mMDT5_GreenWatch/app/src/main/java/com/example/greenwatch/sensors/AccelerometerSensor.java

package com.example.greenwatch.sensors;

import androidx.lifecycle.MutableLiveData;

import java.util.ArrayList;

public class AccelerometerSensor {
    private MutableLiveData<Boolean> mAccelerometerAlarmDetected = new MutableLiveData<>();
    private static AccelerometerSensor accelerometerSensorInstance;
    private boolean accelerometerAlarmDetected;
    private ArrayList<Float> Gesamt_be;
    int arraySize = 500;
    int functionCallCount;
    float meanValue;
    float offsetValue;
    float thresholdValue;
    boolean startMeasuring;

    private AccelerometerSensor() {
        initGesamtBE();
        accelerometerAlarmDetected = false;
        setMutableLiveDataAccelerometerAlarmDetected();
        functionCallCount = 0;
        meanValue = 0.0f;
        offsetValue = 0.1f;
        thresholdValue = 0.15f;
        startMeasuring = false;
    }

    public static synchronized AccelerometerSensor getInstance() {
        if (accelerometerSensorInstance == null){
            accelerometerSensorInstance = new AccelerometerSensor();
        }
        return accelerometerSensorInstance;
    }

    public MutableLiveData<Boolean> getAccelerometerAlarmDetected() {
        setMutableLiveDataAccelerometerAlarmDetected();
        return mAccelerometerAlarmDetected;
    }

    private void setMutableLiveDataAccelerometerAlarmDetected() {
        mAccelerometerAlarmDetected.setValue(accelerometerAlarmDetected);
    }

    private void initGesamtBE() {
        Gesamt_be = new ArrayList<>(arraySize);
        for (int i = 0; i < arraySize; i++) {
            Gesamt_be.add(0.0f);
        }
    }

    public void addValueToGesamtBE(float newValue) {
        if (Gesamt_be.size() == arraySize) {
            Gesamt_be.remove(Gesamt_be.size() -1);
        }
        Gesamt_be.add(0, newValue);
        functionCallCount++;
    }

    public void meanValueCalculation() {
        for (float element : Gesamt_be) {
            meanValue += Math.abs(element);
        }
        meanValue = meanValue/arraySize;
    }

    public void calibrateAccelerometerSensor() {
        if (functionCallCount <= arraySize) {
            offsetValue = meanValue;
        }
        else {
            startMeasuring = true;
        }
    }

    public void checkAlarmCondition() {
        if (meanValue > (thresholdValue + offsetValue) && startMeasuring && !mAccelerometerAlarmDetected.getValue()) {
            mAccelerometerAlarmDetected.setValue(true);
        }
        else if (meanValue < (thresholdValue + offsetValue) && mAccelerometerAlarmDetected.getValue()){
            mAccelerometerAlarmDetected.setValue(false);
        }
    }

    public float getAccelerometerSensorMeanValue() {
        return meanValue;
    }
}