/*
   Master script combine functions
   -> Rotation measurement
   -> Time reading from RTC
*/
//library includes
#include <RTClib.h>

//library inits
RTC_DS3231 rtc;

//test options
#define SET_RTC_DATE true   //set this to true to initialize the RTC clock with the time of the code upload

//settings that need to be adjusted
#define RADIUS 10           // definiert den Rotorradius in cm

//static settings
#define BAUD 9600
#define REEDPIN 2           //io pin for reed contact (with exterenal 10k pullup resistor to vcc)
#define DEBOUNCETIME 200    //debouncing interval
#define INTERVAL 1000       //calculation interval in which the values get sent to serial


//constant numbers
#define PI 3.1415926535897932384626433832795    // definiere PI

//mapping arrays
char daysOfTheWeek[7][12] = {
  "Sunday",
  "Monday",
  "Tuesday",
  "Wednesday",
  "Thursday",
  "Friday",
  "Saturday"
};

//variables
volatile unsigned int contacts;
volatile unsigned long time_inbetween_interrupts;     // Periodendauer in ms
unsigned long lastmillis;
unsigned int lastcontacts;


void setup() {
  attachInterrupt(digitalPinToInterrupt(REEDPIN), count, FALLING);     // setzt ISR fürs hochzählen
  Serial.begin(BAUD);

  // set up rtc module
  if (! rtc.begin()) {
    Serial.println("Couldn't find RTC");
    Serial.println("halting program, reset to retry");
    Serial.flush();
    while (1);
  }

  //if this is the first time you use the RTC module you can set the time of the module with this function,
  //disable afterwards in the #define of SET_RTC_DATE
  if(SET_RTC_DATE){
    // automatically sets the RTC to the date & time on PC this sketch was compiled
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }
}

void loop() {
  //function runs if the time since the last run is greater than the configured interval
  if (lastmillis + INTERVAL <= millis()) {
    //store time of running the function
    lastmillis = millis();

    //calculations
    float rpm = 1000.0 / time_inbetween_interrupts;
    float rs = (2 * PI * RADIUS) / time_inbetween_interrupts * 10;   // Bahngeschwindigkeitsformel (https://www.leifiphysik.de/mechanik/kreisbewegung/grundwissen/bahngeschwindigkeit-und-winkelgeschwindigkeit)
    float ws = 0.5921 * rpm + 2.3654;     // Windgeschwindigkeit wird berechnet

    //serial outputs
    Serial.println("####################");
    Serial.println("rpm:"+(float)rpm));
    //Serial.print("Drehzahl: ");
    //Serial.println((float)rpm);

    Serial.print("Umdrehungsgeschwindigkeit: ");
    Serial.print((float)rs);
    Serial.println("m/s");

    Serial.print("Kontakte: ");
    Serial.println(contacts);

    Serial.print("Windgeschwindigkeit: ");
    Serial.print((float)ws);
    Serial.println("m/s");

    Serial.println(time_inbetween_interrupts);

    //reset contact counter to 0
    contacts = 0;
    test();
  }
}

void printTime(){
  DateTime now = rtc.now();
  Serial.print("Date & Time: ");
  Serial.print(now.year(), DEC);
  Serial.print('/');
  Serial.print(now.month(), DEC);
  Serial.print('/');
  Serial.print(now.day(), DEC);
  Serial.print(" (");
  Serial.print(daysOfTheWeek[now.dayOfTheWeek()]);
  Serial.print(") ");
  Serial.print(now.hour(), DEC);
  Serial.print(':');
  Serial.print(now.minute(), DEC);
  Serial.print(':');
  Serial.println(now.second(), DEC);
}

//interrupt routine defined in setup
void count() {
  static unsigned long last_interrupt_time = 0;
  unsigned long interrupt_time = millis();
  //skipping impulses if they happen to fast (debouncing)
  if(interrupt_time - last_interrupt_time > DEBOUNCETIME){
    contacts++;     // erhöht die gezählten Kontakte
    time_inbetween_interrupts = interrupt_time - last_interrupt_time;
  }

  last_interrupt_time = interrupt_time;
}