// SPDX-FileCopyrightText: 2021 Nheko Contributors
//
// SPDX-License-Identifier: GPL-3.0-or-later

#include "TimelineModel.h"

#include <algorithm>
#include <thread>
#include <type_traits>

#include <QCache>
#include <QClipboard>
#include <QDesktopServices>
#include <QFileDialog>
#include <QGuiApplication>
#include <QMimeDatabase>
#include <QRegularExpression>
#include <QSettings>
#include <QStandardPaths>
#include <QVariant>

#include "Cache_p.h"
#include "ChatPage.h"
#include "Config.h"
#include "EventAccessors.h"
#include "Logging.h"
#include "MainWindow.h"
#include "MatrixClient.h"
#include "MemberList.h"
#include "MxcImageProvider.h"
#include "ReadReceiptsModel.h"
#include "TimelineViewManager.h"
#include "Utils.h"
#include "encryption/Olm.h"

Q_DECLARE_METATYPE(QModelIndex)

namespace std {
inline uint
qHash(const std::string &key, uint seed = 0)
{
    return qHash(QByteArray::fromRawData(key.data(), (int)key.length()), seed);
}
}

namespace {
struct RoomEventType
{
    template<class T>
    qml_mtx_events::EventType operator()(const mtx::events::Event<T> &e)
    {
        using mtx::events::EventType;
        switch (e.type) {
        case EventType::RoomKeyRequest:
            return qml_mtx_events::EventType::KeyRequest;
        case EventType::Reaction:
            return qml_mtx_events::EventType::Reaction;
        case EventType::RoomAliases:
            return qml_mtx_events::EventType::Aliases;
        case EventType::RoomAvatar:
            return qml_mtx_events::EventType::Avatar;
        case EventType::RoomCanonicalAlias:
            return qml_mtx_events::EventType::CanonicalAlias;
        case EventType::RoomCreate:
            return qml_mtx_events::EventType::RoomCreate;
        case EventType::RoomEncrypted:
            return qml_mtx_events::EventType::Encrypted;
        case EventType::RoomEncryption:
            return qml_mtx_events::EventType::Encryption;
        case EventType::RoomGuestAccess:
            return qml_mtx_events::EventType::RoomGuestAccess;
        case EventType::RoomHistoryVisibility:
            return qml_mtx_events::EventType::RoomHistoryVisibility;
        case EventType::RoomJoinRules:
            return qml_mtx_events::EventType::RoomJoinRules;
        case EventType::RoomMember:
            return qml_mtx_events::EventType::Member;
        case EventType::RoomMessage:
            return qml_mtx_events::EventType::UnknownMessage;
        case EventType::RoomName:
            return qml_mtx_events::EventType::Name;
        case EventType::RoomPowerLevels:
            return qml_mtx_events::EventType::PowerLevels;
        case EventType::RoomTopic:
            return qml_mtx_events::EventType::Topic;
        case EventType::RoomTombstone:
            return qml_mtx_events::EventType::Tombstone;
        case EventType::RoomRedaction:
            return qml_mtx_events::EventType::Redaction;
        case EventType::RoomPinnedEvents:
            return qml_mtx_events::EventType::PinnedEvents;
        case EventType::Sticker:
            return qml_mtx_events::EventType::Sticker;
        case EventType::Tag:
            return qml_mtx_events::EventType::Tag;
        case EventType::Unsupported:
            return qml_mtx_events::EventType::Unsupported;
        default:
            return qml_mtx_events::EventType::UnknownMessage;
        }
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::Audio> &)
    {
        return qml_mtx_events::EventType::AudioMessage;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::Emote> &)
    {
        return qml_mtx_events::EventType::EmoteMessage;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::File> &)
    {
        return qml_mtx_events::EventType::FileMessage;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::Image> &)
    {
        return qml_mtx_events::EventType::ImageMessage;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::Notice> &)
    {
        return qml_mtx_events::EventType::NoticeMessage;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::Text> &)
    {
        return qml_mtx_events::EventType::TextMessage;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::Video> &)
    {
        return qml_mtx_events::EventType::VideoMessage;
    }
    qml_mtx_events::EventType
    operator()(const mtx::events::Event<mtx::events::msg::KeyVerificationRequest> &)
    {
        return qml_mtx_events::EventType::KeyVerificationRequest;
    }
    qml_mtx_events::EventType
    operator()(const mtx::events::Event<mtx::events::msg::KeyVerificationStart> &)
    {
        return qml_mtx_events::EventType::KeyVerificationStart;
    }
    qml_mtx_events::EventType
    operator()(const mtx::events::Event<mtx::events::msg::KeyVerificationMac> &)
    {
        return qml_mtx_events::EventType::KeyVerificationMac;
    }
    qml_mtx_events::EventType
    operator()(const mtx::events::Event<mtx::events::msg::KeyVerificationAccept> &)
    {
        return qml_mtx_events::EventType::KeyVerificationAccept;
    }
    qml_mtx_events::EventType
    operator()(const mtx::events::Event<mtx::events::msg::KeyVerificationReady> &)
    {
        return qml_mtx_events::EventType::KeyVerificationReady;
    }
    qml_mtx_events::EventType
    operator()(const mtx::events::Event<mtx::events::msg::KeyVerificationCancel> &)
    {
        return qml_mtx_events::EventType::KeyVerificationCancel;
    }
    qml_mtx_events::EventType
    operator()(const mtx::events::Event<mtx::events::msg::KeyVerificationKey> &)
    {
        return qml_mtx_events::EventType::KeyVerificationKey;
    }
    qml_mtx_events::EventType
    operator()(const mtx::events::Event<mtx::events::msg::KeyVerificationDone> &)
    {
        return qml_mtx_events::EventType::KeyVerificationDone;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::Redacted> &)
    {
        return qml_mtx_events::EventType::Redacted;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::CallInvite> &)
    {
        return qml_mtx_events::EventType::CallInvite;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::CallAnswer> &)
    {
        return qml_mtx_events::EventType::CallAnswer;
    }
    qml_mtx_events::EventType operator()(const mtx::events::Event<mtx::events::msg::CallHangUp> &)
    {
        return qml_mtx_events::EventType::CallHangUp;
    }
    qml_mtx_events::EventType
    operator()(const mtx::events::Event<mtx::events::msg::CallCandidates> &)
    {
        return qml_mtx_events::EventType::CallCandidates;
    }
    // ::EventType::Type operator()(const Event<mtx::events::msg::Location> &e) { return
    // ::EventType::LocationMessage; }
};
}

qml_mtx_events::EventType
toRoomEventType(const mtx::events::collections::TimelineEvents &event)
{
    return std::visit(RoomEventType{}, event);
}

QString
toRoomEventTypeString(const mtx::events::collections::TimelineEvents &event)
{
    return std::visit([](const auto &e) { return QString::fromStdString(to_string(e.type)); },
                      event);
}

mtx::events::EventType
qml_mtx_events::fromRoomEventType(qml_mtx_events::EventType t)
{
    switch (t) {
    // Unsupported event
    case qml_mtx_events::Unsupported:
        return mtx::events::EventType::Unsupported;

