#include <EEPROM.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 20, 4);

int mem_status_addr = 10;
int mem_config_addr = 20;
int config_value= -999;
int program_button = 3;

byte mem_init_false = B10100111;
byte mem_init_true = B11100011;

bool is_config_saved = false;


void init_memory() {
  byte curr_mem_status;
  curr_mem_status = EEPROM.read(mem_status_addr);
  if ((curr_mem_status != mem_init_false) and (curr_mem_status != mem_init_true)) {
    EEPROM.write(mem_status_addr, mem_init_false);
  }
  else{
    is_config_saved = (curr_mem_status == mem_init_true);
  }
}

void save_config( byte test_value) {
  config_value = test_value;
  EEPROM.write(mem_config_addr, config_value);
  is_config_saved = true;

  // lcd.setCursor(1, 0);
  // lcd.print('Saved config');
  // lcd.setCursor(2, 0);
  // lcd.print('test_value');
}

void read_config(){
  config_value = EEPROM.read(mem_config_addr);
  // lcd.setCursor(0, 0);
  // lcd.print('Saved config');
  lcd.setCursor(3, 1);
  lcd.print('test_value');
}

void led_on(){
  digitalWrite(LED_BUILTIN, HIGH);
}

void led_off(){
  digitalWrite(LED_BUILTIN, LOW);
}

void blink( int period = 1000){
  led_on();
  delay(500);
  led_off();
  delay(500);
}

void setup() {
  lcd.init();
  lcd.backlight();
  lcd.setCursor(1, 0);
  // ----------------  
  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(3, INPUT);
  init_memory();
  blink();
  // --------------------
  lcd.init();
  lcd.backlight();
  delay(100);

}


void loop() {
  // put your main code here, to run repeatedly:
  // Serial.println(is_config_saved);
  lcd.setCursor( 0, 0);
  lcd.print("Config is saved:");
  lcd.setCursor( 0, 1);
  lcd.print(is_config_saved);

  if (is_config_saved != true){
    blink();    
    if (digitalRead(program_button)){
      save_config(54);
    }
  }
  else {
    led_off();    
  }

}