/****************************************************************************/
// Eclipse SUMO, Simulation of Urban MObility; see https://eclipse.org/sumo
// Copyright (C) 2003-2019 German Aerospace Center (DLR) and others.
// This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v2.0
// which accompanies this distribution, and is available at
// http://www.eclipse.org/legal/epl-v20.html
// SPDX-License-Identifier: EPL-2.0
/****************************************************************************/
/// @file    MSE3Collector.h
/// @author  Christian Roessel
/// @author  Daniel Krajzewicz
/// @author  Michael Behrisch
/// @author  Jakob Erdmann
/// @date    Tue Dec 02 2003 22:17 CET
/// @version $Id$
///
// A detector of vehicles passing an area between entry/exit points
/****************************************************************************/
#ifndef MSE3Collector_h
#define MSE3Collector_h


// ===========================================================================
// included modules
// ===========================================================================
#include <config.h>

#include <string>
#include <vector>
#include <limits>
#include <microsim/MSMoveReminder.h>
#include <microsim/output/MSDetectorFileOutput.h>
#include <utils/common/Named.h>
#include <microsim/output/MSCrossSection.h>
#include <utils/common/UtilExceptions.h>


// ===========================================================================
// class declarations
// ===========================================================================
class SUMOTrafficObject;
class OutputDevice;


// ===========================================================================
// class definitions
// ===========================================================================
/**
 * @class MSE3Collector
 * @brief A detector of vehicles passing an area between entry/exit points
 *
 * E3 detectors are defined by a set of in-cross-sections and out-cross-sections.
 * Vehicles, that pass an in- and out-cross-section are detected when they pass the
 *  out-cross-section. Vehicles passing the out-cross-section without having
 *  passed the in-cross-section are not detected.
 */
class MSE3Collector : public MSDetectorFileOutput {
public:
    /**
     * @class MSE3EntryReminder
     * @brief A place on the road net (at a certain lane and position on it) where the E3 area begins
     */
    class MSE3EntryReminder : public MSMoveReminder {
    public:
        /** @brief Constructor
         *
         * @param[in] crossSection The position at which the entry lies
         * @param[in] collector The detector the entry belongs to
         */
        MSE3EntryReminder(const MSCrossSection& crossSection, MSE3Collector& collector);


        /// @name Methods inherited from MSMoveReminder.
        /// @{
        /** @brief Checks whether the reminder is activated by a vehicle entering the lane
         *
         * Lane change means in this case that the vehicle changes to the lane
         *  the reminder is placed at.
         *
         * @param[in] veh The entering vehicle.
         * @param[in] reason how the vehicle enters the lane
         * @return True if vehicle enters the reminder.
         * @see Notification
         */
        bool notifyEnter(SUMOTrafficObject& veh, Notification reason, const MSLane* enteredLane);

        /** @brief Checks whether the vehicle enters
         *
         * As soon as the reported vehicle enters the detector area (position>myPosition)
         *  the entering time is computed and both are added to the parent detector using
         *  "enter".
         *
         * @param[in] veh The vehicle in question.
         * @param[in] oldPos Position before the move-micro-timestep.
         * @param[in] newPos Position after the move-micro-timestep.
         * @param[in] newSpeed Unused here.
         * @return False, if vehicle passed the detector entierly, else true.
         * @see MSMoveReminder
         * @see MSMoveReminder::notifyMove
         * @see MSE3Collector::enter
         */
        bool notifyMove(SUMOTrafficObject& veh, double, double newPos, double);


        /** @brief Processes state changes of a vehicle
        *
        * If the reported vehicle is known, and the reason indicates a removal from the network
        *  (permanent or temporary), the vehicle is removed from the list of vehicles to regard.
        *
        * @param[in] veh The leaving vehicle.
        * @param[in] lastPos Position on the lane when leaving.
        * @param[in] reason The reason for the state change
        * @see MSMoveReminder::notifyLeave
        */
        bool notifyLeave(SUMOTrafficObject& veh, double lastPos, MSMoveReminder::Notification reason, const MSLane* enteredLane = 0);
        /// @}


    private:
        /// @brief The parent collector
        MSE3Collector& myCollector;

        /// @brief The position on the lane
        double myPosition;

    private:
        /// @brief Invalidated copy constructor.
        MSE3EntryReminder(const MSE3EntryReminder&);

        /// @brief Invalidated assignment operator.
        MSE3EntryReminder& operator=(const MSE3EntryReminder&);

    };



    /**
     * @class MSE3LeaveReminder
     * @brief A place on the road net (at a certain lane and position on it) where the E3 area ends
     */
    class MSE3LeaveReminder : public MSMoveReminder {
    public:
        /** @brief Constructor
         *
         * @param[in] crossSection The position at which the exit lies
         * @param[in] collector The detector the exit belongs to
         */
        MSE3LeaveReminder(const MSCrossSection& crossSection, MSE3Collector& collector);