    /// m.room_key_request
    case qml_mtx_events::KeyRequest:
        return mtx::events::EventType::RoomKeyRequest;
    /// m.reaction:
    case qml_mtx_events::Reaction:
        return mtx::events::EventType::Reaction;
    /// m.room.aliases
    case qml_mtx_events::Aliases:
        return mtx::events::EventType::RoomAliases;
    /// m.room.avatar
    case qml_mtx_events::Avatar:
        return mtx::events::EventType::RoomAvatar;
    /// m.call.invite
    case qml_mtx_events::CallInvite:
        return mtx::events::EventType::CallInvite;
    /// m.call.answer
    case qml_mtx_events::CallAnswer:
        return mtx::events::EventType::CallAnswer;
    /// m.call.hangup
    case qml_mtx_events::CallHangUp:
        return mtx::events::EventType::CallHangUp;
    /// m.call.candidates
    case qml_mtx_events::CallCandidates:
        return mtx::events::EventType::CallCandidates;
    /// m.room.canonical_alias
    case qml_mtx_events::CanonicalAlias:
        return mtx::events::EventType::RoomCanonicalAlias;
    /// m.room.create
    case qml_mtx_events::RoomCreate:
        return mtx::events::EventType::RoomCreate;
    /// m.room.encrypted.
    case qml_mtx_events::Encrypted:
        return mtx::events::EventType::RoomEncrypted;
    /// m.room.encryption.
    case qml_mtx_events::Encryption:
        return mtx::events::EventType::RoomEncryption;
    /// m.room.guest_access
    case qml_mtx_events::RoomGuestAccess:
        return mtx::events::EventType::RoomGuestAccess;
    /// m.room.history_visibility
    case qml_mtx_events::RoomHistoryVisibility:
        return mtx::events::EventType::RoomHistoryVisibility;
    /// m.room.join_rules
    case qml_mtx_events::RoomJoinRules:
        return mtx::events::EventType::RoomJoinRules;
    /// m.room.member
    case qml_mtx_events::Member:
        return mtx::events::EventType::RoomMember;
    /// m.room.name
    case qml_mtx_events::Name:
        return mtx::events::EventType::RoomName;
    /// m.room.power_levels
    case qml_mtx_events::PowerLevels:
        return mtx::events::EventType::RoomPowerLevels;
    /// m.room.tombstone
    case qml_mtx_events::Tombstone:
        return mtx::events::EventType::RoomTombstone;
    /// m.room.topic
    case qml_mtx_events::Topic:
        return mtx::events::EventType::RoomTopic;
    /// m.room.redaction
    case qml_mtx_events::Redaction:
        return mtx::events::EventType::RoomRedaction;
    /// m.room.pinned_events
    case qml_mtx_events::PinnedEvents:
        return mtx::events::EventType::RoomPinnedEvents;
    // m.sticker
    case qml_mtx_events::Sticker:
        return mtx::events::EventType::Sticker;
    // m.tag
    case qml_mtx_events::Tag:
        return mtx::events::EventType::Tag;
    /// m.room.message
    case qml_mtx_events::AudioMessage:
    case qml_mtx_events::EmoteMessage:
    case qml_mtx_events::FileMessage:
    case qml_mtx_events::ImageMessage:
    case qml_mtx_events::LocationMessage:
    case qml_mtx_events::NoticeMessage:
    case qml_mtx_events::TextMessage:
    case qml_mtx_events::VideoMessage:
    case qml_mtx_events::Redacted:
    case qml_mtx_events::UnknownMessage:
    case qml_mtx_events::KeyVerificationRequest:
    case qml_mtx_events::KeyVerificationStart:
    case qml_mtx_events::KeyVerificationMac:
    case qml_mtx_events::KeyVerificationAccept:
    case qml_mtx_events::KeyVerificationCancel:
    case qml_mtx_events::KeyVerificationKey:
    case qml_mtx_events::KeyVerificationDone:
    case qml_mtx_events::KeyVerificationReady:
        return mtx::events::EventType::RoomMessage;
        //! m.image_pack, currently im.ponies.room_emotes
    case qml_mtx_events::ImagePackInRoom:
        return mtx::events::EventType::ImagePackInRoom;
    //! m.image_pack, currently im.ponies.user_emotes
    case qml_mtx_events::ImagePackInAccountData:
        return mtx::events::EventType::ImagePackInAccountData;
    //! m.image_pack.rooms, currently im.ponies.emote_rooms
    case qml_mtx_events::ImagePackRooms:
        return mtx::events::EventType::ImagePackRooms;
    default:
        return mtx::events::EventType::Unsupported;
    };
}

TimelineModel::TimelineModel(TimelineViewManager *manager, QString room_id, QObject *parent)
  : QAbstractListModel(parent)
  , events(room_id.toStdString(), this)
  , room_id_(room_id)
  , manager_(manager)
  , permissions_{room_id}
{
    lastMessage_.timestamp = 0;

    if (auto create =
          cache::client()->getStateEvent<mtx::events::state::Create>(room_id.toStdString()))
        this->isSpace_ = create->content.type == mtx::events::state::room_type::space;
    this->isEncrypted_ = cache::isRoomEncrypted(room_id_.toStdString());

    // this connection will simplify adding the plainRoomNameChanged() signal everywhere that it
    // needs to be
    connect(this, &TimelineModel::roomNameChanged, this, &TimelineModel::plainRoomNameChanged);

    connect(
      this,
      &TimelineModel::redactionFailed,
      this,
      [](const QString &msg) { emit ChatPage::instance()->showNotification(msg); },
      Qt::QueuedConnection);

    connect(this, &TimelineModel::dataAtIdChanged, this, [this](QString id) {
        relatedEventCacheBuster++;

        auto idx = idToIndex(id);
        if (idx != -1) {
            auto pos = index(idx);
            nhlog::ui()->debug("data changed at {}", id.toStdString());
            emit dataChanged(pos, pos);
        } else {
            nhlog::ui()->debug("id not found {}", id.toStdString());
        }
    });

    connect(this,
            &TimelineModel::newMessageToSend,
            this,
            &TimelineModel::addPendingMessage,
            Qt::QueuedConnection);
    connect(this, &TimelineModel::addPendingMessageToStore, &events, &EventStore::addPending);

    connect(&events, &EventStore::dataChanged, this, [this](int from, int to) {
        relatedEventCacheBuster++;
        nhlog::ui()->debug(
          "data changed {} to {}", events.size() - to - 1, events.size() - from - 1);
        emit dataChanged(index(events.size() - to - 1, 0), index(events.size() - from - 1, 0));
    });

    connect(&events, &EventStore::beginInsertRows, this, [this](int from, int to) {
        int first = events.size() - to;
        int last  = events.size() - from;
        if (from >= events.size()) {
            int batch_size = to - from;
            first += batch_size;
            last += batch_size;
        } else {
            first -= 1;
            last -= 1;
        }
        nhlog::ui()->debug("begin insert from {} to {}", first, last);
        beginInsertRows(QModelIndex(), first, last);
    });
    connect(&events, &EventStore::endInsertRows, this, [this]() { endInsertRows(); });
    connect(&events, &EventStore::beginResetModel, this, [this]() { beginResetModel(); });
    connect(&events, &EventStore::endResetModel, this, [this]() { endResetModel(); });
    connect(&events, &EventStore::newEncryptedImage, this, &TimelineModel::newEncryptedImage);
    connect(&events, &EventStore::fetchedMore, this, [this]() { setPaginationInProgress(false); });
    connect(&events,
            &EventStore::startDMVerification,
            this,
            [this](mtx::events::RoomEvent<mtx::events::msg::KeyVerificationRequest> msg) {
                ChatPage::instance()->receivedRoomDeviceVerificationRequest(msg, this);
            });
    connect(&events, &EventStore::updateFlowEventId, this, [this](std::string event_id) {
        this->updateFlowEventId(event_id);
    });

    // When a message is sent, check if the current edit/reply relates to that message,
    // and update the event_id so that it points to the sent message and not the pending one.
    connect(
      &events, &EventStore::messageSent, this, [this](std::string txn_id, std::string event_id) {
          if (edit_.toStdString() == txn_id) {
              edit_ = QString::fromStdString(event_id);
              emit editChanged(edit_);
          }
          if (reply_.toStdString() == txn_id) {
              reply_ = QString::fromStdString(event_id);
              emit replyChanged(reply_);
          }
      });

    connect(
      manager_, &TimelineViewManager::initialSyncChanged, &events, &EventStore::enableKeyRequests);

    connect(this, &TimelineModel::encryptionChanged, this, &TimelineModel::trustlevelChanged);
    connect(this, &TimelineModel::roomMemberCountChanged, this, &TimelineModel::trustlevelChanged);
    connect(
      cache::client(), &Cache::verificationStatusChanged, this, &TimelineModel::trustlevelChanged);

    showEventTimer.callOnTimeout(this, &TimelineModel::scrollTimerEvent);
}

QHash<int, QByteArray>
TimelineModel::roleNames() const
{
    return {
      {Type, "type"},
      {TypeString, "typeString"},
      {IsOnlyEmoji, "isOnlyEmoji"},
      {Body, "body"},
      {FormattedBody, "formattedBody"},
      {PreviousMessageUserId, "previousMessageUserId"},
      {IsSender, "isSender"},
      {UserId, "userId"},
      {UserName, "userName"},
      {PreviousMessageDay, "previousMessageDay"},
      {Day, "day"},
      {Timestamp, "timestamp"},
      {Url, "url"},
      {ThumbnailUrl, "thumbnailUrl"},
      {Blurhash, "blurhash"},
      {Filename, "filename"},
      {Filesize, "filesize"},
      {MimeType, "mimetype"},
      {OriginalHeight, "originalHeight"},
      {OriginalWidth, "originalWidth"},
      {ProportionalHeight, "proportionalHeight"},
      {EventId, "eventId"},
      {State, "status"},
      {IsEdited, "isEdited"},
      {IsEditable, "isEditable"},
      {IsEncrypted, "isEncrypted"},
      {Trustlevel, "trustlevel"},
      {EncryptionError, "encryptionError"},
      {ReplyTo, "replyTo"},
      {Reactions, "reactions"},
      {RoomId, "roomId"},
      {RoomName, "roomName"},
      {RoomTopic, "roomTopic"},
      {CallType, "callType"},
      {Dump, "dump"},
      {RelatedEventCacheBuster, "relatedEventCacheBuster"},
    };
}
int
TimelineModel::rowCount(const QModelIndex &parent) const
{
    Q_UNUSED(parent);
    return this->events.size();
}

QVariantMap
TimelineModel::getDump(QString eventId, QString relatedTo) const
{
    if (auto event = events.get(eventId.toStdString(), relatedTo.toStdString()))
        return data(*event, Dump).toMap();
    return {};
}

