status-desktop/ui/StatusQ/include/StatusQ/fastexpressionsorter.h

#pragma once

#include <sorters/sorter.h>

#include <QQmlContext>
#include <QQmlExpression>
#include <QQmlScriptString>
#include <QSet>
#include <QQmlPropertyMap>

#include <memory>

class FastExpressionSorter : public qqsfpm::Sorter
{
    Q_OBJECT
    Q_PROPERTY(QQmlScriptString expression READ expression
               WRITE setExpression NOTIFY expressionChanged)

    Q_PROPERTY(QSet<QByteArray> expectedRoles READ expectedRoles
               WRITE setExpectedRoles NOTIFY expectedRolesChanged)
public:

    using qqsfpm::Sorter::Sorter;

    const QQmlScriptString& expression() const;
    void setExpression(const QQmlScriptString& scriptString);

    void proxyModelCompleted(const qqsfpm::QQmlSortFilterProxyModel& proxyModel) override;

    void setExpectedRoles(const QSet<QByteArray>& expectedRoles);
    const QSet<QByteArray>& expectedRoles() const;

    void queueInvalidate();
    void onInvalidate();

Q_SIGNALS:
    void expressionChanged();
    void expectedRolesChanged();

protected:
    int compare(const QModelIndex& sourceLeft, const QModelIndex& sourceRight, const qqsfpm::QQmlSortFilterProxyModel& proxyModel) const override;

private:
    void updateContext(const qqsfpm::QQmlSortFilterProxyModel& proxyModel);
    void updateExpression();

    QQmlScriptString m_scriptString;

    std::unique_ptr<QQmlExpression> m_expression;
    std::unique_ptr<QQmlContext> m_context;

    QSet<QByteArray> m_expectedRoles;

    bool m_queuedInvalidate { false };

    mutable QQmlPropertyMap m_modelLeftMap;
    mutable QQmlPropertyMap m_modelRightMap;
};