        /// @name methods from MSMoveReminder
        //@{
        /** @brief Checks whether the reminder is activated by a vehicle entering the lane
         *
         * Lane change means in this case that the vehicle changes to the lane
         *  the reminder is placed at.
         *
         * @param[in] veh The entering vehicle.
         * @param[in] reason how the vehicle enters the lane
         * @return True if vehicle enters the reminder.
         * @see Notification
         */
        bool notifyEnter(SUMOTrafficObject& veh, Notification reason, const MSLane* enteredLane);

        /** @brief Checks whether the vehicle leaves
         *
         * As soon as the reported vehicle leaves the detector area (position-length>myPosition)
         *  the leaving time is computed and both are made known to the parent detector using
         *  "leave".
         *
         * @param[in] veh The vehicle in question.
         * @param[in] oldPos Position before the move-micro-timestep.
         * @param[in] newPos Position after the move-micro-timestep.
         * @param[in] newSpeed Unused here.
         * @return False, if vehicle passed the detector entirely, else true.
         * @see MSMoveReminder
         * @see MSMoveReminder::notifyMove
         * @see MSE3Collector::leave
         */
        bool notifyMove(SUMOTrafficObject& veh, double oldPos, double newPos, double);

        /** @brief Processes state changes of a vehicle
        *
        * Checks whether the vehicle has changed lanes and this reminder needs to be removed
        *
        * @param[in] veh The leaving vehicle (unused).
        * @param[in] lastPos Position on the lane when leaving (unused).
        * @param[in] reason The reason for the state change
        * @see MSMoveReminder::notifyLeave
        */
        bool notifyLeave(SUMOTrafficObject& veh, double lastPos, MSMoveReminder::Notification reason, const MSLane* enteredLane = 0);
        //@}


    private:
        /// @brief The parent collector
        MSE3Collector& myCollector;

        /// @brief The position on the lane
        double myPosition;

    private:
        /// @brief Invalidated copy constructor.
        MSE3LeaveReminder(const MSE3LeaveReminder&);

        /// @brief Invalidated assignment operator.
        MSE3LeaveReminder& operator=(const MSE3LeaveReminder&);

    };


    /** @brief Constructor
     *
     * Sets reminder objects on entry- and leave-lanes
     *
     *  @param[in] id The detector's unique id.
     *  @param[in] entries Entry-cross-sections.
     *  @param[in] exits Leavey-cross-sections.
     *  @param[in] haltingSpeedThreshold A vehicle must not drive a greater speed than haltingSpeedThreshold to be a "halting" vehicle.
     *  @param[in] haltingTimeThreshold A vehicle must not drive a greater speed for more than haltingTimeThreshold to be a "halting" vehicle.
     */
    MSE3Collector(const std::string& id,
                  const CrossSectionVector& entries, const CrossSectionVector& exits,
                  double haltingSpeedThreshold,
                  SUMOTime haltingTimeThreshold,
                  const std::string& vTypes, bool openEntry);


    /// @brief Destructor
    virtual ~MSE3Collector();


    /** @brief Resets all generated values to allow computation of next interval
     */
    void reset();


    /** @brief Called if a vehicle touches an entry-cross-section.
     *
     * Inserts vehicle into internal containers.
     *
     *  @param[in] veh The vehicle that entered the area
     *  @param[in] entryTimestep The time in seconds the vehicle entered the area
     *  @param[in] fractionTimeOnDet The interpolated time in seconds the vehicle already spent on the detector
     */
    void enter(const SUMOTrafficObject& veh, const double entryTimestep, const double fractionTimeOnDet, MSE3EntryReminder* entryReminder);


    /** @brief Called if a vehicle front passes a leave-cross-section.
    *
    *  @param[in] veh The vehicle that left the area
    *  @param[in] leaveTimestep The time in seconds the vehicle started crossing the line
    */
    void leaveFront(const SUMOTrafficObject& veh, const double leaveTimestep);


    /** @brief Called if a vehicle back passes a leave-cross-section.
    *
    * Removes vehicle from internal containers.
    *
    *  @param[in] veh The vehicle that left the area
    *  @param[in] leaveTimestep The time in seconds the vehicle left the area
    *  @param[in] fractionTimeOnDet The interpolated time in seconds the vehicle still spent on the detector
    */
    void leave(const SUMOTrafficObject& veh, const double leaveTimestep, const double fractionTimeOnDet);


    /// @name Methods returning current values
    /// @{

    /** @brief Returns the mean speed within the area
     *
     * If no vehicle is within the area, -1 is returned.
     *
     * @return The mean speed [m/s] of all vehicles within the area, -1 if there is none
     */
    double getCurrentMeanSpeed() const;