QVariant
TimelineModel::data(const mtx::events::collections::TimelineEvents &event, int role) const
{
    using namespace mtx::accessors;
    namespace acc = mtx::accessors;

    switch (role) {
    case IsSender:
        return QVariant(acc::sender(event) == http::client()->user_id().to_string());
    case UserId:
        return QVariant(QString::fromStdString(acc::sender(event)));
    case UserName:
        return QVariant(displayName(QString::fromStdString(acc::sender(event))));

    case Day: {
        QDateTime prevDate = origin_server_ts(event);
        prevDate.setTime(QTime());
        return QVariant(prevDate.toMSecsSinceEpoch());
    }
    case Timestamp:
        return QVariant(origin_server_ts(event));
    case Type:
        return QVariant(toRoomEventType(event));
    case TypeString:
        return QVariant(toRoomEventTypeString(event));
    case IsOnlyEmoji: {
        QString qBody = QString::fromStdString(body(event));

        QVector<uint> utf32_string = qBody.toUcs4();
        int emojiCount             = 0;

        for (auto &code : utf32_string) {
            if (utils::codepointIsEmoji(code)) {
                emojiCount++;
            } else {
                return QVariant(0);
            }
        }

        return QVariant(emojiCount);
    }
    case Body:
        return QVariant(utils::replaceEmoji(QString::fromStdString(body(event)).toHtmlEscaped()));
    case FormattedBody: {
        const static QRegularExpression replyFallback(
          "<mx-reply>.*</mx-reply>", QRegularExpression::DotMatchesEverythingOption);

        auto ascent = QFontMetrics(UserSettings::instance()->font()).ascent();

        bool isReply = utils::isReply(event);

        auto formattedBody_ = QString::fromStdString(formatted_body(event));
        if (formattedBody_.isEmpty()) {
            auto body_ = QString::fromStdString(body(event));

            if (isReply) {
                while (body_.startsWith("> "))
                    body_ = body_.right(body_.size() - body_.indexOf('\n') - 1);
                if (body_.startsWith('\n'))
                    body_ = body_.right(body_.size() - 1);
            }
            formattedBody_ = body_.toHtmlEscaped().replace('\n', "<br>");
        } else {
            if (isReply)
                formattedBody_ = formattedBody_.remove(replyFallback);
        }

        // TODO(Nico): Don't parse html with a regex
        const static QRegularExpression matchImgUri("(<img [^>]*)src=\"mxc://([^\"]*)\"([^>]*>)");
        formattedBody_.replace(matchImgUri, "\\1 src=\"image://mxcImage/\\2\"\\3");
        // Same regex but for single quotes around the src
        const static QRegularExpression matchImgUri2("(<img [^>]*)src=\'mxc://([^\']*)\'([^>]*>)");
        formattedBody_.replace(matchImgUri2, "\\1 src=\"image://mxcImage/\\2\"\\3");
        const static QRegularExpression matchEmoticonHeight(
          "(<img data-mx-emoticon [^>]*)height=\"([^\"]*)\"([^>]*>)");
        formattedBody_.replace(matchEmoticonHeight, QString("\\1 height=\"%1\"\\3").arg(ascent));

        return QVariant(
          utils::replaceEmoji(utils::linkifyMessage(utils::escapeBlacklistedHtml(formattedBody_))));
    }
    case Url:
        return QVariant(QString::fromStdString(url(event)));
    case ThumbnailUrl:
        return QVariant(QString::fromStdString(thumbnail_url(event)));
    case Blurhash:
        return QVariant(QString::fromStdString(blurhash(event)));
    case Filename:
        return QVariant(QString::fromStdString(filename(event)));
    case Filesize:
        return QVariant(utils::humanReadableFileSize(filesize(event)));
    case MimeType:
        return QVariant(QString::fromStdString(mimetype(event)));
    case OriginalHeight:
        return QVariant(qulonglong{media_height(event)});
    case OriginalWidth:
        return QVariant(qulonglong{media_width(event)});
    case ProportionalHeight: {
        auto w = media_width(event);
        if (w == 0)
            w = 1;

        double prop = media_height(event) / (double)w;

        return QVariant(prop > 0 ? prop : 1.);
    }
    case EventId: {
        if (auto replaces = relations(event).replaces())
            return QVariant(QString::fromStdString(replaces.value()));
        else
            return QVariant(QString::fromStdString(event_id(event)));
    }
    case State: {
        auto id             = QString::fromStdString(event_id(event));
        auto containsOthers = [](const auto &vec) {
            for (const auto &e : vec)
                if (e.second != http::client()->user_id().to_string())
                    return true;
            return false;
        };

        // only show read receipts for messages not from us
        if (acc::sender(event) != http::client()->user_id().to_string())
            return qml_mtx_events::Empty;
        else if (!id.isEmpty() && id[0] == "m")
            return qml_mtx_events::Sent;
        else if (read.contains(id) || containsOthers(cache::readReceipts(id, room_id_)))
            return qml_mtx_events::Read;
        else
            return qml_mtx_events::Received;
    }
    case IsEdited:
        return QVariant(relations(event).replaces().has_value());
    case IsEditable:
        return QVariant(!is_state_event(event) &&
                        mtx::accessors::sender(event) == http::client()->user_id().to_string());
    case IsEncrypted: {
        auto id              = event_id(event);
        auto encrypted_event = events.get(id, "", false);
        return encrypted_event &&
               std::holds_alternative<mtx::events::EncryptedEvent<mtx::events::msg::Encrypted>>(
                 *encrypted_event);
    }

    case Trustlevel: {
        auto id              = event_id(event);
        auto encrypted_event = events.get(id, "", false);
        if (encrypted_event) {
            if (auto encrypted =
                  std::get_if<mtx::events::EncryptedEvent<mtx::events::msg::Encrypted>>(
                    &*encrypted_event)) {
                return olm::calculate_trust(
                  encrypted->sender,
                  MegolmSessionIndex(room_id_.toStdString(), encrypted->content));
            }
        }
        return crypto::Trust::Unverified;
    }

    case EncryptionError:
        return events.decryptionError(event_id(event));

    case ReplyTo:
        return QVariant(QString::fromStdString(relations(event).reply_to().value_or("")));
    case Reactions: {
        auto id = relations(event).replaces().value_or(event_id(event));
        return QVariant::fromValue(events.reactions(id));
    }
    case RoomId:
        return QVariant(room_id_);
    case RoomName:
        return QVariant(
          utils::replaceEmoji(QString::fromStdString(room_name(event)).toHtmlEscaped()));
    case RoomTopic:
        return QVariant(utils::replaceEmoji(utils::linkifyMessage(
          QString::fromStdString(room_topic(event)).toHtmlEscaped().replace("\n", "<br>"))));
    case CallType:
        return QVariant(QString::fromStdString(call_type(event)));
    case Dump: {
        QVariantMap m;
        auto names = roleNames();

        m.insert(names[Type], data(event, static_cast<int>(Type)));
        m.insert(names[TypeString], data(event, static_cast<int>(TypeString)));
        m.insert(names[IsOnlyEmoji], data(event, static_cast<int>(IsOnlyEmoji)));
        m.insert(names[Body], data(event, static_cast<int>(Body)));
        m.insert(names[FormattedBody], data(event, static_cast<int>(FormattedBody)));
        m.insert(names[IsSender], data(event, static_cast<int>(IsSender)));
        m.insert(names[UserId], data(event, static_cast<int>(UserId)));
        m.insert(names[UserName], data(event, static_cast<int>(UserName)));
        m.insert(names[Day], data(event, static_cast<int>(Day)));
        m.insert(names[Timestamp], data(event, static_cast<int>(Timestamp)));
        m.insert(names[Url], data(event, static_cast<int>(Url)));
        m.insert(names[ThumbnailUrl], data(event, static_cast<int>(ThumbnailUrl)));
        m.insert(names[Blurhash], data(event, static_cast<int>(Blurhash)));
        m.insert(names[Filename], data(event, static_cast<int>(Filename)));
        m.insert(names[Filesize], data(event, static_cast<int>(Filesize)));
        m.insert(names[MimeType], data(event, static_cast<int>(MimeType)));
        m.insert(names[OriginalHeight], data(event, static_cast<int>(OriginalHeight)));
        m.insert(names[OriginalWidth], data(event, static_cast<int>(OriginalWidth)));
        m.insert(names[ProportionalHeight], data(event, static_cast<int>(ProportionalHeight)));
        m.insert(names[EventId], data(event, static_cast<int>(EventId)));
        m.insert(names[State], data(event, static_cast<int>(State)));
        m.insert(names[IsEdited], data(event, static_cast<int>(IsEdited)));
        m.insert(names[IsEditable], data(event, static_cast<int>(IsEditable)));
        m.insert(names[IsEncrypted], data(event, static_cast<int>(IsEncrypted)));
        m.insert(names[ReplyTo], data(event, static_cast<int>(ReplyTo)));
        m.insert(names[RoomName], data(event, static_cast<int>(RoomName)));
        m.insert(names[RoomTopic], data(event, static_cast<int>(RoomTopic)));
        m.insert(names[CallType], data(event, static_cast<int>(CallType)));
        m.insert(names[EncryptionError], data(event, static_cast<int>(EncryptionError)));

        return QVariant(m);
    }
    case RelatedEventCacheBuster:
        return relatedEventCacheBuster;
    default:
        return QVariant();
    }
}

