/** 
 * @file llhudeffectlookat.h
 * @brief LLHUDEffectLookAt class definition
 *
 * $LicenseInfo:firstyear=2002&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#ifndef LL_LLHUDEFFECTLOOKAT_H
#define LL_LLHUDEFFECTLOOKAT_H

#include "llhudeffect.h"

class LLViewerObject;
class LLVOAvatar;
class LLAttentionSet;

typedef enum e_lookat_type
{
	LOOKAT_TARGET_NONE,
	LOOKAT_TARGET_IDLE,
	LOOKAT_TARGET_AUTO_LISTEN,
	LOOKAT_TARGET_FREELOOK,
	LOOKAT_TARGET_RESPOND,
	LOOKAT_TARGET_HOVER,
	LOOKAT_TARGET_CONVERSATION,
	LOOKAT_TARGET_SELECT,
	LOOKAT_TARGET_FOCUS,
	LOOKAT_TARGET_MOUSELOOK,
	LOOKAT_TARGET_CLEAR,
	LOOKAT_NUM_TARGETS
} ELookAtType;

class LLHUDEffectLookAt final : public LLHUDEffect
{
public:
	friend class LLHUDObject;

	/*virtual*/ void markDead() override;
	/*virtual*/ void setSourceObject(LLViewerObject* objectp) override;

	BOOL setLookAt(ELookAtType target_type, LLViewerObject *object, LLVector3 position);
	void clearLookAtTarget();

	ELookAtType getLookAtType() const { return mTargetType; }
	const LLVector3& getTargetPos() const { return mTargetPos; }
	const LLVector3d& getTargetOffset() const { return mTargetOffsetGlobal; }
	bool calcTargetPosition();

protected:
	LLHUDEffectLookAt(const U8 type);
	~LLHUDEffectLookAt();

	/*virtual*/ void update() override;
	/*virtual*/ void render() override;
	/*virtual*/ void packData(LLMessageSystem *mesgsys) override;
	/*virtual*/ void unpackData(LLMessageSystem *mesgsys, S32 blocknum) override;
	
	// lookat behavior has either target position or target object with offset
	void setTargetObjectAndOffset(LLViewerObject *objp, LLVector3d offset);
	void setTargetPosGlobal(const LLVector3d &target_pos_global);

public:
	static BOOL sDebugLookAt;

private:
	ELookAtType					mTargetType;
	LLVector3d					mTargetOffsetGlobal;
	LLVector3					mLastSentOffsetGlobal;
	F32							mKillTime;
	LLFrameTimer				mTimer;
	LLVector3					mTargetPos;
	F32							mLastSendTime;
	LLAttentionSet*				mAttentions;
};

#endif // LL_LLHUDEFFECTLOOKAT_H
