/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2013-2014 OpenFOAM Foundation
     \\/     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 3 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, see <http://www.gnu.org/licenses/>.

Class
    Foam::setTimeStepFunctionObject

Group
    grpUtilitiesFunctionObjects

Description
    This function object overrides the calculation time step. Can only be used
    with solvers with adjustTimeStep control (e.g. pimpleFoam).  It makes no
    attempt to co-operate with other time step 'controllers', e.g. maxCo, other
    functionObjects. Supports 'enabled' flag but none of the other options
    'timeStart', 'timeEnd', 'outputControl' etc.


    Example of function object specification to manipulate the time step:
    \verbatim
    setTimeStep1
    {
        type        setTimeStep;
        functionObjectLibs ("libutilityFunctionObjects.so");
        ...
    }
    \endverbatim

    \heading Function object usage
    \table
        Property     | Description             | Required    | Default value
        type         | Type name: setTimeStep  | yes         |
        enabled      | On/off switch           | no          | yes
    \endtable

SourceFiles
    setTimeStepFunctionObject.C

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

#ifndef setTimeStepFunctionObject_H
#define setTimeStepFunctionObject_H

#include "functionObject.H"
#include "dictionary.H"
#include "DataEntry.H"
#include "Switch.H"

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

namespace Foam
{

/*---------------------------------------------------------------------------*\
                    Class setTimeStepFunctionObject Declaration
\*---------------------------------------------------------------------------*/

class setTimeStepFunctionObject
:
    public functionObject
{
    // Private data

        //- Reference to the time database
        const Time& time_;


        // Optional user inputs

            //- Switch for the execution - defaults to 'yes/on'
            Switch enabled_;

            //- Time step
            autoPtr<DataEntry<scalar> > timeStepPtr_;


        //- Disallow default bitwise copy construct
        setTimeStepFunctionObject(const setTimeStepFunctionObject&);

        //- Disallow default bitwise assignment
        void operator=(const setTimeStepFunctionObject&);


public:

    //- Runtime type information
    TypeName("setTimeStep");

    // Constructors

        //- Construct from components
        setTimeStepFunctionObject
        (
            const word& name,
            const Time& runTime,
            const dictionary& dict
        );


    // Member Functions

        // Access

            //- Return time database
            virtual const Time& time() const
            {
                return time_;
            }

            //- Return the enabled flag
            virtual bool enabled() const
            {
                return enabled_;
            }


        // Function object control

            //- Switch the function object on
            virtual void on();

            //- Switch the function object off
            virtual void off();

            //- Called at the start of the time-loop
            virtual bool start();

            //- Called at each ++ or += of the time-loop
            virtual bool execute(const bool forceWrite);

            //- Called when Time::run() determines that the time-loop exits
            virtual bool end();

            //- Called when time was set at the end of the Time::operator++
            virtual bool timeSet();

            //- Called at the end of Time::adjustDeltaT() if adjustTime is true
            virtual bool adjustTimeStep();

            //- Read and set the function object if its data have changed
            virtual bool read(const dictionary&);

            //- Update for changes of mesh
            virtual void updateMesh(const mapPolyMesh& mpm);

            //- Update for changes of mesh
            virtual void movePoints(const polyMesh& mesh);
};

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

} // End namespace Foam

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

#endif

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