/**
 * @file lldriverparam.cpp
 * @brief A visual parameter that drives (controls) other visual parameters.
 *
 * $LicenseInfo:firstyear=2002&license=viewerlgpl$
 * 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
 * $/LicenseInfo$
 */

#include "linden_common.h"

#include "lldriverparam.h"

#include "llavatarappearance.h"
#include "llwearable.h"
#include "llwearabledata.h"

//-----------------------------------------------------------------------------
// LLDriverParamInfo
//-----------------------------------------------------------------------------

LLDriverParamInfo::LLDriverParamInfo() :
    mDriverParam(NULL)
{
}

bool LLDriverParamInfo::parseXml(LLXmlTreeNode* node)
{
    llassert( node->hasName( "param" ) && node->getChildByName( "param_driver" ) );

    if( !LLViewerVisualParamInfo::parseXml( node ))
        return false;

    LLXmlTreeNode* param_driver_node = node->getChildByName( "param_driver" );
    if( !param_driver_node )
        return false;

    for (LLXmlTreeNode* child = param_driver_node->getChildByName( "driven" );
         child;
         child = param_driver_node->getNextNamedChild())
    {
        S32 driven_id;
        static LLStdStringHandle id_string = LLXmlTree::addAttributeString("id");
        if( child->getFastAttributeS32( id_string, driven_id ) )
        {
            F32 min1 = mMinWeight;
            F32 max1 = mMaxWeight;
            F32 max2 = max1;
            F32 min2 = max1;

            //  driven    ________                          //
            //  ^        /|       |\                        //
            //  |       / |       | \                       //
            //  |      /  |       |  \                      //
            //  |     /   |       |   \                     //
            //  |    /    |       |    \                    //
            //-------|----|-------|----|-------> driver     //
            //  | min1   max1    max2  min2

            static LLStdStringHandle min1_string = LLXmlTree::addAttributeString("min1");
            child->getFastAttributeF32( min1_string, min1 ); // optional
            static LLStdStringHandle max1_string = LLXmlTree::addAttributeString("max1");
            child->getFastAttributeF32( max1_string, max1 ); // optional
            static LLStdStringHandle max2_string = LLXmlTree::addAttributeString("max2");
            child->getFastAttributeF32( max2_string, max2 ); // optional
            static LLStdStringHandle min2_string = LLXmlTree::addAttributeString("min2");
            child->getFastAttributeF32( min2_string, min2 ); // optional

            // Push these on the front of the deque, so that we can construct
            // them in order later (faster)
            mDrivenInfoList.push_front( LLDrivenEntryInfo( driven_id, min1, max1, max2, min2 ) );
        }
        else
        {
            LL_ERRS() << "<driven> Unable to resolve driven parameter: " << driven_id << LL_ENDL;
            return false;
        }
    }
    return true;
}

//virtual
void LLDriverParamInfo::toStream(std::ostream &out)
{
    LLViewerVisualParamInfo::toStream(out);
    out << "driver" << "\t";
    out << mDrivenInfoList.size() << "\t";
    for (LLDrivenEntryInfo& driven : mDrivenInfoList)
    {
        out << driven.mDrivenID << "\t";
    }

    out << std::endl;

    // FIXME - this mDriverParam backlink makes no sense, because the
    // LLDriverParamInfos are static objects - there's only one copy
    // for each param type, so the backlink will just reference the
    // corresponding param in the most recently created
    // avatar. Apparently these toStream() methods are not currently
    // used anywhere, so it's not an urgent problem.
    LL_WARNS_ONCE() << "Invalid usage of mDriverParam." << LL_ENDL;

    if(mDriverParam && mDriverParam->getAvatarAppearance()->isSelf() &&
        mDriverParam->getAvatarAppearance()->isValid())
    {
        for (LLDrivenEntryInfo& driven : mDrivenInfoList)
        {
            LLViewerVisualParam *param =
                (LLViewerVisualParam*)mDriverParam->getAvatarAppearance()->getVisualParam(driven.mDrivenID);
            if (param)
            {
                param->getInfo()->toStream(out);
                if (param->getWearableType() != mWearableType)
                {
                    if(param->getCrossWearable())
                    {
                        out << "cross-wearable" << "\t";
                    }
                    else
                    {
                        out << "ERROR!" << "\t";
                    }
                }
                else
                {
                    out << "valid" << "\t";
                }
            }
            else
            {
                LL_WARNS() << "could not get parameter " << driven.mDrivenID << " from avatar "
                        << mDriverParam->getAvatarAppearance()
                        << " for driver parameter " << getID() << LL_ENDL;
            }
            out << std::endl;
        }
    }
}

