/*
 * Created by victoria on 2021-05-12.
 */

#include "qomemo.h"
#include "sce.h"
#include <shared/qxmppfactories.h>

#include <QBuffer>
#include <QDebug>
#include <QDomDocument>

using namespace QXmpp::Factories;

QXmppElement QXmpp::Omemo::DeviceList::toXml() const {
  auto element = createElement("list", "eu.siacs.conversations.axolotl");

  for (const auto &d : devices) {
    element.appendChild(d.toXml());
  }

  return element;
}

QXmppIq QXmpp::Omemo::DeviceList::toIq() const {
  QXmppIq iq{};

  iq.setType(QXmppIq::Set);

  auto item = createElement("item");
  item.appendChild(toXml());

  auto publish = createElement("publish");
  publish.setAttribute("node", "eu.siacs.conversations.axolotl.devicelist");
  publish.appendChild(item);

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

  iq.extensions().push_back(pubSub);

  return iq;
}

void QXmpp::Omemo::DeviceList::fromXml(const QXmppElement &element) {
  if (!elementMatches(element, "list", "eu.siacs.conversations.axolotl"))
    return;

  devices.clear();

  auto deviceElement = element.firstChildElement("device");
  while (!deviceElement.isNull()) {
    Device device{};
    device.fromXml(deviceElement);
    devices.push_back(device);

    deviceElement = deviceElement.nextSiblingElement("device");
  }
}

QXmppElement QXmpp::Omemo::Device::toXml() const {
  auto result = createElement("device");
  result.setAttribute("id", QString::number(id));

  return result;
}

void QXmpp::Omemo::Device::fromXml(const QXmppElement &element) {
  if (!elementMatches(element, "device"))
    return;

  id = element.attribute("id").toInt();
}

QXmppElement QXmpp::Omemo::PreKey::toXml() const {
  auto pk = createElement("preKeyPublic");
  pk.setAttribute("preKeyId", QString::number(id));
  // TODO: Base64
  pk.setValue(data);

  return pk;
}

void QXmpp::Omemo::PreKey::fromXml(const QXmppElement &element) {
  if (!elementMatches(element, "preKeyPublic"))
    return;

  id = element.attribute("preKeyId").toInt();
  // TODO: Base64
  data = element.value();
}

QXmppElement QXmpp::Omemo::Bundle::toXml() const {
  auto spkNode = createElement("signedPreKeyPublic");
  spkNode.setAttribute("signedPreKeyId", QString::number(spkId));
  spkNode.setValue(spk);

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

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

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

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

  return result;
}

QXmppIq QXmpp::Omemo::Bundle::toIq(int deviceId) const {
  QXmppIq iq{};

  iq.setType(QXmppIq::Set);

  auto item = createElement("item");
  item.appendChild(toXml());

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

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

  iq.extensions().push_back(pubSub);

  return iq;
}

void QXmpp::Omemo::Bundle::fromXml(const QXmppElement &element) {
  if (!elementMatches(element, "bundle", "eu.siacs.conversations.axolotl"))
    return;

  auto spkNode = element.firstChildElement("spk");
  if (spkNode.isNull()) {
    qWarning() << "'bundle': missing 'spk'";
    return;
  }
  spk = spkNode.value();
  spkId = spkNode.attribute("id").toInt();

  auto spksNode = element.firstChildElement("spks");
  if (spksNode.isNull()) {
    qWarning() << "'bundle': missing 'spks'";
    return;
  }
  spks = spksNode.value();

  auto ikNode = element.firstChildElement("ik");
  if (ikNode.isNull()) {
    qWarning() << "'bundle': missing 'ik'";
    return;
  }
  ik = ikNode.value();

  auto prekeysNode = element.firstChildElement("prekeys");
  auto pkNode = prekeysNode.firstChildElement("pk");

  prekeys.clear();
  while (!pkNode.isNull()) {
    PreKey pk{};
    pk.fromXml(pkNode);
    prekeys.push_back(pk);
  }
}

QXmppPubSubIq QXmpp::Omemo::Bundle::fetchDeviceBundleIq(int deviceId) {
  QXmppPubSubIq iq{};
  iq.setType(QXmppIq::Get);
  iq.setQueryNode(QString("eu.siacs.conversations.axolotl.bundles:%1").arg(deviceId));

  QXmppPubSubItem item{};
  item.setId(QString::number(deviceId));
  iq.setItems({item});

  return iq;
}

QXmppElement QXmpp::Omemo::EncryptedMessage::header() const {
  auto result = createElement("header");
  result.setAttribute("sid", QString::number(fromDeviceId));

  auto ivNode = createElement("iv");
  ivNode.setValue(iv);

  for (const auto &key : keys) {
    result.appendChild(key.toXml());
  }

  return result;
}

QXmppElement QXmpp::Omemo::EncryptedMessage::toXml() const {
  auto result = createElement("encrypted", "eu.siacs.conversations.axolotl");

  result.appendChild(header());
  // TODO: Payload is optional
  result.appendChild(payload());

  return result;
}

QXmppElement QXmpp::Omemo::EncryptedMessage::payload() const {
  QBuffer buffer;
  buffer.open(QIODevice::ReadWrite);
  QXmlStreamWriter writer(&buffer);
  message.toXml(&writer);

  QDomDocument doc;
  doc.setContent(buffer.data(), true);

  QXmppElement root(doc.documentElement());
  root.setTagName("payload");

  return root;
}

QXmppElement QXmpp::Omemo::EncryptedMessage::content() const {
  auto envelope = createElement("content", "urn:xmpp:sce:0");

  envelope.appendChild(payload());

  if (!from.isEmpty()) {
    auto fromNode = createElement("from");
    fromNode.setAttribute("jid", from);
    envelope.appendChild(fromNode);
  }

  if (!to.isEmpty()) {
    auto toNode = createElement("to");
    toNode.setAttribute("jid", to);
    envelope.appendChild(toNode);
  }

  if (!timestamp.isNull()) {
    auto timeNode = createElement("time");
    timeNode.setAttribute("stamp", timestamp.toString(Qt::DateFormat::ISODate));
    envelope.appendChild(timeNode);
  }

  auto rpad = createElement("rpad");
  rpad.setValue(QXmpp::Sce::generatePadding());
  envelope.appendChild(rpad);

  return envelope;
}

QXmppElement QXmpp::Omemo::MessageKey::toXml() const {
  auto result = createElement("key");

  result.setAttribute("rid", QString::number(receivingDeviceId));
  if (prekey)
    result.setAttribute("prekey", "true");

  result.setValue(key);

  return result;
}