#include "AreaData.h"

#include "geometry/MeasurementArea.h"
#include "geometry/SafeArea.h"
#include "geometry/snake.h"

#include "JsonHelper.h"
#include "QGCApplication.h"
#include "QGCLoggingCategory.h"
#include "QGCQGeoCoordinate.h"

QGC_LOGGING_CATEGORY(AreaDataLog, "AreaDataLog")

const char *originKey = "Origin";
const char *areaListKey = "AreaList";

AreaData::AreaData(QObject *parent) : QObject(parent) {}

AreaData::~AreaData() {}

AreaData::AreaData(const AreaData &other, QObject *parent) : QObject(parent) {
  *this = other;
}

AreaData &AreaData::operator=(const AreaData &other) {
  this->clear();

  // Clone elements.
  for (int i = 0; i < other._areaList.count(); ++i) {
    auto obj = other._areaList[i];
    auto area = qobject_cast<const GeoArea *>(obj);
    this->insert(area->clone(this));
  }

  _origin = other._origin;

  return *this;
}

bool AreaData::insert(GeoArea *areaData) {
  if (areaData != nullptr) {
    if (Q_LIKELY(!this->_areaList.contains(areaData))) {
      _areaList.append(areaData);
      emit areaListChanged();

      auto *measurementArea = qobject_cast<MeasurementArea *>(areaData);
      if (measurementArea != nullptr) {
        connect(measurementArea, &MeasurementArea::centerChanged, this,
                &AreaData::_updateOrigin);
        _setOrigin(measurementArea->center());
      }
      return true;
    }
  }

  return false;
}

void AreaData::remove(GeoArea *areaData) {
  int index = _areaList.indexOf(areaData);
  if (index >= 0) {
    QObject *obj = _areaList.removeAt(index);

    auto *measurementArea = qobject_cast<MeasurementArea *>(areaData);
    if (measurementArea != nullptr) {
      disconnect(measurementArea, &MeasurementArea::centerChanged, this,
                 &AreaData::_updateOrigin);
      _setOrigin(QGeoCoordinate());
    }

    if (obj->parent() == nullptr || obj->parent() == this) {
      obj->deleteLater();
    }

    emit areaListChanged();
  }
}

void AreaData::clear() {
  if (_areaList.count() > 0) {
    while (_areaList.count() > 0) {
      remove(_areaList.value<GeoArea *>(0));
    }
    emit areaListChanged();
  }
  _errorString.clear();
}

QmlObjectListModel *AreaData::areaList() { return &_areaList; }

const QmlObjectListModel *AreaData::areaList() const { return &_areaList; }

QGeoCoordinate AreaData::origin() const { return _origin; }

bool AreaData::isCorrect(bool showError) {
  if (!initialized()) {
    qCWarning(AreaDataLog) << "isCorrect(): not initialized";
    return false;
  }

  // Check if areas are correct
  if (!_areasCorrect(showError)) {
    return false;
  }

  // Check if areas where added.
  MeasurementArea *measurementArea = nullptr;
  SafeArea *safeArea = nullptr;
  if (!_getAreas(&measurementArea, &safeArea, showError)) {
    return false;
  }

  // Check if measurement area is covered by safe area.
  if (!_origin.isValid()) {
    qCWarning(AreaDataLog) << "isCorrect(): origin invalid";
    return false;
  }
  const auto &origin = this->origin();
  snake::FPolygon safeAreaENU;
  snake::areaToEnu(origin, safeArea->pathModel(), safeAreaENU);
  snake::FPolygon measurementAreaENU;
  snake::areaToEnu(origin, measurementArea->pathModel(), measurementAreaENU);
  //  qDebug() << "origin" << origin;
  //  std::stringstream ss;
  //  ss << "measurementAreaENU: " << bg::wkt(measurementAreaENU) << std::endl;
  //  ss << "safeAreaENU: " << bg::wkt(safeAreaENU) << std::endl;
  //  qDebug() << ss.str().c_str();
  if (!bg::covered_by(measurementAreaENU, safeAreaENU)) {
    _processError(tr("Measurement Area is not covered by Safe "
                     "Area. Please adjust "
                     "the areas accordingly.\n"),
                  showError);
    return false;
  }

