/****************************************************************************
 *
 *   (c) 2009-2016 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
 *
 * QGroundControl is licensed according to the terms in the file
 * COPYING.md in the root of the source code directory.
 *
 ****************************************************************************/

#pragma once

#include <QObject>
#include <QString>
#include <QtQml>
#include <QTextStream>
#include <QJsonObject>
#include <QGeoCoordinate>

#include "QGCMAVLink.h"
#include "QGC.h"
#include "MavlinkQmlSingleton.h"
#include "QmlObjectListModel.h"
#include "Fact.h"
#include "QGCLoggingCategory.h"
#include "QmlObjectListModel.h"
#include "Vehicle.h"
#include "MissionController.h"

class MissionItem;

// Abstract base class for all Simple and Complex visual mission objects.
class VisualMissionItem : public QObject
{
    Q_OBJECT

public:
    VisualMissionItem(Vehicle* vehicle, QObject* parent = NULL);
    VisualMissionItem(const VisualMissionItem& other, QObject* parent = NULL);

    ~VisualMissionItem();

    const VisualMissionItem& operator=(const VisualMissionItem& other);

    Q_PROPERTY(bool             homePosition                        READ homePosition                                                   CONSTANT)                                           ///< true: This item is being used as a home position indicator
    Q_PROPERTY(QGeoCoordinate   coordinate                          READ coordinate                         WRITE setCoordinate         NOTIFY coordinateChanged)                           ///< This is the entry point for a waypoint line into the item. For a simple item it is also the location of the item
    Q_PROPERTY(double           terrainAltitude                     READ terrainAltitude                                                NOTIFY terrainAltitudeChanged)                      ///< The altitude of terrain at the coordinate position, NaN if not known
    Q_PROPERTY(bool             coordinateHasRelativeAltitude       READ coordinateHasRelativeAltitude                                  NOTIFY coordinateHasRelativeAltitudeChanged)        ///< true: coordinate.latitude is relative to home altitude
    Q_PROPERTY(QGeoCoordinate   exitCoordinate                      READ exitCoordinate                                                 NOTIFY exitCoordinateChanged)                       ///< This is the exit point for a waypoint line coming out of the item.
    Q_PROPERTY(bool             exitCoordinateHasRelativeAltitude   READ exitCoordinateHasRelativeAltitude                              NOTIFY exitCoordinateHasRelativeAltitudeChanged)    ///< true: coordinate.latitude is relative to home altitude
    Q_PROPERTY(bool             exitCoordinateSameAsEntry           READ exitCoordinateSameAsEntry                                      NOTIFY exitCoordinateSameAsEntryChanged)            ///< true: exitCoordinate and coordinate are the same value
    Q_PROPERTY(QString          commandDescription                  READ commandDescription                                             NOTIFY commandDescriptionChanged)
    Q_PROPERTY(QString          commandName                         READ commandName                                                    NOTIFY commandNameChanged)
    Q_PROPERTY(QString          abbreviation                        READ abbreviation                                                   NOTIFY abbreviationChanged)
    Q_PROPERTY(bool             dirty                               READ dirty                              WRITE setDirty              NOTIFY dirtyChanged)                                ///< Item is dirty and requires save/send
    Q_PROPERTY(bool             isCurrentItem                       READ isCurrentItem                      WRITE setIsCurrentItem      NOTIFY isCurrentItemChanged)
    Q_PROPERTY(int              sequenceNumber                      READ sequenceNumber                     WRITE setSequenceNumber     NOTIFY sequenceNumberChanged)
    Q_PROPERTY(int              lastSequenceNumber                  READ lastSequenceNumber                                             NOTIFY lastSequenceNumberChanged)
    Q_PROPERTY(bool             specifiesCoordinate                 READ specifiesCoordinate                                            NOTIFY specifiesCoordinateChanged)                  ///< true: Item is associated with a coordinate position
    Q_PROPERTY(bool             isStandaloneCoordinate              READ isStandaloneCoordinate                                         NOTIFY isStandaloneCoordinateChanged)               ///< true: Waypoint line does not go through item
    Q_PROPERTY(bool             specifiesAltitudeOnly               READ specifiesAltitudeOnly                                          NOTIFY specifiesAltitudeOnlyChanged)                ///< true: Item has altitude only, no full coordinate
    Q_PROPERTY(bool             isSimpleItem                        READ isSimpleItem                                                   NOTIFY isSimpleItemChanged)                         ///< Simple or Complex MissionItem
    Q_PROPERTY(QString          editorQml                           MEMBER _editorQml                                                   CONSTANT)                                           ///< Qml code for editing this item
    Q_PROPERTY(QString          mapVisualQML                        READ mapVisualQML                                                   CONSTANT)                                           ///< QMl code for map visuals
    Q_PROPERTY(QmlObjectListModel* childItems                       READ childItems                                                     CONSTANT)
    Q_PROPERTY(double           specifiedFlightSpeed                READ specifiedFlightSpeed                                           NOTIFY specifiedFlightSpeedChanged)                 ///< NaN if this item does not specify flight speed
    Q_PROPERTY(double           specifiedGimbalYaw                  READ specifiedGimbalYaw                                             NOTIFY specifiedGimbalYawChanged)                   ///< Gimbal yaw, NaN for not specified
    Q_PROPERTY(double           specifiedGimbalPitch                READ specifiedGimbalPitch                                           NOTIFY specifiedGimbalPitchChanged)                 ///< Gimbal pitch, NaN for not specified
    Q_PROPERTY(double           missionGimbalYaw                    READ missionGimbalYaw                                               NOTIFY missionGimbalYawChanged)                     ///< Current gimbal yaw state at this point in mission
    Q_PROPERTY(double           missionVehicleYaw                   READ missionVehicleYaw                                              NOTIFY missionVehicleYawChanged)                    ///< Expected vehicle yaw at this point in mission

