/*
  Copyright (C) 2010 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.net,
    Author: Tobias Koenig <tokoe@kdab.com>

  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 "snippetsmodel_p.h"

#include <QMimeData>
#include <QStringList>

using namespace MailCommon;

class MailCommon::SnippetItem
{
public:
    SnippetItem( bool isGroup = false, SnippetItem *parent = 0 );
    ~SnippetItem();

    bool isGroup() const;

    void setName( const QString &name );
    QString name() const;

    void setText( const QString &text );
    QString text() const;

    void setKeySequence( const QString &sequence );
    QString keySequence() const;

    void appendChild( SnippetItem *child );
    void removeChild( SnippetItem *child );
    SnippetItem *child( int row ) const;
    int childCount() const;
    int row() const;
    SnippetItem *parent() const;

private:
    QList<SnippetItem*> mChildItems;
    SnippetItem *mParentItem;

    bool mIsGroup;
    QString mName;
    QString mText;
    QString mKeySequence;
};

SnippetItem::SnippetItem( bool isGroup, SnippetItem *parent )
    : mParentItem( parent ), mIsGroup( isGroup )
{
}

SnippetItem::~SnippetItem()
{
    qDeleteAll( mChildItems );
    mChildItems.clear();
}

bool SnippetItem::isGroup() const
{
    return mIsGroup;
}

void SnippetItem::setName( const QString &name )
{
    mName = name;
}

QString SnippetItem::name() const
{
    return mName;
}

void SnippetItem::setText( const QString &text )
{
    mText = text;
}

QString SnippetItem::text() const
{
    return mText;
}

void SnippetItem::setKeySequence( const QString &sequence )
{
    mKeySequence = sequence;
}

QString SnippetItem::keySequence() const
{
    return mKeySequence;
}

void SnippetItem::appendChild( SnippetItem *item )
{
    mChildItems.append( item );
}

void SnippetItem::removeChild( SnippetItem *item )
{
    mChildItems.removeAll( item );
    delete item;
}

SnippetItem *SnippetItem::child( int row ) const
{
    return mChildItems.value( row );
}

int SnippetItem::childCount() const
{
    return mChildItems.count();
}

SnippetItem *SnippetItem::parent() const
{
    return mParentItem;
}

int SnippetItem::row() const
{
    if ( mParentItem ) {
        return mParentItem->mChildItems.indexOf( const_cast<SnippetItem*>( this ) );
    }

    return 0;
}

SnippetsModel::SnippetsModel( QObject *parent )
    : QAbstractItemModel( parent )
{
    mRootItem = new SnippetItem( true );

    QHash<int, QByteArray> names = roleNames();

    names.insert( IsGroupRole, "isSnippetGroup" );

    setRoleNames( names );
}

SnippetsModel::~SnippetsModel()
{
    delete mRootItem;
}

int SnippetsModel::columnCount( const QModelIndex & ) const
{
    return 1;
}

bool SnippetsModel::setData( const QModelIndex &index, const QVariant &value, int role )
{
    if ( !index.isValid() ) {
        return false;
    }

    SnippetItem *item = static_cast<SnippetItem*>( index.internalPointer() );
    Q_ASSERT( item );

    switch ( role ) {
    case NameRole:
        item->setName( value.toString() );
        emit dataChanged( index, index );
        return true;
        break;
    case TextRole:
        item->setText( value.toString() );
        emit dataChanged( index, index );
        return true;
        break;
    case KeySequenceRole:
        item->setKeySequence( value.toString() );
        emit dataChanged( index, index );
        return true;
        break;
    default:
        return false;
        break;
    }

    return false;
}

QVariant SnippetsModel::data( const QModelIndex &index, int role ) const
{
    if ( !index.isValid() ) {
        return QVariant();
    }

    SnippetItem *item = static_cast<SnippetItem*>( index.internalPointer() );

    switch ( role ) {
    case Qt::DisplayRole:
        return item->name();
        break;
    case IsGroupRole:
        return item->isGroup();
        break;
    case NameRole:
        return item->name();
        break;
    case TextRole:
        return item->text();
        break;
    case KeySequenceRole:
        return item->keySequence();
        break;
    }

    return QVariant();
}

Qt::ItemFlags SnippetsModel::flags( const QModelIndex &index ) const
{
    Qt::ItemFlags defaultFlags = QAbstractItemModel::flags( index );

    if ( index.isValid() ) {
        const SnippetItem *item = static_cast<SnippetItem*>( index.internalPointer() );
        if ( !item->isGroup() ) {
            return Qt::ItemIsDragEnabled | Qt::ItemIsDropEnabled | defaultFlags;
        }
    }

    return Qt::ItemIsDropEnabled | defaultFlags;
}

QModelIndex SnippetsModel::index( int row, int column, const QModelIndex &parent ) const
{
    if ( !hasIndex( row, column, parent ) ) {
        return QModelIndex();
    }

