JsonBackend.h

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// SPDX-FileCopyrightText: 2026 fuddlesworth
// SPDX-License-Identifier: LGPL-2.1-or-later
 
#pragma once
 
#include <phosphorconfig_export.h>
 
#include <PhosphorConfig/IBackend.h>
 
#include <QJsonObject>
#include <QString>
 
#include <memory>
 
QT_BEGIN_NAMESPACE
class QTimer;
QT_END_NAMESPACE
 
namespace PhosphorConfig {
 
class IGroupPathResolver;
class JsonBackend;
 
class PHOSPHORCONFIG_EXPORT JsonGroup : public IGroup
{
public:
    JsonGroup(QJsonObject& root, QString groupName, JsonBackend* backend);
    ~JsonGroup() override;
 
    QString readString(const QString& key, const QString& defaultValue = {}) const override;
    int readInt(const QString& key, int defaultValue = 0) const override;
    bool readBool(const QString& key, bool defaultValue = false) const override;
    double readDouble(const QString& key, double defaultValue = 0.0) const override;
    QColor readColor(const QString& key, const QColor& defaultValue = {}) const override;
 
    void writeString(const QString& key, const QString& value) override;
    void writeInt(const QString& key, int value) override;
    void writeBool(const QString& key, bool value) override;
    void writeDouble(const QString& key, double value) override;
    void writeColor(const QString& key, const QColor& value) override;
    void writeJson(const QString& key, const QJsonValue& value) override;
    QJsonValue readJson(const QString& key, const QJsonValue& defaultValue = {}) const override;
 
    bool hasKey(const QString& key) const override;
    void deleteKey(const QString& key) override;
    QStringList keyList() const override;
 
private:
    QJsonObject groupObject() const;
    void setGroupObject(const QJsonObject& obj);
    bool refuseWrite(const char* op) const;
 
    QJsonObject& m_root;
    QString m_groupName;
    JsonBackend* m_backend;
    bool m_disabled = false;
};
 
class PHOSPHORCONFIG_EXPORT JsonBackend : public IBackend
{
public:
    explicit JsonBackend(QString filePath);
    ~JsonBackend() override;
 
    // IBackend interface
    std::unique_ptr<IGroup> group(const QString& name) override;
    void reparseConfiguration() override;
    bool sync() override;
    void deleteGroup(const QString& name) override;
    QString readRootString(const QString& key, const QString& defaultValue = {}) const override;
    void writeRootString(const QString& key, const QString& value) override;
    void removeRootKey(const QString& key) override;
    QStringList groupList() const override;
 
    void setPathResolver(std::shared_ptr<IGroupPathResolver> resolver) override;
    std::shared_ptr<IGroupPathResolver> pathResolver() const override;
 
    void setRootGroupName(const QString& name);
    QString rootGroupName() const;
 
    void setVersionStamp(const QString& key, int version) override;
 
    std::pair<QString, int> versionStamp() const override;
 
    bool applyMigration(const Schema& schema) override;
 
    static bool writeJsonAtomically(const QString& filePath, const QJsonObject& root);
 
    QJsonObject jsonRootSnapshot() const;
 
    QString filePath() const;
 
    void clearDirty();
 
    void replaceRoot(QJsonObject root);
 
    enum class SyncPolicy {
        Synchronous,
        Deferred,
    };
 
    void setSyncPolicy(SyncPolicy policy, int debounceMs = 500);
    SyncPolicy syncPolicy() const;
 
    bool flushPending();
 
private:
    friend class JsonGroup;
 
    void loadFromDisk();
    void markDirty();
    bool flushNow();
    void incActiveGroupCount();
    void decActiveGroupCount();
    int activeGroupCount() const;
 
    bool shouldWarnOnce(const char* tag, const QString& key);
 
    struct Data;
    std::unique_ptr<Data> d;
};
 
} // namespace PhosphorConfig