// SPDX-FileCopyrightText: 2021 Carl Schwan <carlschwan@kde.org>
//
// SPDX-License-Identifier: LGPL-2.1-or-later

#pragma once

#include "e2ee/e2ee.h"

#include <memory>
#include <olm/olm.h>

namespace Quotient {

//! An out-bound group session is responsible for encrypting outgoing
//! communication in a Megolm session.
class QUOTIENT_API QOlmOutboundGroupSession
{
public:
    ~QOlmOutboundGroupSession();
    //! Creates a new instance of `QOlmOutboundGroupSession`.
    //! Throw OlmError on errors
    static QOlmOutboundGroupSessionPtr create();
    //! Serialises a `QOlmOutboundGroupSession` to encrypted Base64.
    QOlmExpected<QByteArray> pickle(const PicklingMode &mode) const;
    //! Deserialises from encrypted Base64 that was previously obtained by
    //! pickling a `QOlmOutboundGroupSession`.
    static QOlmExpected<QOlmOutboundGroupSessionPtr> unpickle(
        const QByteArray& pickled, const PicklingMode& mode);

    //! Encrypts a plaintext message using the session.
    QOlmExpected<QByteArray> encrypt(const QString& plaintext) const;

    //! Get the current message index for this session.
    //!
    //! Each message is sent with an increasing index; this returns the
    //! index for the next message.
    uint32_t sessionMessageIndex() const;

    //! Get a base64-encoded identifier for this session.
    QByteArray sessionId() const;

    //! Get the base64-encoded current ratchet key for this session.
    //!
    //! Each message is sent with a different ratchet key. This function returns the
    //! ratchet key that will be used for the next message.
    QOlmExpected<QByteArray> sessionKey() const;
    QOlmOutboundGroupSession(OlmOutboundGroupSession *groupSession);

    int messageCount() const;
    void setMessageCount(int messageCount);

    QDateTime creationTime() const;
    void setCreationTime(const QDateTime& creationTime);
private:
    OlmOutboundGroupSession *m_groupSession;
    int m_messageCount = 0;
    QDateTime m_creationTime = QDateTime::currentDateTime();
};

} // namespace Quotient