/*
    This file is part of Konsole, an X terminal.

    Copyright 2006-2008 by Robert Knight <robertknight@gmail.com>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU Lesser 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 Lesser General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301  USA.
*/

// Own
#include "TerminalCharacterDecoder.h"

// Qt
#include <QtCore/QTextStream>

// KDE
#include <KDebug>

// Konsole
#include "konsole_wcwidth.h"

using namespace Konsole;
PlainTextDecoder::PlainTextDecoder()
 : _output(0)
 , _includeTrailingWhitespace(true)
 , _recordLinePositions(false)
{

}
void PlainTextDecoder::setTrailingWhitespace(bool enable)
{
    _includeTrailingWhitespace = enable;
}
bool PlainTextDecoder::trailingWhitespace() const
{
    return _includeTrailingWhitespace;
}
void PlainTextDecoder::begin(QTextStream* output)
{
   _output = output;
   if (!_linePositions.isEmpty())
       _linePositions.clear();
}
void PlainTextDecoder::end()
{
    _output = 0;
}

void PlainTextDecoder::setRecordLinePositions(bool record)
{
    _recordLinePositions = record;
}
QList<int> PlainTextDecoder::linePositions() const
{
    return _linePositions;
}
void PlainTextDecoder::decodeLine(const Character* const characters, int count, LineProperty /*properties*/
                             )
{
    Q_ASSERT( _output );

    if (_recordLinePositions && _output->string())
    {
        int pos = _output->string()->count();
        _linePositions << pos;
    }

    //TODO should we ignore or respect the LINE_WRAPPED line property?

    //note:  we build up a QString and send it to the text stream rather writing into the text
    //stream a character at a time because it is more efficient.
    //(since QTextStream always deals with QStrings internally anyway)
    QString plainText;
    plainText.reserve(count);

    int outputCount = count;

    // if inclusion of trailing whitespace is disabled then find the end of the
    // line
    if ( !_includeTrailingWhitespace )
    {
        for (int i = count-1 ; i >= 0 ; i--)
        {
            if ( !characters[i].isSpace() )
                break;
            else
                outputCount--;
        }
    }

    // find out the last technically real character in the line
    int guard = -1 ;
    for (int i = count-1 ; i >= 0 ; i--)
    {
        // FIXME: the special case of '\n' here is really ugly
        // Maybe the '\n' should be added after calling this method in
        // Screen::copyLineToStream()
        if ( characters[i].isRealCharacter && characters[i].character != '\n' )
        {
            guard = i;
            break;
        }
    }

    for (int i=0;i<outputCount;)
    {
        if (characters[i].rendition & RE_EXTENDED_CHAR)
        {
            ushort extendedCharLength = 0;
            const ushort* chars = ExtendedCharTable::instance.lookupExtendedChar(characters[i].character, extendedCharLength);
            if (chars)
            {
                const QString s = QString::fromUtf16(chars, extendedCharLength);
                plainText.append(s);
                i += qMax(1, string_width(s));
            }
        }
        else
        {
            // All characters which appear before the last real character are
            // seen as real characters, even when they are technically marked as
            // non-real.
            //
            // This feels tricky, but otherwise leading "whitespaces" may be
            // lost in some situation. One typical example is copying the result
            // of `dialog --infobox "qwe" 10 10` .
            if ( characters[i].isRealCharacter || i <= guard )
            {
                plainText.append( QChar(characters[i].character) );
                i += qMax(1,konsole_wcwidth(characters[i].character));
            }
            else
            {
                ++i;  // should we 'break' directly here?
            }
        }
    }
    *_output << plainText;
}

HTMLDecoder::HTMLDecoder() :
        _output(0)
    ,_colorTable(base_color_table)
       ,_innerSpanOpen(false)
       ,_lastRendition(DEFAULT_RENDITION)
{

}

void HTMLDecoder::begin(QTextStream* output)
{
    _output = output;

    QString text;

    //open monospace span
    openSpan(text,"font-family:monospace");

    *output << text;
}

void HTMLDecoder::end()
{
    Q_ASSERT( _output );

    QString text;

    closeSpan(text);

    *_output << text;

    _output = 0;

}

//TODO: Support for LineProperty (mainly double width , double height)
void HTMLDecoder::decodeLine(const Character* const characters, int count, LineProperty /*properties*/
                            )
{
    Q_ASSERT( _output );

    QString text;

    int spaceCount = 0;

    for (int i=0;i<count;i++)
    {
        //check if appearance of character is different from previous char
        if ( characters[i].rendition != _lastRendition  ||
             characters[i].foregroundColor != _lastForeColor  ||
             characters[i].backgroundColor != _lastBackColor )
        {
            if ( _innerSpanOpen )
                    closeSpan(text);

            _lastRendition = characters[i].rendition;
            _lastForeColor = characters[i].foregroundColor;
            _lastBackColor = characters[i].backgroundColor;

            //build up style string
            QString style;

            bool useBold;
            ColorEntry::FontWeight weight = characters[i].fontWeight(_colorTable);
            if (weight == ColorEntry::UseCurrentFormat)
                useBold = _lastRendition & RE_BOLD;
            else
                useBold = weight == ColorEntry::Bold;

            if (useBold)
                style.append("font-weight:bold;");

            if ( _lastRendition & RE_UNDERLINE )
                    style.append("font-decoration:underline;");

            //colors - a color table must have been defined first
            if ( _colorTable )    
            {
                style.append( QString("color:%1;").arg(_lastForeColor.color(_colorTable).name() ) );

                if (!characters[i].isTransparent(_colorTable))
                {
                    style.append( QString("background-color:%1;").arg(_lastBackColor.color(_colorTable).name() ) );
                }
            }

            //open the span with the current style    
            openSpan(text,style);
            _innerSpanOpen = true;
        }

        //handle whitespace
        if (characters[i].isSpace())
            spaceCount++;
        else
            spaceCount = 0;


        //output current character
        if (spaceCount < 2)
        {
            if (characters[i].rendition & RE_EXTENDED_CHAR)
            {
                ushort extendedCharLength = 0;
                const ushort* chars = ExtendedCharTable::instance.lookupExtendedChar(characters[i].character, extendedCharLength);
                if (chars)
                {
                    text.append(QString::fromUtf16(chars, extendedCharLength));
                }
            }
            else
            {
                //escape HTML tag characters and just display others as they are
                const QChar ch = characters[i].character;
                if ( ch == '<' )
                    text.append("&lt;");
                else if (ch == '>')
                    text.append("&gt;");
                else    
                    text.append(ch);
            }
        }
        else
        {
            text.append("&nbsp;"); //HTML truncates multiple spaces, so use a space marker instead
        }

    }

    //close any remaining open inner spans
    if ( _innerSpanOpen )
        closeSpan(text);

    //start new line
    text.append("<br>");

    *_output << text;
}
void HTMLDecoder::openSpan(QString& text , const QString& style)
{
    text.append( QString("<span style=\"%1\">").arg(style) );
}

void HTMLDecoder::closeSpan(QString& text)
{
    text.append("</span>");
}

void HTMLDecoder::setColorTable(const ColorEntry* table)
{
    _colorTable = table;
}
