#define BLYNK_PRINT Serial

/************ BLYNK CONFIGURATION ************/

#define BLYNK_TEMPLATE_ID "TMPL2PAhKRuXi"
#define BLYNK_TEMPLATE_NAME "Week15"
#define BLYNK_AUTH_TOKEN "8UtXxMqDvQbu-QKcqCdu-JdQm0BNU-DM"

/************ LIBRARIES ************/
#include <WiFi.h>
#include <BlynkSimpleEsp32.h>

/************ WIFI DATA ************/
char ssid[] = "STAR LABS";
char pass[] = "$t@rLAB5";

/************ HARDWARE PINS ************/
#define SHARP_PIN A0     // Sharp analog distance sensor
#define MOTOR_IN1 D1     // L9110S input A / IN1
#define MOTOR_IN2 D2     // L9110S input B / IN2
#define LED_PIN   D10    // LED on the PCB

/************ BLYNK TIMER ************/
BlynkTimer timer;

/************ VARIABLES ************/
float distanceCm = 0.0;
int motorState = 0;

float readSharpDistance()
{
  int rawValue = analogRead(SHARP_PIN);

  // ESP32 ADC range is usually 0 to 4095
  float voltage = rawValue * (3.3 / 4095.0);

  // Avoid division problems with very low voltage
  if (voltage < 0.1) {
    return 999.0;
  }

  // Approximate conversion for Sharp IR distance sensor
  float distance = 27.86 * pow(voltage, -1.15);

  return distance;
}

/****************************************************
   Motor control functions
****************************************************/
void motorOn()
{
  digitalWrite(MOTOR_IN1, HIGH);
  digitalWrite(MOTOR_IN2, LOW);

  digitalWrite(LED_PIN, HIGH);

  motorState = 1;
}

void motorOff()
{
  digitalWrite(MOTOR_IN1, LOW);
  digitalWrite(MOTOR_IN2, LOW);

  digitalWrite(LED_PIN, LOW);

  motorState = 0;
}


void updateSystem()
{
  distanceCm = readSharpDistance();

  Serial.print("Distance: ");
  Serial.print(distanceCm);
  Serial.println(" cm");

  if (distanceCm >= 15.0 && distanceCm <= 20.0) {
    motorOn();

    Serial.println("Object detected in range: MOTOR ON / LED ON");

    Blynk.virtualWrite(V2, "Object in range - Motor ON");
  } 
  else {
    motorOff();

    Serial.println("Object out of range: MOTOR OFF / LED OFF");

    Blynk.virtualWrite(V2, "Out of range - Motor OFF");
  }

  // Send values to Blynk
  Blynk.virtualWrite(V0, distanceCm);
  Blynk.virtualWrite(V1, motorState);
}

/****************************************************
   SETUP
****************************************************/
void setup()
{
  Serial.begin(115200);
  delay(1000);

  Serial.println();
  Serial.println("====================================");
  Serial.println("XIAO ESP32-C6 + Blynk + Sharp Sensor");
  Serial.println("Input: Sharp sensor on A0");
  Serial.println("Output: Motor L9110S on D1/D2");
  Serial.println("Output: LED on D10");
  Serial.println("====================================");

  pinMode(SHARP_PIN, INPUT);

  pinMode(MOTOR_IN1, OUTPUT);
  pinMode(MOTOR_IN2, OUTPUT);
  pinMode(LED_PIN, OUTPUT);

  motorOff();

  Serial.println("Connecting to WiFi and Blynk...");
  Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);

  Serial.println("System ready.");

  // Update system every 500 ms
  timer.setInterval(500L, updateSystem);
}

/****************************************************
   LOOP
****************************************************/
void loop()
{
  Blynk.run();
  timer.run();
}