#pragma once

#include <QObject>
#include <QString>

// Delivers text produced by the keyboard to the focused application.
// Implementations hide the transport (KWin input method, uinput, XTest, ...).
// Keys are identified by XKB keysyms so every backend speaks the same language.
class TextBackend : public QObject
{
    Q_OBJECT
    Q_PROPERTY(bool active READ isActive NOTIFY activeChanged)
    Q_PROPERTY(QString surroundingText READ surroundingText NOTIFY surroundingChanged)
    Q_PROPERTY(int cursorPosition READ cursorPosition NOTIFY surroundingChanged)

public:
    using QObject::QObject;

    // True while a text field is focused and accepts input.
    virtual bool isActive() const = 0;

    // Text around the cursor, if the backend knows it (empty otherwise).
    virtual QString surroundingText() const { return {}; }
    virtual int cursorPosition() const { return -1; }

    Q_INVOKABLE virtual void commitText(const QString &text) = 0;
    Q_INVOKABLE virtual void setPreedit(const QString &text) = 0;
    Q_INVOKABLE virtual void sendKeysym(quint32 keysym, Qt::KeyboardModifiers modifiers = Qt::NoModifier) = 0;

Q_SIGNALS:
    void activeChanged();
    void surroundingChanged();
};