/*
 * 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_ATTACK;
import static com.l2jmobius.gameserver.ai.CtrlIntention.AI_INTENTION_FOLLOW;
import static com.l2jmobius.gameserver.ai.CtrlIntention.AI_INTENTION_IDLE;

import java.util.concurrent.Future;

import com.l2jmobius.commons.util.Rnd;
import com.l2jmobius.gameserver.GeoData;
import com.l2jmobius.gameserver.ThreadPoolManager;
import com.l2jmobius.gameserver.model.L2Object;
import com.l2jmobius.gameserver.model.actor.L2Character;
import com.l2jmobius.gameserver.model.actor.L2Summon;
import com.l2jmobius.gameserver.model.items.instance.L2ItemInstance;
import com.l2jmobius.gameserver.model.skills.Skill;
import com.l2jmobius.gameserver.model.skills.SkillCaster;

public class L2SummonAI extends L2PlayableAI implements Runnable
{
	private static final int AVOID_RADIUS = 70;
	
	private volatile boolean _thinking; // to prevent recursive thinking
	private volatile boolean _startFollow = ((L2Summon) _actor).getFollowStatus();
	private L2Character _lastAttack = null;
	
	private volatile boolean _startAvoid;
	private volatile boolean _isDefending;
	private Future<?> _avoidTask = null;
	
	public L2SummonAI(L2Summon summon)
	{
		super(summon);
	}
	
	@Override
	protected void onIntentionIdle()
	{
		stopFollow();
		_startFollow = false;
		onIntentionActive();
	}
	
	@Override
	protected void onIntentionActive()
	{
		final L2Summon summon = (L2Summon) _actor;
		if (_startFollow)
		{
			setIntention(AI_INTENTION_FOLLOW, summon.getOwner());
		}
		else
		{
			super.onIntentionActive();
		}
	}
	
	@Override
	synchronized void changeIntention(CtrlIntention intention, Object... args)
	{
		switch (intention)
		{
			case AI_INTENTION_ACTIVE:
			case AI_INTENTION_FOLLOW:
			{
				startAvoidTask();
				break;
			}
			default:
			{
				stopAvoidTask();
			}
		}
		
		super.changeIntention(intention, args);
	}
	
	private void thinkAttack()
	{
		final L2Object target = getTarget();
		final L2Character attackTarget = (target != null) && target.isCharacter() ? (L2Character) target : null;
		
		if (checkTargetLostOrDead(attackTarget))
		{
			setTarget(null);
			return;
		}
		if (maybeMoveToPawn(attackTarget, _actor.getPhysicalAttackRange()))
		{
			return;
		}
		clientStopMoving(null);
		_actor.doAttack(attackTarget);
	}
	
	private void thinkCast()
	{
		final L2Summon summon = (L2Summon) _actor;
		if (summon.isCastingNow(SkillCaster::isAnyNormalType))
		{
			return;
		}
		
		final L2Object target = _skill.getTarget(_actor, _forceUse, _dontMove, false);
		if (checkTargetLost(target))
		{
			setTarget(null);
			return;
		}
		final boolean val = _startFollow;
		if (maybeMoveToPawn(target, _actor.getMagicalAttackRange(_skill)))
		{
			return;
		}
		summon.setFollowStatus(false);
		setIntention(AI_INTENTION_IDLE);
		_startFollow = val;
		_actor.doCast(_skill, _item, _forceUse, _dontMove);
	}
	
	private void thinkPickUp()
	{
		final L2Object target = getTarget();
		if (checkTargetLost(target))
		{
			return;
		}
		if (maybeMoveToPawn(target, 36))
		{
			return;
		}
		setIntention(AI_INTENTION_IDLE);
		getActor().doPickupItem(target);
	}
	
	private void thinkInteract()
	{
		final L2Object target = getTarget();
		if (checkTargetLost(target))
		{
			return;
		}
		if (maybeMoveToPawn(target, 36))
		{
			return;
		}
		setIntention(AI_INTENTION_IDLE);
	}
	
	@Override
	protected void onEvtThink()
	{
		if (_thinking || _actor.isCastingNow() || _actor.isAllSkillsDisabled())
		{
			return;
		}
		_thinking = true;
		try
		{
			switch (getIntention())
			{
				case AI_INTENTION_ATTACK:
				{
					thinkAttack();
					break;
				}
				case AI_INTENTION_CAST:
				{
					thinkCast();
					break;
				}
				case AI_INTENTION_PICK_UP:
				{
					thinkPickUp();
					break;
				}
				case AI_INTENTION_INTERACT:
				{
					thinkInteract();
					break;
				}
			}
		}
		finally
		{
			_thinking = false;
		}
	}
	
