#include <WiFi.h>
#include <NTPClient.h>
#include <WiFiUdp.h>

const char* ssid = "Your WiFi SSID";
const char* password = "Your WiFi Password";

const int notify_hour = 20;
const int notify_minute = 0;

const int local_time_offset = 2 * 3600;

const int led = 1;

bool flashing = false;
bool skip = false;

WiFiUDP ntpUDP;
NTPClient timeClient(ntpUDP);

bool check_time() {
   while(!timeClient.update()) {
    timeClient.forceUpdate();
  }

  int hours = timeClient.getHours();
  int minutes = timeClient.getMinutes();

  if (skip && hours < notify_hour) skip = false;

  if (!skip && (hours > notify_hour || (hours == notify_hour && minutes >= notify_minute))) {
    return true;
  }
  
  return false;
}

void setup() {
  // Serial.begin(115200);
  pinMode(led, OUTPUT);
  digitalWrite(led, HIGH);

  // Serial.print("Connecting to ");
  // Serial.println(ssid);
  WiFi.begin(ssid, password);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    // Serial.print(".");
  }

  /* Serial.println("");
  Serial.println("WiFi connected.");
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP()); */

  timeClient.begin();
  timeClient.setTimeOffset(local_time_offset);

  if (check_time()) skip = true;
}

void loop() {
  if (!flashing) {
    flashing = check_time();
    if (!flashing) delay(30000);
    return;
  }

  if (!skip) {
    digitalWrite(led, LOW);
    delay(500);
    digitalWrite(led, HIGH);
    delay(500);
  }
}