settingsaccessor.h

/**************************************************************************
**
** This file is part of Qt Creator
**
** Copyright (c) 2012 Nokia Corporation and/or its subsidiary(-ies).
**
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**
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** GNU Lesser General Public License Usage
**
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** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this file.
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** Public License version 2.1 requirements will be met:
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**
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** rights. These rights are described in the Nokia Qt LGPL Exception
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#ifndef PROJECTMANAGER_USERFILEACCESSOR_H
#define PROJECTMANAGER_USERFILEACCESSOR_H

#include <utils/fileutils.h>

#include <QVariantMap>

namespace ProjectExplorer {

class Project;

namespace Internal {
class UserFileVersionHandler;
}

class SettingsAccessor
{
public:
    ~SettingsAccessor();

    static SettingsAccessor *instance();

    QVariantMap restoreSettings(Project *project) const;
    bool saveSettings(const Project *project, const QVariantMap &map) const;

private:
    SettingsAccessor();

    // Takes ownership of the handler!
    void addVersionHandler(Internal::UserFileVersionHandler *handler);

    // The relevant data from the settings currently in use.
    class SettingsData
    {
    public:
        SettingsData() : m_version(-1), m_usingBackup(false) {}
        SettingsData(const QVariantMap &map) : m_version(-1), m_usingBackup(false), m_map(map) {}

        void clear();
        bool isValid() const;

        int m_version;
        bool m_usingBackup;
        QVariantMap m_map;
        Utils::FileName m_fileName;
    };

    // The entity which actually reads/writes to the settings file.
    class FileAccessor
    {
    public:
        FileAccessor(const QByteArray &id,
                     const QString &defaultSuffix,
                     const QString &environmentSuffix,
                     bool envSpecific,
                     bool versionStrict);

        bool readFile(Project *project, SettingsData *settings) const;
        bool writeFile(const Project *project, const SettingsData *settings) const;

    private:
        void assignSuffix(const QString &defaultSuffix, const QString &environmentSuffix);
        QString assembleFileName(const Project *project) const;
        bool findNewestCompatibleSetting(SettingsData *settings) const;

        QByteArray m_id;
        QString m_suffix;
        bool m_environmentSpecific;
        bool m_versionStrict;
    };

    static bool verifyEnvironmentId(const QString &id);

    QMap<int, Internal::UserFileVersionHandler *> m_handlers;
    int m_firstVersion;
    int m_lastVersion;
    const FileAccessor m_userFileAcessor;
    const FileAccessor m_sharedFileAcessor;
};

} // namespace ProjectExplorer

#endif // PROJECTMANAGER_USERFILEACCESSOR_H