/*  This file is part of the KDE libraries and the Kate part.
 *
 *  Copyright (C) 2007 David Nolden <david.nolden.kdevelop@art-master.de>
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Library General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Library General Public License for more details.
 *
 *  You should have received a copy of the GNU Library General Public License
 *  along with this library; see the file COPYING.LIB.  If not, write to
 *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 *  Boston, MA 02110-1301, USA.
 */

#include "katecompletiondelegate.h"

#include <ktexteditor/codecompletionmodel.h>

#include "katerenderer.h"
#include "katetextline.h"
#include "katedocument.h"
#include "kateview.h"
#include "katehighlight.h"
#include "katerenderrange.h"

#include "katecompletionwidget.h"
#include "katecompletionmodel.h"
#include "katecompletiontree.h"

//Currently disable because it doesn't work
#define DISABLE_INTERNAL_HIGHLIGHTING

KateCompletionDelegate::KateCompletionDelegate(ExpandingWidgetModel* model, KateCompletionWidget* parent) :
    ExpandingDelegate(model, parent), m_cachedRow(-1)
{
}

void KateCompletionDelegate::adjustStyle( const QModelIndex& index, QStyleOptionViewItem & option ) const {
    if(index.column() == 0) {
        //We always want to use the match-color if available, also for highlighted items.
        ///@todo Only do this for the "current" item, for others the model is asked for the match color.
        uint color = model()->matchColor(index);
        if(color != 0) {
            QColor match(color);

            for(int a = 0; a <=2; a++ )
            option.palette.setColor( (QPalette::ColorGroup)a, QPalette::Highlight, match );
        }
    }
}


KateRenderer * KateCompletionDelegate::renderer( ) const
{
  return widget()->view()->renderer();
}

KateCompletionWidget * KateCompletionDelegate::widget( ) const
{
  return static_cast<KateCompletionWidget*>(const_cast<QObject*>(parent()));
}

KateDocument * KateCompletionDelegate::document( ) const
{
  return widget()->view()->doc();
}

void KateCompletionDelegate::heightChanged() const {
  if(parent())
    widget()->updateHeight();
}

QList<QTextLayout::FormatRange> KateCompletionDelegate::createHighlighting(const QModelIndex& index, QStyleOptionViewItem& option) const {

    QVariant highlight = model()->data(index, KTextEditor::CodeCompletionModel::HighlightingMethod);

    // TODO: config enable specifying no highlight as default
    int highlightMethod = KTextEditor::CodeCompletionModel::InternalHighlighting;
    if (highlight.canConvert(QVariant::Int))
      highlightMethod = highlight.toInt();

    if (highlightMethod & KTextEditor::CodeCompletionModel::CustomHighlighting) {
        m_currentColumnStart = 0;
        return highlightingFromVariantList(model()->data(index, KTextEditor::CodeCompletionModel::CustomHighlight).toList());
    }

#ifdef DISABLE_INTERNAL_HIGHLIGHTING
    return QList<QTextLayout::FormatRange>();
#endif

    if( index.row() == m_cachedRow && highlightMethod & KTextEditor::CodeCompletionModel::InternalHighlighting ) {

        if( index.column() < m_cachedColumnStarts.size() ) {
            m_currentColumnStart = m_cachedColumnStarts[index.column()];
        } else {
            kWarning() << "Column-count does not match";
        }

        return m_cachedHighlights;
    }

    ///@todo reset the cache when the model changed
    m_cachedRow = index.row();

    KTextEditor::Cursor completionStart = widget()->completionRange()->start().toCursor();

    QString startText = document()->text(KTextEditor::Range(completionStart.line(), 0, completionStart.line(), completionStart.column()));

    QString lineContent = startText;

    int len = completionStart.column();
    m_cachedColumnStarts.clear();

    for (int i = 0; i < KTextEditor::CodeCompletionModel::ColumnCount; ++i) {
      m_cachedColumnStarts.append(len);
      QString text = model()->data(model()->index(index.row(), i, index.parent()), Qt::DisplayRole).toString();
      lineContent += text;
      len += text.length();
    }

    Kate::TextLine thisLine = Kate::TextLine (new Kate::TextLineData(lineContent));

    //kDebug( 13035 ) << "About to highlight with mode " << highlightMethod << " text [" << thisLine->string() << "]";

    if (highlightMethod & KTextEditor::CodeCompletionModel::InternalHighlighting) {
      Kate::TextLine previousLine;
      if (completionStart.line())
        previousLine = document()->kateTextLine(completionStart.line() - 1);
      else
        previousLine = Kate::TextLine (new Kate::TextLineData());
      
      Kate::TextLine nextLine;
      if ((completionStart.line() + 1) < document()->lines())
        nextLine = document()->kateTextLine(completionStart.line() + 1);
      else
        nextLine = Kate::TextLine (new Kate::TextLineData());

      bool ctxChanged = false;
      document()->highlight()->doHighlight(previousLine.data(), thisLine.data(), nextLine.data(), ctxChanged);
    }

  m_currentColumnStart = m_cachedColumnStarts[index.column()];

  NormalRenderRange rr;
  QList<QTextLayout::FormatRange> ret = renderer()->decorationsForLine(thisLine, 0, false, &rr, option.state & QStyle::State_Selected);

  //Remove background-colors
  for( QList<QTextLayout::FormatRange>::iterator it = ret.begin(); it != ret.end(); ++it )
    (*it).format.clearBackground();

  return ret;
}