qdeclarativegeojsondata.cpp

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// Copyright (C) 2019 Julian Sherollari <jdotsh@gmail.com>
// Copyright (C) 2023 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qdeclarativegeojsondata_p.h"
 
#include <QtLocation/private/qgeojson_p.h>
 
QT_BEGIN_NAMESPACE
 
namespace extractor
{
    static bool hasProperties(QQuickItem *item)
    {
        QVariant props = item->property("props");
        return !props.isNull();
    }
 
    static QVariant toVariant(QObject *mapItem)
    {
        if (QDeclarativeGeoMapItemView *miv = qobject_cast<QDeclarativeGeoMapItemView *>(mapItem)) {
            return toVariant(miv);
        } else if (QDeclarativePolylineMapItem *polyline = qobject_cast<QDeclarativePolylineMapItem *>(mapItem)) {
            return toVariant(polyline);
        } else if (QDeclarativePolygonMapItem *polygon = qobject_cast<QDeclarativePolygonMapItem *>(mapItem)) {
            return toVariant(polygon);
        } else if (QDeclarativeCircleMapItem *circle = qobject_cast<QDeclarativeCircleMapItem *>(mapItem)) {
            return toVariant(circle); // If GeoJSON Point type is visualized in other ways, handle those types here instead.
        } else if (QDeclarativeRectangleMapItem *rectangle = qobject_cast<QDeclarativeRectangleMapItem *>(mapItem)) {
            return toVariant(rectangle); // For the self-drawn rectangles. Will be exported as Polygons
        }
        return QVariant();
    }
 
    static QVariantMap toVariant(QDeclarativePolygonMapItem *mapPolygon)
    {
        QVariantMap ls;
        ls[QStringLiteral("type")] = QStringLiteral("Polygon");
        ls[QStringLiteral("data")] = QVariant::fromValue(mapPolygon->geoShape());
        if (hasProperties(mapPolygon))
            ls[QStringLiteral("properties")] = mapPolygon->property("props").toMap();
        return ls;
    }
 
    static QVariantMap toVariant(QDeclarativePolylineMapItem *mapPolyline)
    {
        QVariantMap ls;
        ls[QStringLiteral("type")] = QStringLiteral("LineString");
        ls[QStringLiteral("data")] = QVariant::fromValue(mapPolyline->geoShape());
        if (hasProperties(mapPolyline))
            ls[QStringLiteral("properties")] = mapPolyline->property("props").toMap();
        return ls;
    }
 
    static QVariantMap toVariant(QDeclarativeCircleMapItem *mapCircle)
    {
        QVariantMap pt;
        pt[QStringLiteral("type")] = QStringLiteral("Point");
        pt[QStringLiteral("data")] = QVariant::fromValue(mapCircle->geoShape());
        QVariantMap propMap = mapCircle->property("props").toMap();
        propMap[QStringLiteral("radius")] = mapCircle->radius();
        pt[QStringLiteral("properties")] = propMap;
        return pt;
    }
 
    static QVariantMap toVariant(QDeclarativeRectangleMapItem *mapRectangle)
    {
        QVariantMap pt;
        pt[QStringLiteral("type")] = QStringLiteral("Polygon");
        QGeoRectangle rectanlge = mapRectangle->geoShape();
        QGeoPolygon poly;
        poly.addCoordinate(rectanlge.topLeft());
        poly.addCoordinate(rectanlge.topRight());
        poly.addCoordinate(rectanlge.bottomRight());
        poly.addCoordinate(rectanlge.bottomLeft());
        pt[QStringLiteral("data")] = QVariant::fromValue(poly);
        if (hasProperties(mapRectangle))
            pt[QStringLiteral("properties")] = mapRectangle->property("props").toMap();
        return pt;
    }
};
 
 
QDeclarativeGeoJsonData::QDeclarativeGeoJsonData(QObject *parent)
    : QObject(parent)
{
 
}
 
QDeclarativeGeoJsonData::~QDeclarativeGeoJsonData()
{
 
}
 
QVariant QDeclarativeGeoJsonData::model() const
{
    return m_content;
}
 
void QDeclarativeGeoJsonData::setModel(const QVariant &model)
{
    m_content = model;
    emit modelChanged();
}
 
