/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright held by original author
     \\/     M anipulation  |
-------------------------------------------------------------------------------
License
    This file is part of OpenFOAM.

    OpenFOAM is free software; you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by the
    Free Software Foundation; either version 2 of the License, or (at your
    option) any later version.

    OpenFOAM 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 General Public License
    for more details.

    You should have received a copy of the GNU General Public License
    along with OpenFOAM; if not, write to the Free Software Foundation,
    Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

\*---------------------------------------------------------------------------*/

#include "constantVelocity.H"
#include "addToRunTimeSelectionTable.H"
#include "mathematicalConstants.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

namespace Foam
{
namespace solidBodyMotionFunctions
{

defineTypeNameAndDebug(constantVelocity, 0);
addToRunTimeSelectionTable
(
    solidBodyMotionFunction,
    constantVelocity,
    dictionary
);

}
}

// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //

Foam::septernion
Foam::solidBodyMotionFunctions::constantVelocity::calcTransformation
(
    const scalar t
) const
{
    const vector translation = transVelocity_*(t - startMotionTime_);
    const vector rotation = rotVelocity_*(t - startMotionTime_);

    const   quaternion R(rotation.x(), rotation.y(), rotation.z());
    const   septernion TR
        (
            septernion(origin_ + translation)*R*septernion(-origin_)
        );

    return TR;
}

// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //

Foam::solidBodyMotionFunctions::constantVelocity::constantVelocity
(
    const dictionary& SBMFCoeffs,
    const Time& runTime
)
:
    solidBodyMotionFunction(SBMFCoeffs, runTime)
{
    read(SBMFCoeffs);
}

// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //

Foam::septernion
Foam::solidBodyMotionFunctions::constantVelocity::transformation() const
{
   const scalar t = time_.value();

   const septernion TR = calcTransformation(t);

   Info<< "solidBodyMotionFunctions::constantVelocity::transformation(): "
   << "Time = " << t << " transformation: " << TR << endl;

   return TR;
}


Foam::septernion
Foam::solidBodyMotionFunctions::constantVelocity::velocity() const
{
    const scalar t = time_.value();
    const scalar dt = time_.deltaT().value();

    const septernion velocity
    (
        (calcTransformation(t).t() - calcTransformation(t - dt).t())/dt,
        (calcTransformation(t).r()/calcTransformation(t - dt).r())/dt
    );

    return velocity;
}


bool Foam::solidBodyMotionFunctions::constantVelocity::read
(
    const dictionary& SBMFCoeffs
)
{
    solidBodyMotionFunction::read(SBMFCoeffs);

    SBMFCoeffs_.lookup("origin") >> origin_;
    SBMFCoeffs_.lookup("translationalVelocity") >> transVelocity_;
    SBMFCoeffs_.lookup("rotationalVelocity") >> rotVelocity_;
    SBMFCoeffs_.lookup("startMotionTime") >> startMotionTime_;
    SBMFCoeffs_.lookup("inDegrees") >> inDegrees_;

    // Convert to radians if necessary
    rotVelocity_ *= inDegrees_ ? mathematicalConstant::pi/180.0 : 1;

    return true;
}

// ************************************************************************* //