/** 
 * @file llkeyframestandmotion.cpp
 * @brief Implementation of LLKeyframeStandMotion class.
 *
 * $LicenseInfo:firstyear=2001&license=viewergpl$
 * 
 * Copyright (c) 2001-2008, 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.
 * $/LicenseInfo$
 */

//-----------------------------------------------------------------------------
// Header Files
//-----------------------------------------------------------------------------
#include "linden_common.h"

#include "llkeyframestandmotion.h"
#include "llcharacter.h"

//-----------------------------------------------------------------------------
// Macros and consts
//-----------------------------------------------------------------------------
#define GO_TO_KEY_POSE	1
#define MIN_TRACK_SPEED 0.01f
const F32 ROTATION_THRESHOLD = 0.6f;
const F32 POSITION_THRESHOLD = 0.1f;

//-----------------------------------------------------------------------------
// LLKeyframeStandMotion()
// Class Constructor
//-----------------------------------------------------------------------------
LLKeyframeStandMotion::LLKeyframeStandMotion(const LLUUID &id) : LLKeyframeMotion(id)
{
	mFlipFeet = FALSE;
	mCharacter = NULL;

	// create kinematic hierarchy
	mPelvisJoint.addChild( &mHipLeftJoint );
		mHipLeftJoint.addChild( &mKneeLeftJoint );
			mKneeLeftJoint.addChild( &mAnkleLeftJoint );
	mPelvisJoint.addChild( &mHipRightJoint );
		mHipRightJoint.addChild( &mKneeRightJoint );
			mKneeRightJoint.addChild( &mAnkleRightJoint );

	mPelvisState = NULL;

	mHipLeftState =  NULL;
	mKneeLeftState =  NULL;
	mAnkleLeftState =  NULL;

	mHipRightState =  NULL;
	mKneeRightState =  NULL;
	mAnkleRightState =  NULL;

	mTrackAnkles = TRUE;

	mFrameNum = 0;
}


//-----------------------------------------------------------------------------
// ~LLKeyframeStandMotion()
// Class Destructor
//-----------------------------------------------------------------------------
LLKeyframeStandMotion::~LLKeyframeStandMotion()
{
}


//-----------------------------------------------------------------------------
// LLKeyframeStandMotion::onInitialize()
//-----------------------------------------------------------------------------
LLMotion::LLMotionInitStatus LLKeyframeStandMotion::onInitialize(LLCharacter *character)
{
	// save character pointer for later use
	mCharacter = character;

	mFlipFeet = FALSE;

	// load keyframe data, setup pose and joint states
	LLMotion::LLMotionInitStatus status = LLKeyframeMotion::onInitialize(character);
	if ( status == STATUS_FAILURE )
	{
		return status;
	}

	// find the necessary joint states
	LLPose *pose = getPose();
	mPelvisState = pose->findJointState("mPelvis");
	
	mHipLeftState = pose->findJointState("mHipLeft");
	mKneeLeftState = pose->findJointState("mKneeLeft");
	mAnkleLeftState = pose->findJointState("mAnkleLeft");

	mHipRightState = pose->findJointState("mHipRight");
	mKneeRightState = pose->findJointState("mKneeRight");
	mAnkleRightState = pose->findJointState("mAnkleRight");

	if (	!mPelvisState ||
			!mHipLeftState ||
			!mKneeLeftState ||
			!mAnkleLeftState ||
			!mHipRightState ||
			!mKneeRightState ||
			!mAnkleRightState )
	{
		llinfos << getName() << ": Can't find necessary joint states" << llendl;
		return STATUS_FAILURE;
	}

	return STATUS_SUCCESS;
}

//-----------------------------------------------------------------------------
// LLKeyframeStandMotion::onActivate()
//-----------------------------------------------------------------------------
BOOL LLKeyframeStandMotion::onActivate()
{
	//-------------------------------------------------------------------------
	// setup the IK solvers
	//-------------------------------------------------------------------------
	mIKLeft.setPoleVector( LLVector3(1.0f, 0.0f, 0.0f));
	mIKRight.setPoleVector( LLVector3(1.0f, 0.0f, 0.0f));
	mIKLeft.setBAxis( LLVector3(0.05f, 1.0f, 0.0f));
	mIKRight.setBAxis( LLVector3(-0.05f, 1.0f, 0.0f));

	mLastGoodPelvisRotation.loadIdentity();
	mLastGoodPosition.clearVec();

	mFrameNum = 0;

	return LLKeyframeMotion::onActivate();
}

//-----------------------------------------------------------------------------
// LLKeyframeStandMotion::onDeactivate()
//-----------------------------------------------------------------------------
void LLKeyframeStandMotion::onDeactivate()
{
	LLKeyframeMotion::onDeactivate();
}

