTargetReconsider(sk, true);
				if (target != null)
				{
					setTarget(target);
					npc.doCast(sk);
					return;
				}
			}
			
			x1 = npc.getSpawn().getX();
			y1 = npc.getSpawn().getY();
			z1 = npc.getSpawn().getZ();
			
			if (!npc.isInsideRadius(x1, y1, 0, range, false, false))
			{
				npc.setisReturningToSpawnPoint(true);
			}
			else
			{
				final int deltaX = Rnd.nextInt(range * 2); // x
				int deltaY = Rnd.get(deltaX, range * 2); // distance
				deltaY = (int) Math.sqrt((deltaY * deltaY) - (deltaX * deltaX)); // y
				x1 = (deltaX + x1) - range;
				y1 = (deltaY + y1) - range;
				z1 = npc.getZ();
			}
			
			// Move the actor to Location (x,y,z) server side AND client side by sending Server->Client packet CharMoveToLocation (broadcast)
			final Location moveLoc = GeoData.getInstance().moveCheck(npc.getX(), npc.getY(), npc.getZ(), x1, y1, z1, npc.getInstanceWorld());
			
			moveTo(moveLoc.getX(), moveLoc.getY(), moveLoc.getZ());
		}
	}
	
	/**
	 * Manage AI attack thinks of a L2Attackable (called by onEvtThink). <B><U> Actions</U> :</B>
	 * <ul>
	 * <li>Update the attack timeout if actor is running</li>
	 * <li>If target is dead or timeout is expired, stop this attack and set the Intention to AI_INTENTION_ACTIVE</li>
	 * <li>Call all L2Object of its Faction inside the Faction Range</li>
	 * <li>Chose a target and order to attack it with magic skill or physical attack</li>
	 * </ul>
	 * TODO: Manage casting rules to healer mobs (like Ant Nurses)
	 */
	protected void thinkAttack()
	{
		final L2Attackable npc = getActiveChar();
		
		if (npc.isCastingNow())
		{
			return;
		}
		
		L2Character target = npc.getMostHated();
		if (getTarget() != target)
		{
			setTarget(target);
		}
		
		// Check if target is dead or if timeout is expired to stop this attack
		if ((target == null) || target.isAlikeDead() || ((_attackTimeout < GameTimeController.getInstance().getGameTicks()) && npc.canStopAttackByTime()))
		{
			// Stop hating this target after the attack timeout or if target is dead
			npc.stopHating(target);
			
			// Set the AI Intention to AI_INTENTION_ACTIVE
			setIntention(AI_INTENTION_ACTIVE);
			
			npc.setWalking();
			return;
		}
		
		final int collision = npc.getTemplate().getCollisionRadius();
		
		// Handle all L2Object of its Faction inside the Faction Range
		
		final Set<Integer> clans = getActiveChar().getTemplate().getClans();
		if ((clans != null) && !clans.isEmpty())
		{
			final int factionRange = npc.getTemplate().getClanHelpRange() + collision;
			// Go through all L2Object that belong to its faction
			try
			{
				final L2Character finalTarget = target;
				L2World.getInstance().forEachVisibleObjectInRange(npc, L2Npc.class, factionRange, called ->
				{
					if (!getActiveChar().getTemplate().isClan(called.getTemplate().getClans()))
					{
						return;
					}
					
					// Check if the L2Object is inside the Faction Range of the actor
					if (called.hasAI())
					{
						if ((Math.abs(finalTarget.getZ() - called.getZ()) < 600) && npc.getAttackByList().contains(finalTarget) && ((called.getAI()._intention == CtrlIntention.AI_INTENTION_IDLE) || (called.getAI()._intention == CtrlIntention.AI_INTENTION_ACTIVE)))
						{
							if (finalTarget.isPlayable())
							{
								// By default, when a faction member calls for help, attack the caller's attacker.
								// Notify the AI with EVT_AGGRESSION
								called.getAI().notifyEvent(CtrlEvent.EVT_AGGRESSION, finalTarget, 1);
								EventDispatcher.getInstance().notifyEventAsync(new OnAttackableFactionCall(called, getActiveChar(), finalTarget.getActingPlayer(), finalTarget.isSummon()), called);
							}
							else if (called.isAttackable() && (called.getAI()._intention != CtrlIntention.AI_INTENTION_ATTACK))
							{
								((L2Attackable) called).addDamageHate(finalTarget, 0, npc.getHating(finalTarget));
								called.getAI().setIntention(CtrlIntention.AI_INTENTION_ATTACK, finalTarget);
							}
						}
					}
				});
			}
			catch (NullPointerException e)
			{
				LOGGER.warning(getClass().getSimpleName() + ": thinkAttack() faction call failed: " + e.getMessage());
			}
		}
		
