Arduino ON and OFF timer

This an expanded version of my other ON OFF Arduino programs, here we have additional options to set time to both ON and OFF the device. Here the device ON after the time set to “ontime” and OFF after the “offtime”.

Here the switch connected to pin3 can be used to change on time and pin4 to change the off time. The pin2 is the same as above to turn ON the device.

#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);
uint8_t clock[8] = {0x0, 0xe, 0x15, 0x17, 0x11, 0xe, 0x0};
const int switch_on = 2, input_on_time = 3, input_off_time = 4, output = 9;
int timer_start = 0, ontime = 0, offtime = 0;
String device_status = "OFF";
void setup() {
  pinMode(input_on_time, INPUT);
  pinMode(input_off_time, INPUT);
  pinMode(output, OUTPUT);
  lcd.init();
  lcd.backlight();
  lcd.createChar(2, clock);
  lcd.setCursor(8, 1);
  lcd.write(2);
  lcd.print((String)" OFF" + offtime + " ");
  lcd.setCursor(0, 1);
  lcd.write(2);
  lcd.print((String)" ON" + ontime + " ");
  lcd.setCursor(6, 0);
  lcd.print("OFF       ");
}

void loop() {
  int x = ((millis() / 1000) - timer_start)/60;
  if (x <= ontime && device_status == "TO_ON") {
    int m = ((ontime*60) + timer_start - (millis() / 1000))/60;
    int s = ((ontime*60) + timer_start - (millis() / 1000))%60;
    lcd.setCursor(10, 0);
    lcd.print((String)" " + m + ":" + s + " ");
  } else if (x - ontime <= offtime && device_status == "TO_OFF") {
    int m = ((offtime*60) + timer_start + (ontime*60) - (millis() / 1000))/60;
    int s = ((offtime*60) + timer_start + (ontime*60) - (millis() / 1000))%60;
    lcd.setCursor(10, 0);
    lcd.print((String)" " + m + ":" + s + " ");
  }
  if (digitalRead(switch_on) == HIGH) {
    timer_start = millis() / 1000;
    device_status = "TO_ON";
  }
  else if (x - ontime >= offtime  && device_status == "TO_OFF") {
    digitalWrite(output, LOW);
    lcd.setCursor(6, 0);
    lcd.print("OFF       ");
    device_status = "OFF";
  } else if (x >= ontime && device_status == "TO_ON") {
    digitalWrite(output, HIGH);
    lcd.setCursor(6, 0);
    lcd.print("ON        ");
    device_status = "TO_OFF";
  }
  while (digitalRead(input_on_time) == HIGH) {
    if (ontime <= 24) {
      ontime += 1;
    } else {
      ontime = 0;
    }
    lcd.setCursor(0, 1);
    lcd.write(2);
    lcd.print((String)" ON" + ontime + " ");
    delay(500);
  }
  while (digitalRead(input_off_time) == HIGH) {
    if (offtime <= 24) {
      offtime += 1;
    } else {
      offtime = 0;
    }
    lcd.setCursor(8, 1);
    lcd.write(2);
    lcd.print((String)" OFF" + offtime + " ");
    delay(500);
  }
}