/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the QtLocation module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL3$
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** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
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** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPLv3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or later as published by the Free
** Software Foundation and appearing in the file LICENSE.GPL included in
** the packaging of this file. Please review the following information to
** ensure the GNU General Public License version 2.0 requirements will be
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** $QT_END_LICENSE$
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****************************************************************************/

#include "qgeoroutexmlparser.h"

#include <QXmlStreamReader>
#include <QStringList>
#include <QString>
#include <QtCore/QThreadPool>
#include <QDebug>

#include <QtPositioning/QGeoRectangle>
#include <QtPositioning/QGeoPath>
#include <QtLocation/QGeoRoute>
#include <QtLocation/private/qgeoroutesegment_p.h>

QT_BEGIN_NAMESPACE

QGeoDynamicSpeedInfoContainer::QGeoDynamicSpeedInfoContainer()
: trafficSpeed(0)
, baseSpeed(0)
, trafficTime(0)
, baseTime(0)
{}

QGeoRouteXmlParser::QGeoRouteXmlParser(const QGeoRouteRequest &request)
        : m_request(request)
{
}

QGeoRouteXmlParser::~QGeoRouteXmlParser()
{
}

void QGeoRouteXmlParser::parse(const QByteArray &data)
{
    m_data = data;
//    QFile file("/tmp/here.xml");
//    file.open(QIODevice::WriteOnly);
//    file.write(data);
//    file.close();
    QThreadPool::globalInstance()->start(this);
}

void QGeoRouteXmlParser::run()
{
    m_reader = new QXmlStreamReader(m_data);

    if (!parseRootElement())
        emit error(m_reader->errorString());
    else
        emit results(m_results);

    delete m_reader;
    m_reader = 0;
}

bool QGeoRouteXmlParser::parseRootElement()
{
    if (!m_reader->readNextStartElement()) {
        m_reader->raiseError("Expected a root element named \"CalculateRoute\" (no root element found).");
        return false;
    }

    if (m_reader->name() == QLatin1String("Error")) {
        QXmlStreamAttributes attributes = m_reader->attributes();
        if (attributes.value(QStringLiteral("type")) == QLatin1String("ApplicationError")
            && attributes.value("subtype") == QLatin1String("NoRouteFound"))
            return true;
    }

    bool updateroute = false;
    if (m_reader->name() != "CalculateRoute" && m_reader->name() != "GetRoute")  {
        m_reader->raiseError(QString("The root element is expected to have the name \"CalculateRoute\" or \"GetRoute\" (root element was named \"%1\").").arg(m_reader->name().toString()));
        return false;
    } else if (m_reader->name() == "GetRoute") {
        updateroute = true;
    }

    if (m_reader->readNextStartElement()) {
        if (m_reader->name() != "Response") {
            m_reader->raiseError(QString("Expected a element named \"Response\" (element was named \"%1\").").arg(m_reader->name().toString()));
            return false;
        }
    }

    while (m_reader->readNextStartElement() && !m_reader->hasError()) {
        if (m_reader->name() == "Route") {
            QGeoRoute route;
            route.setRequest(m_request);
            if (updateroute)
                route.setTravelMode(QGeoRouteRequest::TravelMode(int(m_request.travelModes())));
            if (!parseRoute(&route))
                continue; //route parsing failed move on to the next
            m_results.append(route);
        } else if (m_reader->name() == "Progress") {
            //TODO: updated route progress
            m_reader->skipCurrentElement();
        } else {
            m_reader->skipCurrentElement();
        }
    }

