// SPDX-FileCopyrightText: 2025 Linus Jahn <lnj@kaidan.im>
//
// SPDX-License-Identifier: LGPL-2.1-or-later

#ifndef QXMPPMUCMANAGERV2_H
#define QXMPPMUCMANAGERV2_H

#include "QXmppClientExtension.h"
#include "QXmppMessageHandler.h"
#include "QXmppMucData.h"
#include "QXmppMucForms.h"
#include "QXmppSendResult.h"
#include "QXmppTask.h"

#include <chrono>
#include <memory>
#include <optional>
#include <variant>

class QXmppDataForm;
class QXmppPresence;
namespace QXmpp::Private {
struct MucRoomData;
struct MucParticipantData;
}  // namespace QXmpp::Private

class QXmppError;

class QXmppMucRoomV2;
class QXmppMucParticipant;
struct QXmppMucManagerV2Private;

class QXMPP_EXPORT QXmppMucManagerV2 : public QXmppClientExtension, public QXmppMessageHandler
{
    Q_OBJECT

public:
    QXmppMucManagerV2();
    ~QXmppMucManagerV2();

    QStringList discoveryFeatures() const override;

    QBindable<QStringList> mucServices() const;
    QBindable<bool> mucServicesLoaded() const;

    std::chrono::milliseconds selfPingSilenceThreshold() const;
    void setSelfPingSilenceThreshold(std::chrono::milliseconds threshold);

    /*!
        Returns a handle for the tracked room at \a jid, or \c std::nullopt if the manager
        has no state for this JID.

        Inactive rooms (left but still referenced by a caller handle) are revived transparently
        so that leave → findRoom observes the same underlying state.
    */
    std::optional<QXmppMucRoomV2> findRoom(const QString &jid);

    QXmppTask<QXmpp::Result<QXmppMucRoomV2>> joinRoom(const QString &jid, const QString &nickname);
    /*!
        \overload

        Joins the room with optional \a history request parameters and an optional \a password
        for password-protected rooms (\xep{0045}{Multi-User Chat} §7.2.5).
    */
    QXmppTask<QXmpp::Result<QXmppMucRoomV2>> joinRoom(const QString &jid, const QString &nickname,
                                                      std::optional<QXmpp::Muc::HistoryOptions> history,
                                                      const QString &password = {});
    QXmppTask<QXmpp::Result<QString>> requestUniqueRoomName(QString serviceJid);
    QXmppTask<QXmpp::Result<QXmppMucRoomV2>> createRoom(QString serviceJid,
                                                        QString nickname,
                                                        std::optional<QString> roomName = std::nullopt);
    /*! Emitted when \a participant joins the room at \a roomJid. */
    Q_SIGNAL void participantJoined(const QString &roomJid, const QXmppMucParticipant &participant);
    /*! Emitted when \a participant leaves the room at \a roomJid for the given \a reason. */
    Q_SIGNAL void participantLeft(const QString &roomJid, const QXmppMucParticipant &participant, QXmpp::Muc::LeaveReason reason);
    /*!
        Emitted when we are forcibly removed from the room at \a roomJid (kicked, banned, etc.)
        for the given \a reason.

        The room state is still accessible during this signal's emission.
        After all handlers return, the room state is cleaned up.
        The \a destroy parameter contains room destruction info if the reason is \c RoomDestroyed.
    */
    Q_SIGNAL void removedFromRoom(const QString &roomJid, QXmpp::Muc::LeaveReason reason, const std::optional<QXmpp::Muc::Destroy> &destroy);
    /*! Emitted with the \a messages received for the room at \a roomJid during joining. */
    Q_SIGNAL void roomHistoryReceived(const QString &roomJid, const QList<QXmppMessage> &messages);
    /*! Emitted when a groupchat \a message is received in the joined room at \a roomJid. */
    Q_SIGNAL void messageReceived(const QString &roomJid, const QXmppMessage &message);
    /*!
        Emitted when a voice \a request is received in the joined moderated room at \a roomJid.

