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

LiquidCrystal_I2C lcd(0x27, 16, 2);

OneWire oneWireMain(4);
OneWire oneWireFreezer(5);
DallasTemperature sensorMain(&oneWireMain);
DallasTemperature sensorFreezer(&oneWireFreezer);

const int btnModeMainPin = 13; 
const int btnModeFreezPin = 27;
const int btnIceMainPin = 18;
const int btnIceFreezPin = 19;
const int pinBuzzer = 23;

// Змінні стану
int stateMain = 0;   // 0 = -30C, 1 = 0C, 2 = +10C
int stateFreez = 0;  // 0 = -50C, 1 = -70C
bool iceMainActive = false;
bool iceFreezActive = false;

float targetMain = -30.0;
float targetFreez = -50.0;

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

  Wire.begin(21, 22);
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("System Loading..");

  sensorMain.begin();
  sensorFreezer.begin();

  pinMode(btnModeMainPin, INPUT_PULLUP);
  pinMode(btnModeFreezPin, INPUT_PULLUP);
  pinMode(btnIceMainPin, INPUT_PULLUP);
  pinMode(btnIceFreezPin, INPUT_PULLUP);
  pinMode(pinBuzzer, OUTPUT);

  delay(1000);
  lcd.clear();
}

void loop() {
  // --- 1. КНОПКИ РЕЖИМІВ ---
  if (digitalRead(btnModeMainPin) == LOW) {
    while (digitalRead(btnModeMainPin) == LOW); // антидребезг
    stateMain++;
    if (stateMain > 2) stateMain = 0;

    if (stateMain == 0) targetMain = -30.0;
    else if (stateMain == 1) targetMain = 0.0;
    else targetMain = 10.0;

    tone(pinBuzzer, 2000, 50);
  }

  if (digitalRead(btnModeFreezPin) == LOW) {
    while (digitalRead(btnModeFreezPin) == LOW);
    stateFreez++;
    if (stateFreez > 1) stateFreez = 0;

    if (stateFreez == 0) targetFreez = -50.0;
    else targetFreez = -70.0;

    tone(pinBuzzer, 2000, 50);
  }

  // --- 2. КНОПКИ ЛЬОДУ ---
  if (digitalRead(btnIceMainPin) == LOW) {
    while (digitalRead(btnIceMainPin) == LOW);
    iceMainActive = !iceMainActive;
    tone(pinBuzzer, 500, 100);
  }

  if (digitalRead(btnIceFreezPin) == LOW) {
    while (digitalRead(btnIceFreezPin) == LOW);
    iceFreezActive = !iceFreezActive;
    tone(pinBuzzer, 500, 100);
  }

  // --- 3. ОТРИМАННЯ ТЕМПЕРАТУРИ ---
  sensorMain.requestTemperatures();
  sensorFreezer.requestTemperatures();
  float currMain = sensorMain.getTempCByIndex(0);
  float currFreez = sensorFreezer.getTempCByIndex(0);

  // --- 4. ПЕРЕВІРКА ПОХИБКИ ---
  bool alarmTempMain = false;
  bool alarmTempFreez = false;

  float limitMain = (targetMain == 0) ? 1.0 : abs(targetMain * 0.05);
  float limitFreez = abs(targetFreez * 0.05);

  if (abs(currMain - targetMain) > limitMain) alarmTempMain = true;
  if (abs(currFreez - targetFreez) > limitFreez) alarmTempFreez = true;

  // --- 5. ВІДОБРАЖЕННЯ ТА ТРИВОГА ---

  // Пріоритет 1: ЛІД
  if (iceMainActive || iceFreezActive) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("!!! WARNING !!!");
    lcd.setCursor(0, 1);

    if (iceMainActive && iceFreezActive) lcd.print("ICE: BOTH CAMS!");
    else if (iceMainActive) lcd.print("ICE: MAIN CAM!");
    else lcd.print("ICE: FREEZER!");

    tone(pinBuzzer, 1000);
    delay(300);
    noTone(pinBuzzer);
    delay(100);
    return;
  }

  // Пріоритет 2: ТЕМПЕРАТУРА
  if (alarmTempMain || alarmTempFreez) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("!!! TEMP ALARM !!!");

    lcd.setCursor(0, 1);
    if (alarmTempMain && alarmTempFreez) {
      lcd.print("MAIN & FREEZ ERR");
    }
    else if (alarmTempMain) {
      lcd.print("MAIN: ");
      lcd.print(currMain, 1);
    }
    else {
      lcd.print("FREEZ: ");
      lcd.print(currFreez, 1);
    }

    tone(pinBuzzer, 400);
    delay(500);
    noTone(pinBuzzer);
    return;
  }

  // Пріоритет 3: НОРМАЛЬНА РОБОТА
  noTone(pinBuzzer);
  lcd.setCursor(0, 0);
  lcd.print("M:");
  lcd.print(currMain, 1);
  lcd.print(" /Set:");
  lcd.print((int)targetMain);
  lcd.print(" ");

  lcd.setCursor(0, 1);
  lcd.print("F:");
  lcd.print(currFreez, 1);
  lcd.print(" /Set:");
  lcd.print((int)targetFreez);
  lcd.print(" ");

  delay(200);
}