//-----------------------------------------------------------------------------
// LLDriverParam
//-----------------------------------------------------------------------------

LLDriverParam::LLDriverParam(LLAvatarAppearance *appearance, LLWearable* wearable /* = NULL */)
    : LLViewerVisualParam(),
    mDefaultVec(),
    mDriven(),
    mCurrentDistortionParam( NULL ),
    mAvatarAppearance(appearance),
    mWearablep(wearable)
{
    llassert(mAvatarAppearance);
    llassert((mWearablep == NULL) || mAvatarAppearance->isSelf());
    mDefaultVec.clear();
}

LLDriverParam::LLDriverParam(const LLDriverParam& pOther)
    : LLViewerVisualParam(pOther),
    mDefaultVec(pOther.mDefaultVec),
    mDriven(pOther.mDriven),
    mCurrentDistortionParam(pOther.mCurrentDistortionParam),
    mAvatarAppearance(pOther.mAvatarAppearance),
    mWearablep(pOther.mWearablep)
{
    llassert(mAvatarAppearance);
    llassert((mWearablep == NULL) || mAvatarAppearance->isSelf());
}

LLDriverParam::~LLDriverParam()
{
}

bool LLDriverParam::setInfo(LLDriverParamInfo *info)
{
    llassert(mInfo == NULL);
    if (info->mID < 0)
        return false;
    mInfo = info;
    mID = info->mID;
    info->mDriverParam = this;

    setWeight(getDefaultWeight());

    return true;
}

/*virtual*/ LLViewerVisualParam* LLDriverParam::cloneParam(LLWearable* wearable) const
{
    llassert(wearable);
    return new LLDriverParam(*this);
}

void LLDriverParam::setWeight(F32 weight)
{
    F32 min_weight = getMinWeight();
    F32 max_weight = getMaxWeight();
    if (mIsAnimating)
    {
        // allow overshoot when animating
        mCurWeight = weight;
    }
    else
    {
        mCurWeight = llclamp(weight, min_weight, max_weight);
    }

    //  driven    ________
    //  ^        /|       |\       ^
    //  |       / |       | \      |
    //  |      /  |       |  \     |
    //  |     /   |       |   \    |
    //  |    /    |       |    \   |
    //-------|----|-------|----|-------> driver
    //  | min1   max1    max2  min2

    for(LLDrivenEntry& driven : mDriven)
    {
        LLDrivenEntry* drivenp = &driven;
        LLDrivenEntryInfo* info = drivenp->mInfo;

        F32 driven_weight = 0.f;
        F32 driven_min = drivenp->mParam->getMinWeight();
        F32 driven_max = drivenp->mParam->getMaxWeight();

        if (mIsAnimating)
        {
            // driven param doesn't interpolate (textures, for example)
            if (!drivenp->mParam->getAnimating())
            {
                continue;
            }
            if( mCurWeight < info->mMin1 )
            {
                if (info->mMin1 == min_weight)
                {
                    if (info->mMin1 == info->mMax1)
                    {
                        driven_weight = driven_max;
                    }
                    else
                    {
                        //up slope extrapolation
                        F32 t = (mCurWeight - info->mMin1) / (info->mMax1 - info->mMin1 );
                        driven_weight = driven_min + t * (driven_max - driven_min);
                    }
                }
                else
                {
                    driven_weight = driven_min;
                }

                setDrivenWeight(drivenp,driven_weight);
                continue;
            }
            else
            if ( mCurWeight > info->mMin2 )
            {
                if (info->mMin2 == max_weight)
                {
                    if (info->mMin2 == info->mMax2)
                    {
                        driven_weight = driven_max;
                    }
                    else
                    {
                        //down slope extrapolation
                        F32 t = (mCurWeight - info->mMax2) / (info->mMin2 - info->mMax2 );
                        driven_weight = driven_max + t * (driven_min - driven_max);
                    }
                }
                else
                {
                    driven_weight = driven_min;
                }

                setDrivenWeight(drivenp,driven_weight);
                continue;
            }
        }

        driven_weight = getDrivenWeight(drivenp, mCurWeight);
        setDrivenWeight(drivenp,driven_weight);
    }
}

