/******************************************************************************\
 * Copyright (c) 2004-2018
 *
 * Author(s):
 *  Volker Fischer
 *
 ******************************************************************************
 *
 * This program 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.
 *
 * This program 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
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
\******************************************************************************/

#include "serverlogging.h"


/* Implementation *************************************************************/
CHistoryGraph::CHistoryGraph() :
    sFileName ( "" ),
    bDoHistory ( false ),
    vHistoryDataFifo ( NUM_ITEMS_HISTORY ),
    PlotCanvasRect    ( 0, 0, 600, 450 ), // defines total size of graph
    iNumTicksX        ( 0 ), // just an initialization value, will be overwritten
    iYAxisStart       ( 0 ),
    iYAxisEnd         ( 24 ),
    iNumTicksY        ( 5 ),
    iGridFrameOffset  ( 10 ),
    iGridWidthWeekend ( 3 ), // should be an odd value
    iTextOffsetToGrid ( 3 ),
    iXAxisTextHeight  ( 22 ),
    iMarkerSizeNewCon ( 11 ),
    iMarkerSizeServSt ( 8 ),
    AxisFont ( "Arial", 12 ),
    iTextOffsetX      ( 18 ),
    PlotBackgroundColor     ( Qt::white ), // background
    PlotFrameColor          ( Qt::black ), // frame
    PlotGridColor           ( Qt::gray ), // grid
    PlotTextColor           ( Qt::black ), // text
    PlotMarkerNewColor      ( Qt::darkCyan ), // marker for new connection
    PlotMarkerNewLocalColor ( Qt::blue ), // marker for new local connection
    PlotMarkerStopColor     ( Qt::red ), // marker for server stop
    PlotPixmap ( 1, 1, QImage::Format_RGB32 )
{
    // generate plot grid frame rectangle
    PlotGridFrame.setRect ( PlotCanvasRect.x() + iGridFrameOffset,
        PlotCanvasRect.y() + iGridFrameOffset,
        PlotCanvasRect.width() - 2 * iGridFrameOffset,
        PlotCanvasRect.height() - 2 * iGridFrameOffset - iXAxisTextHeight );

    // scale pixmap to correct size
    PlotPixmap = PlotPixmap.scaled (
        PlotCanvasRect.width(), PlotCanvasRect.height() );


    // Connections -------------------------------------------------------------
    QObject::connect ( &TimerDailyUpdate, SIGNAL ( timeout() ),
        this, SLOT ( OnTimerDailyUpdate() ) );
}

void CHistoryGraph::Start ( const QString& sNewFileName )
{
    if ( !sNewFileName.isEmpty() )
    {
        // save file name
        sFileName = sNewFileName;

        // set enable flag
        bDoHistory = true;

        // enable timer (update once a day)
        TimerDailyUpdate.start ( 3600000 * 24 );

        // initial update (empty graph)
        Update();
    }
}

void CHistoryGraph::DrawFrame ( const int iNewNumTicksX )
{
    int i;

    // store number of x-axis ticks (number of days we want to draw
    // the history for
    iNumTicksX = iNewNumTicksX;

    // clear base pixmap for new plotting
    PlotPixmap.fill ( PlotBackgroundColor.rgb() ); // fill background

    // create painter
    QPainter PlotPainter ( &PlotPixmap );


    // Create actual plot region (grid frame) ----------------------------------
    PlotPainter.setPen ( PlotFrameColor );
    PlotPainter.drawRect ( PlotGridFrame );

    // calculate step for x-axis ticks so that we get the desired number of
    // ticks -> 5 ticks

// TODO the following equation does not work as expected but results are acceptable

    // we want to have "floor ( iNumTicksX / 5 )" which is the same as
    // "iNumTicksX / 5" since "iNumTicksX" is an integer variable
    const int iXAxisTickStep = iNumTicksX / 5 + 1;

    // grid (ticks) for x-axis
    dXSpace = static_cast<double> ( PlotGridFrame.width() ) / ( iNumTicksX + 1 );
    for ( i = 0; i < iNumTicksX; i++ )
    {
        int         iBottomExtraTickLen = 0;
        const int   iCurX = PlotGridFrame.x() + static_cast<int> ( dXSpace * ( i + 1 ) );
        const QDate curXAxisDate = curDate.addDays ( i - iNumTicksX + 1 );

        // text (print only every "iXAxisTickStep" tick)
        if ( !( i % iXAxisTickStep ) )
        {
            PlotPainter.setPen ( PlotTextColor );
            PlotPainter.setFont ( AxisFont );
            PlotPainter.drawText (
                QPoint ( iCurX - iTextOffsetX,
                PlotGridFrame.bottom() + iXAxisTextHeight + iTextOffsetToGrid ),
                curXAxisDate.toString ( "dd.MM." ) );

            iBottomExtraTickLen = 5;
        }

        // regular grid
        PlotPainter.setPen ( PlotGridColor );
        PlotPainter.drawLine ( iCurX, 1 + PlotGridFrame.y(),
            iCurX, PlotGridFrame.bottom() + iBottomExtraTickLen );