        This signal is only emitted for moderators. The moderator can approve or
        deny the request by calling QXmppMucRoomV2::answerVoiceRequest().

        \since QXmpp 1.16
    */
    Q_SIGNAL void voiceRequestReceived(const QString &roomJid, const QXmppMucVoiceRequest &request);
    /*!
        Emitted when a mediated \a invite is received from the room at \a roomJid, protected by
        the given \a password (if any).

        The user is not yet in the room at this point. Call joinRoom() to accept
        or declineInvitation() to decline.

        \since QXmpp 1.16
    */
    Q_SIGNAL void invitationReceived(const QString &roomJid, const QXmpp::Muc::Invite &invite, const QString &password);
    /*!
        Emitted when the room at \a roomJid reports that an invitee declined an invitation via
        \a decline.

        \since QXmpp 1.16
    */
    Q_SIGNAL void invitationDeclined(const QString &roomJid, const QXmpp::Muc::Decline &decline);

    /*!
        Emitted when a \xep{0249}{Direct MUC Invitations} \a invitation is received.

        The \a from is the full JID of the user who sent the invitation, and \a message is the
        full message stanza it was received in.

        \since QXmpp 1.16
    */
    Q_SIGNAL void directInvitationReceived(const QXmpp::Muc::DirectInvitation &invitation, const QString &from, const QXmppMessage &message);

    bool handleMessage(const QXmppMessage &) override;

    QXmppTask<QXmpp::SendResult> declineInvitation(const QString &roomJid, QXmpp::Muc::Decline decline);

    QXmppTask<QXmpp::SendResult> sendDirectInvitation(const QString &to, QXmpp::Muc::DirectInvitation invitation, QXmppMessage message = {});

protected:
    void onRegistered(QXmppClient *client) override;
    void onUnregistered(QXmppClient *client) override;

private:
    void onConnected();
    void onDisconnected();

    QXmppTask<QXmpp::Result<QXmppMucRoomV2>> createRoomAtJid(const QString &roomJid, const QString &nickname);

    friend class QXmppMucManagerV2Private;
    friend class QXmppMucRoomV2;
    friend class QXmppMucParticipant;
    friend class tst_QXmppMuc;
    const std::unique_ptr<QXmppMucManagerV2Private> d;
};

/*!
    \class QXmppMucRoomV2
    \inmodule QXmpp

    \brief Handle to a \xep{0045}{Multi-User Chat} room. Copyable value type backed by a \c shared_ptr.

    A handle is obtained from QXmppMucManagerV2::joinRoom(), QXmppMucManagerV2::createRoom(), or
    QXmppMucManagerV2::findRoom(). It owns a strong reference to the underlying room state so its
    QBindable getters are always safe to read — the state lives as long as any handle does.

    \section1 Lifetime

    When you leave a room or are kicked, the manager drops its own reference but keeps a \c weak_ptr
    so that caller handles can continue to observe the final state as a frozen snapshot. Rejoining
    the same room while a handle is still held revives the existing state in place, preserving
    cached roomInfo, roomConfig, avatars, etc. When the last handle is dropped, memory is freed.

    \section1 Bindable properties

    Most observable state (subject(), nickname(), joined(), canSendMessages(), …) is exposed as
    \c QBindable<T>. You can connect them to QProperty observers or read them directly:

    \code
    auto canSend = room.canSendMessages();
    canSend.addNotifier([canSend]() {
        qDebug() << "canSendMessages changed:" << canSend.value();
    });
    \endcode

    \section1 Participants

    participants() returns a snapshot list of QXmppMucParticipant handles. Each participant handle
    likewise owns a strong reference to its participant data, so it is safe to hold across
    participants coming and going. Connect to QXmppMucManagerV2::participantJoined() and
    QXmppMucManagerV2::participantLeft() (or the convenience helpers onParticipantJoined() /
    onParticipantLeft()) to be notified of changes.

    \note QXmppMucManagerV2 itself must remain alive while handles are in use — the handles
    own the data but the manager owns the signal infrastructure. Accessing a handle after the
    manager is destroyed is undefined behavior.