F32 LLDriverParam::getTotalDistortion()
{
    F32 sum = 0.f;
    for(LLDrivenEntry& driven : mDriven)
    {
        sum += driven.mParam->getTotalDistortion();
    }

    return sum;
}

const LLVector4a    &LLDriverParam::getAvgDistortion()
{
    // It's not actually correct to take the average of averages, but it good enough here.
    LLVector4a sum;
    sum.clear();
    S32 count = 0;
    for(LLDrivenEntry& driven : mDriven)
    {
        sum.add(driven.mParam->getAvgDistortion());
        count++;
    }
    sum.mul( 1.f/(F32)count);

    mDefaultVec = sum;
    return mDefaultVec;
}

F32 LLDriverParam::getMaxDistortion()
{
    F32 max = 0.f;
    for(LLDrivenEntry& driven : mDriven)
    {
        F32 param_max = driven.mParam->getMaxDistortion();
        if( param_max > max )
        {
            max = param_max;
        }
    }

    return max;
}


LLVector4a  LLDriverParam::getVertexDistortion(S32 index, LLPolyMesh *poly_mesh)
{
    LLVector4a sum;
    sum.clear();
    for(LLDrivenEntry& driven : mDriven)
    {
        sum.add(driven.mParam->getVertexDistortion(index, poly_mesh));
    }
    return sum;
}

const LLVector4a*   LLDriverParam::getFirstDistortion(U32 *index, LLPolyMesh **poly_mesh)
{
    mCurrentDistortionParam = NULL;
    const LLVector4a* v = NULL;
    for(LLDrivenEntry& driven : mDriven)
    {
        v = driven.mParam->getFirstDistortion(index, poly_mesh);
        if( v )
        {
            mCurrentDistortionParam = driven.mParam;
            break;
        }
    }

    return v;
};

const LLVector4a*   LLDriverParam::getNextDistortion(U32 *index, LLPolyMesh **poly_mesh)
{
    llassert( mCurrentDistortionParam );
    if( !mCurrentDistortionParam )
    {
        return NULL;
    }

    LLDrivenEntry* driven = NULL;
    entry_list_t::iterator iter;

    // Set mDriven iteration to the right point
    for( iter = mDriven.begin(); iter != mDriven.end(); iter++ )
    {
        driven = &(*iter);
        if( driven->mParam == mCurrentDistortionParam )
        {
            break;
        }
    }

    llassert(driven);
    if (!driven)
    {
        return NULL; // shouldn't happen, but...
    }

    // We're already in the middle of a param's distortions, so get the next one.
    const LLVector4a* v = driven->mParam->getNextDistortion( index, poly_mesh );
    if( (!v) && (iter != mDriven.end()) )
    {
        // This param is finished, so start the next param.  It might not have any
        // distortions, though, so we have to loop to find the next param that does.
        for( iter++; iter != mDriven.end(); iter++ )
        {
            driven = &(*iter);
            v = driven->mParam->getFirstDistortion(index, poly_mesh);
            if( v )
            {
                mCurrentDistortionParam = driven->mParam;
                break;
            }
        }
    }

    return v;
};

S32 LLDriverParam::getDrivenParamsCount() const
{
    return static_cast<S32>(mDriven.size());
}

const LLViewerVisualParam* LLDriverParam::getDrivenParam(S32 index) const
{
    if (0 > index || index >= mDriven.size())
    {
        return NULL;
    }
    return mDriven[index].mParam;
}

//-----------------------------------------------------------------------------
// setAnimationTarget()
//-----------------------------------------------------------------------------
void LLDriverParam::setAnimationTarget( F32 target_value)
{
    LLVisualParam::setAnimationTarget(target_value);

    for(LLDrivenEntry& driven : mDriven)
    {
        LLDrivenEntry* drivenp = &driven;
        F32 driven_weight = getDrivenWeight(drivenp, mTargetWeight);

        // this isn't normally necessary, as driver params handle interpolation of their driven params
        // but texture params need to know to assume their final value at beginning of interpolation
        drivenp->mParam->setAnimationTarget(driven_weight);
    }
}

//-----------------------------------------------------------------------------
// stopAnimating()
//-----------------------------------------------------------------------------
void LLDriverParam::stopAnimating()
{
    LLVisualParam::stopAnimating();

    for(LLDrivenEntry& driven : mDriven)
    {
        driven.mParam->setAnimating(false);
    }
}