  return true;
}

bool AreaData::initialize(const QGeoCoordinate &bottomLeft,
                          const QGeoCoordinate &topRight) {
  // bottomLeft and topRight define the bounding box.
  if (bottomLeft.isValid() && topRight.isValid() && bottomLeft != topRight) {
    auto *measurementArea = getGeoArea<MeasurementArea *>(_areaList);
    auto *safeArea = getGeoArea<SafeArea *>(_areaList);

    if (safeArea == nullptr) {
      safeArea = new SafeArea(this);
      if (!insert(safeArea)) {
        safeArea->deleteLater();
        qCCritical(AreaDataLog)
            << "initialize(): safeArea == nullptr, but insert() failed.";
        return false;
      }
    }

    if (measurementArea == nullptr) {
      measurementArea = new MeasurementArea(this);
      if (!insert(measurementArea)) {
        measurementArea->deleteLater();
        qCCritical(AreaDataLog) << "initialize(): measurementArea == nullptr, "
                                   "but insert() failed.";
        return false;
      }
    }

    // Fit safe area to bounding box.
    safeArea->clear();
    safeArea->appendVertex(bottomLeft);
    safeArea->appendVertex(
        QGeoCoordinate(topRight.latitude(), bottomLeft.longitude()));
    safeArea->appendVertex(topRight);
    safeArea->appendVertex(
        QGeoCoordinate(bottomLeft.latitude(), topRight.longitude()));

    // Put measurement area inside safeArea;
    measurementArea->clear();
    measurementArea->appendVertex(QGeoCoordinate(
        0.8 * bottomLeft.latitude() + 0.2 * topRight.latitude(),
        0.8 * bottomLeft.longitude() + 0.2 * topRight.longitude()));
    measurementArea->appendVertex(QGeoCoordinate(
        0.2 * bottomLeft.latitude() + 0.8 * topRight.latitude(),
        0.8 * bottomLeft.longitude() + 0.2 * topRight.longitude()));
    measurementArea->appendVertex(QGeoCoordinate(
        0.2 * bottomLeft.latitude() + 0.8 * topRight.latitude(),
        0.2 * bottomLeft.longitude() + 0.8 * topRight.longitude()));
    measurementArea->appendVertex(QGeoCoordinate(
        0.8 * bottomLeft.latitude() + 0.2 * topRight.latitude(),
        0.2 * bottomLeft.longitude() + 0.8 * topRight.longitude()));

    // Set depot
    safeArea->setDepot(QGeoCoordinate(
        safeArea->vertexCoordinate(0).latitude() * 0.5 +
            measurementArea->vertexCoordinate(0).latitude() * 0.5,
        safeArea->vertexCoordinate(0).longitude() * 0.5 +
            measurementArea->vertexCoordinate(0).longitude() * 0.5));

    return true;
  } else {
    qCWarning(AreaDataLog)
        << "initialize(): bounding box invaldid (bottomLeft, topRight) "
        << bottomLeft << "," << topRight;
    return false;
  }
}

bool AreaData::initialized() {
  auto measurementArea = getGeoArea<MeasurementArea *>(_areaList);
  auto safeArea = getGeoArea<SafeArea *>(_areaList);
  return measurementArea != nullptr && safeArea != nullptr &&
         measurementArea->count() >= 3 && safeArea->count() >= 3;
}

void AreaData::intersection(bool showError) {
  if (initialized() && _areasCorrect(showError)) {
    MeasurementArea *measurementArea = nullptr;
    SafeArea *safeArea = nullptr;
    if (_getAreas(&measurementArea, &safeArea, showError)) {

