#include <Arduino.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

#define LED1_PIN 12
#define LED2_PIN 13

#define LCD_ADDRESS 0x27
#define LCD_COLUMNS 16
#define LCD_ROWS 2

LiquidCrystal_I2C lcd(LCD_ADDRESS, LCD_COLUMNS, LCD_ROWS);

struct LED {
  int period;
  int duty_cycle;
  bool working;
};

LED led1 = {0, 0, false};
LED led2 = {0, 0, false};

unsigned long previousMillis = 0;

void setup() {
  Serial.begin(9600);
  pinMode(LED1_PIN, OUTPUT);
  pinMode(LED2_PIN, OUTPUT);

  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("00:00");
}

void loop() {
  unsigned long currentMillis = millis();
  unsigned long elapsedMillis = currentMillis - previousMillis;

  if (elapsedMillis >= 1000) {
    previousMillis = currentMillis;

    // Update and display current time
    static unsigned long startTime = millis();
    unsigned long elapsedTime = currentMillis - startTime;
    unsigned long minutes = elapsedTime / 60000;
    unsigned long seconds = (elapsedTime / 1000) % 60;
    lcd.setCursor(0, 0);
    lcd.print(String(minutes, DEC));
    lcd.print(":");
    if (seconds < 10) {
      lcd.print("0");
    }
    lcd.print(String(seconds, DEC));

    // Display LED settings
    lcd.setCursor(0, 1);
    if (led1.working) {
      lcd.print("1:" + String(led1.period) + ":" + String(led1.duty_cycle) + " ");
    } else {
      lcd.print("1:OFF ");
    }
    if (led2.working) {
      lcd.print("2:" + String(led2.period) + ":" + String(led2.duty_cycle));
    } else {
      lcd.print("2:OFF ");
    }
  }

  // Read serial input
  if (Serial.available() > 0) {
    String input = Serial.readStringUntil('\n');
    int led_number = input.substring(0, input.indexOf(":")).toInt();
    int period = input.substring(input.indexOf(":") + 1, input.lastIndexOf(":")).toInt();
    int duty_cycle = input.substring(input.lastIndexOf(":") + 1).toInt();

    // Update LED settings
    if (led_number == 1) {
      led1.period = period;
      led1.duty_cycle = duty_cycle;
      led1.working = (period != 0);
    } else if (led_number == 2) {
      led2.period = period;
      led2.duty_cycle = duty_cycle;
      led2.working = (period != 0);
    }

    // Output message to serial port
    Serial.println("LED" + String(led_number) + " updated: period=" + String(period) + ", duty cycle=" + String(duty_cycle));
  }

  // Update LED states
  updateLED(LED1_PIN, led1);
  updateLED(LED2_PIN, led2);
}

void updateLED(int pin, LED &led) {
  if (led.working) {
    int high_duration = (led.period * led.duty_cycle) / 100;
    int low_duration = led.period - high_duration;

    int state = (millis() % led.period) < high_duration ? HIGH : LOW;
    digitalWrite(pin, state);
  } else {
    digitalWrite(pin, LOW);
  }
}