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

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

// pin
#define FLOW_PIN 34          // Potentiometer for flow rate simulation
#define TRIG_PIN 19         // Ultrasonic trigger pin
#define ECHO_PIN 18         // Ultrasonic echo pin
#define BUZZER_PIN 4       // Buzzer pin
#define RESET_PIN 0 

float flowRate = 0.0;
float totalVolume = 0.0;

int tankLevel = 0;

bool lowLevelAlert = false;
bool enteringPlate = true;
bool kmEntered = false; 

String plateNumber = "";
String kmReading = "";
String Volume;  
String Flow;

LiquidCrystal_I2C lcd(0x27, 16, 2);
const int ledPin = 23;
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 colPins[COLS] = {26, 25, 33, 32};  
byte rowPins[ROWS] = {13, 12, 14, 27}; 
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

const char* ssid = "jawir";          
const char* password = "mawtauajah"; 
//const int potPin = 34;  

void setup() {
  lcd.init();
  lcd.backlight();
    
  pinMode(FLOW_PIN, INPUT);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(RESET_PIN, INPUT_PULLUP);
  pinMode(ledPin, OUTPUT);   // Set the LED pin as output
  digitalWrite(ledPin, LOW);

  Serial.begin(115200);
   WiFi.begin("Wokwi-GUEST", "", 6);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
    lcd.setCursor(0, 0);
    lcd.print("Please Wait");

  }
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Enter No. Unit:");

  Serial.println("Connected to WiFi");
}

void loop() {
  char key = keypad.getKey();

  if (key) {  // Check for valid key press
    if (key == '*') {
      // Reset inputs
      plateNumber = "";
      kmReading = "";
      enteringPlate = true;
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Enter Plate No:");
    } 
    else if (key == '#') 
    {
      if (enteringPlate && plateNumber.length() > 0) 
      {
        // Switch to KM input if Plate number is entered
        enteringPlate = false;
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("Enter KM:");
        lcd.setCursor(0, 1);
        lcd.print(kmReading);
      } 
      else if (!enteringPlate && kmReading.length() > 0) 
      {
        kmEntered = true;
        lcd.clear();
        //readFlowRate();
        
        
        
        displayInfo();
        send_data();
        checkTankLevel();
        
      }
    } else {
      if (enteringPlate) {
        plateNumber += key;
        lcd.setCursor(0, 1);
        lcd.print(plateNumber);
      } else {
        kmReading += key;
        lcd.setCursor(0, 1);
        lcd.print(kmReading);
      }
    }
  }

  if (digitalRead(RESET_PIN) == LOW) {
    plateNumber = "";
    kmReading = "";
    enteringPlate = true;
    kmEntered = false;
    lowLevelAlert = false;
    totalVolume = 0;
    flowRate = 0;
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Resetting...");
    delay(1000); // debounce delay for reset
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Enter No. Unit:");
  }
}

void displayInfo() {
  int potValue = analogRead(FLOW_PIN); 
  flowRate = map(potValue, 0, 4095, 0, 1000);  
  totalVolume += flowRate * 1 / 1000;  
  Volume = String(totalVolume);
  Flow = String(flowRate);
  Serial.println("VOL " + Volume);
  Serial.println("Flow " + Flow);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Flow: ");
  lcd.print(flowRate);
  lcd.print(" mL/s");

  lcd.setCursor(0, 1);
  lcd.print("Total: ");
  lcd.print(totalVolume, 2);
  lcd.print(" L");

  delay(1000);

  
}

void readFlowRate() {
  int potValue = analogRead(FLOW_PIN); 
  flowRate = map(potValue, 0, 4095, 0, 1000);  
  totalVolume += flowRate * 1 / 1000;  
  Volume = String(totalVolume);
  Flow = String(flowRate);

  Serial.println(Volume);
  Serial.println(Flow);
}

void checkTankLevel() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  long duration = pulseIn(ECHO_PIN, HIGH);
  tankLevel = duration * 0.034 / 2;
  if (tankLevel > 300) {  
    if (!lowLevelAlert) {
      lowLevelAlert = true;
      digitalWrite(BUZZER_PIN, HIGH);
      digitalWrite(ledPin, HIGH);  
    }
  } else {
    lowLevelAlert = false;
    digitalWrite(BUZZER_PIN, LOW);
    digitalWrite(ledPin, LOW); 
  }
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Tank Lvl: ");
  lcd.print(tankLevel);
  lcd.print(" cm");

  if (lowLevelAlert) {
    lcd.setCursor(0, 1);
    lcd.print("Warning: Low LvL!");
  }
}

void send_data() {
  // Display sending message on LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Sending Data...");
  
  // Data to send
  String Data1 = plateNumber;  
  String Data2 = kmReading;
  String Data3 = Flow;
  String Data4 = Volume;

  // Check WiFi connection status
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;

    // Construct the URL with query parameters
    String url = "https://script.google.com/macros/s/AKfycbyKBC0KReRrDaJxGVQqTYWsDXqOnIMfit8huBbvUwhYOxZDBMpRYAUOck2siONvbw0d/exec";
    url += "?value1=" + String(Data1);
    url += "&value2=" + String(Data2);
    url += "&value3=" + String(Data4);
    url += "&value4=" + String(Data3);

    // Begin HTTP GET request
    http.begin(url);
    int httpResponseCode = http.GET();

    // Check the response code
    if (httpResponseCode > 0) {
      String response = http.getString();  // Get response from server
      Serial.println("Response: " + response);  // Optional: log response for debugging
    } else {
      Serial.println("Error in sending data. HTTP Response Code: " + String(httpResponseCode));
    }

    // Close the HTTP connection
    http.end();
  } else {
    Serial.println("WiFi not connected");
  }

  // Optional: Add delay between sends if needed
  // delay(10000);
}