#include <Wire.h> 
#include <LiquidCrystal_I2C.h>
#include <EEPROM.h>
#include <OneWire.h>
#include <DallasTemperature.h>

#define BUTTON_UP_PIN 2
#define BUTTON_DOWN_PIN 3
#define BUTTON_LEFT_PIN 4
#define BUTTON_RIGHT_PIN 5
#define BUTTON_SELECT_PIN 6

#define BUZZER_PIN 8
#define BUZZER_LOCK_BUTTON 7
#define TEMP_CHANGE_THRESHOLD 0.5
#define TEMP_READ_INTERVAL 5000
#define SENSOR_CHECK_INTERVAL 30000
#define NUM_SENSORS 2
#define NUM_READINGS 5

LiquidCrystal_I2C lcd(0x27, 20, 4);
OneWire oneWire(2);
DallasTemperature sensors(&oneWire);

int screen = 1;
int settingIndex = 0;
int settings[3] = {50, 100, 200};

float temperatures[NUM_SENSORS][NUM_READINGS];
unsigned int currentReading = 0;
float averagedTemperature = 0.0;
bool buzzerEnabled = true;
bool buzzerLocked = false;
bool sensorError[NUM_SENSORS] = {false};

unsigned long lastTempReadTime = 0;
unsigned long lastSensorCheckTime = 0;
unsigned long lastBuzzerLockTime = 0;
unsigned long buzzerAlarmStartTime = 0;
unsigned long debounceDelay = 50;
bool buttonState = HIGH;

void setup() {
  Serial.begin(9600);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(BUZZER_LOCK_BUTTON, INPUT_PULLUP);
  lcd.init();
  lcd.backlight();
  sensors.begin();
  
  // First code setup
  pinMode(BUTTON_UP_PIN, INPUT_PULLUP);
  pinMode(BUTTON_DOWN_PIN, INPUT_PULLUP);
  pinMode(BUTTON_LEFT_PIN, INPUT_PULLUP);
  pinMode(BUTTON_RIGHT_PIN, INPUT_PULLUP);
  pinMode(BUTTON_SELECT_PIN, INPUT_PULLUP);
  displayMainScreen();
}

void loop() {
  if(screen == 1) {
    handleMainScreen();
  } else if(screen == 2) {
    handleSettingsScreen();
  } else {
    if (!sensorError[0] || !sensorError[1]) {
      if (millis() - lastTempReadTime >= TEMP_READ_INTERVAL) {
        readTemperatures();
        updateDisplay();
        lastTempReadTime = millis();
      }
      if (millis() - lastSensorCheckTime >= SENSOR_CHECK_INTERVAL) {
        checkSensorStatus();
        lastSensorCheckTime = millis();
      }
    } else {
      if (!buzzerLocked) {
        buzzerAlarmStartTime = millis();
        buzzerAlarm();
      } else {
        if (millis() - buzzerAlarmStartTime >= 5000) {
          buzzerLocked = false;
        }
      }
      for (int i = 0; i < NUM_SENSORS; ++i) {
        sensorError[i] = false;
      }
    }
    checkBuzzerLockButton();
  }
}

void displayMainScreen() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Main Screen");
}

void handleMainScreen() {
  if(digitalRead(BUTTON_SELECT_PIN) == LOW) {
    screen = 2;
    displaySettingsScreen();
    delay(200);
  }
}

void displaySettingsScreen() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Settings");

  for(int i = 0; i < 3; i++) {
    lcd.setCursor(0, i + 1);
    if(i == settingIndex) {
      lcd.print(">");
    } else {
      lcd.print(" ");
    }
    lcd.print("Setting ");
    lcd.print(i + 1);
    lcd.print(": ");
    lcd.print(settings[i]);
  }
}

void handleSettingsScreen() {
  if(digitalRead(BUTTON_SELECT_PIN) == LOW) {
    saveSetting(settingIndex);
    screen = 1;
    displayMainScreen();
    delay(200);
  } else if(digitalRead(BUTTON_UP_PIN) == LOW) {
    changeSetting(1);
    displaySettingsScreen();
    delay(200);
  } else if(digitalRead(BUTTON_DOWN_PIN) == LOW) {
    changeSetting(-1);
    displaySettingsScreen();
    delay(200);
  } else if(digitalRead(BUTTON_LEFT_PIN) == LOW) {
    settingIndex = (settingIndex + 2) % 3;
    displaySettingsScreen();
    delay(200);
  } else if(digitalRead(BUTTON_RIGHT_PIN) == LOW) {
    settingIndex = (settingIndex + 1) % 3;
    displaySettingsScreen();
    delay(200);
  }
}

void changeSetting(int change) {
  settings[settingIndex] += change;
  if(settings[settingIndex] < 0) {
    settings[settingIndex] = 0;
  }
}

void saveSetting(int index) {
  EEPROM.put(index * sizeof(int), settings[index]);
}

void readTemperatures() {
  sensors.requestTemperatures();
  for (int i = 0; i < NUM_SENSORS; ++i) {
    float temp = sensors.getTempCByIndex(i);
    if (temp == DEVICE_DISCONNECTED_C) {
      sensorError[i] = true;
      temperatures[i][currentReading] = -127.0;
    } else {
      temperatures[i][currentReading] = round(temp * 10) / 10.0;
    }
  }
  currentReading = (currentReading + 1) % NUM_READINGS;
  averagedTemperature = calculateAverageTemperature();
}

void updateDisplay() {
  lcd.clear();
  lcd.setCursor(0, 0);
  if (!sensorError[0]) {
    lcd.print("Temp1: ");
    lcd.print(temperatures[0][currentReading], 1);
    lcd.print(" C");
  } else {
    lcd.print("Blad czujnika 1");
  }

  lcd.setCursor(0, 1);
  if (!sensorError[1]) {
    lcd.print("Temp2: ");
    lcd.print(temperatures[1][currentReading], 1);
    lcd.print(" C");
  } else {
    lcd.print("Blad czujnika 2");
  }
}

float calculateAverageTemperature() {
  float total[NUM_SENSORS] = {0.0};
  for (int i = 0; i < NUM_SENSORS; ++i) {
    for (int j = 0; j < NUM_READINGS; ++j) {
      total[i] += temperatures[i][j];
    }
  }
  return total[0] / NUM_READINGS;
}

void buzzerAlarm() {
  if (buzzerEnabled) {
    for (int i = 0; i < 3; ++i) {
      tone(BUZZER_PIN, 1000);
      delay(200);
      noTone(BUZZER_PIN);
      delay(200);
    }
  }
}

void checkSensorStatus() {
  for (int i = 0; i < NUM_SENSORS; ++i) {
    float temp = sensors.getTempCByIndex(i);
    if (temp == DEVICE_DISCONNECTED_C) {
      sensorError[i] = true;
    }
  }
}

void checkBuzzerLockButton() {
  unsigned long currentTime = millis();
  if (currentTime - lastBuzzerLockTime >= debounceDelay) {
    bool newButtonState = digitalRead(BUZZER_LOCK_BUTTON);
    if (newButtonState != buttonState) {
      if (newButtonState == LOW) {
        buzzerLocked = !buzzerLocked;
      }
      buttonState = newButtonState;
    }
    lastBuzzerLockTime = currentTime;
  }
}