    return !m_reader->hasError();
}

bool QGeoRouteXmlParser::parseRoute(QGeoRoute *route)
{
    Q_ASSERT(m_reader->isStartElement() && m_reader->name() == "Route");
    m_maneuvers.clear();
//    m_segments.clear();
    m_legs.clear();
    int legIndex = 0;
    m_reader->readNext();
    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement && m_reader->name() == "Route") &&
           !m_reader->hasError()) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            if (m_reader->name() == "RouteId") {
                route->setRouteId(m_reader->readElementText());
            }
            //else if (m_reader->name() == "Waypoint") {
            //    succeeded = parseWaypoint(route);
            //}
            else if (m_reader->name() == "Mode") {
                if (!parseMode(route))
                    return false;
            } else if (m_reader->name() == "Shape") {
                QString elementName = m_reader->name().toString();
                QList<QGeoCoordinate> path;
                if (!parseGeoPoints(m_reader->readElementText(), &path, elementName))
                    return false;
                route->setPath(path);
            } else if (m_reader->name() == "BoundingBox") {
                QGeoRectangle bounds;
                if (!parseBoundingBox(bounds))
                    return false;
                route->setBounds(bounds);
            } else if (m_reader->name() == "Leg") {
                if (!parseLeg(legIndex++))
                    return false;
            } else if (m_reader->name() == "Summary") {
                if (!parseSummary(route))
                    return false;
            } else {
                m_reader->skipCurrentElement();
            }
        }
        m_reader->readNext();
    }

    if (m_reader->hasError())
        return false;

    return postProcessRoute(route);
}

bool QGeoRouteXmlParser::parseLeg(int legIndex)
{
    Q_ASSERT(m_reader->isStartElement() && m_reader->name() == QStringLiteral("Leg"));
    QGeoRouteLeg leg;
    leg.setLegIndex(legIndex);
    m_reader->readNext();
    QList<QGeoManeuverContainer> maneuvers;
    QList<QGeoRouteSegmentContainer> links;
    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement
             && m_reader->name() == QStringLiteral("Leg")) &&
           !m_reader->hasError()) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            if (m_reader->name() == QStringLiteral("Maneuver")) {
                if (!parseManeuver(maneuvers))
                    return false;
            }
// Currently unused, after requesting shape attribute in maneuvers.
// Links, however, contain additional info, such as speed limits, and might become needed in the future.
//            else if (m_reader->name() == QStringLiteral("Link")) {
//                if (!parseLink(links))
//                    return false;
//            }
            else if (m_reader->name() == "TravelTime") {
                leg.setTravelTime(qRound(m_reader->readElementText().toDouble()));
            } else if (m_reader->name() == "Length") {
                leg.setDistance(m_reader->readElementText().toDouble());
            } else {
                m_reader->skipCurrentElement();
            }
        }
        m_reader->readNext();
    }

    if (m_reader->hasError())
        return false;

    m_legs << leg;
//    m_segments << links;
    m_maneuvers << maneuvers;
    return true;
}

//static bool fuzzyCompare(const QGeoCoordinate &a, const QGeoCoordinate& b)
//{
//    return qFuzzyCompare(a.latitude(), b.latitude()) && qFuzzyCompare(a.longitude(), b.longitude());
//}

bool QGeoRouteXmlParser::postProcessRoute(QGeoRoute *route)
{
    QList<QList<QGeoRouteSegment>> legSegments;
    Q_ASSERT(m_maneuvers.size());


    // Step 3: populate the linkMap, linkId -> linkContainer
    for (int i = 0; i < m_maneuvers.size(); i++) {
        legSegments << QList<QGeoRouteSegment>();
        QList<QGeoRouteSegment> &segments = legSegments[i];
        QList<QGeoManeuverContainer> &maneuvers = m_maneuvers[i];
        for (int j = 0; j < m_maneuvers.at(i).size(); j++) {
            QGeoManeuverContainer &maneuver = maneuvers[j];
            QGeoRouteSegment segment;

            QVariantMap extendedAttributes;
            extendedAttributes["first"] = maneuver.first;
            extendedAttributes["last"] = maneuver.last;
            extendedAttributes["legIndex"] = i;
            extendedAttributes["id"] = maneuver.id;
            extendedAttributes["toLink"] = maneuver.toLink;
            extendedAttributes["index"] = j;
            maneuver.maneuver.setExtendedAttributes(extendedAttributes);

            segment.setDistance(maneuver.maneuver.distanceToNextInstruction());
            segment.setTravelTime(maneuver.maneuver.timeToNextInstruction());
            segment.setPath(maneuver.path);
            segment.setManeuver(maneuver.maneuver);
            segments << segment;
        }
    }

    // Step 7: connect all segments.
    QGeoRouteSegment segment;
    QGeoRouteSegment firstSegment;
    for (auto &segments: legSegments) {
        for (int j = 0; j < segments.size(); j++) {
            if (segment.isValid()) {
                segment.setNextRouteSegment(segments[j]);
            } else {
                firstSegment = segments[j];
            }
            segment = segments[j];
            if (j == segments.size() - 1) {
                QGeoRouteSegmentPrivate *sp = QGeoRouteSegmentPrivate::get(segment);
                sp->setLegLastSegment(true);
            }
        }
    }

    if (firstSegment.isValid())
        route->setFirstRouteSegment(firstSegment);

