/**
 * @file PswGen/Storage/module.h
 * @brief Implementation of the iStorage interface
 * @author Enar Vaikene
 *
 * Copyright (c) 2011-2019 Enar Vaikene
 *
 * This file is part of the eVaf C++ cross-platform application development framework.
 *
 * This file can be used under the terms of the GNU General Public License
 * version 3.0 as published by the Free Software Foundation and appearing in
 * the file LICENSE included in the packaging of this file. Please review the
 * the following information to ensure the GNU General Public License version
 * 3.0 requirements will be met: http://www.gnu.org/copyleft/gpl.html.
 *
 * Alternatively, this file may be used in accordance with the Commercial License
 * Agreement provided with the Software.
 */

#ifndef __PSWGEN_STORAGE_MODULE_H
#  define __PSWGEN_STORAGE_MODULE_H

#include "istorage.h"
#include "version.h"

#include <Plugins/iPlugin>

#include <QObject>
#include <QString>
#include <QAbstractListModel>
#include <QMap>

class QSqlDatabase;

namespace eVaf {
namespace PswGen {

/// Module that stores options for strong passwords
namespace Storage {

/// Internal implementation of the Storage module
namespace Internal {
    class StorageImpl;
} // namespace eVaf::PswGen::Storage::Internal

/**
 * Module implementing the iStorage interface.
 */
class Module : public Plugins::iPlugin
{
    Q_OBJECT
    Q_INTERFACES(eVaf::Plugins::iPlugin)
    Q_PLUGIN_METADATA(IID VER_MODULE_NAME_STR)

public:

    Module();

    virtual ~Module();

    virtual bool init(QString const & args);

    virtual void done();

    virtual bool isReady() const { return mReady; }


private: // Members

    /// Flag indicating that the module is ready
    bool mReady;

    /// iStorage interface instance
    Internal::StorageImpl * mStorage;

};


namespace Internal {

/**
 * iStorage interface implementation.
 *
 * Implements the iStorage interface using a simple file storage.
 */

class StorageImpl : public QAbstractListModel, public iStorage
{
    Q_OBJECT
    Q_INTERFACES(eVaf::PswGen::iStorage)

public:

    StorageImpl();

    virtual ~StorageImpl();

    bool init();

    void done();

    /*
        iStorage interface
    */

    virtual bool save(QString const & name, QExplicitlySharedDataPointer<Storage::Data> data);

    virtual QExplicitlySharedDataPointer<Storage::Data> query(QString const & name) const;

    virtual QAbstractItemModel * autoCompletionModel() { return this; }

    /*
        QAbstractListModel methods
    */

    virtual int rowCount(QModelIndex const &) const { return mData.count(); }

    virtual QVariant data(QModelIndex const & index, int role = Qt::DisplayRole) const;


private: // Members

    /// Name of the database connection
    static char const * const DbConnectionName;

    /// Name of the database file without path
    static char const * const DbName;

    /// List of name/data pairs
    QMap<QString, QExplicitlySharedDataPointer<Storage::Data> > mData;


private: // Methods

    /**
     * Creates database tables if necessary
     * @return True if ok; false if failed
     */
    bool createTables(QSqlDatabase & db);

    /**
     * Upgrades database tables if necessary
     * @return True if ok; false if failed
     *
     * This function checks if database tables need to upgraded and
     * performs the upgrade without a loss of data if possible.
     * Returns false if upgrade is not possible or fails.
     */
    bool upgradeTables(QSqlDatabase & db);

    /**
     * Loads data from the database
     * @return True if ok; false if failed
     */
    bool loadData(QSqlDatabase & db);

};

} // namespace eVaf::PswGen::Storage::Internal


} // namespace eVaf::PswGen::Storage
} // namespace eVaf::PswGen
} // namespace eVaf

#endif // module.h