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

RTC_DS3231 rtc;
LiquidCrystal_I2C lcd(0x27, 16, 2);

int led = 7;
int ldr = A0;
int ldr_status = 0;

void setup() {
  rtc.begin();
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  pinMode(led, OUTPUT);
  digitalWrite(led, LOW);
  pinMode(ldr, INPUT);
  if (rtc.lostPower()) {
    Serial.println("RTC lost power, let's set the time!");
    // When time needs to be set on a new device, or after a power loss, the
    // following line sets the RTC to the date & time this sketch was compiled
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
    // This line sets the RTC with an explicit date & time, for example to set
    // January 21, 2014 at 3am you would call:
    // rtc.adjust(DateTime(2014, 1, 21, 3, 0, 0));
  }

  // When time needs to be re-set on a previously configured device, the
  // following line sets the RTC to the date & time this sketch was compiled
  // rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  // This line sets the RTC with an explicit date & time, for example to set
  // January 21, 2014 at 3am you would call:
  // rtc.adjust(DateTime(2014, 1, 21, 3, 0, 0));
}

void loop() {
  ldr_status = analogRead(A0);
  DateTime now = rtc.now();
  lcd.setCursor(0, 0);
  lcd.print(now.year());
  lcd.print("/");
  lcd.print(now.month());
  lcd.print("/");
  lcd.print(now.day());
  lcd.print(" ");
  lcd.print(now.hour());
  lcd.print(":");
  lcd.print(now.minute());
  lcd.print(":");
  lcd.print(now.second());
  lcd.print("    ");
  lcd.setCursor(0, 1);
  lcd.print(ldr_status);
  lcd.print("    ");
  lcd.setCursor(4, 1);
  lcd.print(" LED:");

  if (ldr_status < 700) {
    lcd.setCursor(9, 1);
    lcd.print("ON  ");
    digitalWrite(led, HIGH);
  }
  else {
    // 18 - 19 - 20 - 21 - 22 - 23 - 0 - 1 - 2 - 3 - 4 - 5 - 6
    if (now.hour() == 18 || now.hour() == 19 || now.hour() == 20 || now.hour() == 21 || now.hour() == 22 || now.hour() == 23 || now.hour() == 0 || now.hour() == 1 || now.hour() == 2 || now.hour() == 3 || now.hour() == 4 || now.hour() == 5 ) {
        lcd.setCursor(9, 1);
        lcd.print("ON  ");
        digitalWrite(led, HIGH);

    }
    else {
      lcd.setCursor(9, 1);
      lcd.print("OFF");
      digitalWrite(led, LOW);
    }
  }
  delay(1000);
}