QVariant
TimelineModel::data(const QModelIndex &index, int role) const
{
    using namespace mtx::accessors;
    namespace acc = mtx::accessors;
    if (index.row() < 0 && index.row() >= rowCount())
        return QVariant();

    // HACK(Nico): fetchMore likes to break with dynamically sized delegates and reuseItems
    if (index.row() + 1 == rowCount() && !m_paginationInProgress)
        const_cast<TimelineModel *>(this)->fetchMore(index);

    auto event = events.get(rowCount() - index.row() - 1);

    if (!event)
        return "";

    if (role == PreviousMessageDay || role == PreviousMessageUserId) {
        int prevIdx = rowCount() - index.row() - 2;
        if (prevIdx < 0)
            return QVariant();
        auto tempEv = events.get(prevIdx);
        if (!tempEv)
            return QVariant();
        if (role == PreviousMessageUserId)
            return data(*tempEv, UserId);
        else
            return data(*tempEv, Day);
    }

    return data(*event, role);
}

QVariant
TimelineModel::dataById(QString id, int role, QString relatedTo)
{
    if (auto event = events.get(id.toStdString(), relatedTo.toStdString()))
        return data(*event, role);
    return QVariant();
}

bool
TimelineModel::canFetchMore(const QModelIndex &) const
{
    if (!events.size())
        return true;
    if (auto first = events.get(0);
        first &&
        !std::holds_alternative<mtx::events::StateEvent<mtx::events::state::Create>>(*first))
        return true;
    else

        return false;
}

void
TimelineModel::setPaginationInProgress(const bool paginationInProgress)
{
    if (m_paginationInProgress == paginationInProgress) {
        return;
    }

    m_paginationInProgress = paginationInProgress;
    emit paginationInProgressChanged(m_paginationInProgress);
}

void
TimelineModel::fetchMore(const QModelIndex &)
{
    if (m_paginationInProgress) {
        nhlog::ui()->warn("Already loading older messages");
        return;
    }

    setPaginationInProgress(true);

    events.fetchMore();
}

void
TimelineModel::sync(const mtx::responses::JoinedRoom &room)
{
    this->syncState(room.state);
    this->addEvents(room.timeline);

    if (room.unread_notifications.highlight_count != highlight_count ||
        room.unread_notifications.notification_count != notification_count) {
        notification_count = room.unread_notifications.notification_count;
        highlight_count    = room.unread_notifications.highlight_count;
        emit notificationsChanged();
    }
}

void
TimelineModel::syncState(const mtx::responses::State &s)
{
    using namespace mtx::events;

    for (const auto &e : s.events) {
        if (std::holds_alternative<StateEvent<state::Avatar>>(e))
            emit roomAvatarUrlChanged();
        else if (std::holds_alternative<StateEvent<state::Name>>(e))
            emit roomNameChanged();
        else if (std::holds_alternative<StateEvent<state::Topic>>(e))
            emit roomTopicChanged();
        else if (std::holds_alternative<StateEvent<state::Topic>>(e)) {
            permissions_.invalidate();
            emit permissionsChanged();
        } else if (std::holds_alternative<StateEvent<state::Member>>(e)) {
            emit roomAvatarUrlChanged();
            emit roomNameChanged();
            emit roomMemberCountChanged();

            if (roomMemberCount() <= 2) {
                emit isDirectChanged();
                emit directChatOtherUserIdChanged();
            }
        } else if (std::holds_alternative<StateEvent<state::Encryption>>(e)) {
            this->isEncrypted_ = cache::isRoomEncrypted(room_id_.toStdString());
            emit encryptionChanged();
        }
    }
}

void
TimelineModel::addEvents(const mtx::responses::Timeline &timeline)
{
    if (timeline.events.empty())
        return;

    events.handleSync(timeline);

    using namespace mtx::events;

    for (auto e : timeline.events) {
        if (auto encryptedEvent = std::get_if<EncryptedEvent<msg::Encrypted>>(&e)) {
            MegolmSessionIndex index(room_id_.toStdString(), encryptedEvent->content);

            auto result = olm::decryptEvent(index, *encryptedEvent);
            if (result.event)
                e = result.event.value();
        }

        if (std::holds_alternative<RoomEvent<msg::CallCandidates>>(e) ||
            std::holds_alternative<RoomEvent<msg::CallInvite>>(e) ||
            std::holds_alternative<RoomEvent<msg::CallAnswer>>(e) ||
            std::holds_alternative<RoomEvent<msg::CallHangUp>>(e))
            std::visit(
              [this](auto &event) {
                  event.room_id = room_id_.toStdString();
                  if constexpr (std::is_same_v<std::decay_t<decltype(event)>,
                                               RoomEvent<msg::CallAnswer>> ||
                                std::is_same_v<std::decay_t<decltype(event)>,
                                               RoomEvent<msg::CallHangUp>>)
                      emit newCallEvent(event);
                  else {
                      if (event.sender != http::client()->user_id().to_string())
                          emit newCallEvent(event);
                  }
              },
              e);
        else if (std::holds_alternative<StateEvent<state::Avatar>>(e))
            emit roomAvatarUrlChanged();
        else if (std::holds_alternative<StateEvent<state::Name>>(e))
            emit roomNameChanged();
        else if (std::holds_alternative<StateEvent<state::Topic>>(e))
            emit roomTopicChanged();
        else if (std::holds_alternative<StateEvent<state::PowerLevels>>(e)) {
            permissions_.invalidate();
            emit permissionsChanged();
        } else if (std::holds_alternative<StateEvent<state::Member>>(e)) {
            emit roomAvatarUrlChanged();
            emit roomNameChanged();
            emit roomMemberCountChanged();
        } else if (std::holds_alternative<StateEvent<state::Encryption>>(e)) {
            this->isEncrypted_ = cache::isRoomEncrypted(room_id_.toStdString());
            emit encryptionChanged();
        }
    }
    updateLastMessage();
}

template<typename T>
auto
isMessage(const mtx::events::RoomEvent<T> &e)
  -> std::enable_if_t<std::is_same<decltype(e.content.msgtype), std::string>::value, bool>
{
    return true;
}

template<typename T>
auto
isMessage(const mtx::events::Event<T> &)
{
    return false;
}

template<typename T>
auto
isMessage(const mtx::events::EncryptedEvent<T> &)
{
    return true;
}

auto
isMessage(const mtx::events::RoomEvent<mtx::events::msg::CallInvite> &)
{
    return true;
}

auto
isMessage(const mtx::events::RoomEvent<mtx::events::msg::CallAnswer> &)
{
    return true;
}
auto
isMessage(const mtx::events::RoomEvent<mtx::events::msg::CallHangUp> &)
{
    return true;
}

// Workaround. We also want to see a room at the top, if we just joined it
auto
isYourJoin(const mtx::events::StateEvent<mtx::events::state::Member> &e)
{
    return e.content.membership == mtx::events::state::Membership::Join &&
           e.state_key == http::client()->user_id().to_string();
}
template<typename T>
auto
isYourJoin(const mtx::events::Event<T> &)
{
    return false;
}

void
TimelineModel::updateLastMessage()
{
    for (auto it = events.size() - 1; it >= 0; --it) {
        auto event = events.get(it, decryptDescription);
        if (!event)
            continue;

        if (std::visit([](const auto &e) -> bool { return isYourJoin(e); }, *event)) {
            auto time   = mtx::accessors::origin_server_ts(*event);
            uint64_t ts = time.toMSecsSinceEpoch();
            auto description =
              DescInfo{QString::fromStdString(mtx::accessors::event_id(*event)),
                       QString::fromStdString(http::client()->user_id().to_string()),
                       tr("You joined this room."),
                       utils::descriptiveTime(time),
                       ts,
                       time};
            if (description != lastMessage_) {
                lastMessage_ = description;
                emit lastMessageChanged();
            }
            return;
        }
        if (!std::visit([](const auto &e) -> bool { return isMessage(e); }, *event))
            continue;

        auto description = utils::getMessageDescription(
          *event,
          QString::fromStdString(http::client()->user_id().to_string()),
          cache::displayName(room_id_, QString::fromStdString(mtx::accessors::sender(*event))));
        if (description != lastMessage_) {
            lastMessage_ = description;
            emit lastMessageChanged();
        }
        return;
    }
}

void
TimelineModel::setCurrentIndex(int index)
{
    auto oldIndex = idToIndex(currentId);
    currentId     = indexToId(index);
    if (index != oldIndex)
        emit currentIndexChanged(index);

    if (!ChatPage::instance()->isActiveWindow())
        return;

    if (!currentId.startsWith("m")) {
        auto oldReadIndex =
          cache::getEventIndex(roomId().toStdString(), currentReadId.toStdString());
        auto nextEventIndexAndId =
          cache::lastInvisibleEventAfter(roomId().toStdString(), currentId.toStdString());

        if (nextEventIndexAndId && (!oldReadIndex || *oldReadIndex < nextEventIndexAndId->first)) {
            readEvent(nextEventIndexAndId->second);
            currentReadId = QString::fromStdString(nextEventIndexAndId->second);
        }
    }
}

void
TimelineModel::readEvent(const std::string &id)
{
    http::client()->read_event(room_id_.toStdString(), id, [this](mtx::http::RequestErr err) {
        if (err) {
            nhlog::net()->warn(
              "failed to read_event ({}, {})", room_id_.toStdString(), currentId.toStdString());
        }
    });
}