    /** @brief Returns the number of current haltings within the area
     *
     * If no vehicle is within the area, 0 is returned.
     *
     * @return The mean number of haltings within the area
     */
    int getCurrentHaltingNumber() const;


    /** @brief Returns the number of vehicles within the area
     * @return The number of vehicles that passed the entry collector
     */
    int getVehiclesWithin() const;


    /** @brief Returns the number of vehicles within the area
     *
     * @return The number of vehicles that have passed the entry, but not yet an exit point
     */
    std::vector<std::string> getCurrentVehicleIDs() const;
    /// @}


    /// @name Methods inherited from MSDetectorFileOutput.
    /// @{

    /** @brief Writes collected values into the given stream
     *
     * @param[in] dev The output device to write the data into
     * @param[in] startTime First time step the data were gathered
     * @param[in] stopTime Last time step the data were gathered
     * @see MSDetectorFileOutput::writeXMLOutput
     * @exception IOError If an error on writing occurs (!!! not yet implemented)
     */
    void writeXMLOutput(OutputDevice& dev, SUMOTime startTime, SUMOTime stopTime);


    /** @brief Opens the XML-output using "e3Detector" as root element
     *
     * The lists of entries/exists are written, too.
     *
     * @param[in] dev The output device to write the root into
     * @see MSDetectorFileOutput::writeXMLDetectorProlog
     * @exception IOError If an error on writing occurs (!!! not yet implemented)
     */
    void writeXMLDetectorProlog(OutputDevice& dev) const;
    /// @}



    /** @brief Computes the detector values in each time step
     *
     * This method should be called at the end of a simulation step, when
     *  all vehicles have moved. The current values are computed and
     *  summed up with the previous.
     *
     * @param[in] currentTime The current simulation time (unused)
     */
    void detectorUpdate(const SUMOTime step);


protected:
    /// @brief The detector's entries
    CrossSectionVector myEntries;

    /// @brief The detector's exits
    CrossSectionVector myExits;

    /// @brief The detector's built entry reminder
    std::vector<MSE3EntryReminder*> myEntryReminders;

    /// @brief The detector's built exit reminder
    std::vector<MSE3LeaveReminder*> myLeaveReminders;


    // @brief Time-threshold to determine if a vehicle is halting.
    SUMOTime myHaltingTimeThreshold;

    /// @brief Speed-threshold to determine if a vehicle is halting.
    double myHaltingSpeedThreshold;

    /**
     * @struct E3Values
     * @brief Internal storage for values from a vehicle
     *
     * For each vehicle within the area (that entered through an entry point),
     *  this structure is allocated. All values gathered from the vehicle are aggregated
     *  within this structure.
     */
    struct E3Values {
        /// @brief The vehicle's entry time
        double entryTime;
        /// @brief The time the vehicle's front was crossing the leave line
        double frontLeaveTime;
        /// @brief The time the vehicle's back was crossing the leave line
        double backLeaveTime;
        /// @brief The sum of registered speeds the vehicle has/had inside the area
        double speedSum;
        /// @brief The sum of haltings the vehicle has/had within the area
        int haltings;
        /// @brief Begin time of last halt begin
        SUMOTime haltingBegin;
        /// @brief The sum of registered speeds the vehicle has/had inside the area during the current interval
        double intervalSpeedSum;
        /// @brief The sum of haltings the vehicle has/had within the area during the current interval
        int intervalHaltings;
        /// @brief The timeLoss of the vehicle when entering. Updated to the actual time loss within the area when leaving
        SUMOTime timeLoss;
        /// @brief The timeLoss of the vehicle when entering. Updated to the current timeLoss at interval write
        SUMOTime intervalTimeLoss;
        /// @brief An internal information whether the update step was performed
        bool hadUpdate;
        /// @brief the reminder on which the vehicle entered the detector
        MSE3EntryReminder* entryReminder;
    };

    /// @brief Container for vehicles that have entered the area
    std::map<const SUMOTrafficObject*, E3Values> myEnteredContainer;

    /// @brief Container for vehicles that have left the area
    std::vector<E3Values> myLeftContainer;


    /// @name Storages for current values
    /// @{

    /// @brief The current mean speed of known vehicles (inside)
    double myCurrentMeanSpeed;

    /// @brief The current number of haltings (inside)
    int myCurrentHaltingsNumber;
    /// @}


    /// @brief Information when the last reset has been done
    SUMOTime myLastResetTime;

    /// @brief whether this dector is declared as having incomplete entry detectors
    const bool myOpenEntry;

private:
    /// @brief Invalidated copy constructor.
    MSE3Collector(const MSE3Collector&);

    /// @brief Invalidated assignment operator.
    MSE3Collector& operator=(const MSE3Collector&);


};


#endif

/****************************************************************************/