/*
 * Created by victoria on 2021-05-13.
 */

#include "conversations.h"

#include "qomemo/bundle.h"
#include "qomemo/device.h"
#include "shared/qxmppfactories.h"

#include <QDebug>
#include <QXmppIq.h>
#include <QXmppPubSubIq.h>

using namespace QXmpp::Omemo;
using namespace QXmpp::Factories;

QXmppElement Variant::Conversations::deviceToXml(const Device &device) {
    auto result = createElement("device");
    result.setAttribute("id", QString::number(device.id));

    return result;
}

Device Variant::Conversations::deviceFromXml(const QXmppElement &xml) {
    Device result{};

    if (!elementMatches(xml, "device"))
        return result;

    result.id = xml.attribute("id").toInt();

    return result;
}

QXmppElement
Variant::Conversations::deviceListToXml(const DeviceList &deviceList) {
    auto element = createElement("list", "eu.siacs.conversations.axolotl");

    for (const auto &device : deviceList.devices) {
        element.appendChild(deviceToXml(device));
    }

    return element;
}

std::optional<DeviceList> Variant::Conversations::latestDeviceListFromPubSubNode(const QXmppElement &items) {
    auto item = items.firstChildElement("item");
    if (item.isNull())
        return std::nullopt;

    auto list = item.firstChildElement("list");
    if (list.isNull())
        return std::nullopt;

    if (!elementMatches(list, "list", "eu.siacs.conversations.axolotl"))
        return std::nullopt;

    DeviceList result{};

    auto deviceElement = list.firstChildElement("device");
    while (!deviceElement.isNull()) {
        result.devices.push_back(deviceFromXml(deviceElement));
        deviceElement = deviceElement.nextSiblingElement("device");
    }

    return result;
}

QXmppIq Variant::Conversations::deviceListSetIq(const DeviceList &deviceList) {
    QXmppIq iq{};

    iq.setType(QXmppIq::Set);

    auto item = createElement("item");
    item.appendChild(deviceListToXml(deviceList));

    auto publish = createElement("publish");
    publish.setAttribute("node", getDeviceListNode());
    publish.appendChild(item);

    auto pubSub = createElement("pubsub", "http://jabber.org/protocol/pubsub");
    pubSub.appendChild(publish);
    pubSub.appendChild(createOpenPublishOptions());

    iq.setExtensions({ pubSub });

    return iq;
}

QString Variant::Conversations::getDeviceListNode() const {
    return "eu.siacs.conversations.axolotl.devicelist";
}

QXmppIq Variant::Conversations::bundleSetIq(int deviceId, const Bundle &bundle) {
    QXmppIq iq{};

    iq.setType(QXmppIq::Set);

    auto item = createElement("item");
    item.appendChild(bundleToXml(bundle));

    auto publish = createElement("publish");
    publish.setAttribute(
            "node",
            QString("eu.siacs.conversations.axolotl.bundles:%1").arg(deviceId));
    publish.appendChild(item);

    auto pubSub = createElement("pubsub", "http://jabber.org/protocol/pubsub");
    pubSub.appendChild(publish);
    pubSub.appendChild(createOpenPublishOptions());

    iq.setExtensions({ pubSub });

    return iq;
}

QXmppElement Variant::Conversations::bundleToXml(const Bundle &bundle) {
    auto spkNode = createElement("signedPreKeyPublic");
    spkNode.setAttribute("signedPreKeyId", QString::number(bundle.spkId));
    spkNode.setValue(bundle.spk.toBase64());

    auto spksNode = createElement("signedPreKeySignature");
    spksNode.setValue(bundle.spks.toBase64());

    auto ikNode = createElement("identityKey");
    ikNode.setValue(bundle.ik.toBase64());

    auto prekeysNode = createElement("prekeys");
    for (const auto &pk : bundle.prekeys) {
        prekeysNode.appendChild(preKeyToXml(pk));
    }

    auto result = createElement("bundle", "eu.siacs.conversations.axolotl");
    result.appendChild(spkNode);
    result.appendChild(spksNode);
    result.appendChild(ikNode);
    result.appendChild(prekeysNode);

    return result;
}

QXmppElement Variant::Conversations::preKeyToXml(const PreKey &pk) {
    auto x = createElement("preKeyPublic");
    x.setAttribute("preKeyId", QString::number(pk.id));
    x.setValue(pk.data.toBase64());

    return x;
}

std::optional<PreKey> Variant::Conversations::preKeyFromXml(const QXmppElement &xml) {
    if (!elementMatches(xml, "preKeyPublic"))
        return std::nullopt;

    auto pk = PreKey();
    pk.id = xml.attribute("preKeyId").toInt();
    pk.data = QByteArray::fromBase64Encoding(xml.value().toUtf8()).decoded;

    return pk;
}

std::optional<Bundle> Variant::Conversations::bundleFromXml(const QXmppElement &xml) {
    if (!elementMatches(xml, "bundle", "eu.siacs.conversations.axolotl"))
        return std::nullopt;

    auto spkNode = xml.firstChildElement("signedPreKeyPublic");
    if (spkNode.isNull()) {
        qWarning() << "'bundle': missing 'signedPreKeyPublic'";
        return std::nullopt;
    }

    Bundle result{};

    result.spk = QByteArray::fromBase64Encoding(spkNode.value().toUtf8()).decoded;
    result.spkId = spkNode.attribute("signedPreKeyId").toInt();

    auto spksNode = xml.firstChildElement("signedPreKeySignature");
    if (spksNode.isNull()) {
        qWarning() << "'bundle': missing 'signedPreKeySignature'";
        return std::nullopt;
    }

    result.spks = QByteArray::fromBase64Encoding(spksNode.value().toUtf8()).decoded;

    auto ikNode = xml.firstChildElement("identityKey");
    if (ikNode.isNull()) {
        qWarning() << "'bundle': missing 'identityKey'";
        return std::nullopt;
    }

    result.ik = QByteArray::fromBase64Encoding(ikNode.value().toUtf8()).decoded;

    auto prekeysNode = xml.firstChildElement("prekeys");
    auto pkNode = prekeysNode.firstChildElement("preKeyPublic");

    result.prekeys.clear();
    while (!pkNode.isNull()) {
        auto maybePk = preKeyFromXml(pkNode);
        if (maybePk)
            result.prekeys.push_back(*maybePk);
        pkNode = pkNode.nextSiblingElement("preKeyPublic");
    }

    return result;
}