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

const int relayPin = 7; // Pino do relé
const int sensorPin = A0; // Pino do sensor ACS712

LiquidCrystal_I2C lcd(0x27, 16, 2); // Substitua 0x27 pelo endereço I2C correto

const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};
byte rowPins[ROWS] = {9, 8, 7, 6};
byte colPins[COLS] = {5, 4, 3, 2};

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

float weight = 0.0;
int mils = 0;
float current = 0.0;
float timeToRun = 0.0;
unsigned long endTime = 0;
bool running = false;
bool inputWeight = true;
String weightStr = "000,0";
String milsStr = "";
unsigned long lastCalculationTime = 0;

void setup() {
  pinMode(relayPin, OUTPUT);
  digitalWrite(relayPin, LOW);
  lcd.begin(16, 2); // Inicializa o LCD com 16 colunas e 2 linhas
  lcd.backlight();
  displayInitialScreen();
}

void loop() {
  if (!running) {
    handleInput();
  } else {
    unsigned long currentTime = millis();
    if (currentTime - lastCalculationTime >= 1000) {
      measureCurrent();
      calculateTime();
      lastCalculationTime = currentTime;
    }
    controlRelay();
    displayRemainingTime();
  }
}

void handleInput() {
  char key = keypad.getKey();
  
  if (key) {
    if (inputWeight) {
      if (key == '#') {
        inputWeight = false;
        lcd.setCursor(0, 1);
        lcd.print("Mls: ");
        lcd.setCursor(6, 1);
        lcd.print(milsStr);
      } else if (key == 'B') {
        cancelOperation();
      } else if (key == 'D') {
        weightStr = "000,0";
        lcd.setCursor(6, 0);
        lcd.print(weightStr);
      } else {
        weightStr = updateWeightString(weightStr, key);
        lcd.setCursor(6, 0);
        lcd.print(weightStr);
      }
    } else {
      if (key == 'A') {
        mils = milsStr.toInt();
        startOperation();
      } else if (key == 'B') {
        cancelOperation();
      } else if (key == 'D') {
        milsStr = "";
        lcd.setCursor(6, 1);
        lcd.print("    ");
      } else if (key == '#') {
        inputWeight = true;
        lcd.setCursor(6, 0);
        lcd.print(weightStr);
      } else {
        milsStr += key;
        lcd.setCursor(6, 1);
        lcd.print(milsStr);
      }
    }
  }
}

String updateWeightString(String current, char newChar) {
  current.remove(0, 1); // Remove o primeiro caractere
  int commaIndex = current.indexOf(',');
  current.remove(commaIndex, 1); // Remove a vírgula
  current += newChar; // Adiciona o novo caractere no final
  current = current.substring(0, commaIndex) + ',' + current.substring(commaIndex); // Reposiciona a vírgula
  return current;
}

void measureCurrent() {
  int sensorValue = analogRead(sensorPin);
  current = ((float)sensorValue - 512) * (5.0 / 1023.0);
}

void calculateTime() {
  if (current != 0) {
    timeToRun = (weight * mils) / (68.0 * current);
    endTime = millis() + (unsigned long)(timeToRun * 1000); // Tempo final em milissegundos
  }
}

void controlRelay() {
  if (millis() >= endTime) {
    digitalWrite(relayPin, LOW);
    running = false;
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Operacao");
    lcd.setCursor(0, 1);
    lcd.print("Concluida");
    delay(3000); // Aguardar 3 segundos antes de reiniciar
    displayInitialScreen(); // Exibir a tela inicial novamente
  } else {
    digitalWrite(relayPin, HIGH);
  }
}

void displayRemainingTime() {
  unsigned long remainingTime = (endTime - millis()) / 1000;
  int minutes = remainingTime / 60;
  int seconds = remainingTime % 60;
  lcd.setCursor(0, 0);
  lcd.print("Tempo restante: ");
  lcd.setCursor(0, 1);
  lcd.print(minutes);
  lcd.print(":");
  if (seconds < 10) {
    lcd.print("0");
  }
  lcd.print(seconds);
  lcd.print("    "); // Espaços para garantir que não há resíduos de caracteres anteriores
}

void startOperation() {
  weight = weightStr.toFloat();
  mils = milsStr.toInt();
  running = true;
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Em Execucao");
  measureCurrent(); // Medir a corrente imediatamente antes de iniciar a operação
  calculateTime(); // Calcular o tempo de operação com base na corrente medida
}

void cancelOperation() {
  running = false;
  digitalWrite(relayPin, LOW);
  weight = 0.0;
  mils = 0;
  weightStr = "000,0";
  milsStr = "";
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Operacao");
  lcd.setCursor(0, 1);
  lcd.print("Cancelada");
  delay(3000); // Aguardar 3 segundos antes de reiniciar
  displayInitialScreen(); // Exibir a tela inicial novamente
}

void displayInitialScreen() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Peso: 000,0");
  lcd.setCursor(0, 1);
  lcd.print("Mls: ");
  inputWeight = true;
}