    // The following properties are calculated/set by the MissionController recalc methods

    Q_PROPERTY(double altDifference     READ altDifference      WRITE setAltDifference      NOTIFY altDifferenceChanged)        ///< Change in altitude from previous waypoint
    Q_PROPERTY(double altPercent        READ altPercent         WRITE setAltPercent         NOTIFY altPercentChanged)           ///< Percent of total altitude change in mission altitude
    Q_PROPERTY(double terrainPercent    READ terrainPercent     WRITE setTerrainPercent     NOTIFY terrainPercentChanged)       ///< Percent of terrain altitude in mission altitude
    Q_PROPERTY(double azimuth           READ azimuth            WRITE setAzimuth            NOTIFY azimuthChanged)              ///< Azimuth to previous waypoint
    Q_PROPERTY(double distance          READ distance           WRITE setDistance           NOTIFY distanceChanged)             ///< Distance to previous waypoint

    // Property accesors

    bool homePosition               (void) const { return _homePositionSpecialCase; }
    void setHomePositionSpecialCase (bool homePositionSpecialCase) { _homePositionSpecialCase = homePositionSpecialCase; }

    double altDifference    (void) const { return _altDifference; }
    double altPercent       (void) const { return _altPercent; }
    double terrainPercent   (void) const { return _terrainPercent; }
    double azimuth          (void) const { return _azimuth; }
    double distance         (void) const { return _distance; }
    bool   isCurrentItem    (void) const { return _isCurrentItem; }
    double terrainAltitude  (void) const { return _terrainAltitude; }

    QmlObjectListModel* childItems(void) { return &_childItems; }

    void setIsCurrentItem   (bool isCurrentItem);
    void setAltDifference   (double altDifference);
    void setAltPercent      (double altPercent);
    void setTerrainPercent  (double terrainPercent);
    void setAzimuth         (double azimuth);
    void setDistance        (double distance);

    Vehicle* vehicle(void) { return _vehicle; }

    // Pure virtuals which must be provides by derived classes

    virtual bool            dirty                   (void) const = 0;
    virtual bool            isSimpleItem            (void) const = 0;
    virtual bool            isStandaloneCoordinate  (void) const = 0;
    virtual bool            specifiesCoordinate     (void) const = 0;
    virtual bool            specifiesAltitudeOnly   (void) const = 0;
    virtual QString         commandDescription      (void) const = 0;
    virtual QString         commandName             (void) const = 0;
    virtual QString         abbreviation            (void) const = 0;
    virtual QGeoCoordinate  coordinate              (void) const = 0;
    virtual QGeoCoordinate  exitCoordinate          (void) const = 0;
    virtual int             sequenceNumber          (void) const = 0;
    virtual double          specifiedFlightSpeed    (void) = 0;
    virtual double          specifiedGimbalYaw      (void) = 0;
    virtual double          specifiedGimbalPitch    (void) = 0;

    /// Update item to mission flight status at point where this item appears in mission.
    /// IMPORTANT: Overrides must call base class implementation
    virtual void setMissionFlightStatus(MissionController::MissionFlightStatus_t& missionFlightStatus);

    virtual bool coordinateHasRelativeAltitude      (void) const = 0;
    virtual bool exitCoordinateHasRelativeAltitude  (void) const = 0;
    virtual bool exitCoordinateSameAsEntry          (void) const = 0;

    virtual void setDirty           (bool dirty) = 0;
    virtual void setCoordinate      (const QGeoCoordinate& coordinate) = 0;
    virtual void setSequenceNumber  (int sequenceNumber) = 0;
    virtual int  lastSequenceNumber (void) const = 0;

