/*
 * © Copyright 2014 – Urheberrechtshinweis
 * Alle Rechte vorbehalten / All Rights Reserved
 *
 * Programmcode ist urheberrechtlich geschuetzt.
 * Das Urheberrecht liegt, soweit nicht ausdruecklich anders gekennzeichnet, bei Frank Ebner.
 * Keine Verwendung ohne explizite Genehmigung.
 * (vgl. § 106 ff UrhG / § 97 UrhG)
 */

#ifndef WIFIMEASUREMENT_H
#define WIFIMEASUREMENT_H

#include "AccessPoint.h"
#include "../../data/Timestamp.h"

/**
 * describes a measurement received for one access-point at a given time
 */
class WiFiMeasurement {

private:

	friend class VAPGrouper;

	/** the access-point we got a measurement for */
	AccessPoint ap;

	/** the measured signal strength */
	float rssi;

    /** FTM: estimated distance in m **/
    float distance = NAN;

    /** FTM: standard deviation of estimated distance in m. Only valid if numSuccessfulMeasurements >= 2 **/
    float distanceStdDev = NAN;

    /** FTM: The number of attempted measurements used in the RTT exchange  **/
    int numAttemptedMeasurements = 0;

    /** FTM: The number of successful measurements used to calculate the distance and standard deviation **/
    int numSuccessfulMeasurements = 0;
    
	/** OPTIONAL. frequence the signal was received */
	float freq = NAN;

	/** OPTIONAL. timestamp the measurement was recorded at */
	Timestamp ts;

public:

	/** ctor */
	WiFiMeasurement(const AccessPoint& ap, const float rssi) : ap(ap), rssi(rssi), freq(NAN) {
		;
	}

	/** ctor with freq*/
	WiFiMeasurement(const AccessPoint& ap, const float rssi, const float freq) : ap(ap), rssi(rssi), freq(freq) {
			;
	}

	/** ctor with timestamp */
	WiFiMeasurement(const AccessPoint& ap, const float rssi, const Timestamp ts) : ap(ap), rssi(rssi), freq(NAN), ts(ts) {
			;
	}

    /** ctor with timestamp and ftm */
    WiFiMeasurement(const AccessPoint& ap, const float rssi, const Timestamp ts, const float distance, const float distanceStdDev, const int numAttemptedMeasurements, const int numSuccessfulMeasurements) 
        : ap(ap), rssi(rssi), freq(NAN), ts(ts), distance(distance), distanceStdDev(distanceStdDev), numAttemptedMeasurements(numAttemptedMeasurements), numSuccessfulMeasurements(numSuccessfulMeasurements) {
        ;
    }

	/** ctor with timestamp and freq*/
	WiFiMeasurement(const AccessPoint& ap, const float rssi, const float freq, const Timestamp ts) : ap(ap), rssi(rssi), freq(freq), ts(ts) {
			;
	}

public:

	/** get the AP we got the measurement for */
	const AccessPoint& getAP() const {return ap;}

	/** get the measurement's signal strength */
	float getRSSI() const {return rssi;}

	/** OPTIONAL: get the measurement's timestamp (if known!) */
	const Timestamp& getTimestamp() const {return ts;}

    float getFtmDist() const { return distance; }
    float getFtmDistStd() const { return distanceStdDev; }

    int getNumAttemptedMeasurements() const { return numAttemptedMeasurements; }
    int getNumSuccessfulMeasurements() const { return numSuccessfulMeasurements; }

	/** timestamp known? */
	bool hasTimestamp() const {return ts == ts;}

	/** OPTIONAL: get the measurement's frequency (if known!) */
	float getFrequency() const {return freq;}

	/** frequency known? */
	bool hasFrequency() const {return freq == freq;}

	/** set another signal strength */
	void setRssi(float value){rssi = value;}

	/** set the timestamp */
	void setTimestamp(const Timestamp& val){ts = val;}

    void setFtmDist(float val) { distance = val; }

	/** as string for debug printing */
	std::string asString() const {
		std::string res = ap.asString();
		if (hasTimestamp()) {res += " @" + std::to_string(ts.ms());}
		if (hasFrequency()) {res += " " + std::to_string((int)freq) + " MHz";}
		res += " - " + std::to_string(rssi) + " dBm ";
		return res;
	}

};



#endif // WIFIMEASUREMENT_H