unsigned long ctimeS;
unsigned long ptimeS = 0;
int timeS = 5;
String serial;
#include <string.h>
//leds 7 segment display
#define A 7
#define B 6
#define C 4
#define D 3
#define E 2
#define F 8
#define G 9
#define Dp 5

//7 segment displays
#define display1 10
#define display2 11
#define display3 13
int h;

//buttons
#define change A5
bool Change = false;
int counterCF = 0;
#define plus A3
bool Plus = false;
#define min A2
bool Min = false;
#define buzzer A1
bool Buzzer = false;
float buzzT = 10.0;
//temps
float temp, Temp, NUM, x, BuzzT;

//time
unsigned long ctime, ptime = 0, ctimeC, ptimeC = 0, ctimeF, ptimeF = 0;

//sensor
#define LMT86 A0
float sensorValue;
float voltageC, voltageF;

//serial
int ScounterCF = 0; //counter for switch from celsius to fahreneheit and opposite

//debouncing
unsigned long const debounceDuration = 500; //interval

void setup() {
  // put your setup code here, to run once:
  //Leds segment display
  Serial.begin(9600);
  Serial.setTimeout(10); //this will stop everything in serial to give you, and check, the infromation
  Serial.print("start");
  pinMode(A, OUTPUT);
  pinMode(B, OUTPUT);
  pinMode(C, OUTPUT);
  pinMode(D, OUTPUT);
  pinMode(E, OUTPUT);
  pinMode(F, OUTPUT);
  pinMode(G, OUTPUT);
  pinMode(Dp, OUTPUT);

  //Buttons
  pinMode(change, INPUT);
  pinMode(plus, INPUT);
  pinMode(min, INPUT);
  pinMode(buzzer, INPUT);

  //displays
  pinMode(display1, OUTPUT);
  pinMode(display2, OUTPUT);
  pinMode(display3, OUTPUT);

  celsius();
}

void loop() {
  // put your main code here, to run repeatedly:
  Temp = temp;
  BuzzT = buzzT;
  buttons();
  which();
  tone();

  if (Serial.available() > 0) { //if number of bytes is greater than 0 read the string
    serial = Serial.readStringUntil("\n");
    serial.trim();
    Serial.println(serial);
    //serial.toLowerCase();
    if (serial == "cel") {
      //Celsius
      celsius();
    }
    else if (serial == "fahr") {
      //Fahrenheit
      fahrenheit();
    }
    else if (serial == "threshold") {
      //Switch to threshold changer
      buzzing();
    }
    else if (serial == "plus") {
      //temp +0.5
      buzzing();
    }
    else if (serial == "minus") {
      //temp -0.5
      buzzing();
    }
    else {
      Serial.println("Not a correct string. Choose from cel, fahr, threshold, plus and minus!");
    }
  }
  
}

void buttons() {
  ctime = millis();
  if (ctime - ptime >= debounceDuration) {
    if (digitalRead(change) == true) {
      //change from c to f or f to c
      if (ScounterCF % 2 == 0) {
        celsius();
        ScounterCF++;
        ptime = ctime;
      }
      else if (ScounterCF % 2 == 1) {
        fahrenheit();
        ScounterCF++;
        ptime = ctime;
      }
      Change = true;
      Buzzer = false;
      Plus = false;
      Min = false;
    }
    else if (digitalRead(plus) == true) {
      //increase limit +0,5
      Change = false;
      Plus = true;
      Buzzer = true;
      number(buzzT);
      buzzing();
      ptime = ctime;
    }
    else if (digitalRead(min) == true) {
      //decrease limit -0,5
      Change = false;
      Buzzer = true;
      Min = true;
      number(BuzzT);
      buzzing();
      ptime = ctime;
    }
    else if (digitalRead(buzzer) == true) {
      //do something with the buzzer
      Change = false;
      Buzzer = true;
      number(BuzzT);
      buzzing();
      ptime = ctime;
    }
  }
}

void which() {
  if (((Change == true) && (Buzzer == false)) || serial == "cel" || serial == "fahr") {
    number(Temp);
  }
  else if (((Buzzer == true) && (Change == false)) || serial == "plus" || serial == "minus" || serial == "threshold") {
    number(BuzzT);
    buzzing();
  }
}

void tone() {
  if (buzzT > temp) {
    tone(buzzer, 1000);
  }
  else {
    noTone(buzzer);
  }
}

void buzzing() {
  number(BuzzT);
  if (Plus == true || serial == "plus") {
    buzzT += 0.5;
    number(buzzT);
    Plus = false;
    serial = "threshold";
  }
  else if (Min == true || serial == "minus") {
    buzzT -= 0.5;
    number(buzzT);
    Min = false;
    serial = "threshold";
  }
  else if (Buzzer == true || serial == "threshold") {
    number(buzzT);
  }
}

void celsius() {
  ctimeC = millis();
  if (ctimeC - ptimeC >= debounceDuration) {
    sensorValue = analogRead(LMT86); //read value of analogpin
    voltageC = (sensorValue * 5 / 1024.0) * 1000;
    temp = sqrt(pow(-10.888, 2) + 4 * 0.00347 * (1777.3 - voltageC));
    temp = (10.888 - temp) / (2 * -0.00347);
    temp = temp + 30;
    temp = round(temp * 10);
    temp = temp / 10;
    ptimeC = ctimeC;

