// SPDX-FileCopyrightText: 2009 Manjeet Dahiya <manjeetdahiya@gmail.com>
// SPDX-FileCopyrightText: 2010 Jeremy Lainé <jeremy.laine@m4x.org>
//
// SPDX-License-Identifier: LGPL-2.1-or-later

#ifndef QXMPPSTREAM_H
#define QXMPPSTREAM_H

#include "QXmppLogger.h"
#include "QXmppSendResult.h"

#include <memory>
#include <variant>

#include <QAbstractSocket>
#include <QObject>

class QDomElement;
template<typename T>
class QXmppTask;
template<typename T>
class QFuture;
template<typename T>
class QFutureInterface;
class QSslSocket;
class QXmppIq;
class QXmppNonza;
class QXmppPacket;
class QXmppStanza;
class QXmppStreamPrivate;

///
/// \brief The QXmppStream class is the base class for all XMPP streams.
///
class QXMPP_EXPORT QXmppStream : public QXmppLoggable
{
    Q_OBJECT

public:
    QXmppStream(QObject *parent);
    ~QXmppStream() override;

    virtual bool isConnected() const;

    bool sendPacket(const QXmppNonza &);
    QXmppTask<QXmpp::SendResult> send(QXmppNonza &&);
    QXmppTask<QXmpp::SendResult> send(QXmppPacket &&);

    using IqResult = std::variant<QDomElement, QXmppError>;
    QXmppTask<IqResult> sendIq(QXmppIq &&, const QString &to);
    QXmppTask<IqResult> sendIq(QXmppPacket &&, const QString &id, const QString &to);
    void cancelOngoingIqs();
    bool hasIqId(const QString &id) const;

    void resetPacketCache();

Q_SIGNALS:
    /// This signal is emitted when the stream is connected.
    void connected();

    /// This signal is emitted when the stream is disconnected.
    void disconnected();

protected:
    // Access to underlying socket
    QSslSocket *socket() const;
    void setSocket(QSslSocket *socket);

    // Overridable methods
    virtual void handleStart();

    /// Handles an incoming XMPP stanza.
    ///
    /// \param element
    virtual void handleStanza(const QDomElement &element) = 0;

    /// Handles an incoming XMPP stream start.
    ///
    /// \param element
    virtual void handleStream(const QDomElement &element) = 0;

    // XEP-0198: Stream Management
    void enableStreamManagement(bool resetSequenceNumber);
    unsigned int lastIncomingSequenceNumber() const;
    void setAcknowledgedSequenceNumber(unsigned int sequenceNumber);

public Q_SLOTS:
    virtual void disconnectFromHost();
    virtual bool sendData(const QByteArray &);

private Q_SLOTS:
    void _q_socketConnected();
    void _q_socketEncrypted();
    void _q_socketError(QAbstractSocket::SocketError error);
    void _q_socketReadyRead();

private:
    friend class QXmppStreamManager;
    friend class tst_QXmppStream;
    friend class TestClient;

    QXmppTask<QXmpp::SendResult> send(QXmppPacket &&, bool &);
    void processData(const QString &data);
    bool handleIqResponse(const QDomElement &);

    QXmppStreamPrivate *const d;
};

#endif  // QXMPPSTREAM_H