/////////////////////////////////////////////////////////////////////////////////
//
//  Copyright (C) 2011-2012 Statoil ASA, Ceetron AS
//
//  ResInsight 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.
//
//  ResInsight 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 at <http://www.gnu.org/licenses/gpl.html>
//  for more details.
//
/////////////////////////////////////////////////////////////////////////////////

#include "RiaImageFileCompare.h"
#include <QtCore/QProcess>

//==================================================================================================
//
//
//
//==================================================================================================

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
RiaImageFileCompare::RiaImageFileCompare( QString compareExecutable )
    : m_compareExecutable( compareExecutable )
{
    reset();
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
RiaImageFileCompare::~RiaImageFileCompare() {}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
void RiaImageFileCompare::reset()
{
    m_imagesEqual  = false;
    m_lastError    = IC_NO_ERROR;
    m_errorMsg     = "";
    m_errorDetails = "";
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
bool RiaImageFileCompare::runComparison( const QString& imgFileName,
                                         const QString& refFileName,
                                         const QString& diffFileName )
{
    reset();

    if ( m_compareExecutable.isEmpty() )
    {
        m_lastError = SEVERE_ERROR;
        m_errorMsg  = "Cannot compare images, no compare executable set";
        return false;
    }

    // QString args = QString("-fuzz 2% -lowlight-color white -metric ae \"%1\" \"%2\"
    // \"%3\"").arg(imgFileName).arg(refFileName).arg((diffFileName));
    // The ImageMagick compare tool on RedHat 5 does not support the lowlight-color options
    // Use GCC version as a crude mechanism for disabling use of this option on RedHat5
#if ( __GNUC__ == 4 && __GNUC_MINOR__ <= 1 )
    QString args = QString( "-fuzz 0.4% -metric ae \"%1\" \"%2\" \"%3\"" )
                       .arg( imgFileName )
                       .arg( refFileName )
                       .arg( ( diffFileName ) );
#else
    QString args = QString( "-fuzz 0.4% -lowlight-color white -metric ae \"%1\" \"%2\" \"%3\"" )
                       .arg( imgFileName )
                       .arg( refFileName )
                       .arg( ( diffFileName ) );
#endif
    QString completeCommand = QString( "\"%1\" %2" ).arg( m_compareExecutable ).arg( args );

    // Launch process and wait
    QProcess proc;
    proc.start( completeCommand );
    proc.waitForFinished( 30000 );

    QProcess::ProcessError procError = proc.error();
    if ( procError != QProcess::UnknownError )
    {
        m_lastError    = SEVERE_ERROR;
        m_errorMsg     = "Error running compare tool process";
        m_errorDetails = completeCommand;
        return false;
    }

    QByteArray stdErr       = proc.readAllStandardError();
    int        procExitCode = proc.exitCode();
    if ( procExitCode == 0 )
    {
        // Strip out whitespace and look for 0 (as in zero pixel differences)
        stdErr = stdErr.simplified();
        if ( !stdErr.isEmpty() && stdErr[0] == '0' )
        {
            m_imagesEqual = true;
        }

        return true;
    }
    else
    {
        // Report non-severe error
        m_lastError    = IC_ERROR;
        m_errorMsg     = "Error running compare tool process";
        m_errorDetails = stdErr;

        return false;
    }
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
bool RiaImageFileCompare::imagesEqual() const
{
    return m_imagesEqual;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
RiaImageFileCompare::ErrorType RiaImageFileCompare::error() const
{
    return m_lastError;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
QString RiaImageFileCompare::errorMessage() const
{
    return m_errorMsg;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
QString RiaImageFileCompare::errorDetails() const
{
    return m_errorDetails;
}