QString
TimelineModel::displayName(QString id) const
{
    return cache::displayName(room_id_, id).toHtmlEscaped();
}

QString
TimelineModel::avatarUrl(QString id) const
{
    return cache::avatarUrl(room_id_, id);
}

QString
TimelineModel::formatDateSeparator(QDate date) const
{
    auto now = QDateTime::currentDateTime();

    QString fmt = QLocale::system().dateFormat(QLocale::LongFormat);

    if (now.date().year() == date.year()) {
        QRegularExpression rx("[^a-zA-Z]*y+[^a-zA-Z]*");
        fmt = fmt.remove(rx);
    }

    return date.toString(fmt);
}

void
TimelineModel::viewRawMessage(QString id)
{
    auto e = events.get(id.toStdString(), "", false);
    if (!e)
        return;
    std::string ev = mtx::accessors::serialize_event(*e).dump(4);
    emit showRawMessageDialog(QString::fromStdString(ev));
}

void
TimelineModel::forwardMessage(QString eventId, QString roomId)
{
    auto e = events.get(eventId.toStdString(), "");
    if (!e)
        return;

    emit forwardToRoom(e, roomId);
}

void
TimelineModel::viewDecryptedRawMessage(QString id)
{
    auto e = events.get(id.toStdString(), "");
    if (!e)
        return;

    std::string ev = mtx::accessors::serialize_event(*e).dump(4);
    emit showRawMessageDialog(QString::fromStdString(ev));
}

void
TimelineModel::openUserProfile(QString userid)
{
    UserProfile *userProfile = new UserProfile(room_id_, userid, manager_, this);
    connect(this, &TimelineModel::roomAvatarUrlChanged, userProfile, &UserProfile::updateAvatarUrl);
    emit manager_->openProfile(userProfile);
}

void
TimelineModel::replyAction(QString id)
{
    setReply(id);
}

void
TimelineModel::editAction(QString id)
{
    setEdit(id);
}

RelatedInfo
TimelineModel::relatedInfo(QString id)
{
    auto event = events.get(id.toStdString(), "");
    if (!event)
        return {};

    return utils::stripReplyFallbacks(*event, id.toStdString(), room_id_);
}

void
TimelineModel::showReadReceipts(QString id)
{
    emit openReadReceiptsDialog(new ReadReceiptsProxy{id, roomId(), this});
}

void
TimelineModel::redactEvent(QString id)
{
    if (!id.isEmpty()) {
        auto edits = events.edits(id.toStdString());
        http::client()->redact_event(
          room_id_.toStdString(),
          id.toStdString(),
          [this, id](const mtx::responses::EventId &, mtx::http::RequestErr err) {
              if (err) {
                  emit redactionFailed(tr("Message redaction failed: %1")
                                         .arg(QString::fromStdString(err->matrix_error.error)));
                  return;
              }

              emit dataAtIdChanged(id);
          });

        // redact all edits to prevent leaks
        for (const auto &e : edits) {
            auto id_ = mtx::accessors::event_id(e);
            http::client()->redact_event(
              room_id_.toStdString(),
              id_,
              [this, id, id_](const mtx::responses::EventId &, mtx::http::RequestErr err) {
                  if (err) {
                      emit redactionFailed(tr("Message redaction failed: %1")
                                             .arg(QString::fromStdString(err->matrix_error.error)));
                      return;
                  }

                  emit dataAtIdChanged(id);
              });
        }
    }
}

int
TimelineModel::idToIndex(QString id) const
{
    if (id.isEmpty())
        return -1;

    auto idx = events.idToIndex(id.toStdString());
    if (idx)
        return events.size() - *idx - 1;
    else
        return -1;
}

QString
TimelineModel::indexToId(int index) const
{
    auto id = events.indexToId(events.size() - index - 1);
    return id ? QString::fromStdString(*id) : "";
}

// Note: this will only be called for our messages
void
TimelineModel::markEventsAsRead(const std::vector<QString> &event_ids)
{
    for (const auto &id : event_ids) {
        read.insert(id);
        int idx = idToIndex(id);
        if (idx < 0) {
            return;
        }
        emit dataChanged(index(idx, 0), index(idx, 0));
    }
}

template<typename T>
void
TimelineModel::sendEncryptedMessage(mtx::events::RoomEvent<T> msg, mtx::events::EventType eventType)
{
    const auto room_id = room_id_.toStdString();

    using namespace mtx::events;
    using namespace mtx::identifiers;

    json doc = {{"type", mtx::events::to_string(eventType)},
                {"content", json(msg.content)},
                {"room_id", room_id}};

    try {
        mtx::events::EncryptedEvent<mtx::events::msg::Encrypted> event;
        event.content  = olm::encrypt_group_message(room_id, http::client()->device_id(), doc);
        event.event_id = msg.event_id;
        event.room_id  = room_id;
        event.sender   = http::client()->user_id().to_string();
        event.type     = mtx::events::EventType::RoomEncrypted;
        event.origin_server_ts = QDateTime::currentMSecsSinceEpoch();

        emit this->addPendingMessageToStore(event);

        // TODO: Let the user know about the errors.
    } catch (const lmdb::error &e) {
        nhlog::db()->critical("failed to open outbound megolm session ({}): {}", room_id, e.what());
        emit ChatPage::instance()->showNotification(
          tr("Failed to encrypt event, sending aborted!"));
    } catch (const mtx::crypto::olm_exception &e) {
        nhlog::crypto()->critical(
          "failed to open outbound megolm session ({}): {}", room_id, e.what());
        emit ChatPage::instance()->showNotification(
          tr("Failed to encrypt event, sending aborted!"));
    }
}

struct SendMessageVisitor
{
    explicit SendMessageVisitor(TimelineModel *model)
      : model_(model)
    {}

    template<typename T, mtx::events::EventType Event>
    void sendRoomEvent(mtx::events::RoomEvent<T> msg)
    {
        if (cache::isRoomEncrypted(model_->room_id_.toStdString())) {
            auto encInfo = mtx::accessors::file(msg);
            if (encInfo)
                emit model_->newEncryptedImage(encInfo.value());

            model_->sendEncryptedMessage(msg, Event);
        } else {
            msg.type = Event;
            emit model_->addPendingMessageToStore(msg);
        }
    }

    // Do-nothing operator for all unhandled events
    template<typename T>
    void operator()(const mtx::events::Event<T> &)
    {}

    // Operator for m.room.message events that contain a msgtype in their content
    template<typename T,
             std::enable_if_t<std::is_same<decltype(T::msgtype), std::string>::value, int> = 0>
    void operator()(mtx::events::RoomEvent<T> msg)
    {
        sendRoomEvent<T, mtx::events::EventType::RoomMessage>(msg);
    }

