#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <Keypad.h>
//Keypad
const byte ROW = 4;
const byte COL = 4;
char keys[ROW][COL] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};
const int PASS_LENGTH = 5;
const char PASSWORD[] = { '1', '2', '3' ,'A', 'B' };
const int MAX_ATTEMPT = 3;
byte rowP[ROW] = {9, 8, 7, 6};
byte colP[COL] = {5, 4, 3, 2};
Keypad key = Keypad(makeKeymap(keys), rowP, colP, ROW, COL);
const int PIN_BUZZER = 10;
//LCD
LiquidCrystal_I2C lcd(0x27, 16, 2);
byte sensorInt = 0;
byte flowsensor = 11;
float konstanta = 5.5;
float debit;
float liter;
float volume;
unsigned long oldTime;
unsigned int flowmlt;
volatile byte pulseCount;
const int relay = 12;
int i = 0, q = 0, j = 0, p = 0, pass;
long beli, harga, harga5 = 0;
char stringAngka[10];
char str[10];
char harga2[10];
long double harga3;
long harga4;
void setup() 
{
  Serial.begin(9600);
  lcd.init();
  lcd.backlight();
  pinMode(flowsensor, INPUT);
  digitalWrite(flowsensor, HIGH);
  pulseCount = 0;
  debit = 0.0;
  flowmlt = 0;
  volume = 0.0;
  oldTime = 0;
  attachInterrupt(sensorInt, pulseCounter, FALLING);
  pinMode(relay, OUTPUT);
  lcd.setCursor(0, 0);
  lcd.print("POM MINI KINGS");
  lcd.setCursor(0, 1);
  lcd.print("TAMAN SEMANAN INDAH");
  lcd.setCursor(0, 2);
  lcd.print("HARGA : Rp.");
  lcd.print(harga);
  lcd.print(" /L");
}
void loop() {
  digitalWrite(relay, HIGH);
    char btn = key.getKey();
  if (btn) {
    String cstring = String(str);
    str[q++] = btn;
    if (btn == 'A') {
      lcd.clear();
      beli = beli + 10000;
      lcd.setCursor(0, 0);
      lcd.print("BELI BBM : ");
      lcd.setCursor(0, 1);
      lcd.print("Rp.");
      lcd.print(beli);
    }
    else if (btn == 'B') {
      lcd.clear();
      beli = beli + 5000;
      lcd.setCursor(0, 0);
      lcd.print("BELI BBM : ");
      lcd.setCursor(0, 1);
      lcd.print("Rp.");
      lcd.print(beli);
    }
    else if (btn == 'C' && beli != 0) {
      for (j = 0; j <= 10; j++) {
        stringAngka[j] = NULL;
      }
      lcd.clear();
      beli = 0;
      i = 0;
      lcd.setCursor(0, 0);
      lcd.print("BELI BBM : ");
      lcd.setCursor(0, 1);
      lcd.print("Rp.");
      lcd.print(beli);

    }
    else if (btn == 'D') {
a:
      for (j = 0; j <= 10; j++) {
        stringAngka[j] = NULL;
        harga2[j] = NULL;
      }
      lcd.clear();
      harga5 = 0;
      beli = 0;
      pass = 0;
      i = 0;
      lcd.setCursor(0, 0);
      lcd.print("POM MINI");
      lcd.setCursor(0, 1);
      lcd.print("HARGA : Rp.");
      lcd.print(harga);
      lcd.print(" /L");
    }
    else if (btn == '#') {
      double hargaA = 0, beliA = 0;
      hargaA = harga, beliA = beli;
      double l = beliA / hargaA;
      harga3 = hargaA;;
      Serial.println(i);
      if (beli == 0) {
        lcd.clear();
        lcd.setCursor(0, 1);
        digitalWrite(relay, LOW);
        lcd.print("===MULAI MENGISI===");
        delay(2000);
        char tmbl;
        while (btn == '#') {
          tmbl = key.getKey();

          if (tmbl == 'D') {
            liter = 0;
            goto a;
          }
          Serial.print(tmbl);
          bbm_flow();
        }
      }
      else if (beli > 0) {
        lcd.clear();
        lcd.setCursor(0, 1);
        digitalWrite(relay, LOW);
        lcd.print("===MULAI MENGISI===");
        delay(2000);
        while (liter <= l) {
          bbm_flow();
        }
        lcd.clear();
        lcd.setCursor(0, 1);
        lcd.print("VOLUME : ");
        lcd.print(l);
        lcd.print(" L");
        lcd.setCursor(0, 2);
        lcd.print("Harga : Rp.");
        lcd.print(beli);
        harga4 = 0;
        liter = 0;
      }
    }
    else if (pass == 2199) {
      if (btn == '*') {
        pass = NULL;
        beli = NULL;
        goto a;
      }
      if (btn == 'D') {
        pass = NULL;
        beli = NULL;
        goto a;
      }
      else {
        beli = NULL;
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("UBAH HARGA");
        harga2[p] = btn;
        harga5 = atol(harga2);
        lcd.setCursor(0, 1);
        lcd.print("RP. ");
        lcd.print(harga5);
        Serial.println(harga5);
        Serial.println(pass);
        p++;
      }
    }
    else {
      stringAngka[i++] = btn;
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("BELI BBM : ");
      lcd.setCursor(0, 1);
      lcd.print("Rp.");
      beli = atol(stringAngka);
      lcd.print(beli);
      pass = beli;
    }
  }
}
void bbm_flow() {
  if ((millis() - oldTime) > 1000) {
    detachInterrupt(sensorInt);
    debit = ((1000.0 / (millis() - oldTime)) * pulseCount) / konstanta;
    oldTime = millis();
    flowmlt = (debit / 60) * 1000;
    volume += flowmlt;
    liter = volume / 1000;
    harga4 = liter * harga3;
    lcd.clear();
    lcd.setCursor(0, 1);
    lcd.print("VOLUME : ");
    lcd.print(liter);
    lcd.print(" L");
    lcd.setCursor(0, 2);
    lcd.print("Harga : Rp.");
    lcd.print(harga4);
    delay (100); pulseCount = 0;
    attachInterrupt(sensorInt, pulseCounter, FALLING);
  }
  delay(2000);
}
void pulseCounter() {
  pulseCount++;
}