#define BLYNK_TEMPLATE_ID "TMPLkM1vxgYL"
#define BLYNK_TEMPLATE_NAME "WATER LEVEL"
#define BLYNK_AUTH_TOKEN "qWoARU2kypMJqngcysc274wkZIUIh_i8"

// WiFi credentials
char ssid[] = "Wokwi-GUEST";
char pass[] = "";

// Water level parameters (in cm)
const int emptyTankDistance = 90;  // 90 cm = 10%
const int fullTankDistance = 10;   // 10 cm = 100%

// Alarm trigger percentage
const int triggerPer = 10;

#include <Adafruit_SSD1306.h>
#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>

// Sensor connections
#define TRIGPIN    27
#define ECHOPIN    26
#define WIFI_LED    2
#define GREEN_LED   14

// Virtual pins for Blynk buttons
#define VPIN_BUTTON_1    V1
#define VPIN_BUTTON_2    V2

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 32

// OLED display configuration
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

float duration;
float distance;
int waterLevelPer;

char auth[] = BLYNK_AUTH_TOKEN;
BlynkTimer timer;

void checkBlynkStatus() {
  if (Blynk.connected()) {
    digitalWrite(WIFI_LED, HIGH);
  } else {
    digitalWrite(WIFI_LED, LOW);
  }
}

BLYNK_CONNECTED() {
  Blynk.syncVirtual(VPIN_BUTTON_1);
  Blynk.syncVirtual(VPIN_BUTTON_2);
}

void displayData(int value) {
  display.clearDisplay();
  display.setTextSize(4);
  display.setCursor(8, 2);
  display.print(value);
  display.print(" %");
  display.display();
}

void measureDistance() {
  // Send pulse to sensor
  digitalWrite(TRIGPIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIGPIN, HIGH);
  delayMicroseconds(20);
  digitalWrite(TRIGPIN, LOW);

  // Measure pulse duration
  duration = pulseIn(ECHOPIN, HIGH);
  distance = ((duration / 2) * 0.343) / 10;  // Convert to cm

  // Check if the distance is within range
  if (distance >= fullTankDistance && distance <= emptyTankDistance) {
    // Map the distance to water level percentage
    waterLevelPer = map(distance, fullTankDistance, emptyTankDistance, 100, 10);
    displayData(waterLevelPer);
    Blynk.virtualWrite(VPIN_BUTTON_1, waterLevelPer);
    Blynk.virtualWrite(VPIN_BUTTON_2, String(distance) + " cm");

    // Print distance for debugging
    Serial.print("Distance: ");
    Serial.print(distance);
    Serial.println(" cm");

    // If the water level is at or below 10 cm, blink the green LED for 5 seconds
    if (distance <= fullTankDistance) {
      digitalWrite(GREEN_LED, HIGH);
      delay(5000);  // LED stays on for 5 seconds
      digitalWrite(GREEN_LED, LOW);
    }
  } else {
    // If the distance is out of range (above the empty tank level), turn off the LED
    digitalWrite(GREEN_LED, LOW);
  }

  delay(100);  // Delay before repeating measurement
}

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

  // Pin setup
  pinMode(ECHOPIN, INPUT);
  pinMode(TRIGPIN, OUTPUT);
  pinMode(WIFI_LED, OUTPUT);
  pinMode(GREEN_LED, OUTPUT);

  // Initialize display
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    while (true);  // Halt execution if display fails to initialize
  }
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.clearDisplay();

  // Connect to WiFi
  WiFi.begin(ssid, pass);

  // Blynk and timer setup
  Blynk.config(auth);
  timer.setInterval(2000L, checkBlynkStatus);  // Check Blynk status every 2 seconds
}

void loop() {
  measureDistance();
  Blynk.run();
  timer.run();  // Run BlynkTimer tasks
}