		if (npc.isCoreAIDisabled())
		{
			return;
		}
		
		final int combinedCollision = collision + target.getTemplate().getCollisionRadius();
		
		final List<Skill> aiSuicideSkills = npc.getTemplate().getAISkills(AISkillScope.SUICIDE);
		if (!aiSuicideSkills.isEmpty() && ((int) ((npc.getCurrentHp() / npc.getMaxHp()) * 100) < 30) && npc.hasSkillChance())
		{
			final Skill skill = aiSuicideSkills.get(Rnd.get(aiSuicideSkills.size()));
			if (SkillCaster.checkUseConditions(npc, skill) && checkSkillTarget(skill, target))
			{
				npc.doCast(skill);
				LOGGER.finer(this + " used suicide skill " + skill);
				return;
			}
		}
		
		// ------------------------------------------------------
		// In case many mobs are trying to hit from same place, move a bit, circling around the target
		// Note from Gnacik:
		// On l2js because of that sometimes mobs don't attack player only running around player without any sense, so decrease chance for now
		if (!npc.isMovementDisabled() && (Rnd.nextInt(100) <= 3))
		{
			for (L2Attackable nearby : L2World.getInstance().getVisibleObjects(npc, L2Attackable.class))
			{
				if (npc.isInsideRadius(nearby, collision, false, false) && (nearby != target))
				{
					int newX = combinedCollision + Rnd.get(40);
					if (Rnd.nextBoolean())
					{
						newX = target.getX() + newX;
					}
					else
					{
						newX = target.getX() - newX;
					}
					int newY = combinedCollision + Rnd.get(40);
					if (Rnd.nextBoolean())
					{
						newY = target.getY() + newY;
					}
					else
					{
						newY = target.getY() - newY;
					}
					
					if (!npc.isInsideRadius(newX, newY, 0, collision, false, false))
					{
						final int newZ = npc.getZ() + 30;
						if (GeoData.getInstance().canMove(npc, newX, newY, newZ))
						{
							moveTo(newX, newY, newZ);
						}
					}
					return;
				}
			}
		}
		// Dodge if its needed
		if (!npc.isMovementDisabled() && (npc.getTemplate().getDodge() > 0))
		{
			if (Rnd.get(100) <= npc.getTemplate().getDodge())
			{
				// Micht: kepping this one otherwise we should do 2 sqrt
				final double distance2 = npc.calculateDistance(target, false, true);
				if (Math.sqrt(distance2) <= (60 + combinedCollision))
				{
					int posX = npc.getX();
					int posY = npc.getY();
					final int posZ = npc.getZ() + 30;
					
					if (target.getX() < posX)
					{
						posX = posX + 300;
					}
					else
					{
						posX = posX - 300;
					}
					
					if (target.getY() < posY)
					{
						posY = posY + 300;
					}
					else
					{
						posY = posY - 300;
					}
					
					if (GeoData.getInstance().canMove(npc, posX, posY, posZ))
					{
						setIntention(CtrlIntention.AI_INTENTION_MOVE_TO, new Location(posX, posY, posZ, 0));
					}
					return;
				}
			}
		}
		
