/****************************************************************************
**
** Copyright (C) 1992-2005 Trolltech AS. All rights reserved.
**
** This file is part of the QtSql module of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file.  Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://www.trolltech.com/products/qt/licensing.html or contact the
** sales department at sales@trolltech.com.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
****************************************************************************/

#ifndef QSQLRELATIONALTABLEMODEL_H
#define QSQLRELATIONALTABLEMODEL_H

#include <QtSql/qsqltablemodel.h>

QT_MODULE(Sql)

class Q_SQL_EXPORT QSqlRelation
{
public:
    QSqlRelation() {}
    QSqlRelation(const QString &aTableName, const QString &indexCol,
               const QString &displayCol)
        : tName(aTableName), iColumn(indexCol), dColumn(displayCol) {}
    inline QString tableName() const
    { return tName; }
    inline QString indexColumn() const
    { return iColumn; }
    inline QString displayColumn() const
    { return dColumn; }
    inline bool isValid() const
    { return !(tName.isEmpty() || iColumn.isEmpty() || dColumn.isEmpty()); }
private:
    QString tName, iColumn, dColumn;
};

class QSqlRelationalTableModelPrivate;

class Q_SQL_EXPORT QSqlRelationalTableModel: public QSqlTableModel
{
    Q_OBJECT

public:
    explicit QSqlRelationalTableModel(QObject *parent = 0,
                                      QSqlDatabase db = QSqlDatabase());
    virtual ~QSqlRelationalTableModel();

    QVariant data(const QModelIndex &item, int role = Qt::DisplayRole) const;
    bool setData(const QModelIndex &item, const QVariant &value, int role = Qt::EditRole);

    void clear();
    bool select();

    void setTable(const QString &tableName);
    virtual void setRelation(int column, const QSqlRelation &relation);
    QSqlRelation relation(int column) const;
    virtual QSqlTableModel *relationModel(int column) const;

public Q_SLOTS:
    void revertRow(int row);

protected:
    QString selectStatement() const;
    bool updateRowInTable(int row, const QSqlRecord &values);
    QString orderByClause() const;

private:
    Q_DECLARE_PRIVATE(QSqlRelationalTableModel)
};

#endif // QSQLRELATIONALTABLEMODEL_H
