/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Copyright (C) 2011-2025 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/>.

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

#include "IFstream.H"
#include "OSspecific.H"
#include "gzstream.h"

// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //

namespace Foam
{
    defineTypeNameAndDebug(IFstream, 0);
}


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

Foam::IFstreamAllocator::IFstreamAllocator(const fileName& filePath)
:
    ifPtr_(nullptr),
    compression_(IOstream::UNCOMPRESSED)
{
    if (filePath.empty())
    {
        if (IFstream::debug)
        {
            InfoInFunction << "Cannot open null file " << endl;
        }
    }

    ifPtr_ = new ifstream(filePath.c_str());

    // If the file is compressed, decompress it before reading.
    if (!ifPtr_->good())
    {
        if (isFile(filePath + ".gz", false, true))
        {
            delete ifPtr_;

            if (IFstream::debug)
            {
                InfoInFunction << "Decompressing " << filePath + ".gz" << endl;
            }

            ifPtr_ = new igzstream((filePath + ".gz").c_str());

            if (ifPtr_->good())
            {
                compression_ = IOstream::COMPRESSED;
            }
        }
        else if (isFile(filePath + ".orig", false, true))
        {
            delete ifPtr_;

            ifPtr_ = new ifstream((filePath + ".orig").c_str());
        }
    }
}


Foam::IFstreamAllocator::~IFstreamAllocator()
{
    delete ifPtr_;
}


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

Foam::IFstream::IFstream
(
    const fileName& filePath,
    const streamFormat format,
    const versionNumber version
)
:
    IFstreamAllocator(filePath),
    ISstream
    (
        *ifPtr_,
        "IFstream.sourceFile_",
        format,
        version,
        IFstreamAllocator::compression_
    ),
    filePath_(filePath)
{
    setClosed();

    setState(ifPtr_->rdstate());

    if (!good())
    {
        if (debug)
        {
            InfoInFunction
                << "Could not open file for input" << endl << info() << endl;
        }

        setBad();
    }
    else
    {
        setOpened();
    }

    lineNumber_ = 1;
}


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

Foam::IFstream::~IFstream()
{}


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

std::istream& Foam::IFstream::stdStream()
{
    if (!ifPtr_)
    {
        FatalErrorInFunction
            << "No stream allocated" << abort(FatalError);
    }
    return *ifPtr_;
}


const std::istream& Foam::IFstream::stdStream() const
{
    if (!ifPtr_)
    {
        FatalErrorInFunction
            << "No stream allocated" << abort(FatalError);
    }
    return *ifPtr_;
}


void Foam::IFstream::print(Ostream& os) const
{
    // Print File data
    os  << "IFstream: ";
    ISstream::print(os);
}


// * * * * * * * * * * * * * * Member Operators  * * * * * * * * * * * * * * //

Foam::IFstream& Foam::IFstream::operator()() const
{
    if (!good())
    {
        // also checks variants
        if (isFile(filePath_, true, true))
        {
            check("IFstream::operator()");
            FatalIOError.exit();
        }
        else
        {
            FatalIOErrorInFunction(*this)
                << "file " << filePath_ << " does not exist"
                << exit(FatalIOError);
        }
    }

    return const_cast<IFstream&>(*this);
}


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