    // Step 8: fill route legs.
    for (int i = 0; i < m_legs.size(); i++) {
        m_legs[i].setTravelMode(route->travelMode());
        m_legs[i].setRequest(route->request());
        m_legs[i].setOverallRoute(*route);
        m_legs[i].setLegIndex(i);

        m_legs[i].setFirstRouteSegment(legSegments[i].first());

        // handle path
        QList<QGeoCoordinate> path;
        QGeoRouteSegment s = m_legs[i].firstRouteSegment();
        while (s.isValid()) {
            path.append(s.path());
            if (s.isLegLastSegment())
                break;
            s = s.nextRouteSegment();
        }
        m_legs[i].setPath(path);
        m_legs[i].setBounds(QGeoPath(path).boundingGeoRectangle());
    }
    route->setRouteLegs(m_legs);
    m_legs.clear();
//    m_segments.clear();
    m_maneuvers.clear();
    return true;
}

/*
bool QGeoRouteXmlParser::parseWaypoint(QGeoRoute *route)
{
    Q_ASSERT(m_reader->isStartElement() && m_reader->name() == "Waypoint");
    m_reader->readNext();
    QList<QGeoCoordinate> path(route->pathSummary());

    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement && m_reader->name() == "Waypoint")) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            if (m_reader->name() == "MappedPosition") {
                QGeoCoordinate coordinates;
                if(!parseCoordinates(coordinates))
                    return false;
                path.append(coordinates);
            }
            else {
                m_reader->skipCurrentElement();
            }
        }
        m_reader->readNext();
    }
    route->setPathSummary(path);
    return true;
}
*/

bool QGeoRouteXmlParser::parseMode(QGeoRoute *route)
{
    Q_ASSERT(m_reader->isStartElement() && m_reader->name() == "Mode");
    m_reader->readNext();

    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement && m_reader->name() == "Mode") &&
           !m_reader->hasError()) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            if (m_reader->name() == "TransportModes") {
                QString value = m_reader->readElementText();
                if (value == "car")
                    route->setTravelMode(QGeoRouteRequest::CarTravel);
                else if (value == "pedestrian")
                    route->setTravelMode(QGeoRouteRequest::PedestrianTravel);
                else if (value == "publicTransport")
                    route->setTravelMode(QGeoRouteRequest::PublicTransitTravel);
                else if (value == "bicycle")
                    route->setTravelMode(QGeoRouteRequest::BicycleTravel);
                else if (value == "truck")
                    route->setTravelMode(QGeoRouteRequest::TruckTravel);
                else {
                    // unsupported mode
                    m_reader->raiseError(QString("Unsupported travel mode '\"%1\"'").arg(value));
                    return false;
                }
            } else {
                m_reader->skipCurrentElement();
            }
        }
        m_reader->readNext();
    }
    return !m_reader->hasError();
}

bool QGeoRouteXmlParser::parseSummary(QGeoRoute *route)
{
    Q_ASSERT(route);
    Q_ASSERT(m_reader->isStartElement() && m_reader->name() == "Summary");
    m_reader->readNext();

    double baseTime = -1, trafficTime = -1;

    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement && m_reader->name() == "Summary") &&
           !m_reader->hasError()) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            if (m_reader->name() == "Distance") {
                route->setDistance(m_reader->readElementText().toDouble());
            } else if (m_reader->name() == "TrafficTime") {
                trafficTime = m_reader->readElementText().toDouble();
            } else if (m_reader->name() == "BaseTime") {
                baseTime = m_reader->readElementText().toDouble();
            } else {
                m_reader->skipCurrentElement();
            }
        }
        m_reader->readNext();
    }

    if (m_reader->hasError())
        return false;

    if (trafficTime >= 0)
        route->setTravelTime(trafficTime);
    else if (baseTime >= 0)
        route->setTravelTime(baseTime);

    return true;
}

bool QGeoRouteXmlParser::parseCoordinates(QGeoCoordinate &coord)
{
    QString currentElement = m_reader->name().toString();
    m_reader->readNext();