		// ------------------------------------------------------------------------------
		// BOSS/Raid Minion Target Reconsider
		if (npc.isRaid() || npc.isRaidMinion())
		{
			chaostime++;
			boolean changeTarget = false;
			if ((npc instanceof L2RaidBossInstance) && (chaostime > Config.RAID_CHAOS_TIME))
			{
				final double multiplier = ((L2MonsterInstance) npc).hasMinions() ? 200 : 100;
				changeTarget = Rnd.get(100) <= (100 - ((npc.getCurrentHp() * multiplier) / npc.getMaxHp()));
			}
			else if ((npc instanceof L2GrandBossInstance) && (chaostime > Config.GRAND_CHAOS_TIME))
			{
				final double chaosRate = 100 - ((npc.getCurrentHp() * 300) / npc.getMaxHp());
				changeTarget = ((chaosRate <= 10) && (Rnd.get(100) <= 10)) || ((chaosRate > 10) && (Rnd.get(100) <= chaosRate));
			}
			else if (chaostime > Config.MINION_CHAOS_TIME)
			{
				changeTarget = Rnd.get(100) <= (100 - ((npc.getCurrentHp() * 200) / npc.getMaxHp()));
			}
			
			if (changeTarget)
			{
				target = targetReconsider(true);
				if (target != null)
				{
					setTarget(target);
					chaostime = 0;
					return;
				}
			}
		}
		
		if (target == null)
		{
			target = targetReconsider(false);
			if (target == null)
			{
				return;
			}
			
			setTarget(target);
		}
		
		if (npc.hasSkillChance())
		{
			// First use the most important skill - heal. Even reconsider target.
			if (!npc.getTemplate().getAISkills(AISkillScope.HEAL).isEmpty())
			{
				final Skill healSkill = npc.getTemplate().getAISkills(AISkillScope.HEAL).get(Rnd.get(npc.getTemplate().getAISkills(AISkillScope.HEAL).size()));
				if (SkillCaster.checkUseConditions(npc, healSkill))
				{
					final L2Character healTarget = skillTargetReconsider(healSkill, false);
					if (healTarget != null)
					{
						final double healChance = (100 - healTarget.getCurrentHpPercent()) * 1.5; // Ensure heal chance is always 100% if HP is below 33%.
						if ((Rnd.get(100) < healChance) && checkSkillTarget(healSkill, healTarget))
						{
							setTarget(healTarget);
							npc.doCast(healSkill);
							LOGGER.finer(this + " used heal skill " + healSkill + " with target " + getTarget());
							return;
						}
					}
				}
			}
			
			// Then use the second most important skill - buff. Even reconsider target.
			if (!npc.getTemplate().getAISkills(AISkillScope.BUFF).isEmpty())
			{
				final Skill buffSkill = npc.getTemplate().getAISkills(AISkillScope.BUFF).get(Rnd.get(npc.getTemplate().getAISkills(AISkillScope.BUFF).size()));
				if (SkillCaster.checkUseConditions(npc, buffSkill))
				{
					final L2Character buffTarget = skillTargetReconsider(buffSkill, true);
					if (checkSkillTarget(buffSkill, buffTarget))
					{
						setTarget(buffTarget);
						npc.doCast(buffSkill);
						LOGGER.finer(this + " used buff skill " + buffSkill + " with target " + getTarget());
						return;
					}
				}
			}
			
			// Then try to immobolize target if moving.
			if (target.isMoving() && !npc.getTemplate().getAISkills(AISkillScope.IMMOBILIZE).isEmpty())
			{
				final Skill immobolizeSkill = npc.getTemplate().getAISkills(AISkillScope.IMMOBILIZE).get(Rnd.get(npc.getTemplate().getAISkills(AISkillScope.IMMOBILIZE).size()));
				if (SkillCaster.checkUseConditions(npc, immobolizeSkill) && checkSkillTarget(immobolizeSkill, target))
				{
					npc.doCast(immobolizeSkill);
					LOGGER.finer(this + " used immobolize skill " + immobolizeSkill + " with target " + getTarget());
					return;
				}
			}
			
			// Then try to mute target if he is casting.
			if (target.isCastingNow() && !npc.getTemplate().getAISkills(AISkillScope.COT).isEmpty())
			{
				final Skill muteSkill = npc.getTemplate().getAISkills(AISkillScope.COT).get(Rnd.get(npc.getTemplate().getAISkills(AISkillScope.COT).size()));
				if (SkillCaster.checkUseConditions(npc, muteSkill) && checkSkillTarget(muteSkill, target))
				{
					npc.doCast(muteSkill);
					LOGGER.finer(this + " used mute skill " + muteSkill + " with target " + getTarget());
					return;
				}
			}
			