 
QUrl QDeclarativeGeoJsonData::sourceUrl() const
{
    return m_url;
}
 
void QDeclarativeGeoJsonData::clear()
{
    m_content = QVariantList();
    emit modelChanged();
}
 
void QDeclarativeGeoJsonData::addItem(QQuickItem *item)
{
    QVariant entry;
    if (auto *polyline = qobject_cast<QDeclarativePolylineMapItem *>(item))
        entry = extractor::toVariant(polyline);
    else if (auto *polygon = qobject_cast<QDeclarativePolygonMapItem *>(item))
        entry = extractor::toVariant(polygon);
    else if (auto *circle = qobject_cast<QDeclarativeCircleMapItem *>(item))
        entry = extractor::toVariant(circle);
    else if (auto *rectangle = qobject_cast<QDeclarativeRectangleMapItem *>(item))
        entry = extractor::toVariant(rectangle);
    else
        return;
 
    QVariantList geoJson = m_content.toList();
    if (!geoJson.isEmpty()){
        QVariantList geoData = (geoJson[0].toMap()[QStringLiteral("type")] == QStringLiteral("FeatureCollection")) ? geoJson[0].toMap()[QStringLiteral("data")].toList() : geoJson;
        geoData.append(entry);
        geoJson[0] = QVariantMap{{QStringLiteral("type"), QStringLiteral("FeatureCollection")}, {QStringLiteral("data"), geoData}};
    }
    else {
        geoJson.append(entry);
    }
    m_content = geoJson;
    emit modelChanged();
}
 
bool QDeclarativeGeoJsonData::open()
{
    return openUrl(m_url);
}
 
bool QDeclarativeGeoJsonData::openUrl(const QUrl &url)
{
    // Reading GeoJSON file
    QFile loadFile(url.toLocalFile());
    if (!loadFile.open(QIODevice::ReadOnly)) {
        qWarning() << "Error while opening the file: " << url;
        qWarning() << loadFile.errorString();
        return false;
    }
 
    // Load the GeoJSON file using Qt's API
    QJsonParseError err;
    QJsonDocument loadDoc(QJsonDocument::fromJson(loadFile.readAll(), &err));
    if (err.error) {
         qWarning() << "Parsing while importing the JSON document:\n" << err.errorString();
         return false;
    }
 
    // Import geographic data to a QVariantList
    m_content = QGeoJson::importGeoJson(loadDoc);
    if (m_url != url) {
        m_url = url;
        emit sourceUrlChanged();
    }
    emit modelChanged();
    return true;
}
 
bool QDeclarativeGeoJsonData::saveAs(const QUrl &url)
{
    if (m_url != url){
        m_url = url;
        emit sourceUrlChanged();
    }
    return save();
}
 
bool QDeclarativeGeoJsonData::save()
{
    return dumpGeoJSON(m_content.toList(), m_url);
}
 
void QDeclarativeGeoJsonData::setModelToMapContents(QDeclarativeGeoMap *map)
{
    m_content = toVariant(map);
    emit modelChanged();
}
 
QVariantList QDeclarativeGeoJsonData::toVariant(QDeclarativeGeoMap *map)
{
    QVariantList res;
    const QList<QObject*> mapChildren = map->children();
    for (QObject *child : mapChildren) {
        QVariant mapItemAsVariant = extractor::toVariant(child);
        if (mapItemAsVariant.isValid())
            res.append(mapItemAsVariant);
    }
    return res;
}
 
bool QDeclarativeGeoJsonData::dumpGeoJSON(const QVariantList &geoJson, const QUrl &url)
{
    QJsonDocument json = QGeoJson::exportGeoJson(geoJson);
    QFile jsonFile(url.toLocalFile());
    if (!jsonFile.open(QIODevice::WriteOnly))
        return false;
    jsonFile.write(json.toJson());
    jsonFile.close();
    return true;
}
 
bool QDeclarativeGeoJsonData::writeDebug(const QVariantList &geoJson, const QUrl &url)
{
    QString prettyPrint = QGeoJson::toString(geoJson);
    QFile debugFile(url.toLocalFile());
    if (!debugFile.open(QIODevice::WriteOnly))
        return false;
    debugFile.write(prettyPrint.toUtf8());
    debugFile.close();
    return true;
}
 
QString QDeclarativeGeoJsonData::toString(const QVariantList &geoJson)
{
    return QGeoJson::toString(geoJson);
}
 
QT_END_NAMESPACE