#include <LiquidCrystal_I2C.h>

#define PIN_ULTRASONIC_ECHO (2)
#define PIN_ULTRASONIC_TRIGGER (A1)

#define I2C_ADDR    0x27
#define LCD_COLUMNS 16
#define LCD_LINES   2

#define DOWN_BUTTON (11)
#define UP_BUTTON (12)
#define POWER_BUTTON (13)

//Gombok
int DOWN_BUTTON_OLDSTATE ;  //MENU DOWN Button 
int UP_BUTTON_OLDSTATE ;   // MENU UP BUtton
int POWER_BUTTON_OLDSTATE ; // PR POWER BUTTON
int DOWN_BUTTON_STATE ;  //MENU DOWN Button 
int UP_BUTTON_STATE ;   // MENU UP BUtton
int POWER_BUTTON_STATE ; // PR POWER BUTTON
unsigned long(POWER_BUTTON_START) = millis();
unsigned long(UP_BUTTON_START) = millis();
unsigned long(DOWN_BUTTON_START) = millis();

// Mérés
void isr_us(void);
unsigned long us_start;
unsigned long us_end;
bool measurementReady = false;

// LCD Függvényei
LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);
void lcd_clear (void);
void lcd_default (void);
void lcd_time_write(float);

// Tömb deklaráció
const int rows = 14;
const int cols = 2;
int ShutterTimeArray[rows][cols] = {
  {1000, 1},
  {500, 2},
  {300, 3},
  {250, 4},
  {200, 5},
  {125, 8},
  {100, 10},
  {60,  16},
  {30,  33},
  {15,  66},
  {10,  100},
  {5,   200},
  {2,   500},
  {1,   1000}
};

int sor =6;

void setup() {
  
  Serial.begin(115200);
  
  // Init LCD
  lcd.init();
  lcd.backlight();
  lcd_default();

  // Init PR Interupt 
  pinMode(PIN_ULTRASONIC_ECHO, INPUT);
  pinMode(PIN_ULTRASONIC_TRIGGER, OUTPUT);
  attachInterrupt(digitalPinToInterrupt(PIN_ULTRASONIC_ECHO),isr_us, CHANGE);

  // Init BUTTONS 
  pinMode(DOWN_BUTTON, INPUT_PULLUP);
  pinMode(UP_BUTTON, INPUT_PULLUP);
  pinMode(POWER_BUTTON, INPUT_PULLUP);
  DOWN_BUTTON_OLDSTATE = digitalRead(DOWN_BUTTON);  //MENU DOWN Button 
  UP_BUTTON_OLDSTATE = digitalRead(UP_BUTTON);    // MENU UP BUtton
  POWER_BUTTON_OLDSTATE = digitalRead(POWER_BUTTON);  // PR POWER BUTTON
}

void loop() {
  
  // Ha a mérés kész
  if (measurementReady){
    noInterrupts();
    measurementReady = false;
    unsigned long timeDelta =  us_end - us_start;
    interrupts();
    lcd_time_write(timeDelta);
    //Serial.println(timeDelta);
    //Serial.print(millio);
    //Serial.print(" sec 1/");
    //Serial.println(time);

  }
  // POWER BUTTON RED
  POWER_BUTTON_STATE = digitalRead(POWER_BUTTON); 
  if (POWER_BUTTON_STATE != POWER_BUTTON_OLDSTATE and millis() >= POWER_BUTTON_START + 5)  {
    POWER_BUTTON_OLDSTATE = POWER_BUTTON_STATE;
    if (POWER_BUTTON_STATE == HIGH) {
      // RELEASED
      POWER_BUTTON_START = millis();             
    }
    if (POWER_BUTTON_STATE == LOW) {
      // PRESSED
      POWER_BUTTON_START = millis();
      int triggerState = digitalRead(PIN_ULTRASONIC_TRIGGER);
      digitalWrite(PIN_ULTRASONIC_TRIGGER, !triggerState);
    }
  }
  // UP BUTTON BLUE
  UP_BUTTON_STATE = digitalRead(UP_BUTTON); 
  if (UP_BUTTON_STATE != UP_BUTTON_OLDSTATE and millis() >= UP_BUTTON_START + 5)  {
    UP_BUTTON_OLDSTATE = UP_BUTTON_STATE;
    if (UP_BUTTON_STATE == HIGH) {
      // RELEASED
      UP_BUTTON_START = millis();             
    }
    if (UP_BUTTON_STATE == LOW) {
      // PRESSED
      if (sor > 0) {
        sor-=1;}
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("1/");
      lcd.print(ShutterTimeArray[sor][0]);
      UP_BUTTON_START = millis();
    }
  } 
  // DOWN BUTTON YELLOW
  DOWN_BUTTON_STATE = digitalRead(DOWN_BUTTON); 
  if (DOWN_BUTTON_STATE != DOWN_BUTTON_OLDSTATE and millis() >= DOWN_BUTTON_START + 5)  {
    DOWN_BUTTON_OLDSTATE = DOWN_BUTTON_STATE;
    if (DOWN_BUTTON_STATE == HIGH) {
      // RELEASED
      DOWN_BUTTON_START = millis();             
    }
    if (DOWN_BUTTON_STATE == LOW) {
      // PRESSED
            if (sor < rows-1 ) {
        sor+=1;}
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("1/");
      lcd.print(ShutterTimeArray[sor][0]);
      UP_BUTTON_START = millis();
      DOWN_BUTTON_START = millis();
    }
  }
}  //loop END

void isr_us(void){
  if(digitalRead(PIN_ULTRASONIC_ECHO) == LOW){
    us_start = micros();
  }
  else{
    us_end = micros();
    measurementReady = true;
  }
}

void lcd_clear (void){
  lcd.setCursor(0, 0);
  lcd.print("                    ");
  lcd.setCursor(0, 1);
  lcd.print("                    ");
}

void lcd_default (void) {
  lcd.setCursor(0, 0);
  lcd.print("SHUTTER SPEED ");
  lcd.setCursor(5, 1);
  lcd.print("TESTER 2024");
}

void lcd_time_write(float timeDelta){
    int millio = (timeDelta / 1000000 );
    timeDelta = timeDelta - (millio * 1000000) ;
    float time = 1000 / float (timeDelta /1000);
    lcd.setCursor(0, 1);
    lcd.print("                ");
    lcd.setCursor(0, 1);
    lcd.print("Time: ");
    lcd.print(millio);
    lcd.print("+1/");
    lcd.print(time);

}