#include <LiquidCrystal_I2C.h>
#include <Wire.h>

#define UP 2
#define DOWN 3
#define START 4
#define RELAY 5
#define LDR A1
#define NTC A0

LiquidCrystal_I2C lcd(0x27, 16,2);

int time=0;
int ttime=0;

int btime=0;

int tset=0;
int tchange=0;
int tcur=0;

const float BETA = 3950; // should match the Beta Coefficient of the thermistor


bool tup=0;
bool Cup=0;
bool tdown=0;
bool Cdown=0;
bool start=0;

bool sv=false;

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

  pinMode(UP, INPUT);
  pinMode(DOWN, INPUT);
  pinMode(START, INPUT);

  pinMode(13, OUTPUT);
  pinMode(RELAY, OUTPUT);

  lcd.init();
  lcd.clear();
  lcd.backlight();

  lcd.setCursor(3,0);
  lcd.print("MADE  IN");
  lcd.setCursor(3,1);
  lcd.print("TEXNOLAB");
  delay(2000);
  lcd.clear();
}

void loop() {
  // put your main code here, to run repeatedly:
  //Serial.print("UP- ");
  //Serial.print(digitalRead(UP));
  //Serial.print(" DOWN- ");
  //Serial.print(digitalRead(DOWN));
  //Serial.print(" START- ");
  //Serial.println(digitalRead(START));

  Cup=digitalRead(UP);
  Cdown=digitalRead(DOWN);

  if(!Cup && Cdown)
  {    
   if(Cup!=tup)
   {
     tchange++;
     btime=millis();
   } 
   else if(Cup==tup && millis()-btime>2000 && (millis()-btime)%200<100) tchange++;
  } 
  tup=Cup;

  if(!Cdown &&  Cup)
  {
    if(Cdown!=tdown)
   {
     tchange--;
     btime=millis();
   } 
   else if(Cdown==tdown && millis()-btime>2000 && (millis()-btime)%200<100) tchange--;
  } 
  tdown=Cdown;  

  if(!digitalRead(START))
  {
    tset=tchange;
    ttime=millis();
    start=true;
  } 

  if(tset>tcur )
  {
    digitalWrite(13, HIGH);
    digitalWrite(RELAY, HIGH);
    sv=true;
  }
  else
  {
    digitalWrite(13, LOW);
    digitalWrite(RELAY, LOW);
    sv=false;
  }

  //Serial.print("Tcur- ");
  //Serial.print(tcur);
  //Serial.print(" Tset- ");
  //Serial.print(tset);
  //Serial.print(" Tchange- ");
  //Serial.print(tchange);

  int tAnalog=analogRead(NTC);
  tcur = 1 / (log(1 / (1023. / tAnalog - 1)) / BETA + 1.0 / 298.15) - 273.15;

  
  if(start) time=(millis()-ttime)/1000;
  //Serial.print(" Time- ");
  //Serial.print(time);
  //Serial.print(" Time- ");
  //Serial.print(millis());

  //Serial.print(" LDR- ");
  //Serial.println(analogRead(LDR));

  lcd.setCursor(0,0);
  lcd.print("TEM IDT SV TM  I");
  lcd.setCursor(0,1);  
  if(0<=tcur && tcur<10) lcd.print(' ');
  lcd.print(tcur);
  lcd.print(char(223));
  if(tcur>-10) lcd.print(' ');
  lcd.setCursor(4,1);
  if(tset!=tchange)
  {
    if(millis()%300<50) lcd.print("   ");
    else
    {      
      if(0<=tchange && tchange<10) lcd.print(' ');
      lcd.print(tchange);
      lcd.print(char(223));
      if(tchange>-10) lcd.print(' ');
    }     
  } 
  else
  {
    if(0<=tset && tset<10) lcd.print(' ');
    lcd.print(tset);
    lcd.print(char(223));
    if(tset>-10) lcd.print(' ');
  }
  lcd.setCursor(8,1);
  if(sv) lcd.print("AK");
  else lcd.print("PS");

  lcd.setCursor(11,1);
  lcd.print(time);
  if(time<10) lcd.print("  ");
  else if(time<100) lcd.print(" ");

  lcd.setCursor(15,1);
  if(analogRead(LDR)<300) lcd.print('G');
  else lcd.print('Q');
}