			// Try cast short range skill.
			if (!npc.getShortRangeSkills().isEmpty())
			{
				final Skill shortRangeSkill = npc.getShortRangeSkills().get(Rnd.get(npc.getShortRangeSkills().size()));
				if (SkillCaster.checkUseConditions(npc, shortRangeSkill) && checkSkillTarget(shortRangeSkill, target))
				{
					npc.doCast(shortRangeSkill);
					LOGGER.finer(this + " used short range skill " + shortRangeSkill + " with target " + getTarget());
					return;
				}
			}
			
			// Try cast long range skill.
			if (!npc.getLongRangeSkills().isEmpty())
			{
				final Skill longRangeSkill = npc.getLongRangeSkills().get(Rnd.get(npc.getLongRangeSkills().size()));
				if (SkillCaster.checkUseConditions(npc, longRangeSkill) && checkSkillTarget(longRangeSkill, target))
				{
					npc.doCast(longRangeSkill);
					LOGGER.finer(this + " used long range skill " + longRangeSkill + " with target " + getTarget());
					return;
				}
			}
			
			// Finally, if none succeed, try to cast any skill.
			if (!npc.getTemplate().getAISkills(AISkillScope.GENERAL).isEmpty())
			{
				final Skill generalSkill = npc.getTemplate().getAISkills(AISkillScope.GENERAL).get(Rnd.get(npc.getTemplate().getAISkills(AISkillScope.GENERAL).size()));
				if (SkillCaster.checkUseConditions(npc, generalSkill) && checkSkillTarget(generalSkill, target))
				{
					npc.doCast(generalSkill);
					LOGGER.finer(this + " used general skill " + generalSkill + " with target " + getTarget());
					return;
				}
			}
		}
		
		// Check if target is within range or move.
		final int range = npc.getPhysicalAttackRange() + combinedCollision;
		if (npc.calculateDistance(target, false, false) > range)
		{
			if (checkTarget(target))
			{
				moveToPawn(target, range);
				return;
			}
			
			target = targetReconsider(false);
			if (target == null)
			{
				return;
			}
			
			setTarget(target);
		}
		
		// Attacks target
		_actor.doAttack(target);
	}
	
	private boolean checkSkillTarget(Skill skill, L2Object target)
	{
		if (target == null)
		{
			return false;
		}
		
		// Check if target is valid and within cast range.
		if (skill.getTarget(getActiveChar(), target, false, getActiveChar().isMovementDisabled(), false) == null)
		{
			return false;
		}
		
		if (target.isCharacter())
		{
			// Skip if target is already affected by such skill.
			if (skill.isContinuous())
			{
				final BuffInfo info = ((L2Character) target).getEffectList().getBuffInfoByAbnormalType(skill.getAbnormalType());
				if ((info != null) && (info.getSkill().getAbnormalLvl() >= skill.getAbnormalLvl()))
				{
					return false;
				}
			}
			
			// Check if target had buffs if skill is bad cancel, or debuffs if skill is good cancel.
			if (skill.hasEffectType(L2EffectType.DISPEL, L2EffectType.DISPEL_BY_SLOT))
			{
				if (skill.isBad())
				{
					if (!((L2Character) target).getEffectList().hasBuffs() && !((L2Character) target).getEffectList().hasDances())
					{
						return false;
					}
				}
				else if (!((L2Character) target).getEffectList().hasDebuffs())
				{
					return false;
				}
			}
			
			// Check for damaged targets if using healing skill.
			if ((((L2Character) target).getCurrentHp() == ((L2Character) target).getMaxHp()) && skill.hasEffectType(L2EffectType.HEAL))
			{
				return false;
			}
		}
		
		return true;
	}
	
	private boolean checkTarget(L2Object target)
	{
		if (target == null)
		{
			return false;
		}
		
		final L2Attackable npc = getActiveChar();
		if (target.isCharacter())
		{
			if (((L2Character) target).isDead())
			{
				return false;
			}
			