    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement && m_reader->name() == currentElement)  &&
           !m_reader->hasError()) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            QString name = m_reader->name().toString();
            QString value = m_reader->readElementText();
            if (name == "Latitude")
                coord.setLatitude(value.toDouble());
            else if (name == "Longitude")
                coord.setLongitude(value.toDouble());
        }
        m_reader->readNext();
    }

    return !m_reader->hasError();
}

bool QGeoRouteXmlParser::parseManeuver(QList<QGeoManeuverContainer> &maneuvers)
{
    Q_ASSERT(m_reader->isStartElement() && m_reader->name() == "Maneuver");

    if (!m_reader->attributes().hasAttribute("id")) {
        m_reader->raiseError("The element \"Maneuver\" did not have the required attribute \"id\".");
        return false;
    }
    QGeoManeuverContainer maneuverContainter;
    maneuverContainter.id = m_reader->attributes().value("id").toString();

    m_reader->readNext();
    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement && m_reader->name() == "Maneuver") &&
           !m_reader->hasError()) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            if (m_reader->name() == "Position") {
                QGeoCoordinate coordinates;
                if (parseCoordinates(coordinates))
                    maneuverContainter.maneuver.setPosition(coordinates);
            } else if (m_reader->name() == "Instruction") {
                maneuverContainter.maneuver.setInstructionText(m_reader->readElementText());
            } else if (m_reader->name() == "Shape") {
                QString elementName = m_reader->name().toString();
                QList<QGeoCoordinate> path;
                if (!parseGeoPoints(m_reader->readElementText(), &path, elementName))
                    return false;
                maneuverContainter.path = path;
            } else if (m_reader->name() == "ToLink") {
                maneuverContainter.toLink = m_reader->readElementText();
            } else if (m_reader->name() == "TravelTime") {
                maneuverContainter.maneuver.setTimeToNextInstruction(qRound(m_reader->readElementText().toDouble()));
            } else if (m_reader->name() == "Length") {
                maneuverContainter.maneuver.setDistanceToNextInstruction(m_reader->readElementText().toDouble());
            } else if (m_reader->name() == "Direction") {
                QString value = m_reader->readElementText();
                if (value == "forward")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionForward);
                else if (value == "bearRight")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionBearRight);
                else if (value == "lightRight")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionLightRight);
                else if (value == "right")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionRight);
                else if (value == "hardRight")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionHardRight);
                else if (value == "uTurnRight")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionUTurnRight);
                else if (value == "uTurnLeft")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionUTurnLeft);
                else if (value == "hardLeft")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionHardLeft);
                else if (value == "left")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionLeft);
                else if (value == "lightLeft")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionLightLeft);
                else if (value == "bearLeft")
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::DirectionBearLeft);
                else
                    maneuverContainter.maneuver.setDirection(QGeoManeuver::NoDirection);
            } else {
                m_reader->skipCurrentElement();
            }
        }
        m_reader->readNext();
    }

    if (m_reader->hasError())
        return false;

    maneuvers.append(maneuverContainter);
    return true;
}

bool QGeoRouteXmlParser::parseLink(QList<QGeoRouteSegmentContainer> &links)
{
    Q_ASSERT(m_reader->isStartElement() && m_reader->name() == QStringLiteral("Link"));
    m_reader->readNext();

    QGeoRouteSegmentContainer segmentContainer;

    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement && m_reader->name() == QStringLiteral("Link")) &&
           !m_reader->hasError()) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            if (m_reader->name() == QStringLiteral("LinkId")) {
                segmentContainer.id = m_reader->readElementText();
            } else if (m_reader->name() == QStringLiteral("Shape")) {
                QString elementName = m_reader->name().toString();
                QList<QGeoCoordinate> path;
                parseGeoPoints(m_reader->readElementText(), &path, elementName);
                segmentContainer.segment.setPath(path);
            } else if (m_reader->name() == QStringLiteral("Length")) {
                segmentContainer.segment.setDistance(m_reader->readElementText().toDouble());
            } else if (m_reader->name() == QStringLiteral("Maneuver")) {
                segmentContainer.maneuverId = m_reader->readElementText();
            } else if (m_reader->name() == QStringLiteral("DynamicSpeedInfo")) {
                QGeoDynamicSpeedInfoContainer speedInfo;
                if (!parseDynamicSpeedInfo(speedInfo))
                    return false;
                const double time = speedInfo.trafficTime >= 0 ? speedInfo.trafficTime : speedInfo.baseTime;
                if (time >= 0)
                    segmentContainer.segment.setTravelTime(time);
            } else {
                m_reader->skipCurrentElement();
            }
        }
        m_reader->readNext();
    }

