/** 
 * @file llloadingindicator.h
 * @brief Perpetual loading indicator
 *
 * $LicenseInfo:firstyear=2010&license=viewergpl$
 * 
 * Copyright (c) 2010, Linden Research, Inc.
 * 
 * Second Life Viewer Source Code
 * The source code in this file ("Source Code") is provided by Linden Lab
 * to you under the terms of the GNU General Public License, version 2.0
 * ("GPL"), unless you have obtained a separate licensing agreement
 * ("Other License"), formally executed by you and Linden Lab.  Terms of
 * the GPL can be found in doc/GPL-license.txt in this distribution, or
 * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
 * 
 * There are special exceptions to the terms and conditions of the GPL as
 * it is applied to this Source Code. View the full text of the exception
 * in the file doc/FLOSS-exception.txt in this software distribution, or
 * online at
 * http://secondlifegrid.net/programs/open_source/licensing/flossexception
 * 
 * By copying, modifying or distributing this software, you acknowledge
 * that you have read and understood your obligations described above,
 * and agree to abide by those obligations.
 * 
 * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
 * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
 * COMPLETENESS OR PERFORMANCE.
 * $/LicenseInfo$
 */

#ifndef LL_LLLOADINGINDICATOR_H
#define LL_LLLOADINGINDICATOR_H

#include "lluictrl.h"

///////////////////////////////////////////////////////////////////////////////
// class LLLoadingIndicator
///////////////////////////////////////////////////////////////////////////////

/**
 * Perpetual loading indicator (a la MacOSX or YouTube)
 * 
 * Number of rotations per second can be overriden
 * with the "roations_per_sec" parameter.
 * 
 * Can start/stop spinning.
 * 
 * @see start()
 * @see stop()
 */
class LLLoadingIndicator
: public LLUICtrl
{
	LOG_CLASS(LLLoadingIndicator);
public:
	struct Params : public LLInitParam::Block<Params, LLUICtrl::Params>
	{
		Optional<F32>	rotations_per_sec;
		Params()
		:	rotations_per_sec("rotations_per_sec", 1.0f)
		{}
	};

	virtual ~LLLoadingIndicator() {}

	// llview overrides
	virtual void draw();

	/**
	 * Stop spinning.
	 */
	void stop();

	/**
	 * Start spinning.
	 */
	void start();

private:
	LLLoadingIndicator(const Params&);
	friend class LLUICtrlFactory;

	class Data;

	F32						mRotationsPerSec;
	S8						mCurImageIdx;
	LLPointer<LLUIImage>	mCurImagep;
	LLFrameTimer			mImageSwitchTimer;
};

#endif // LL_LLLOADINGINDICATOR_H