//-----------------------------------------------------------------------------
// LLKeyframeStandMotion::onUpdate()
//-----------------------------------------------------------------------------
BOOL LLKeyframeStandMotion::onUpdate(F32 time, U8* joint_mask)
{
	//-------------------------------------------------------------------------
	// let the base class update the cycle
	//-------------------------------------------------------------------------
	BOOL status = LLKeyframeMotion::onUpdate(time, joint_mask);
	if (!status)
	{
		return FALSE;
	}

	LLVector3 root_world_pos = mPelvisState->getJoint()->getParent()->getWorldPosition();

	// have we received a valid world position for this avatar?
	if (root_world_pos.isExactlyZero())
	{
		return TRUE;
	}

	//-------------------------------------------------------------------------
	// Stop tracking (start locking) ankles once ease in is done.
	// Setting this here ensures we track until we get valid foot position.
	//-------------------------------------------------------------------------
	if (dot(mPelvisState->getJoint()->getWorldRotation(), mLastGoodPelvisRotation) < ROTATION_THRESHOLD)
	{
		mLastGoodPelvisRotation = mPelvisState->getJoint()->getWorldRotation();
		mLastGoodPelvisRotation.normQuat();
		mTrackAnkles = TRUE;
	}
	else if ((mCharacter->getCharacterPosition() - mLastGoodPosition).magVecSquared() > POSITION_THRESHOLD)
	{
		mLastGoodPosition = mCharacter->getCharacterPosition();
		mTrackAnkles = TRUE;
	}
	else if (mPose.getWeight() < 1.f)
	{
		mTrackAnkles = TRUE;
	}


	//-------------------------------------------------------------------------
	// propagate joint positions to internal versions
	//-------------------------------------------------------------------------
	mPelvisJoint.setPosition(
			root_world_pos +
			mPelvisState->getPosition() );

	mHipLeftJoint.setPosition( mHipLeftState->getJoint()->getPosition() );
	mKneeLeftJoint.setPosition( mKneeLeftState->getJoint()->getPosition() );
	mAnkleLeftJoint.setPosition( mAnkleLeftState->getJoint()->getPosition() );

	mHipLeftJoint.setScale( mHipLeftState->getJoint()->getScale() );
	mKneeLeftJoint.setScale( mKneeLeftState->getJoint()->getScale() );
	mAnkleLeftJoint.setScale( mAnkleLeftState->getJoint()->getScale() );

	mHipRightJoint.setPosition( mHipRightState->getJoint()->getPosition() );
	mKneeRightJoint.setPosition( mKneeRightState->getJoint()->getPosition() );
	mAnkleRightJoint.setPosition( mAnkleRightState->getJoint()->getPosition() );

	mHipRightJoint.setScale( mHipRightState->getJoint()->getScale() );
	mKneeRightJoint.setScale( mKneeRightState->getJoint()->getScale() );
	mAnkleRightJoint.setScale( mAnkleRightState->getJoint()->getScale() );
	//-------------------------------------------------------------------------
	// propagate joint rotations to internal versions
	//-------------------------------------------------------------------------
	mPelvisJoint.setRotation( mPelvisState->getJoint()->getWorldRotation() );

