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#include "IElementField.hxx"

#include "IFieldManager.hxx"

COMET::IElementField::IElementField(const TVector3* translation, 
                                    const TRotation* rotation):
    fTranslation(NULL), fNeedTrans(false), fGlobalToLocalRotation(NULL), fLocalToGlobalRotation(NULL){
    if (translation) SetTranslation(*translation);
    if (rotation)    SetRotation(*rotation);
    addElementField();
}

void COMET::IElementField::GlobalToLocal(const Double_t GlobalPoint[4], Double_t LocalPoint[4]) const{
    //Apply translation and rotation of the element to go from global coord 
    //to local coord
    if (fNeedTrans){
        TVector3 local(GlobalPoint[0],GlobalPoint[1],GlobalPoint[2]);
        GlobalToLocal(local);

        LocalPoint[0]=local[0];
        LocalPoint[1]=local[1];
        LocalPoint[2]=local[2];
        LocalPoint[3]=GlobalPoint[3];
    }
    else{
        LocalPoint[0]=GlobalPoint[0];
        LocalPoint[1]=GlobalPoint[1];
        LocalPoint[2]=GlobalPoint[2];
        LocalPoint[3]=GlobalPoint[3];
    }
}

void COMET::IElementField::addFieldValue(const Double_t GlobalPoint[4], Double_t field[6]) const{
    if (!fNeedTrans){
        if(GlobalPoint[2] < fBoundingBox.MinZ || GlobalPoint[2] > fBoundingBox.MaxZ) return;
        if(GlobalPoint[0] < fBoundingBox.MinX || GlobalPoint[0] > fBoundingBox.MaxX) return;
        if(GlobalPoint[1] < fBoundingBox.MinY || GlobalPoint[1] > fBoundingBox.MaxY) return;
    }
    Double_t LocalPoint[4];
    GlobalToLocal(GlobalPoint,LocalPoint);
    if (fNeedTrans){
        if(LocalPoint[2] < fBoundingBox.MinZ || LocalPoint[2] > fBoundingBox.MaxZ) return;
        if(LocalPoint[0] < fBoundingBox.MinX || LocalPoint[0] > fBoundingBox.MaxX) return;
        if(LocalPoint[1] < fBoundingBox.MinY || LocalPoint[1] > fBoundingBox.MaxY) return;
    }

    Double_t f[6];
    f[0] = f[1] = f[2] = f[3] = f[4] = f[5] = 0.0;
    // get the field f in local coords
    getFieldValue(LocalPoint,f);
    
    //Rotate the fields and add to field[]
    if(fLocalToGlobalRotation){
        // Initialize rotatedField vector to handle rotation
        // Only use one vector to cut down on initialization time
        TVector3 rotatedField;
        rotatedField.SetXYZ(f[0], f[1], f[2]);
        rotatedField = (*fLocalToGlobalRotation) * rotatedField;
        // Return this to actual field result
        field[0] += rotatedField[0];
        field[1] += rotatedField[1];
        field[2] += rotatedField[2];
        // Do the same for the E field
        rotatedField.SetXYZ(f[3], f[4], f[5]);
        rotatedField = (*fLocalToGlobalRotation) * rotatedField;
        field[3] += rotatedField[0];
        field[4] += rotatedField[1];
        field[5] += rotatedField[2];
    } else for (int i = 0; i < 6; i++) field[i] += f[i];
}

void COMET::IElementField::addElementField() {
    if (IFieldManager::GetObject()->fFields)
        IFieldManager::GetObject()->fFields->push_back(this);
}