      // convert to ENU
      const auto origin = this->origin();
      snake::FPolygon safeAreaENU;
      snake::areaToEnu(origin, safeArea->pathModel(), safeAreaENU);
      snake::FPolygon measurementAreaENU;
      snake::areaToEnu(origin, measurementArea->pathModel(),
                       measurementAreaENU);

      // do intersection
      std::deque<snake::FPolygon> outputENU;
      boost::geometry::intersection(measurementAreaENU, safeAreaENU, outputENU);

      if (outputENU.size() < 1 || outputENU[0].outer().size() < 4) {
        _processError("Intersection did't deliver any result. The Measurement "
                      "Area(s) and "
                      "The Safe Area must touch each other.",
                      showError);
        return;
      }

      if (outputENU[0].inners().size() > 0 || outputENU.size() > 1) {
        _processError(
            "Hint: Only simple polygons can be displayed. If Intersection"
            "produces polygons with holes or multi polygons, only "
            "partial information can be displayed.",
            showError);
      }

      // Shrink the result if safeAreaENU doesn't cover it.
      auto large = std::move(outputENU[0]);
      snake::FPolygon small;
      while (!bg::covered_by(large, safeAreaENU)) {
        snake::offsetPolygon(large, small, -0.1);
        large = std::move(small);
      }

      // Check if result is different from input.
      if (!bg::equals(large, measurementAreaENU)) {
        // Convert.
        measurementArea->clear();
        for (auto it = large.outer().begin(); it != large.outer().end() - 1;
             ++it) {
          QGeoCoordinate c;
          snake::fromENU(origin, *it, c);
          measurementArea->appendVertex(c);
        }
      }
    }
  }
}

QVector<MeasurementArea *> AreaData::measurementAreaArray() {
  return getGeoAreaList<MeasurementArea *, QVector>(_areaList);
}

QVector<SafeArea *> AreaData::safeAreaArray() {
  return getGeoAreaList<SafeArea *, QVector>(_areaList);
}

QmlObjectListModel *AreaData::measurementAreaList() {
  _measurementAreaList.clear();
  auto array = getGeoAreaList<MeasurementArea *, QVector>(_areaList);
  for (auto area : array)
    _measurementAreaList.append(area);
  return &_measurementAreaList;
}

QmlObjectListModel *AreaData::safeAreaList() {
  _safeAreaList.clear();
  auto array = getGeoAreaList<SafeArea *, QVector>(_areaList);
  for (auto &area : array)
    _safeAreaList.append(area);
  return &_safeAreaList;
}

bool AreaData::operator==(const AreaData &other) const {
  if (_areaList.count() == other._areaList.count()) {
    for (int i = 0; i < _areaList.count(); ++i) {
      if (_areaList[i] != other._areaList[i]) {
        return false;
      }
    }
    return true;
  } else {
    return false;
  }
}
bool AreaData::operator!=(const AreaData &other) const {
  return !(*this == other);
}

bool AreaData::load(const QJsonObject &obj, QString &errorString) {
  bool returnValue = true;

  // load areaList.
  if (obj.contains(areaListKey) && obj[areaListKey].isArray()) {

    this->clear();

    // iterate over json array
    for (const auto valueRef : obj[areaListKey].toArray()) {
      const auto jsonArea = valueRef.toObject();

      // check if area type key is present
      if (jsonArea.contains(GeoArea::areaTypeKey) &&
          jsonArea[GeoArea::areaTypeKey].isString()) {