			if (npc.isMovementDisabled())
			{
				if (!npc.isInsideRadius(target, npc.getPhysicalAttackRange() + npc.getTemplate().getCollisionRadius() + ((L2Character) target).getTemplate().getCollisionRadius(), false, true))
				{
					return false;
				}
				
				if (!GeoData.getInstance().canSeeTarget(npc, target))
				{
					return false;
				}
			}
			
			if (!target.isAutoAttackable(npc))
			{
				return false;
			}
		}
		
		return GeoData.getInstance().canMove(npc, target);
	}
	
	private L2Character skillTargetReconsider(Skill skill, boolean insideCastRange)
	{
		// Check if skill can be casted.
		final L2Attackable npc = getActiveChar();
		if (!SkillCaster.checkUseConditions(npc, skill))
		{
			return null;
		}
		
		// Check current target first.
		final int range = insideCastRange ? skill.getCastRange() + getActiveChar().getTemplate().getCollisionRadius() : 2000; // TODO need some forget range
		
		Stream<L2Character> stream;
		if (skill.isBad())
		{
			//@formatter:off
			stream = npc.getAggroList().values().stream()
					.map(AggroInfo::getAttacker)
					.filter(c -> checkSkillTarget(skill, c))
					.sorted(Comparator.<L2Character>comparingInt(npc::getHating).reversed());
			//@formatter:on
		}
		else
		{
			stream = L2World.getInstance().getVisibleObjects(npc, L2Character.class, range, c -> checkSkillTarget(skill, c)).stream();
			
			// Maybe add self to the list of targets since getVisibleObjects doesn't return yourself.
			if (checkSkillTarget(skill, npc))
			{
				stream = Stream.concat(stream, Stream.of(npc));
			}
			
			// For heal skills sort by hp missing.
			if (skill.hasEffectType(L2EffectType.HEAL))
			{
				stream = stream.sorted(Comparator.comparingInt(L2Character::getCurrentHpPercent));
			}
		}
		
		// Return any target.
		return stream.findFirst().orElse(null);
		
	}
	
	private L2Character targetReconsider(boolean randomTarget)
	{
		final L2Attackable npc = getActiveChar();
		
		if (randomTarget)
		{
			Stream<L2Character> stream = npc.getAggroList().values().stream().map(AggroInfo::getAttacker).filter(this::checkTarget);
			
			// If npc is aggressive, add characters within aggro range too
			if (npc.isAggressive())
			{
				stream = Stream.concat(stream, L2World.getInstance().getVisibleObjects(npc, L2Character.class, npc.getAggroRange(), this::checkTarget).stream());
			}
			
			return stream.findAny().orElse(null);
		}
		
		//@formatter:off
		return npc.getAggroList().values().stream()
			.filter(a -> checkTarget(a.getAttacker()))
			.sorted(Comparator.comparingInt(AggroInfo::getHate))
			.map(AggroInfo::getAttacker)
			.findFirst()
			.orElse(npc.isAggressive() ? L2World.getInstance().getVisibleObjects(npc, L2Character.class, npc.getAggroRange(), this::checkTarget).stream().findAny().orElse(null) : null);
		//@formatter:on
	}
	
	/**
	 * Manage AI thinking actions of a L2Attackable.
	 */
	@Override
	protected void onEvtThink()
	{
		// Check if the actor can't use skills and if a thinking action isn't already in progress
		if (_thinking || getActiveChar().isAllSkillsDisabled())
		{
			return;
		}
		
		// Start thinking action
		_thinking = true;
		
		try
		{
			// Manage AI thinks of a L2Attackable
			switch (getIntention())
			{
				case AI_INTENTION_ACTIVE:
					thinkActive();
					break;
				case AI_INTENTION_ATTACK:
					thinkAttack();
					break;
				case AI_INTENTION_CAST:
					thinkCast();
					break;
			}
		}
		catch (Exception e)
		{
			LOGGER.log(Level.WARNING, this + " -  onEvtThink() failed", e);
		}
		finally
		{
			// Stop thinking action
			_thinking = false;
		}
	}
	