    number(temp);
    Serial.print("Temperature in Celsius: ");
    Serial.print(temp);
    Serial.println(" °C");
  }
}

void fahrenheit() {
  ctimeF = millis();
  if (ctimeF - ptimeF >= debounceDuration) {
    sensorValue = analogRead(LMT86); //read value of analogpin
    voltageF = (sensorValue * 5 / 1024.0) * 1000;
    temp = sqrt(pow(-10.888, 2) + 4 * 0.00347 * (1777.3 - voltageF));
    temp = (10.888 - temp) / (2 * -0.00347);
    temp = temp + 30;
    temp = (temp * 9 / 5) + 32;
    temp = round(temp * 10);
    temp = temp / 10;
    ptimeF = ctimeF;

    number(temp);
    Serial.print("Temperature in Fahrenheit: ");
    Serial.print(temp);
    Serial.println(" °F");
  }
}

void number(float x) {
  x = x * 10;
  int NUM = int(x);
  //hecto
  h = NUM / 100;
  digitalWrite(display3, HIGH);
  digitalWrite(Dp, LOW);
  delay(5);
  segments(h);
  digitalWrite(display3, LOW);

  //deca
  h = (NUM % 100) / 10;
  digitalWrite(display1, HIGH);
  digitalWrite(Dp, LOW);
  delay(5);
  segments(h);
  digitalWrite(display1, LOW);

  //integer
  h = NUM % 10;
  digitalWrite(display2, HIGH);
  digitalWrite(Dp, HIGH);
  delay(5);
  segments(h);
  digitalWrite(display2, LOW);

}

void ghost() {
  digitalWrite(A, LOW);
  digitalWrite(B, LOW);
  digitalWrite(C, LOW);
  digitalWrite(D, LOW);
  digitalWrite(E, LOW);
  digitalWrite(F, LOW);
  digitalWrite(G, LOW);
}

void segments(int num) {
  ctimeS = millis();
  if (ctimeS - ptimeS >= timeS) {
    ghost();
    switch (num) {
      case 0:
        digitalWrite(A, HIGH);
        digitalWrite(B, HIGH);
        digitalWrite(C, HIGH);
        digitalWrite(D, HIGH);
        digitalWrite(E, HIGH);
        digitalWrite(F, HIGH);
        digitalWrite(G, LOW);
        break;

      case 1:
        digitalWrite(A, LOW);
        digitalWrite(B, HIGH);
        digitalWrite(C, HIGH);
        digitalWrite(D, LOW);
        digitalWrite(E, LOW);
        digitalWrite(F, LOW);
        digitalWrite(G, LOW);
        break;

      case 2:
        digitalWrite(A, HIGH);
        digitalWrite(B, HIGH);
        digitalWrite(C, LOW);
        digitalWrite(D, HIGH);
        digitalWrite(E, HIGH);
        digitalWrite(F, LOW);
        digitalWrite(G, HIGH);
        break;

      case 3:
        digitalWrite(A, HIGH);
        digitalWrite(B, HIGH);
        digitalWrite(C, HIGH);
        digitalWrite(D, HIGH);
        digitalWrite(E, LOW);
        digitalWrite(F, LOW);
        digitalWrite(G, HIGH);
        break;

      case 4:
        digitalWrite(A, LOW);
        digitalWrite(B, HIGH);
        digitalWrite(C, HIGH);
        digitalWrite(D, LOW);
        digitalWrite(E, LOW);
        digitalWrite(F, HIGH);
        digitalWrite(G, HIGH);
        break;

      case 5:
        digitalWrite(A, HIGH);
        digitalWrite(B, LOW);
        digitalWrite(C, HIGH);
        digitalWrite(D, HIGH);
        digitalWrite(E, LOW);
        digitalWrite(F, HIGH);
        digitalWrite(G, HIGH);
        break;

      case 6:
        digitalWrite(A, HIGH);
        digitalWrite(B, LOW);
        digitalWrite(C, HIGH);
        digitalWrite(D, HIGH);
        digitalWrite(E, HIGH);
        digitalWrite(F, HIGH);
        digitalWrite(G, HIGH);
        break;

      case 7:
        digitalWrite(A, HIGH);
        digitalWrite(B, HIGH);
        digitalWrite(C, HIGH);
        digitalWrite(D, LOW);
        digitalWrite(E, LOW);
        digitalWrite(F, LOW);
        digitalWrite(G, LOW);
        break;

      case 8:
        digitalWrite(A, HIGH);
        digitalWrite(B, HIGH);
        digitalWrite(C, HIGH);
        digitalWrite(D, HIGH);
        digitalWrite(E, HIGH);
        digitalWrite(F, HIGH);
        digitalWrite(G, HIGH);
        break;

      case 9:
        digitalWrite(A, HIGH);
        digitalWrite(B, HIGH);
        digitalWrite(C, HIGH);
        digitalWrite(D, HIGH);
        digitalWrite(E, LOW);
        digitalWrite(F, HIGH);
        digitalWrite(G, HIGH);
        break;
    }
    ptimeS = ctimeS;
  }
}