    // Special operator for reactions, which are a type of m.room.message, but need to be
    // handled distinctly for their differences from normal room messages.  Specifically,
    // reactions need to have the relation outside of ciphertext, or synapse / the homeserver
    // cannot handle it correctly.  See the MSC for more details:
    // https://github.com/matrix-org/matrix-doc/blob/matthew/msc1849/proposals/1849-aggregations.md#end-to-end-encryption
    void operator()(mtx::events::RoomEvent<mtx::events::msg::Reaction> msg)
    {
        msg.type = mtx::events::EventType::Reaction;
        emit model_->addPendingMessageToStore(msg);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::CallInvite> &event)
    {
        sendRoomEvent<mtx::events::msg::CallInvite, mtx::events::EventType::CallInvite>(event);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::CallCandidates> &event)
    {
        sendRoomEvent<mtx::events::msg::CallCandidates, mtx::events::EventType::CallCandidates>(
          event);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::CallAnswer> &event)
    {
        sendRoomEvent<mtx::events::msg::CallAnswer, mtx::events::EventType::CallAnswer>(event);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::CallHangUp> &event)
    {
        sendRoomEvent<mtx::events::msg::CallHangUp, mtx::events::EventType::CallHangUp>(event);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::KeyVerificationRequest> &msg)
    {
        sendRoomEvent<mtx::events::msg::KeyVerificationRequest,
                      mtx::events::EventType::RoomMessage>(msg);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::KeyVerificationReady> &msg)
    {
        sendRoomEvent<mtx::events::msg::KeyVerificationReady,
                      mtx::events::EventType::KeyVerificationReady>(msg);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::KeyVerificationStart> &msg)
    {
        sendRoomEvent<mtx::events::msg::KeyVerificationStart,
                      mtx::events::EventType::KeyVerificationStart>(msg);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::KeyVerificationAccept> &msg)
    {
        sendRoomEvent<mtx::events::msg::KeyVerificationAccept,
                      mtx::events::EventType::KeyVerificationAccept>(msg);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::KeyVerificationMac> &msg)
    {
        sendRoomEvent<mtx::events::msg::KeyVerificationMac,
                      mtx::events::EventType::KeyVerificationMac>(msg);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::KeyVerificationKey> &msg)
    {
        sendRoomEvent<mtx::events::msg::KeyVerificationKey,
                      mtx::events::EventType::KeyVerificationKey>(msg);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::KeyVerificationDone> &msg)
    {
        sendRoomEvent<mtx::events::msg::KeyVerificationDone,
                      mtx::events::EventType::KeyVerificationDone>(msg);
    }

    void operator()(const mtx::events::RoomEvent<mtx::events::msg::KeyVerificationCancel> &msg)
    {
        sendRoomEvent<mtx::events::msg::KeyVerificationCancel,
                      mtx::events::EventType::KeyVerificationCancel>(msg);
    }
    void operator()(mtx::events::Sticker msg)
    {
        msg.type = mtx::events::EventType::Sticker;
        if (cache::isRoomEncrypted(model_->room_id_.toStdString())) {
            model_->sendEncryptedMessage(msg, mtx::events::EventType::Sticker);
        } else
            emit model_->addPendingMessageToStore(msg);
    }

    TimelineModel *model_;
};

void
TimelineModel::addPendingMessage(mtx::events::collections::TimelineEvents event)
{
    std::visit(
      [](auto &msg) {
          // gets overwritten for reactions and stickers in SendMessageVisitor
          msg.type             = mtx::events::EventType::RoomMessage;
          msg.event_id         = "m" + http::client()->generate_txn_id();
          msg.sender           = http::client()->user_id().to_string();
          msg.origin_server_ts = QDateTime::currentMSecsSinceEpoch();
      },
      event);

    std::visit(SendMessageVisitor{this}, event);
}

void
TimelineModel::openMedia(QString eventId)
{
    cacheMedia(eventId,
               [](QString filename) { QDesktopServices::openUrl(QUrl::fromLocalFile(filename)); });
}

bool
TimelineModel::saveMedia(QString eventId) const
{
    mtx::events::collections::TimelineEvents *event = events.get(eventId.toStdString(), "");
    if (!event)
        return false;

    QString mxcUrl           = QString::fromStdString(mtx::accessors::url(*event));
    QString originalFilename = QString::fromStdString(mtx::accessors::filename(*event));
    QString mimeType         = QString::fromStdString(mtx::accessors::mimetype(*event));

    auto encryptionInfo = mtx::accessors::file(*event);

    qml_mtx_events::EventType eventType = toRoomEventType(*event);

    QString dialogTitle;
    if (eventType == qml_mtx_events::EventType::ImageMessage) {
        dialogTitle = tr("Save image");
    } else if (eventType == qml_mtx_events::EventType::VideoMessage) {
        dialogTitle = tr("Save video");
    } else if (eventType == qml_mtx_events::EventType::AudioMessage) {
        dialogTitle = tr("Save audio");
    } else {
        dialogTitle = tr("Save file");
    }

    const QString filterString = QMimeDatabase().mimeTypeForName(mimeType).filterString();
    const QString downloadsFolder =
      QStandardPaths::writableLocation(QStandardPaths::DownloadLocation);
    const QString openLocation = downloadsFolder + "/" + originalFilename;

    const QString filename =
      QFileDialog::getSaveFileName(manager_->getWidget(), dialogTitle, openLocation, filterString);

    if (filename.isEmpty())
        return false;

    const auto url = mxcUrl.toStdString();

    http::client()->download(url,
                             [filename, url, encryptionInfo](const std::string &data,
                                                             const std::string &,
                                                             const std::string &,
                                                             mtx::http::RequestErr err) {
                                 if (err) {
                                     nhlog::net()->warn("failed to retrieve image {}: {} {}",
                                                        url,
                                                        err->matrix_error.error,
                                                        static_cast<int>(err->status_code));
                                     return;
                                 }

                                 try {
                                     auto temp = data;
                                     if (encryptionInfo)
                                         temp = mtx::crypto::to_string(
                                           mtx::crypto::decrypt_file(temp, encryptionInfo.value()));

                                     QFile file(filename);

                                     if (!file.open(QIODevice::WriteOnly))
                                         return;

                                     file.write(QByteArray(temp.data(), (int)temp.size()));
                                     file.close();

                                     return;
                                 } catch (const std::exception &e) {
                                     nhlog::ui()->warn("Error while saving file to: {}", e.what());
                                 }
                             });
    return true;
}

void
TimelineModel::cacheMedia(QString eventId, std::function<void(const QString)> callback)
{
    mtx::events::collections::TimelineEvents *event = events.get(eventId.toStdString(), "");
    if (!event)
        return;

    QString mxcUrl           = QString::fromStdString(mtx::accessors::url(*event));
    QString originalFilename = QString::fromStdString(mtx::accessors::filename(*event));
    QString mimeType         = QString::fromStdString(mtx::accessors::mimetype(*event));

    auto encryptionInfo = mtx::accessors::file(*event);

    // If the message is a link to a non mxcUrl, don't download it
    if (!mxcUrl.startsWith("mxc://")) {
        emit mediaCached(mxcUrl, mxcUrl);
        return;
    }

    QString suffix = QMimeDatabase().mimeTypeForName(mimeType).preferredSuffix();

    const auto url  = mxcUrl.toStdString();
    const auto name = QString(mxcUrl).remove("mxc://");
    QFileInfo filename(QString("%1/media_cache/%2.%3")
                         .arg(QStandardPaths::writableLocation(QStandardPaths::CacheLocation))
                         .arg(name)
                         .arg(suffix));
    if (QDir::cleanPath(name) != name) {
        nhlog::net()->warn("mxcUrl '{}' is not safe, not downloading file", url);
        return;
    }

    QDir().mkpath(filename.path());

    if (filename.isReadable()) {
#if defined(Q_OS_WIN)
        emit mediaCached(mxcUrl, filename.filePath());
#else
        emit mediaCached(mxcUrl, "file://" + filename.filePath());
#endif
        if (callback) {
            callback(filename.filePath());
        }
        return;
    }

    http::client()->download(
      url,
      [this, callback, mxcUrl, filename, url, encryptionInfo](const std::string &data,
                                                              const std::string &,
                                                              const std::string &,
                                                              mtx::http::RequestErr err) {
          if (err) {
              nhlog::net()->warn("failed to retrieve image {}: {} {}",
                                 url,
                                 err->matrix_error.error,
                                 static_cast<int>(err->status_code));
              return;
          }

          try {
              auto temp = data;
              if (encryptionInfo)
                  temp =
                    mtx::crypto::to_string(mtx::crypto::decrypt_file(temp, encryptionInfo.value()));

              QFile file(filename.filePath());

              if (!file.open(QIODevice::WriteOnly))
                  return;

              file.write(QByteArray(temp.data(), (int)temp.size()));
              file.close();

              if (callback) {
                  callback(filename.filePath());
              }
          } catch (const std::exception &e) {
              nhlog::ui()->warn("Error while saving file to: {}", e.what());
          }

#if defined(Q_OS_WIN)
          emit mediaCached(mxcUrl, filename.filePath());
#else
          emit mediaCached(mxcUrl, "file://" + filename.filePath());
#endif
      });
}

void
TimelineModel::cacheMedia(QString eventId)
{
    cacheMedia(eventId, NULL);
}

void
TimelineModel::showEvent(QString eventId)
{
    using namespace std::chrono_literals;
    // Direct to eventId
    if (eventId[0] == '$') {
        int idx = idToIndex(eventId);
        if (idx == -1) {
            nhlog::ui()->warn("Scrolling to event id {}, failed - no known index",
                              eventId.toStdString());
            return;
        }
        eventIdToShow = eventId;
        emit scrollTargetChanged();
        showEventTimer.start(50ms);
        return;
    }
    // to message index
    eventId       = indexToId(eventId.toInt());
    eventIdToShow = eventId;
    emit scrollTargetChanged();
    showEventTimer.start(50ms);
    return;
}

void
TimelineModel::eventShown()
{
    eventIdToShow.clear();
    emit scrollTargetChanged();
}