    /// Specifies whether the item has all the data it needs such that it can be saved. Currently the only
    /// case where this returns false is if it has not determined terrain values yet.
    /// @return true: Ready to save, false: Still waiting on information
    virtual bool readyForSave(void) const { return true; }

    /// Save the item(s) in Json format
    ///     @param missionItems Current set of mission items, new items should be appended to the end
    virtual void save(QJsonArray&  missionItems) = 0;

    /// @return The QML resource file which contains the control which visualizes the item on the map.
    virtual QString mapVisualQML(void) const = 0;

    /// Returns the mission items associated with the complex item. Caller is responsible for freeing.
    ///     @param items List to append to
    ///     @param missionItemParent Parent object for newly created MissionItems
    virtual void appendMissionItems(QList<MissionItem*>& items, QObject* missionItemParent) = 0;

    /// Adjust the altitude of the item if appropriate to the new altitude.
    virtual void applyNewAltitude(double newAltitude) = 0;

    double  missionGimbalYaw    (void) const { return _missionGimbalYaw; }
    double  missionVehicleYaw   (void) const { return _missionVehicleYaw; }
    void    setMissionVehicleYaw(double vehicleYaw);

    static const char* jsonTypeKey;                 ///< Json file attribute which specifies the item type
    static const char* jsonTypeSimpleItemValue;     ///< Item type is MISSION_ITEM
    static const char* jsonTypeComplexItemValue;    ///< Item type is Complex Item

signals:
    void altDifferenceChanged           (double altDifference);
    void altPercentChanged              (double altPercent);
    void terrainPercentChanged          (double terrainPercent);
    void azimuthChanged                 (double azimuth);
    void commandDescriptionChanged      (void);
    void commandNameChanged             (void);
    void abbreviationChanged            (void);
    void coordinateChanged              (const QGeoCoordinate& coordinate);
    void exitCoordinateChanged          (const QGeoCoordinate& exitCoordinate);
    void dirtyChanged                   (bool dirty);
    void distanceChanged                (double distance);
    void isCurrentItemChanged           (bool isCurrentItem);
    void sequenceNumberChanged          (int sequenceNumber);
    void isSimpleItemChanged            (bool isSimpleItem);
    void specifiesCoordinateChanged     (void);
    void isStandaloneCoordinateChanged  (void);
    void specifiesAltitudeOnlyChanged   (void);
    void specifiedFlightSpeedChanged    (void);
    void specifiedGimbalYawChanged      (void);
    void specifiedGimbalPitchChanged    (void);
    void lastSequenceNumberChanged      (int sequenceNumber);
    void missionGimbalYawChanged        (double missionGimbalYaw);
    void missionVehicleYawChanged       (double missionVehicleYaw);
    void terrainAltitudeChanged         (double terrainAltitude);

    void coordinateHasRelativeAltitudeChanged       (bool coordinateHasRelativeAltitude);
    void exitCoordinateHasRelativeAltitudeChanged   (bool exitCoordinateHasRelativeAltitude);
    void exitCoordinateSameAsEntryChanged           (bool exitCoordinateSameAsEntry);

protected:
    Vehicle*    _vehicle;
    bool        _isCurrentItem;
    bool        _dirty;
    bool        _homePositionSpecialCase;   ///< true: This item is being used as a ui home position indicator
    double      _terrainAltitude;           ///< Altitude of terrain at coordinate position, NaN for not known
    double      _altDifference;             ///< Difference in altitude from previous waypoint
    double      _altPercent;                ///< Percent of total altitude change in mission
    double      _terrainPercent;            ///< Percent of terrain altitude for coordinate
    double      _azimuth;                   ///< Azimuth to previous waypoint
    double      _distance;                  ///< Distance to previous waypoint
    QString     _editorQml;                 ///< Qml resource for editing item
    double      _missionGimbalYaw;
    double      _missionVehicleYaw;

    MissionController::MissionFlightStatus_t    _missionFlightStatus;

    /// This is used to reference any subsequent mission items which do not specify a coordinate.
    QmlObjectListModel  _childItems;

private slots:
    void _updateTerrainAltitude (void);
    void _reallyUpdateTerrainAltitude (void);
    void _terrainDataReceived   (bool success, QList<float> altitudes);

private:
    QTimer _updateTerrainTimer;
    double _lastLatTerrainQuery;
    double _lastLonTerrainQuery;
};