    SnippetItem *parentItem;

    if ( !parent.isValid() ) {
        parentItem = mRootItem;
    } else {
        parentItem = static_cast<SnippetItem*>( parent.internalPointer() );
    }

    SnippetItem *childItem = parentItem->child( row );
    if ( childItem ) {
        return createIndex( row, column, childItem );
    } else {
        return QModelIndex();
    }
}

QModelIndex SnippetsModel::parent( const QModelIndex &index ) const
{
    if ( !index.isValid() ) {
        return QModelIndex();
    }

    SnippetItem *childItem = static_cast<SnippetItem*>( index.internalPointer() );
    SnippetItem *parentItem = childItem->parent();

    if ( parentItem == mRootItem ) {
        return QModelIndex();
    }

    return createIndex( parentItem->row(), 0, parentItem );
}

int SnippetsModel::rowCount( const QModelIndex &parent ) const
{
    SnippetItem *parentItem;
    if ( parent.column() > 0 ) {
        return 0;
    }

    if ( !parent.isValid() ) {
        parentItem = mRootItem;
    } else {
        parentItem = static_cast<SnippetItem*>( parent.internalPointer() );
    }

    return parentItem->childCount();
}

bool SnippetsModel::insertRows( int row, int count, const QModelIndex &parent )
{
    SnippetItem *parentItem;

    if ( !parent.isValid() ) {
        parentItem = mRootItem;
    } else {
        parentItem = static_cast<SnippetItem*>( parent.internalPointer() );
    }

    beginInsertRows( parent, row, row + count - 1 );
    for ( int i = 0; i < count; ++i ) {
        SnippetItem * snippet = new SnippetItem( !parent.isValid(), parentItem );
        parentItem->appendChild( snippet );
    }
    endInsertRows();

    return true;
}

bool SnippetsModel::removeRows( int row, int count, const QModelIndex &parent )
{
    SnippetItem *parentItem;

    if ( !parent.isValid() ) {
        parentItem = mRootItem;
    } else {
        parentItem = static_cast<SnippetItem*>( parent.internalPointer() );
    }

    beginRemoveRows( parent, row, row + count - 1 );
    for ( int i = 0; i < count; ++i ) {
        parentItem->removeChild( parentItem->child( row ) );
    }
    endRemoveRows();

    return true;
}

QStringList SnippetsModel::mimeTypes() const
{
    return
            QStringList() << QLatin1String( "text/x-kmail-textsnippet" )
                          << QLatin1String( "text/plain" );
}

QMimeData *SnippetsModel::mimeData( const QModelIndexList &indexes ) const
{
    if ( indexes.isEmpty() ) {
        return 0;
    }

    const QModelIndex index = indexes.first();

    SnippetItem *item = static_cast<SnippetItem*>( index.internalPointer() );
    if ( item->isGroup() ) {
        return 0;
    }

    QMimeData *mimeData = new QMimeData();

    QByteArray encodedData;
    QDataStream stream( &encodedData, QIODevice::WriteOnly );
    stream << index.parent().internalId()<< item->name() << item->text() <<item->keySequence();

    mimeData->setData( QLatin1String( "text/x-kmail-textsnippet" ), encodedData );
    mimeData->setText( item->text() );

    return mimeData;
}

bool SnippetsModel::dropMimeData( const QMimeData *data, Qt::DropAction action,
                                  int row, int column, const QModelIndex &parent )
{
    Q_UNUSED( row );

    if ( action == Qt::IgnoreAction ) {
        return true;
    }

    if ( !parent.isValid() ) {
        return false;
    }

    if ( !data->hasFormat( QLatin1String( "text/x-kmail-textsnippet" ) ) ) {
        return false;
    }

    if ( column > 1 ) {
        return false;
    }

    SnippetItem *item = static_cast<SnippetItem*>( parent.internalPointer() );

    if ( !item->isGroup() ) {
        return false;
    }

    QByteArray encodedData = data->data( QLatin1String( "text/x-kmail-textsnippet" ) );
    QDataStream stream( &encodedData, QIODevice::ReadOnly );

    qint64 id;
    QString name;
    QString text;
    QString keySequence;
    stream >> id >> name >> text >> keySequence;

    if ( parent.internalId() == id ) {
        return false;
    }

    insertRow( rowCount( parent ), parent );

    const QModelIndex idx = index( rowCount( parent )-1, 0, parent );

    setData( idx, name, SnippetsModel::NameRole );
    setData( idx, text, SnippetsModel::TextRole );
    setData( idx, keySequence, SnippetsModel::KeySequenceRole );
    emit dndDone();
    return true;
}

Qt::DropActions SnippetsModel::supportedDropActions () const
{
    return Qt::CopyAction|Qt::MoveAction;
}