QString
TimelineModel::scrollTarget() const
{
    return eventIdToShow;
}

void
TimelineModel::scrollTimerEvent()
{
    if (eventIdToShow.isEmpty() || showEventTimerCounter > 3) {
        showEventTimer.stop();
        showEventTimerCounter = 0;
    } else {
        emit scrollToIndex(idToIndex(eventIdToShow));
        showEventTimerCounter++;
    }
}

void
TimelineModel::requestKeyForEvent(QString id)
{
    auto encrypted_event = events.get(id.toStdString(), "", false);
    if (encrypted_event) {
        if (auto ev = std::get_if<mtx::events::EncryptedEvent<mtx::events::msg::Encrypted>>(
              encrypted_event))
            events.requestSession(*ev, true);
    }
}

void
TimelineModel::copyLinkToEvent(QString eventId) const
{
    QStringList vias;

    auto alias = cache::client()->getRoomAliases(room_id_.toStdString());
    QString room;
    if (alias) {
        room = QString::fromStdString(alias->alias);
        if (room.isEmpty() && !alias->alt_aliases.empty()) {
            room = QString::fromStdString(alias->alt_aliases.front());
        }
    }

    if (room.isEmpty())
        room = room_id_;

    vias.push_back(QString("via=%1").arg(QString(
      QUrl::toPercentEncoding(QString::fromStdString(http::client()->user_id().hostname())))));
    auto members = cache::getMembers(room_id_.toStdString(), 0, 100);
    for (const auto &m : members) {
        if (vias.size() >= 4)
            break;

        auto user_id   = mtx::identifiers::parse<mtx::identifiers::User>(m.user_id.toStdString());
        QString server = QString("via=%1").arg(
          QString(QUrl::toPercentEncoding(QString::fromStdString(user_id.hostname()))));

        if (!vias.contains(server))
            vias.push_back(server);
    }

    auto link = QString("https://matrix.to/#/%1/%2?%3")
                  .arg(QString(QUrl::toPercentEncoding(room)),
                       QString(QUrl::toPercentEncoding(eventId)),
                       vias.join('&'));

    QGuiApplication::clipboard()->setText(link);
}

QString
TimelineModel::formatTypingUsers(const std::vector<QString> &users, QColor bg)
{
    QString temp =
      tr("%1 and %2 are typing.",
         "Multiple users are typing. First argument is a comma separated list of potentially "
         "multiple users. Second argument is the last user of that list. (If only one user is "
         "typing, %1 is empty. You should still use it in your string though to silence Qt "
         "warnings.)",
         (int)users.size());

    if (users.empty()) {
        return "";
    }

    QStringList uidWithoutLast;

    auto formatUser = [this, bg](const QString &user_id) -> QString {
        auto uncoloredUsername = utils::replaceEmoji(displayName(user_id));
        QString prefix =
          QString("<font color=\"%1\">").arg(manager_->userColor(user_id, bg).name());

        // color only parts that don't have a font already specified
        QString coloredUsername;
        int index = 0;
        do {
            auto startIndex = uncoloredUsername.indexOf("<font", index);

            if (startIndex - index != 0)
                coloredUsername +=
                  prefix +
                  uncoloredUsername.midRef(index, startIndex > 0 ? startIndex - index : -1) +
                  "</font>";

            auto endIndex = uncoloredUsername.indexOf("</font>", startIndex);
            if (endIndex > 0)
                endIndex += sizeof("</font>") - 1;

            if (endIndex - startIndex != 0)
                coloredUsername += uncoloredUsername.midRef(startIndex, endIndex - startIndex);

            index = endIndex;
        } while (index > 0 && index < uncoloredUsername.size());

        return coloredUsername;
    };

    for (size_t i = 0; i + 1 < users.size(); i++) {
        uidWithoutLast.append(formatUser(users[i]));
    }

    return temp.arg(uidWithoutLast.join(", ")).arg(formatUser(users.back()));
}

QString
TimelineModel::formatJoinRuleEvent(QString id)
{
    mtx::events::collections::TimelineEvents *e = events.get(id.toStdString(), "");
    if (!e)
        return "";

    auto event = std::get_if<mtx::events::StateEvent<mtx::events::state::JoinRules>>(e);
    if (!event)
        return "";

    QString user = QString::fromStdString(event->sender);
    QString name = utils::replaceEmoji(displayName(user));

    switch (event->content.join_rule) {
    case mtx::events::state::JoinRule::Public:
        return tr("%1 opened the room to the public.").arg(name);
    case mtx::events::state::JoinRule::Invite:
        return tr("%1 made this room require and invitation to join.").arg(name);
    case mtx::events::state::JoinRule::Knock:
        return tr("%1 allowed to join this room by knocking.").arg(name);
    case mtx::events::state::JoinRule::Restricted: {
        QStringList rooms;
        for (const auto &r : event->content.allow) {
            if (r.type == mtx::events::state::JoinAllowanceType::RoomMembership)
                rooms.push_back(QString::fromStdString(r.room_id));
        }
        return tr("%1 allowed members of the following rooms to automatically join this "
                  "room: %2")
          .arg(name)
          .arg(rooms.join(", "));
    }
    default:
        // Currently, knock and private are reserved keywords and not implemented in Matrix.
        return "";
    }
}

QString
TimelineModel::formatGuestAccessEvent(QString id)
{
    mtx::events::collections::TimelineEvents *e = events.get(id.toStdString(), "");
    if (!e)
        return "";

    auto event = std::get_if<mtx::events::StateEvent<mtx::events::state::GuestAccess>>(e);
    if (!event)
        return "";

    QString user = QString::fromStdString(event->sender);
    QString name = utils::replaceEmoji(displayName(user));

    switch (event->content.guest_access) {
    case mtx::events::state::AccessState::CanJoin:
        return tr("%1 made the room open to guests.").arg(name);
    case mtx::events::state::AccessState::Forbidden:
        return tr("%1 has closed the room to guest access.").arg(name);
    default:
        return "";
    }
}

QString
TimelineModel::formatHistoryVisibilityEvent(QString id)
{
    mtx::events::collections::TimelineEvents *e = events.get(id.toStdString(), "");
    if (!e)
        return "";

    auto event = std::get_if<mtx::events::StateEvent<mtx::events::state::HistoryVisibility>>(e);

    if (!event)
        return "";

    QString user = QString::fromStdString(event->sender);
    QString name = utils::replaceEmoji(displayName(user));

    switch (event->content.history_visibility) {
    case mtx::events::state::Visibility::WorldReadable:
        return tr("%1 made the room history world readable. Events may be now read by "
                  "non-joined people.")
          .arg(name);
    case mtx::events::state::Visibility::Shared:
        return tr("%1 set the room history visible to members from this point on.").arg(name);
    case mtx::events::state::Visibility::Invited:
        return tr("%1 set the room history visible to members since they were invited.").arg(name);
    case mtx::events::state::Visibility::Joined:
        return tr("%1 set the room history visible to members since they joined the room.")
          .arg(name);
    default:
        return "";
    }
}

QString
TimelineModel::formatPowerLevelEvent(QString id)
{
    mtx::events::collections::TimelineEvents *e = events.get(id.toStdString(), "");
    if (!e)
        return "";

    auto event = std::get_if<mtx::events::StateEvent<mtx::events::state::PowerLevels>>(e);
    if (!event)
        return "";

    QString user = QString::fromStdString(event->sender);
    QString name = utils::replaceEmoji(displayName(user));

    // TODO: power levels rendering is actually a bit complex. work on this later.
    return tr("%1 has changed the room's permissions.").arg(name);
}

QVariantMap
TimelineModel::formatRedactedEvent(QString id)
{
    QVariantMap pair{{"first", ""}, {"second", ""}};
    mtx::events::collections::TimelineEvents *e = events.get(id.toStdString(), "");
    if (!e)
        return pair;

    auto event = std::get_if<mtx::events::RoomEvent<mtx::events::msg::Redacted>>(e);
    if (!event)
        return pair;

    QString dateTime = QDateTime::fromMSecsSinceEpoch(event->origin_server_ts).toString();
    QString reason   = "";
    auto because     = event->unsigned_data.redacted_because;
    // User info about who actually sent the redacted event.
    QString redactedUser;
    QString redactedName;

    if (because.has_value()) {
        redactedUser = QString::fromStdString(because->sender).toHtmlEscaped();
        redactedName = utils::replaceEmoji(displayName(redactedUser));
        reason       = QString::fromStdString(because->content.reason).toHtmlEscaped();
    }

    if (reason.isEmpty()) {
        pair["first"] = tr("Removed by %1").arg(redactedName);
        pair["second"] =
          tr("%1 (%2) removed this message at %3").arg(redactedName, redactedUser, dateTime);
    } else {
        pair["first"]  = tr("Removed by %1 because: %2").arg(redactedName, reason);
        pair["second"] = tr("%1 (%2) removed this message at %3\nReason: %4")
                           .arg(redactedName, redactedUser, dateTime, reason);
    }

    return pair;
}

void
TimelineModel::acceptKnock(QString id)
{
    mtx::events::collections::TimelineEvents *e = events.get(id.toStdString(), "");
    if (!e)
        return;

    auto event = std::get_if<mtx::events::StateEvent<mtx::events::state::Member>>(e);
    if (!event)
        return;

    if (!permissions_.canInvite())
        return;

    if (cache::isRoomMember(event->state_key, room_id_.toStdString()))
        return;

    using namespace mtx::events::state;
    if (event->content.membership != Membership::Knock)
        return;