#if GO_TO_KEY_POSE
	mHipLeftJoint.setRotation( mHipLeftState->getRotation() );
	mKneeLeftJoint.setRotation( mKneeLeftState->getRotation() );
	mAnkleLeftJoint.setRotation( mAnkleLeftState->getRotation() );

	mHipRightJoint.setRotation( mHipRightState->getRotation() );
	mKneeRightJoint.setRotation( mKneeRightState->getRotation() );
	mAnkleRightJoint.setRotation( mAnkleRightState->getRotation() );
#else
	mHipLeftJoint.setRotation( mHipLeftState->getJoint()->getRotation() );
	mKneeLeftJoint.setRotation( mKneeLeftState->getJoint()->getRotation() );
	mAnkleLeftJoint.setRotation( mAnkleLeftState->getJoint()->getRotation() );

	mHipRightJoint.setRotation( mHipRightState->getJoint()->getRotation() );
	mKneeRightJoint.setRotation( mKneeRightState->getJoint()->getRotation() );
	mAnkleRightJoint.setRotation( mAnkleRightState->getJoint()->getRotation() );
#endif

	// need to wait for underlying keyframe motion to affect the skeleton
	if (mFrameNum == 2)
	{
		mIKLeft.setupJoints( &mHipLeftJoint, &mKneeLeftJoint, &mAnkleLeftJoint, &mTargetLeft );
		mIKRight.setupJoints( &mHipRightJoint, &mKneeRightJoint, &mAnkleRightJoint, &mTargetRight );
	}
	else if (mFrameNum < 2)
	{
		mFrameNum++;
		return TRUE;
	}

	mFrameNum++;

	//-------------------------------------------------------------------------
	// compute target position by projecting ankles to the ground
	//-------------------------------------------------------------------------
	if ( mTrackAnkles )
	{
		mCharacter->getGround( mAnkleLeftJoint.getWorldPosition(), mPositionLeft, mNormalLeft);
		mCharacter->getGround( mAnkleRightJoint.getWorldPosition(), mPositionRight, mNormalRight);

		mTargetLeft.setPosition( mPositionLeft );
		mTargetRight.setPosition( mPositionRight );
	}

	//-------------------------------------------------------------------------
	// update solvers
	//-------------------------------------------------------------------------
	mIKLeft.solve();
	mIKRight.solve();

	//-------------------------------------------------------------------------
	// make ankle rotation conform to the ground
	//-------------------------------------------------------------------------
	if ( mTrackAnkles )
	{
		LLVector4 dirLeft4 = mAnkleLeftJoint.getWorldMatrix().getFwdRow4();
		LLVector4 dirRight4 = mAnkleRightJoint.getWorldMatrix().getFwdRow4();
		LLVector3 dirLeft = vec4to3( dirLeft4 );
		LLVector3 dirRight = vec4to3( dirRight4 );

		LLVector3 up;
		LLVector3 dir;
		LLVector3 left;

		up = mNormalLeft;
		up.normVec();
		if (mFlipFeet)
		{
			up *= -1.0f;
		}
		dir = dirLeft;
		dir.normVec();
		left = up % dir;
		left.normVec();
		dir = left % up;
		mRotationLeft = LLQuaternion( dir, left, up );

		up = mNormalRight;
		up.normVec();
		if (mFlipFeet)
		{
			up *= -1.0f;
		}
		dir = dirRight;
		dir.normVec();
		left = up % dir;
		left.normVec();
		dir = left % up;
		mRotationRight = LLQuaternion( dir, left, up );
	}
	mAnkleLeftJoint.setWorldRotation( mRotationLeft );
	mAnkleRightJoint.setWorldRotation( mRotationRight );

	//-------------------------------------------------------------------------
	// propagate joint rotations to joint states
	//-------------------------------------------------------------------------
	mHipLeftState->setRotation( mHipLeftJoint.getRotation() );
	mKneeLeftState->setRotation( mKneeLeftJoint.getRotation() );
	mAnkleLeftState->setRotation( mAnkleLeftJoint.getRotation() );

	mHipRightState->setRotation( mHipRightJoint.getRotation() );
	mKneeRightState->setRotation( mKneeRightJoint.getRotation() );
	mAnkleRightState->setRotation( mAnkleRightJoint.getRotation() );

	//llinfos << "Stand drift amount " << (mCharacter->getCharacterPosition() - mLastGoodPosition).magVec() << llendl;

//	llinfos << "DEBUG: " << speed << " : " << mTrackAnkles << llendl;
	return TRUE;
}

// End