/*virtual*/
bool LLDriverParam::linkDrivenParams(visual_param_mapper mapper, bool only_cross_params)
{
    bool success = true;
    for (LLDrivenEntryInfo& driven_info : getInfo()->mDrivenInfoList)
    {
        S32 driven_id = driven_info.mDrivenID;

        // check for already existing links. Do not overwrite.
        bool found = false;
        for (auto& driven : mDriven)
        {
            if (driven.mInfo->mDrivenID == driven_id)
            {
                found = true;
            }
        }

        if (!found)
        {
            LLViewerVisualParam* param = (LLViewerVisualParam*)mapper(driven_id);
            if (param) param->setParamLocation(this->getParamLocation());
            bool push = param && (!only_cross_params || param->getCrossWearable());
            if (push)
            {
                mDriven.push_back(LLDrivenEntry( param, &driven_info ));
            }
            else
            {
                success = false;
            }
        }
    }

    return success;
}

void LLDriverParam::resetDrivenParams()
{
    mDriven.clear();
    mDriven.reserve(getInfo()->mDrivenInfoList.size());
}

void LLDriverParam::updateCrossDrivenParams(LLWearableType::EType driven_type)
{
    bool needs_update = (getWearableType()==driven_type);

    // if the driver has a driven entry for the passed-in wearable type, we need to refresh the value
    for(LLDrivenEntry& driven : mDriven)
    {
        if (driven.mParam && driven.mParam->getCrossWearable() && driven.mParam->getWearableType() == driven_type)
        {
            needs_update = true;
        }
    }


    if (needs_update)
    {
        LLWearableType::EType driver_type = (LLWearableType::EType)getWearableType();

        // If we've gotten here, we've added a new wearable of type "type"
        // Thus this wearable needs to get updates from the driver wearable.
        // The call to setVisualParamWeight seems redundant, but is necessary
        // as the number of driven wearables has changed since the last update. -Nyx
        LLWearable *wearable = mAvatarAppearance->getWearableData()->getTopWearable(driver_type);
        if (wearable)
        {
            wearable->setVisualParamWeight(mID, wearable->getVisualParamWeight(mID));
        }
    }
}


//-----------------------------------------------------------------------------
// getDrivenWeight()
//-----------------------------------------------------------------------------
F32 LLDriverParam::getDrivenWeight(const LLDrivenEntry* driven, F32 input_weight)
{
    F32 min_weight = getMinWeight();
    F32 max_weight = getMaxWeight();
    const LLDrivenEntryInfo* info = driven->mInfo;

    F32 driven_weight = 0.f;
    F32 driven_min = driven->mParam->getMinWeight();
    F32 driven_max = driven->mParam->getMaxWeight();

    if( input_weight <= info->mMin1 )
    {
        if( info->mMin1 == info->mMax1 &&
            info->mMin1 <= min_weight)
        {
            driven_weight = driven_max;
        }
        else
        {
            driven_weight = driven_min;
        }
    }
    else
    if( input_weight <= info->mMax1 )
    {
        F32 t = (input_weight - info->mMin1) / (info->mMax1 - info->mMin1 );
        driven_weight = driven_min + t * (driven_max - driven_min);
    }
    else
    if( input_weight <= info->mMax2 )
    {
        driven_weight = driven_max;
    }
    else
    if( input_weight <= info->mMin2 )
    {
        F32 t = (input_weight - info->mMax2) / (info->mMin2 - info->mMax2 );
        driven_weight = driven_max + t * (driven_min - driven_max);
    }
    else
    {
        if (info->mMax2 >= max_weight)
        {
            driven_weight = driven_max;
        }
        else
        {
            driven_weight = driven_min;
        }
    }

    return driven_weight;
}

void LLDriverParam::setDrivenWeight(LLDrivenEntry *driven, F32 driven_weight)
{
    bool use_self = false;
    if(mWearablep &&
        mAvatarAppearance->isValid() &&
        driven->mParam->getCrossWearable())
    {
        LLWearable* wearable = mWearablep;
        if (mAvatarAppearance->getWearableData()->isOnTop(wearable))
        {
            use_self = true;
        }
    }

    if (use_self)
    {
        // call setWeight through LLVOAvatarSelf so other wearables can be updated with the correct values
        mAvatarAppearance->setVisualParamWeight( (LLVisualParam*)driven->mParam, driven_weight);
    }
    else
    {
        driven->mParam->setWeight( driven_weight);
    }
}