    ChatPage::instance()->inviteUser(QString::fromStdString(event->state_key), "");
}

bool
TimelineModel::showAcceptKnockButton(QString id)
{
    mtx::events::collections::TimelineEvents *e = events.get(id.toStdString(), "");
    if (!e)
        return false;

    auto event = std::get_if<mtx::events::StateEvent<mtx::events::state::Member>>(e);
    if (!event)
        return false;

    if (!permissions_.canInvite())
        return false;

    if (cache::isRoomMember(event->state_key, room_id_.toStdString()))
        return false;

    using namespace mtx::events::state;
    return event->content.membership == Membership::Knock;
}

QString
TimelineModel::formatMemberEvent(QString id)
{
    mtx::events::collections::TimelineEvents *e = events.get(id.toStdString(), "");
    if (!e)
        return "";

    auto event = std::get_if<mtx::events::StateEvent<mtx::events::state::Member>>(e);
    if (!event)
        return "";

    mtx::events::StateEvent<mtx::events::state::Member> *prevEvent = nullptr;
    if (!event->unsigned_data.replaces_state.empty()) {
        auto tempPrevEvent = events.get(event->unsigned_data.replaces_state, event->event_id);
        if (tempPrevEvent) {
            prevEvent =
              std::get_if<mtx::events::StateEvent<mtx::events::state::Member>>(tempPrevEvent);
        }
    }

    QString user = QString::fromStdString(event->state_key);
    QString name = utils::replaceEmoji(displayName(user));
    QString rendered;

    // see table https://matrix.org/docs/spec/client_server/latest#m-room-member
    using namespace mtx::events::state;
    switch (event->content.membership) {
    case Membership::Invite:
        rendered = tr("%1 was invited.").arg(name);
        break;
    case Membership::Join:
        if (prevEvent && prevEvent->content.membership == Membership::Join) {
            QString oldName = utils::replaceEmoji(
              QString::fromStdString(prevEvent->content.display_name).toHtmlEscaped());

            bool displayNameChanged =
              prevEvent->content.display_name != event->content.display_name;
            bool avatarChanged = prevEvent->content.avatar_url != event->content.avatar_url;

            if (displayNameChanged && avatarChanged)
                rendered = tr("%1 has changed their avatar and changed their "
                              "display name to %2.")
                             .arg(oldName, name);
            else if (displayNameChanged)
                rendered = tr("%1 has changed their display name to %2.").arg(oldName, name);
            else if (avatarChanged)
                rendered = tr("%1 changed their avatar.").arg(name);
            else
                rendered = tr("%1 changed some profile info.").arg(name);
            // the case of nothing changed but join follows join shouldn't happen, so
            // just show it as join
        } else {
            if (event->content.join_authorised_via_users_server.empty())
                rendered = tr("%1 joined.").arg(name);
            else
                rendered =
                  tr("%1 joined via authorisation from %2's server.")
                    .arg(name)
                    .arg(QString::fromStdString(event->content.join_authorised_via_users_server));
        }
        break;
    case Membership::Leave:
        if (!prevEvent) // Should only ever happen temporarily
            return "";

        if (prevEvent->content.membership == Membership::Invite) {
            if (event->state_key == event->sender)
                rendered = tr("%1 rejected their invite.").arg(name);
            else
                rendered = tr("Revoked the invite to %1.").arg(name);
        } else if (prevEvent->content.membership == Membership::Join) {
            if (event->state_key == event->sender)
                rendered = tr("%1 left the room.").arg(name);
            else
                rendered = tr("Kicked %1.").arg(name);
        } else if (prevEvent->content.membership == Membership::Ban) {
            rendered = tr("Unbanned %1.").arg(name);
        } else if (prevEvent->content.membership == Membership::Knock) {
            if (event->state_key == event->sender)
                rendered = tr("%1 redacted their knock.").arg(name);
            else
                rendered = tr("Rejected the knock from %1.").arg(name);
        } else
            return tr("%1 left after having already left!",
                      "This is a leave event after the user already left and shouldn't "
                      "happen apart from state resets")
              .arg(name);
        break;

    case Membership::Ban:
        rendered = tr("%1 was banned.").arg(name);
        break;
    case Membership::Knock:
        rendered = tr("%1 knocked.").arg(name);
        break;
    }

    if (event->content.reason != "") {
        rendered += " " + tr("Reason: %1").arg(QString::fromStdString(event->content.reason));
    }

    return rendered;
}

void
TimelineModel::setEdit(QString newEdit)
{
    if (newEdit.isEmpty()) {
        resetEdit();
        return;
    }

    if (edit_.isEmpty()) {
        this->textBeforeEdit  = input()->text();
        this->replyBeforeEdit = reply_;
        nhlog::ui()->debug("Stored: {}", textBeforeEdit.toStdString());
    }

    if (edit_ != newEdit) {
        auto ev = events.get(newEdit.toStdString(), "");
        if (ev && mtx::accessors::sender(*ev) == http::client()->user_id().to_string()) {
            auto e = *ev;
            setReply(QString::fromStdString(mtx::accessors::relations(e).reply_to().value_or("")));

            auto msgType = mtx::accessors::msg_type(e);
            if (msgType == mtx::events::MessageType::Text ||
                msgType == mtx::events::MessageType::Notice ||
                msgType == mtx::events::MessageType::Emote) {
                auto relInfo  = relatedInfo(newEdit);
                auto editText = relInfo.quoted_body;

                if (!relInfo.quoted_formatted_body.isEmpty()) {
                    auto matches =
                      conf::strings::matrixToLink.globalMatch(relInfo.quoted_formatted_body);
                    std::map<QString, QString> reverseNameMapping;
                    while (matches.hasNext()) {
                        auto m                            = matches.next();
                        reverseNameMapping[m.captured(2)] = m.captured(1);
                    }

                    for (const auto &[user, link] : reverseNameMapping) {
                        // TODO(Nico): html unescape the user name
                        editText.replace(user, QStringLiteral("[%1](%2)").arg(user, link));
                    }
                }

                if (msgType == mtx::events::MessageType::Emote)
                    input()->setText("/me " + editText);
                else
                    input()->setText(editText);
            } else {
                input()->setText("");
            }

            edit_ = newEdit;
        } else {
            resetReply();

            input()->setText("");
            edit_ = "";
        }
        emit editChanged(edit_);
    }
}

void
TimelineModel::resetEdit()
{
    if (!edit_.isEmpty()) {
        edit_ = "";
        emit editChanged(edit_);
        nhlog::ui()->debug("Restoring: {}", textBeforeEdit.toStdString());
        input()->setText(textBeforeEdit);
        textBeforeEdit.clear();
        if (replyBeforeEdit.isEmpty())
            resetReply();
        else
            setReply(replyBeforeEdit);
        replyBeforeEdit.clear();
    }
}

QString
TimelineModel::roomName() const
{
    auto info = cache::getRoomInfo({room_id_.toStdString()});

    if (!info.count(room_id_))
        return "";
    else
        return utils::replaceEmoji(QString::fromStdString(info[room_id_].name).toHtmlEscaped());
}

QString
TimelineModel::plainRoomName() const
{
    auto info = cache::getRoomInfo({room_id_.toStdString()});

    if (!info.count(room_id_))
        return "";
    else
        return QString::fromStdString(info[room_id_].name);
}

QString
TimelineModel::roomAvatarUrl() const
{
    auto info = cache::getRoomInfo({room_id_.toStdString()});

    if (!info.count(room_id_))
        return "";
    else
        return QString::fromStdString(info[room_id_].avatar_url);
}

QString
TimelineModel::roomTopic() const
{
    auto info = cache::getRoomInfo({room_id_.toStdString()});

    if (!info.count(room_id_))
        return "";
    else
        return utils::replaceEmoji(
          utils::linkifyMessage(QString::fromStdString(info[room_id_].topic).toHtmlEscaped()));
}

crypto::Trust
TimelineModel::trustlevel() const
{
    if (!isEncrypted_)
        return crypto::Trust::Unverified;

    return cache::client()->roomVerificationStatus(room_id_.toStdString());
}

int
TimelineModel::roomMemberCount() const
{
    return (int)cache::client()->memberCount(room_id_.toStdString());
}

QString
TimelineModel::directChatOtherUserId() const
{
    if (roomMemberCount() < 3) {
        QString id;
        for (auto member : cache::getMembers(room_id_.toStdString()))
            if (member.user_id != UserSettings::instance()->userId())
                id = member.user_id;
        return id;
    } else
        return "";
}