        // different grid width for weekends (overwrite regular grid)
        if ( ( curXAxisDate.dayOfWeek() == 6 ) || // check for Saturday
             ( curXAxisDate.dayOfWeek() == 7 ) )  // check for Sunday
        {
            const int iGridWidthWeekendHalf = iGridWidthWeekend / 2;

            PlotPainter.setPen ( QPen ( PlotGridColor, iGridWidthWeekend ) );
            PlotPainter.drawLine ( iCurX, 1 + PlotGridFrame.y() + iGridWidthWeekendHalf,
                iCurX, PlotGridFrame.bottom() - iGridWidthWeekendHalf );
        }
    }

    // grid (ticks) for y-axis, draw iNumTicksY - 2 grid lines and
    // iNumTicksY - 1 text labels (the lowest grid line is the grid frame)
    iYSpace = PlotGridFrame.height() / ( iNumTicksY - 1 );
    for ( i = 0; i < ( iNumTicksY - 1 ); i++ )
    {
        const int iCurY = PlotGridFrame.y() + iYSpace * ( i + 1 );

        // text
        PlotPainter.setPen ( PlotTextColor );
        PlotPainter.setFont ( AxisFont );
        PlotPainter.drawText ( QPoint (
            PlotGridFrame.x() + iTextOffsetToGrid,
            iCurY - iTextOffsetToGrid ),
            QString ( "%1:00" ).arg (
            ( iYAxisEnd - iYAxisStart ) / ( iNumTicksY - 1 ) *
            ( ( iNumTicksY - 2 ) - i ) ) );

        // grid (do not overwrite frame)
        if ( i < ( iNumTicksY - 2 ) )
        {
            PlotPainter.setPen ( PlotGridColor );
            PlotPainter.drawLine ( PlotGridFrame.x(), iCurY,
                PlotGridFrame.right(), iCurY );
        }
    }
}

void CHistoryGraph::AddMarker ( const SHistoryData& curHistoryData )
{
    // calculate x-axis offset (difference of days compared to
    // current date)
    const int iXAxisOffs =
        curDate.daysTo ( curHistoryData.DateTime.date() );

    // check range, if out of range, do not plot anything
    if ( -iXAxisOffs > ( iNumTicksX - 1 ) )
    {
        return;
    }

    // calculate y-axis offset (consider hours and minutes)
    const double dYAxisOffs = 24 - curHistoryData.DateTime.time().hour() -
        static_cast<double> ( curHistoryData.DateTime.time().minute() ) / 60;

    // calculate the actual point in the graph (in pixels)
    const QPoint curPoint (
        PlotGridFrame.x() + static_cast<int> ( dXSpace * ( iNumTicksX + iXAxisOffs ) ),
        PlotGridFrame.y() + static_cast<int> ( static_cast<double> (
        PlotGridFrame.height() ) / ( iYAxisEnd - iYAxisStart ) * dYAxisOffs ) );

    // create painter for plot
    QPainter PlotPainter ( &PlotPixmap );

    // we use different markers for new connection and server stop items
    switch ( curHistoryData.Type )
    {
    case HIT_SERVER_STOP:
        PlotPainter.setPen ( QPen ( QBrush ( PlotMarkerStopColor ),
            iMarkerSizeServSt ) );
        break;

    case HIT_LOCAL_CONNECTION:
        PlotPainter.setPen ( QPen ( QBrush ( PlotMarkerNewLocalColor ),
            iMarkerSizeNewCon ) );
        break;

    case HIT_REMOTE_CONNECTION:
        PlotPainter.setPen ( QPen ( QBrush ( PlotMarkerNewColor ),
            iMarkerSizeNewCon ) );
        break;
    }
    PlotPainter.drawPoint ( curPoint );
}

void CHistoryGraph::Save ( const QString sFileName )
{
    // save plot as a file
    PlotPixmap.save ( sFileName, "JPG", 90 );
}

void CHistoryGraph::Add ( const QDateTime&   newDateTime,
                          const QHostAddress ClientInetAddr )
{
    if ( bDoHistory )
    {
        // add element to history, distinguish between a local connection
        // and a remote connection
        if ( ( ClientInetAddr == QHostAddress ( "127.0.0.1" ) ) ||
             ( ClientInetAddr.toString().left ( 7 ).compare ( "192.168" ) == 0 ) )
        {
            // local connection
            Add ( newDateTime, CHistoryGraph::HIT_LOCAL_CONNECTION );
        }
        else
        {
            // remote connection
            Add ( newDateTime, CHistoryGraph::HIT_REMOTE_CONNECTION );
        }
    }
}

void CHistoryGraph::Add ( const QDateTime& newDateTime,
                          const EHistoryItemType curType )
{
    if ( bDoHistory )
    {
        // create and add new element in FIFO
        SHistoryData curHistoryData;
        curHistoryData.DateTime = newDateTime;
        curHistoryData.Type     = curType;

        vHistoryDataFifo.Add ( curHistoryData );
    }
}

void CHistoryGraph::Update()
{
    if ( bDoHistory )
    {
        int i;

        // store current date for reference
        curDate = QDate::currentDate();

