#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Bounce2.h>
#include <Ticker.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define BTN 13


Adafruit_SSD1306 display(SCREEN_WIDTH,SCREEN_HEIGHT,&Wire,-1);

char dataIn;
float circumfrance = 1.2767;
int prevTime;
int timeout;
float time;
float v;
int cnt;
bool messageEnd = true;
Bounce btn = Bounce();
Bounce safe = Bounce();
static float safedData[60];
int sDLength = sizeof(safedData)/sizeof(safedData[0]);
int speicherPos = 0;
bool nullen = false;

void arrayNullen ()
{
  for (int i = 0; i <= sDLength;i++)
  {
    safedData[i] = 0;
  }
}

void werteSpeichern (float v)
{
  safedData[speicherPos] = v;
  speicherPos++;
  if (speicherPos >= 60)
  {
    speicherPos = 0;
  }
}

void anzeigen (float v)
{
  display.clearDisplay();
  display.setCursor(0,10);
  display.print("km/h:");
  display.setCursor(0,40);
  display.print(v);
  display.display();
}

void vMessen ()
{
  nullen = false;
  if (prevTime > 0)
  {
    timeout = millis();
    time = (float)(millis()-prevTime)/1000;
    v = circumfrance/time*3.6;
    anzeigen(v);
    //Serial.println(speicherPos);
    werteSpeichern(v);
  }
  prevTime = millis();
}

void vRuecksetzen()
{
  if (millis()-prevTime > 6000 && !nullen)
  {
    v = 0;
    anzeigen(v);
    werteSpeichern(v);
    nullen = true;
  }
}

void arrayAusgeben ()
{
  for (int j = 0; j < 60; j++)
    {
      Serial.println(safedData[j]);
    }
}

Ticker t1(vMessen, 10);
Ticker t2(vRuecksetzen,100);
Ticker t3(arrayAusgeben,1000);

void setup() 
{
  Serial.begin(9600);

  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.clearDisplay();
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.setCursor(0,10);
  btn.attach( BTN ,  INPUT_PULLUP ); 
  btn.interval(10);
  safe.attach( 12 ,  INPUT_PULLUP ); 
  safe.interval(10);
  t1.start();
  t2.start();
  t3.start();
  arrayNullen ();
}

void loop() 
{
  btn.update();
  safe.update();
  if (btn.fell())
  {
    t1.update();
  }
  t2.update();
  if (safe.fell())
  {
    t3.update();
  }
}