	@Override
	protected void onEvtFinishCasting()
	{
		if (_lastAttack == null)
		{
			((L2Summon) _actor).setFollowStatus(_startFollow);
		}
		else
		{
			setIntention(CtrlIntention.AI_INTENTION_ATTACK, _lastAttack);
			_lastAttack = null;
		}
	}
	
	@Override
	protected void onEvtAttacked(L2Character attacker)
	{
		super.onEvtAttacked(attacker);
		
		if (isDefending())
		{
			defendAttack(attacker);
		}
		else
		{
			avoidAttack(attacker);
		}
	}
	
	@Override
	protected void onEvtEvaded(L2Character attacker)
	{
		super.onEvtEvaded(attacker);
		
		if (isDefending())
		{
			defendAttack(attacker);
		}
		else
		{
			avoidAttack(attacker);
		}
	}
	
	private void avoidAttack(L2Character attacker)
	{
		// Don't move while casting. It breaks casting animation, but still casts the skill... looks so bugged.
		if (_actor.isCastingNow())
		{
			return;
		}
		
		final L2Character owner = getActor().getOwner();
		// trying to avoid if summon near owner
		if ((owner != null) && (owner != attacker) && owner.isInsideRadius(_actor, 2 * AVOID_RADIUS, true, false))
		{
			_startAvoid = true;
		}
	}
	
	public void defendAttack(L2Character attacker)
	{
		// Cannot defend while attacking or casting.
		if (_actor.isAttackingNow() || _actor.isCastingNow())
		{
			return;
		}
		
		final L2Summon summon = getActor();
		if ((summon.getOwner() != null) && (summon.getOwner() != attacker) && !summon.isMoving() && summon.canAttack(attacker, false) && summon.getOwner().isInsideRadius(_actor, 2 * AVOID_RADIUS, true, false))
		{
			summon.doAttack(attacker);
		}
	}
	
	@Override
	public void run()
	{
		if (_startAvoid)
		{
			_startAvoid = false;
			
			if (!_clientMoving && !_actor.isDead() && !_actor.isMovementDisabled() && (_actor.getMoveSpeed() > 0))
			{
				final int ownerX = ((L2Summon) _actor).getOwner().getX();
				final int ownerY = ((L2Summon) _actor).getOwner().getY();
				final double angle = Math.toRadians(Rnd.get(-90, 90)) + Math.atan2(ownerY - _actor.getY(), ownerX - _actor.getX());
				
				final int targetX = ownerX + (int) (AVOID_RADIUS * Math.cos(angle));
				final int targetY = ownerY + (int) (AVOID_RADIUS * Math.sin(angle));
				if (GeoData.getInstance().canMove(_actor, targetX, targetY, _actor.getZ()))
				{
					moveTo(targetX, targetY, _actor.getZ());
				}
			}
		}
	}
	
	public void notifyFollowStatusChange()
	{
		_startFollow = !_startFollow;
		switch (getIntention())
		{
			case AI_INTENTION_ACTIVE:
			case AI_INTENTION_FOLLOW:
			case AI_INTENTION_IDLE:
			case AI_INTENTION_MOVE_TO:
			case AI_INTENTION_PICK_UP:
			{
				((L2Summon) _actor).setFollowStatus(_startFollow);
			}
		}
	}
	
	public void setStartFollowController(boolean val)
	{
		_startFollow = val;
	}
	
	@Override
	protected void onIntentionCast(Skill skill, L2Object target, L2ItemInstance item, boolean forceUse, boolean dontMove)
	{
		if (getIntention() == AI_INTENTION_ATTACK)
		{
			_lastAttack = (getTarget() != null) && getTarget().isCharacter() ? (L2Character) getTarget() : null;
		}
		else
		{
			_lastAttack = null;
		}
		super.onIntentionCast(skill, target, item, forceUse, dontMove);
	}
	
	private void startAvoidTask()
	{
		if (_avoidTask == null)
		{
			_avoidTask = ThreadPoolManager.getInstance().scheduleAiAtFixedRate(this, 100, 100);
		}
	}
	
	private void stopAvoidTask()
	{
		if (_avoidTask != null)
		{
			_avoidTask.cancel(false);
			_avoidTask = null;
		}
	}
	
	@Override
	public void stopAITask()
	{
		stopAvoidTask();
		super.stopAITask();
	}
	
	@Override
	public L2Summon getActor()
	{
		return (L2Summon) super.getActor();
	}
	
	/**
	 * @return if the summon is defending itself or master.
	 */
	public boolean isDefending()
	{
		return _isDefending;
	}
	
	/**
	 * @param isDefending set the summon to defend itself and master, or be passive and avoid while being attacked.
	 */
	public void setDefending(boolean isDefending)
	{
		_isDefending = isDefending;
	}
}