/******************************************************************************
*
* Copyright (C) 2002 Hugo PEREIRA <mailto: hugo.pereira@free.fr>
*
* This 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 software 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, see <http://www.gnu.org/licenses/>.
*
*******************************************************************************/

#include "SessionFilesModel.h"

#include "CppUtil.h"
#include "CustomPixmap.h"
#include "FileRecordProperties.h"
#include "IconNames.h"
#include "IconEngine.h"
#include "Singleton.h"
#include "XmlFileRecord.h"
#include "XmlOptions.h"
#include "QOrderedSet.h"

#include <QMimeData>
#include <QPalette>
#include <QSet>
#include <QUrl>

//__________________________________________________________________
SessionFilesModel::IconCache& SessionFilesModel::_icons()
{
    static IconCache cache;
    return cache;
}

//__________________________________________________________________
SessionFilesModel::SessionFilesModel( QObject* parent ):
    FileRecordModel( parent )
{

    Debug::Throw("SessionFilesModel::SessionFilesModel.\n" );
    setShowIcons( false );
    connect( Base::Singleton::get().application(), SIGNAL(configurationChanged()), SLOT(_updateConfiguration()) );

}

//__________________________________________________________________
Qt::ItemFlags SessionFilesModel::flags(const QModelIndex &index) const
{

    // get flags from parent class
    Qt::ItemFlags flags( FileRecordModel::flags( index ) );
    return flags | Qt::ItemIsDropEnabled;

}

//__________________________________________________________________
QVariant SessionFilesModel::data( const QModelIndex& index, int role ) const
{

    // check index, role and column
    if( !index.isValid() ) return QVariant();

    // retrieve associated file info
    const FileRecord& record( get(index) );

    if( role == Qt::DecorationRole && index.column() == Filename )
    {

        if( record.hasFlag( FileRecordProperties::Modified ) ) return _icon( FileRecordProperties::Modified );
        else if( record.hasFlag( FileRecordProperties::Altered ) ) return _icon( FileRecordProperties::Altered );
        else return _icon( FileRecordProperties::None );

    } else if( role == Qt::ForegroundRole ) {

        return record.hasFlag( FileRecordProperties::Active ) ?
            QPalette().color( QPalette::Text ):
            QPalette().color( QPalette::Disabled, QPalette::Text );

    } else return FileRecordModel::data( index, role );

    return QVariant();

}

//____________________________________________________________
void SessionFilesModel::_updateConfiguration()
{
    Debug::Throw( "SessionFilesModel::_updateConfiguration.\n" );
    _icons().clear();
}

//________________________________________________________
const QIcon& SessionFilesModel::_icon( int type )
{

    IconCache::const_iterator iter( _icons().find( type ) );
    if( iter != _icons().end() ) return iter.value();

    QIcon icon;
    if( type == FileRecordProperties::Modified ) icon = IconEngine::get( IconNames::Save );
    else if( type == FileRecordProperties::Altered ) icon = IconEngine::get( IconNames::DialogWarning );
    else if( type == FileRecordProperties::None )
    {

        const int iconSize( XmlOptions::get().get<int>( "LIST_ICON_SIZE" ) );
        QSize size( iconSize, iconSize );

        // update size to match real icon
        QIcon prototype( IconEngine::get( IconNames::Save ) );
        if( !prototype.isNull() ) size = prototype.actualSize( size );

        // create empty pixmap
        icon = CustomPixmap( size, CustomPixmap::Flag::Transparent );

    }

    // store in map and return
    return _icons().insert( type, icon ).value();

}

//______________________________________________________________________
QStringList SessionFilesModel::mimeTypes() const
{
    static const auto mimeTypes = Base::makeT<QStringList>( { FileRecord::MimeType, "text/uri-list" });
    return mimeTypes;
}

//______________________________________________________________________
QMimeData* SessionFilesModel::mimeData(const QModelIndexList &indexes) const
{

    // base class
    auto mimeData = FileRecordModel::mimeData( indexes );

    // get selected filenames
    QOrderedSet<QString> filenames;
    XmlFileRecord::List records;
    for( const auto& index:indexes )
    {

        if( !index.isValid() ) continue;
        XmlFileRecord record( get(index) );
        records.append( record );
        filenames.insert( record.file() );

    }

    if( filenames.empty() ) return mimeData;
    else {

        if( !mimeData ) mimeData = new QMimeData;

        // fill text data
        {
            QString fullText;
            QTextStream buffer( &fullText );
            for( const auto& filename:filenames )
            { buffer << QString( "file://%1" ).arg(filename) << endl; }
            mimeData->setText( fullText );
        }

        // fill url list
        {
            QList<QUrl> urlList;
            for( const auto& filename:filenames )
            { urlList.append( QUrl( QString( "file://%1" ).arg(filename) ) ); }
            mimeData->setUrls( urlList );
        }

        // fill drag data. Use XML
        QDomDocument document;
        XmlFileRecord::Helper::domElement( records, document );
        mimeData->setData( FileRecord::MimeType, document.toByteArray() );
        return mimeData;

    }

}

//__________________________________________________________________
bool SessionFilesModel::dropMimeData(const QMimeData* data , Qt::DropAction action, int, int, const QModelIndex& parent)
{

    // check action
    if( action == Qt::IgnoreAction) return true;

    if( data->hasFormat( FileRecord::MimeType ) )
    {

        // get dropped file record (use XML)
        // dom document
        QDomDocument document;
        if( !document.setContent( data->data( FileRecord::MimeType ), false ) ) return false;
        const XmlFileRecord::List records( XmlFileRecord::Helper::list( document.documentElement() ) );

        // get current record
        if( parent.isValid() )
        {

            FileRecord target( get( parent ) );

            // loop over sources and emit proper signal
            for( const auto& record:records )
            { emit reparentFiles( record.file(), target.file() ); }

            return true;

        } else {

            // look for first active file in this window
            FileRecord target;
            QModelIndex targetIndex;
            for( int row = 0; row < rowCount(); row++ )
            {

                QModelIndex index( SessionFilesModel::index( row, 0 ) );
                if( flags( index ) & Qt::ItemIsEnabled )
                {
                    FileRecord record( get( index ) );
                    if( record.hasFlag( FileRecordProperties::Active ) )
                    {
                        targetIndex = index;
                        target = record;
                        break;
                    }

                }
            }

            // check that targetIndex is valid
            if( !targetIndex.isValid() ) return false;

            // emit relevant reparent signal
            for( const auto& record:records )
            { emit reparentFilesToMain( record.file(), target.file() ); }

            return true;

        }

    } else if( data->hasUrls() ) {

        // TODO: should check number of files
        const auto urls( data->urls() );
        for( const auto& url:urls )
        {

            #if QT_VERSION >= 0x040800
            // check that local file
            if( !url.isLocalFile() ) continue;
            #endif

            // get file and check existence
            const File file( url.path() );
            if( file.exists() && !file.isDirectory() )
            { emit requestOpen( FileRecord( file ) ); }

        }

        return true;

    } else return false;

}