        // load MeasurementArea
        if (jsonArea[GeoArea::areaTypeKey].toString() ==
            MeasurementArea::nameString) {

          auto area = getGeoArea<MeasurementArea *>(_areaList);

          if (area == nullptr) {

            auto area = new MeasurementArea(this);
            QString e;
            if (area->loadFromJson(jsonArea, e)) {
              this->insert(area);
            } else {
              returnValue = false;
              errorString.append(e);
              errorString.append("\n");
              area->deleteLater();
            }
          } else {
            returnValue = false;
            errorString.append(
                tr("Multiple Measurement Areas detected. Area was ignored."));
          }
        }
        // load SafeArea
        else if (jsonArea[GeoArea::areaTypeKey].toString() ==
                 SafeArea::nameString) {

          auto area = getGeoArea<SafeArea *>(_areaList);
          if (area == nullptr) {

            auto area = new SafeArea(this);
            QString e;
            if (area->loadFromJson(jsonArea, e)) {
              this->insert(area);
            } else {
              returnValue = false;
              errorString.append(e);
              errorString.append("\n");
              area->deleteLater();
            }
          } else {
            returnValue = false;
            errorString.append(
                tr("Multiple Safe Areas detected. Area was ignored."));
          }
        }
        // unknown area
        else {
          returnValue = false;
          errorString.append(tr("Unknown area type: ") +
                             jsonArea[GeoArea::areaTypeKey].toString());
        }
      } else {
        // GeoArea::areaTypeKey missing
        returnValue = false;
        errorString.append(
            "Area type key missing, not able to determine area type.\n");
      }
    }
  } else {
    // AreaList missing
    returnValue = false;
    errorString.append("Not able to load areas.\n");
  }

  // load origin
  if (obj.contains(originKey) && obj[originKey].isObject()) {
    QGeoCoordinate origin;
    QString e;
    if (JsonHelper::loadGeoCoordinate(obj[originKey], false, origin, e)) {
      _origin = origin;
    }
  }

  return returnValue;
}

bool AreaData::save(QJsonObject &obj) {
  QJsonObject temp;

  QJsonValue jsonOrigin;
  JsonHelper::saveGeoCoordinate(_origin, false, jsonOrigin);
  temp[originKey] = jsonOrigin;

  QJsonArray jsonAreaList;
  for (int i = 0; i < _areaList.count(); ++i) {
    auto qobj = _areaList[i];
    auto area = qobject_cast<GeoArea *>(qobj);
    QJsonObject jsonArea;
    if (area->saveToJson(jsonArea)) {
      jsonAreaList.append(jsonArea);
    } else {
      qDebug(AreaDataLog) << "save(): not able to save area: "
                          << area->objectName();
      return false;
    }
  }
  temp[areaListKey] = jsonAreaList;

  obj = std::move(temp);
  return true;
}

void AreaData::_setOrigin(const QGeoCoordinate &origin) {
  if (this->_origin != origin) {
    this->_origin = origin;
    emit originChanged();
  }
}

void AreaData::_processError(const QString &str, bool showError) {
  this->_errorString = str;
  emit error();
  if (showError) {
    qgcApp()->informationMessageBoxOnMainThread(tr("Area Editor"),
                                                this->errorString());
  }
}

bool AreaData::_areasCorrect(bool showError) {
  // Check if areas are correct.
  for (int i = 0; i < _areaList.count(); ++i) {
    auto *area = _areaList.value<GeoArea *>(i);
    if (!area->isCorrect()) {
      _processError(area->errorString(), showError);
      return false;
    }
  }

  return true;
}

bool AreaData::_getAreas(MeasurementArea **measurementArea, SafeArea **safeArea,
                         bool showError) {
  *measurementArea = getGeoArea<MeasurementArea *>(_areaList);
  if (*measurementArea == nullptr) {
    _processError(
        tr("Measurement Area is missing. Please define a Measurement Area."),
        showError);
    return false;
  }
  *safeArea = getGeoArea<SafeArea *>(_areaList);
  if (*safeArea == nullptr) {
    _processError(tr("Safe Area is missing. Please define a Safe Area."),
                  showError);
    return false;
  }

  return true;
}

void AreaData::_updateOrigin() {
  auto *measurementArea = getGeoArea<MeasurementArea *>(_areaList);
  if (measurementArea != nullptr) {
    _setOrigin(measurementArea->center());
  }
}

QString AreaData::errorString() const { return _errorString; }