    \warning THIS API IS NOT FINALIZED YET and may still change in incompatible ways
    before it is released.

    \since QXmpp 1.16
*/
class QXMPP_EXPORT QXmppMucRoomV2
{
public:
    QXmppMucRoomV2() = delete;
    QXmppMucRoomV2(const QXmppMucRoomV2 &) = default;
    QXmppMucRoomV2(QXmppMucRoomV2 &&) = default;
    QXmppMucRoomV2 &operator=(const QXmppMucRoomV2 &) = default;
    QXmppMucRoomV2 &operator=(QXmppMucRoomV2 &&) = default;

    QBindable<QString> subject() const;
    QBindable<QString> nickname() const;
    QBindable<bool> joined() const;
    QList<QXmppMucParticipant> participants() const;
    std::optional<QXmppMucParticipant> selfParticipant() const;

    QBindable<bool> canSendMessages() const;
    QBindable<bool> canChangeSubject() const;
    QBindable<bool> canSetRoles() const;
    QBindable<bool> canSetAffiliations() const;
    QBindable<bool> canConfigureRoom() const;
    QBindable<bool> isNonAnonymous() const;
    QBindable<bool> isPublic() const;
    QBindable<bool> isMembersOnly() const;
    QBindable<bool> isModerated() const;
    QBindable<bool> isPersistent() const;
    QBindable<bool> isPasswordProtected() const;
    QBindable<QString> description() const;
    QBindable<QString> language() const;
    QBindable<QStringList> contactJids() const;
    QBindable<std::optional<QXmppMucRoomInfo>> roomInfo() const;
    QBindable<std::optional<QXmppMucRoomConfig>> roomConfig() const;
    void setWatchRoomConfig(bool watch);
    bool isWatchingRoomConfig() const;

    QBindable<QStringList> avatarHashes() const;
    QBindable<std::optional<QXmpp::Muc::Avatar>> avatar() const;
    void setWatchAvatar(bool watch);
    bool isWatchingAvatar() const;
    QXmppTask<QXmpp::Result<>> setAvatar(std::optional<QXmpp::Muc::Avatar> avatar);

    QXmppTask<QXmpp::Result<>> sendMessage(QXmppMessage message);
    QXmppTask<QXmpp::SendResult> sendPrivateMessage(const QXmppMucParticipant &participant, QXmppMessage message);
    QXmppTask<QXmpp::Result<>> setSubject(const QString &subject);
    QXmppTask<QXmpp::Result<>> setNickname(const QString &newNick);
    QXmppTask<QXmpp::SendResult> setPresence(QXmppPresence presence);
    QXmppTask<QXmpp::Result<>> leave();

    QXmppTask<QXmpp::Result<>> setRole(const QXmppMucParticipant &participant, QXmpp::Muc::Role role, const QString &reason = {});
    QXmppTask<QXmpp::Result<>> setRoles(const QList<QXmpp::Muc::Item> &items);
    QXmppTask<QXmpp::Result<>> setAffiliation(const QString &jid, QXmpp::Muc::Affiliation affiliation, const QString &reason = {});
    QXmppTask<QXmpp::Result<>> setAffiliations(const QList<QXmpp::Muc::Item> &items);
    QXmppTask<QXmpp::Result<QList<QXmpp::Muc::Item>>> requestAffiliationList(QXmpp::Muc::Affiliation affiliation);
    QXmppTask<QXmpp::Result<QString>> requestReservedNickname();
    QXmppTask<QXmpp::Result<QXmppDataForm>> requestRegistrationForm();
    QXmppTask<QXmpp::Result<>> submitRegistration(const QXmppDataForm &form);

    QXmppTask<QXmpp::SendResult> requestVoice();
    QXmppTask<QXmpp::SendResult> answerVoiceRequest(const QXmppMucVoiceRequest &request, bool allow);
    QXmppTask<QXmpp::SendResult> inviteUser(QXmpp::Muc::Invite invite);