    if (m_reader->hasError())
        return false;
    links.append(segmentContainer);
    return true;
}

bool QGeoRouteXmlParser::parseGeoPoints(const QString &strPoints, QList<QGeoCoordinate> *geoPoints, const QString &elementName)
{
    QStringList rawPoints = strPoints.split(' ');

    for (int i = 0; i < rawPoints.length(); ++i) {
        QStringList coords = rawPoints[i].split(',');

        if (coords.length() != 2) {
            m_reader->raiseError(QString("Each of the space separated values of \"%1\" is expected to be a comma separated pair of coordinates (value was \"%2\")").arg(elementName).arg(rawPoints[i]));
            return false;
        }

        bool ok = false;
        QString latString = coords[0];
        double lat = latString.toDouble(&ok);

        if (!ok) {
            m_reader->raiseError(QString("The latitude portions of \"%1\" are expected to have a value convertable to a double (value was \"%2\")").arg(elementName).arg(latString));
            return false;
        }

        QString lngString = coords[1];
        double lng = lngString.toDouble(&ok);

        if (!ok) {
            m_reader->raiseError(QString("The longitude portions of \"%1\" are expected to have a value convertable to a double (value was \"%2\")").arg(elementName).arg(lngString));
            return false;
        }

        QGeoCoordinate geoPoint(lat, lng);
        geoPoints->append(geoPoint);
    }

    return true;
}

bool QGeoRouteXmlParser::parseBoundingBox(QGeoRectangle &bounds)
{
    Q_ASSERT(m_reader->isStartElement() && m_reader->name() == "BoundingBox");

    QGeoCoordinate tl;
    QGeoCoordinate br;

    m_reader->readNext();
    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement && m_reader->name() == "BoundingBox") &&
           !m_reader->hasError()) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            if (m_reader->name() == "TopLeft") {
                QGeoCoordinate coordinates;
                if (parseCoordinates(coordinates))
                    tl = coordinates;
            } else if (m_reader->name() == "BottomRight") {
                QGeoCoordinate coordinates;
                if (parseCoordinates(coordinates))
                    br = coordinates;
            } else {
                m_reader->skipCurrentElement();
            }
        }
        m_reader->readNext();
    }

    if (m_reader->hasError())
        return false;

    if (tl.isValid() && br.isValid()) {
        bounds = QGeoRectangle(tl, br);
        return true;
    }

    return false;
}

bool QGeoRouteXmlParser::parseDynamicSpeedInfo(QGeoDynamicSpeedInfoContainer &speedInfo)
{
    Q_ASSERT(m_reader->isStartElement() && m_reader->name() == QStringLiteral("DynamicSpeedInfo"));

    m_reader->readNext();
    while (!(m_reader->tokenType() == QXmlStreamReader::EndElement && m_reader->name() == QStringLiteral("DynamicSpeedInfo")) &&
           !m_reader->hasError()) {
        if (m_reader->tokenType() == QXmlStreamReader::StartElement) {
            if (m_reader->name() == QStringLiteral("TrafficSpeed")) {
                speedInfo.trafficSpeed = m_reader->readElementText().toDouble();
            } else if (m_reader->name() == QStringLiteral("TrafficTime")) {
                speedInfo.trafficTime = qRound(m_reader->readElementText().toDouble());
            } else if (m_reader->name() == QStringLiteral("BaseSpeed")) {
                speedInfo.baseSpeed = m_reader->readElementText().toDouble();
            } else if (m_reader->name() == QStringLiteral("BaseTime")) {
                speedInfo.baseTime = qRound(m_reader->readElementText().toDouble());
            } else {
                m_reader->skipCurrentElement();
            }
        }
        m_reader->readNext();
    }

    return !m_reader->hasError();
}

QT_END_NAMESPACE