/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011 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::IOobject

Description
    IOobject defines the attributes of an object for which implicit
    objectRegistry management is supported, and provides the infrastructure
    for performing stream I/O.

    An IOobject is constructed with an object name, a class name, an instance
    path, a reference to a objectRegistry, and parameters determining its
    storage status.

    \par Read options

    Define what is done on object construction and explicit reads:
    \param MUST_READ
        Object must be read from Istream on construction. \n
        Error if Istream does not exist or can't be read.
        Does not check timestamp or re-read.
    \param MUST_READ_IF_MODIFIED
        Object must be read from Istream on construction. \n
        Error if Istream does not exist or can't be read. If object is
        registered its timestamp will be checked every timestep and possibly
        re-read.
    \param READ_IF_PRESENT
        Read object from Istream if Istream exists, otherwise don't. \n
        Error only if Istream exists but can't be read.
        Does not check timestamp or re-read.
    \param NO_READ
          Don't read

    \par Write options

    Define what is done on object destruction and explicit writes:
    \param AUTO_WRITE
        Object is written automatically when requested to by the
        objectRegistry.
    \param NO_WRITE
        No automatic write on destruction but can be written explicitly

SourceFiles
    IOobject.C
    IOobjectReadHeader.C
    IOobjectWriteHeader.C
    IOobjectPrint.C

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

#ifndef IOobject_H
#define IOobject_H

#include "fileName.H"
#include "typeInfo.H"
#include "autoPtr.H"
#include "InfoProxy.H"

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

namespace Foam
{

class Time;
class objectRegistry;

/*---------------------------------------------------------------------------*\
                           Class IOobject Declaration
\*---------------------------------------------------------------------------*/

class IOobject
{

public:

    // Public data types

        //- Enumeration defining the valid states of an IOobject
        enum objectState
        {
            GOOD,
            BAD
        };

        //- Enumeration defining the read options
        enum readOption
        {
            MUST_READ,
            MUST_READ_IF_MODIFIED,
            READ_IF_PRESENT,
            NO_READ
        };

        //- Enumeration defining the write options
        enum writeOption
        {
            AUTO_WRITE = 0,
            NO_WRITE = 1
        };


private:

    // Private data

        //- Name
        word name_;

        //- Class name read from header
        word headerClassName_;

        //- Optional note
        string note_;

        //- Instance path component
        fileName instance_;

        //- Local path component
        fileName local_;

        //- objectRegistry reference
        const objectRegistry& db_;

        //- Read option
        readOption rOpt_;

        //- Write option
        writeOption wOpt_;

        //- Register object created from this IOobject with registry if true
        bool registerObject_;

        //- IOobject state
        objectState objState_;

private:

    // Private member functions

        //- Unique on disk file name.
        const word& uniqueFileName() const;

protected:

    // Protected Member Functions

        //- Construct and return an IFstream for the object.
        //  The results is NULL if the stream construction failed
        Istream* objectStream();

        //- Construct and return an IFstream for the object given the
        //  exact file. The results is NULL if the stream construction failed
        Istream* objectStream(const fileName&);

        //- Set the object state to bad
        void setBad(const string&);


public:

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


    // Static Member Functions

        //- Split path into instance, local, name components
        static bool fileNameComponents
        (
            const fileName& path,
            fileName& instance,
            fileName& local,
            word& name
        );


    // Constructors

        //- Construct from name, instance, registry, io options
        IOobject
        (
            const word& name,
            const fileName& instance,
            const objectRegistry& registry,
            readOption r=NO_READ,
            writeOption w=NO_WRITE,
            bool registerObject=true
        );

        //- Construct from name, instance, local, registry, io options
        IOobject
        (
            const word& name,
            const fileName& instance,
            const fileName& local,
            const objectRegistry& registry,
            readOption r=NO_READ,
            writeOption w=NO_WRITE,
            bool registerObject=true
        );

        //- Construct from path, registry, io options
        //  Uses fileNameComponents() to split path into components.
        IOobject
        (
            const fileName& path,
            const objectRegistry& registry,
            readOption r=NO_READ,
            writeOption w=NO_WRITE,
            bool registerObject=true
        );

        //- Clone
        Foam::autoPtr<IOobject> clone() const
        {
            return autoPtr<IOobject>(new IOobject(*this));
        }


    //- Destructor
    virtual ~IOobject();


    // Member Functions

        // General access

            //- Return time
            const Time& time() const;

            //- Return the local objectRegistry
            const objectRegistry& db() const;

            //- Return name
            const word& name() const
            {
                return name_;
            }

            //- Return name of the class name read from header
            const word& headerClassName() const
            {
                return headerClassName_;
            }

            //- Return non-constant access to the optional note
            string& note()
            {
                return note_;
            }

            //- Return the optional note
            const string& note() const
            {
                return note_;
            }

            //- Rename
            virtual void rename(const word& newName)
            {
                name_ = newName;
            }

            //- Register object created from this IOobject with registry if true
            bool registerObject() const
            {
                return registerObject_;
            }


        // Read/write options

            readOption readOpt() const
            {
                return rOpt_;
            }

            readOption& readOpt()
            {
                return rOpt_;
            }

            writeOption writeOpt() const
            {
                return wOpt_;
            }

            writeOption& writeOpt()
            {
                return wOpt_;
            }


        // Path components

            const fileName& rootPath() const;

            const fileName& caseName() const;

            const fileName& instance() const
            {
                return instance_;
            }

            fileName& instance()
            {
                return instance_;
            }

            const fileName& local() const
            {
                return local_;
            }

            //- Return complete path
            fileName path() const;

            //- Return complete path with alternative instance and local
            fileName path
            (
                const word& instance,
                const fileName& local = ""
            ) const;

            //- Return complete path + object name
            fileName objectPath() const
            {
                return path()/uniqueFileName();
            }

            //- Return complete path + object name if the file exists
            //  either in the case/processor or case otherwise null
            fileName filePath() const;


        // Reading

            //- Read header
            bool readHeader(Istream&);

            //- Read and check header info
            bool headerOk();


        // Writing

            //- Write the standard OpenFOAM file/dictionary banner
            //  Optionally without -*- C++ -*- editor hint (eg, for logs)
            template<class Stream>
            static inline Stream& writeBanner(Stream& os, bool noHint=false);

            //- Write the standard file section divider
            template<class Stream>
            static inline Stream& writeDivider(Stream& os);

            //- Write the standard end file divider
            template<class Stream>
            static inline Stream& writeEndDivider(Stream& os);

            //- Write header
            bool writeHeader(Ostream&) const;

            //- Write header. Allow override of type
            bool writeHeader(Ostream&, const word& objectType) const;


        // Error Handling

            bool good() const
            {
                return objState_ == GOOD;
            }

            bool bad() const
            {
                return objState_ == BAD;
            }


        // Info

            //- Return info proxy.
            //  Used to print token information to a stream
            InfoProxy<IOobject> info() const
            {
                return *this;
            }


    // Member operators

        void operator=(const IOobject&);

    // Static functions

        //- Set unique on disk file name 
        //- e.g., b -> b_ to avoid upper/lowercase clash with B
        static void replaceFileName(const word& from, const word& to);
};


#if defined (__GNUC__)
template<>
#endif
Ostream& operator<<(Ostream& os, const InfoProxy<IOobject>& ip);


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

} // End namespace Foam

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

#   include "IOobjectI.H"

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

#endif

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