	/**
	 * Launch actions corresponding to the Event Attacked.<br>
	 * <B><U> Actions</U> :</B>
	 * <ul>
	 * <li>Init the attack : Calculate the attack timeout, Set the _globalAggro to 0, Add the attacker to the actor _aggroList</li>
	 * <li>Set the L2Character movement type to run and send Server->Client packet ChangeMoveType to all others L2PcInstance</li>
	 * <li>Set the Intention to AI_INTENTION_ATTACK</li>
	 * </ul>
	 * @param attacker The L2Character that attacks the actor
	 */
	@Override
	protected void onEvtAttacked(L2Character attacker)
	{
		final L2Attackable me = getActiveChar();
		final L2Object target = getTarget();
		// Calculate the attack timeout
		_attackTimeout = MAX_ATTACK_TIMEOUT + GameTimeController.getInstance().getGameTicks();
		
		// Set the _globalAggro to 0 to permit attack even just after spawn
		if (_globalAggro < 0)
		{
			_globalAggro = 0;
		}
		
		// Add the attacker to the _aggroList of the actor
		me.addDamageHate(attacker, 0, 1);
		
		// Set the L2Character movement type to run and send Server->Client packet ChangeMoveType to all others L2PcInstance
		if (!me.isRunning())
		{
			me.setRunning();
		}
		
		if (!getActiveChar().isCoreAIDisabled())
		{
			// Set the Intention to AI_INTENTION_ATTACK
			if (getIntention() != AI_INTENTION_ATTACK)
			{
				setIntention(CtrlIntention.AI_INTENTION_ATTACK, attacker);
			}
			else if (me.getMostHated() != target)
			{
				setIntention(CtrlIntention.AI_INTENTION_ATTACK, attacker);
			}
		}
		
		if (me.isMonster())
		{
			L2MonsterInstance master = (L2MonsterInstance) me;
			
			if (master.hasMinions())
			{
				master.getMinionList().onAssist(me, attacker);
			}
			
			master = master.getLeader();
			if ((master != null) && master.hasMinions())
			{
				master.getMinionList().onAssist(me, attacker);
			}
		}
		
		super.onEvtAttacked(attacker);
	}
	
	/**
	 * Launch actions corresponding to the Event Aggression.<br>
	 * <B><U> Actions</U> :</B>
	 * <ul>
	 * <li>Add the target to the actor _aggroList or update hate if already present</li>
	 * <li>Set the actor Intention to AI_INTENTION_ATTACK (if actor is L2GuardInstance check if it isn't too far from its home location)</li>
	 * </ul>
	 * @param aggro The value of hate to add to the actor against the target
	 */
	@Override
	protected void onEvtAggression(L2Character target, int aggro)
	{
		final L2Attackable me = getActiveChar();
		if (me.isDead())
		{
			return;
		}
		
		if (target != null)
		{
			// Add the target to the actor _aggroList or update hate if already present
			me.addDamageHate(target, 0, aggro);
			
			// Set the actor AI Intention to AI_INTENTION_ATTACK
			if (getIntention() != CtrlIntention.AI_INTENTION_ATTACK)
			{
				// Set the L2Character movement type to run and send Server->Client packet ChangeMoveType to all others L2PcInstance
				if (!me.isRunning())
				{
					me.setRunning();
				}
				
				setIntention(CtrlIntention.AI_INTENTION_ATTACK, target);
			}
			
			if (me.isMonster())
			{
				L2MonsterInstance master = (L2MonsterInstance) me;
				
				if (master.hasMinions())
				{
					master.getMinionList().onAssist(me, target);
				}
				
				master = master.getLeader();
				if ((master != null) && master.hasMinions())
				{
					master.getMinionList().onAssist(me, target);
				}
			}
		}
	}
	
	@Override
	protected void onIntentionActive()
	{
		// Cancel attack timeout
		_attackTimeout = Integer.MAX_VALUE;
		super.onIntentionActive();
	}
	
	public void setGlobalAggro(int value)
	{
		_globalAggro = value;
	}
	
	@Override
	public void setTarget(L2Object target)
	{
		// NPCs share their regular target with AI target.
		_actor.setTarget(target);
	}
	
	@Override
	public L2Object getTarget()
	{
		// NPCs share their regular target with AI target.
		return _actor.getTarget();
	}
	
	public L2Attackable getActiveChar()
	{
		return (L2Attackable) _actor;
	}
}