        // get oldest date in history
        QDate oldestDate = curDate.addDays ( 1 ); // one day in the future
        const int iNumItemsForHistory = vHistoryDataFifo.Size();
        for ( i = 0; i < iNumItemsForHistory; i++ )
        {
            // only use valid dates
            if ( vHistoryDataFifo[i].DateTime.date().isValid() )
            {
                if ( vHistoryDataFifo[i].DateTime.date() < oldestDate )
                {
                    oldestDate = vHistoryDataFifo[i].DateTime.date();
                }
            }
        }
        const int iNumDaysInHistory = -curDate.daysTo ( oldestDate ) + 1;

        // draw frame of the graph
        DrawFrame ( iNumDaysInHistory );

        // add markers
        for ( i = 0; i < iNumItemsForHistory; i++ )
        {
            // only use valid dates
            if ( vHistoryDataFifo[i].DateTime.date().isValid() )
            {
                AddMarker ( vHistoryDataFifo[i] );
            }
        }

        // save graph as picture in file
        Save ( sFileName );
    }
}


// Server logging --------------------------------------------------------------
CServerLogging::~CServerLogging()
{
    // close logging file of open
    if ( File.isOpen() )
    {
        File.close();
    }
}

void CServerLogging::Start ( const QString& strLoggingFileName )
{
    // open file
    File.setFileName ( strLoggingFileName );
    if ( File.open ( QIODevice::Append | QIODevice::Text ) )
    {
        bDoLogging = true;
    }
}

void CServerLogging::EnableHistory ( const QString& strHistoryFileName )
{
    HistoryGraph.Start ( strHistoryFileName );
}

void CServerLogging::AddNewConnection ( const QHostAddress& ClientInetAddr )
{
    // logging of new connected channel
    const QString strLogStr = CurTimeDatetoLogString() + ", " +
        ClientInetAddr.toString() + ", connected";


    QTextStream* tsConsoleStream = (new ConsoleWriterFactory())->get();
    (*tsConsoleStream) << strLogStr << endl; // on console

    *this << strLogStr; // in log file

    // add element to history
    HistoryGraph.Add ( QDateTime::currentDateTime(), ClientInetAddr );
}

void CServerLogging::AddServerStopped()
{
    const QString strLogStr = CurTimeDatetoLogString() + ",, server stopped "
        "-------------------------------------";


    QTextStream* tsConsoleStream = (new ConsoleWriterFactory())->get();
    (*tsConsoleStream) << strLogStr << endl; // on console

    *this << strLogStr; // in log file

    // add element to history and update on server stop
    HistoryGraph.Add ( QDateTime::currentDateTime(),
        CHistoryGraph::HIT_SERVER_STOP );

    HistoryGraph.Update();
}

void CServerLogging::operator<< ( const QString& sNewStr )
{
    if ( bDoLogging )
    {
        // append new line in logging file
        QTextStream out ( &File );
        out << sNewStr << endl;
        File.flush();
    }
}

void CServerLogging::ParseLogFile ( const QString& strFileName )
{
    // open file for reading
    QFile LogFile ( strFileName );
    LogFile.open ( QIODevice::ReadOnly | QIODevice::Text );

    QTextStream inStream ( &LogFile );

    // read all content from file
    while ( !inStream.atEnd() )
    {
        // get a new line from log file
        QString strCurLine = inStream.readLine();

        // parse log file line
        QStringList strlistCurLine = strCurLine.split( "," );

        // check number of separated strings condition
        if ( strlistCurLine.size() == 4 )
        {
            // first entry
            QDate curDate =
                QDate::fromString ( strlistCurLine.at ( 0 ).trimmed(),
                "d.M.yyyy" );

            // second entry
            QTime curTime =
                QTime::fromString ( strlistCurLine.at ( 1 ).trimmed(),
                "hh:mm:ss" );

            if ( curDate.isValid() && curTime.isValid() )
            {
                QDateTime curDateTime ( curDate, curTime );

                // check if server stop or new client connection
                QString strAddress = strlistCurLine.at ( 2 ).trimmed();
                if ( strAddress.isEmpty() )
                {
                    // server stop
                    HistoryGraph.Add ( curDateTime,
                        CHistoryGraph::HIT_SERVER_STOP );
                }
                else
                {
                    QHostAddress curAddress;
                    
                    // third entry is IP address
                    if ( curAddress.setAddress ( strlistCurLine.at ( 2 ).trimmed() ) )
                    {
                        // new client connection
                        HistoryGraph.Add ( curDateTime, curAddress );
                    }
                }
            }
        }
    }

     HistoryGraph.Update();
}

QString CServerLogging::CurTimeDatetoLogString()
{
    // time and date to string conversion
    const QDateTime curDateTime = QDateTime::currentDateTime();

    // format date and time output according to "3.9.2006, 11:38:08"
    return QString().setNum ( curDateTime.date().day() ) + "." +
        QString().setNum ( curDateTime.date().month() ) + "." +
        QString().setNum ( curDateTime.date().year() ) + ", " +
        curDateTime.time().toString();
}