#include <WiFi.h>
#include <NTPClient.h>
#include <TimeLib.h>
#include <TaskScheduler.h>

const char *ssidOptions[] = {"Wokwi-GUEST", "Meteor.flash", "meteor", "Pixel"};
const char *passwordOptions[] = {"", "y0internet", "88888888", "88888888"};
const int numNetworks = sizeof(ssidOptions) / sizeof(ssidOptions[0]);

const int digitPins[4] = {4, 19, 21, 22};
const int clockPin = 18;
const int latchPin = 5;
const int dataPin = 23;
const int secondIndicatorPin = 15;
const int alarmPin = 17;

const byte digit[10] = {
    B00111111, // 0
    B00000110, // 1
    B01011011, // 2
    B01001111, // 3
    B01100110, // 4
    B01101101, // 5
    B01111101, // 6
    B00000111, // 7
    B01111111, // 8
    B01101111  // 9
};

int digitBuffer[4] = {0};
int digitScan = 0;

WiFiUDP ntpUDP;
NTPClient timeClient(ntpUDP);

bool alarmEnabled = false;
unsigned long alarmStartTime = 0;

Scheduler scheduler;

void connectToWiFi() {
  Serial.println("Connecting to WiFi...");

  for (int i = 0; i < numNetworks; ++i) {
    WiFi.begin(ssidOptions[i], passwordOptions[i]);
    int attempts = 0;

    while (WiFi.status() != WL_CONNECTED && attempts < 20) {
      delay(1000);
      Serial.println("Connecting...");
      attempts++;
    }

    if (WiFi.status() == WL_CONNECTED) {
      Serial.println("Connected to WiFi");
      return;
    } else {
      Serial.println("Connection failed. Retrying...");
      WiFi.disconnect();
      delay(1000);
    }
  }

  Serial.println("Failed to connect to any WiFi network");
}

void updateDisp() {
  for (byte j = 0; j < 4; j++)
    digitalWrite(digitPins[j], LOW);

  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, MSBFIRST, B11111111);
  digitalWrite(latchPin, HIGH);

  delayMicroseconds(5);
  digitalWrite(digitPins[digitScan], HIGH);

  digitalWrite(latchPin, LOW);
  if (digitScan == 0)
    shiftOut(dataPin, clockPin, MSBFIRST, ~(digit[digitBuffer[digitScan]] | B10000000));
  else
    shiftOut(dataPin, clockPin, MSBFIRST, ~digit[digitBuffer[digitScan]]);

  digitalWrite(latchPin, HIGH);
  digitScan++;
  if (digitScan > 3) digitScan = 0;
}

void handleAlarm() {
  unsigned long currentTime = millis();
  unsigned long elapsedTime = currentTime - alarmStartTime;

  if (elapsedTime < 120000) { // 2 minutes
    digitalWrite(alarmPin, HIGH);
  } else if (elapsedTime < 240000) { // 2 minutes break
    digitalWrite(alarmPin, LOW);
  } else {
    alarmStartTime = currentTime;
  }
}

void setAlarmTime() {
  Serial.println("Enter alarm time (HH:MM): ");
  while (Serial.available() < 5)
    ;

  String input = Serial.readStringUntil('\n');
  int hours = input.substring(0, 2).toInt();
  int minutes = input.substring(3, 5).toInt();

  alarmStartTime = hours * 3600000 + minutes * 60000;
  Serial.println("Alarm set for " + input);
}

void updateTime() {
  timeClient.update();

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

  digitBuffer[3] = hours / 10;
  digitBuffer[2] = hours % 10;
  digitBuffer[1] = minutes / 10;
  digitBuffer[0] = minutes % 10;

  updateDisp();
  digitalWrite(secondIndicatorPin, seconds % 2 == 0 ? HIGH : LOW);
}

void setup() {
  Serial.begin(115200);
  delay(5);

  connectToWiFi();

  timeClient.begin();
  timeClient.setTimeOffset(2 * 3600);

  for (int i = 0; i < 4; i++) {
    pinMode(digitPins[i], OUTPUT);
  }

  pinMode(latchPin, OUTPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(dataPin, OUTPUT);
  pinMode(secondIndicatorPin, OUTPUT);
  pinMode(alarmPin, OUTPUT);

  digitalWrite(alarmPin, LOW);

  scheduler.init();

  Task updateTask(1000, TASK_FOREVER, &updateTime);
  Task alarmTask(1000, TASK_FOREVER, &handleAlarm);
  Task dispTask(5, TASK_FOREVER, &updateDisp);
  Task setAlarmTask(100, TASK_FOREVER, &setAlarmTime);

  scheduler.addTask(updateTask);
  scheduler.addTask(alarmTask);
  scheduler.addTask(dispTask);
  scheduler.addTask(setAlarmTask);

  updateTask.enable();
  alarmTask.enable();
  dispTask.enable();
  setAlarmTask.enable();
}

void loop() {
  scheduler.execute();
}