    QXmppTask<QXmpp::Result<QXmppMucRoomConfig>> requestRoomConfig(bool watch = false);
    QXmppTask<QXmpp::Result<>> setRoomConfig(const QXmppMucRoomConfig &config);
    QXmppTask<QXmpp::Result<>> cancelRoomCreation();
    QXmppTask<QXmpp::Result<>> destroyRoom(const QString &reason = {}, const QString &alternateJid = {});

    /*!
        Connects \a f to the participantJoined signal, filtered for this room, with the
        given \a context object.
    */
    template<typename Func>
    QMetaObject::Connection onParticipantJoined(QObject *context, Func &&f) const
    {
        auto *manager = this->manager();
        return QObject::connect(manager, &QXmppMucManagerV2::participantJoined, context, [jid = jid(), f = std::forward<Func>(f)](const QString &roomJid, const QXmppMucParticipant &participant) {
            if (roomJid == jid) {
                f(participant);
            }
        });
    }

    /*!
        Connects \a f to the participantLeft signal, filtered for this room, with the
        given \a context object.
    */
    template<typename Func>
    QMetaObject::Connection onParticipantLeft(QObject *context, Func &&f) const
    {
        auto *manager = this->manager();
        return QObject::connect(manager, &QXmppMucManagerV2::participantLeft, context, [jid = jid(), f = std::forward<Func>(f)](const QString &roomJid, const QXmppMucParticipant &participant, QXmpp::Muc::LeaveReason reason) {
            if (roomJid == jid) {
                f(participant, reason);
            }
        });
    }

    QString jid() const;
    QXmppMucManagerV2 *manager() const;

private:
    explicit QXmppMucRoomV2(std::shared_ptr<QXmpp::Private::MucRoomData> data)
        : m_data(std::move(data))
    {
    }

    friend class QXmppMucManagerV2;
    friend struct QXmppMucManagerV2Private;
    friend class tst_QXmppMuc;
    std::shared_ptr<QXmpp::Private::MucRoomData> m_data;
};

/*!
    \class QXmppMucParticipant
    \inmodule QXmpp

    \brief Lightweight handle to a participant in a \xep{0045}{Multi-User Chat} room.

    Each participant handle owns a strong reference to its participant data, so it is safe to
    hold across participants coming and going.

    \note QXmppMucManagerV2 must remain alive while participant handles are in use — the handles
    own the data but the manager owns the signal infrastructure. Accessing a handle after the
    manager is destroyed is undefined behavior.

    \warning THIS API IS NOT FINALIZED YET and may still change in incompatible ways
    before it is released.

    \since QXmpp 1.16
*/
class QXMPP_EXPORT QXmppMucParticipant
{
public:
    QXmppMucParticipant() = delete;
    QXmppMucParticipant(const QXmppMucParticipant &) = default;
    QXmppMucParticipant(QXmppMucParticipant &&) = default;
    QXmppMucParticipant &operator=(const QXmppMucParticipant &) = default;
    QXmppMucParticipant &operator=(QXmppMucParticipant &&) = default;

    /*! Returns the participant's nickname in the room. */
    QBindable<QString> nickname() const;
    /*! Returns the participant's real JID if known. */
    QBindable<QString> jid() const;
    /*! Returns the participant's role in the room. */
    QBindable<QXmpp::Muc::Role> role() const;
    /*! Returns the participant's affiliation with the room. */
    QBindable<QXmpp::Muc::Affiliation> affiliation() const;
    /*! Returns the participant's \xep{0421}{Occupant Id} if the room supports it. */
    QString occupantId() const;

private:
    explicit QXmppMucParticipant(std::shared_ptr<QXmpp::Private::MucParticipantData> data)
        : m_data(std::move(data))
    {
    }

    friend class QXmppMucManagerV2;
    friend struct QXmppMucManagerV2Private;
    friend class QXmppMucRoomV2;
    friend class tst_QXmppMuc;
    std::shared_ptr<QXmpp::Private::MucParticipantData> m_data;
};

#endif  // QXMPPMUCMANAGERV2_H
