#include "BluetoothSerial.h"


// Check if Bluetooth configs are enabled
#if !defined(CONFIG_BT_ENABLED) || !defined(CONFIG_BLUEDROID_ENABLED)
#error Bluetooth is not enabled! Please run `make menuconfig` to and enable it
#endif

// Bluetooth Serial object
BluetoothSerial SerialBT;

// GPIO where LED is connected to
const int ledPin =  13;
// Handle received and sent messages
String message = "";
char incomingChar;

void setup() {
  pinMode(ledPin, OUTPUT);
  Serial.begin(115200);
  // Bluetooth device name
  SerialBT.begin("ESP32");
  Serial.println("The device started, now you can pair it with bluetooth!");
}

void loop() {
    // put your main code here, to run repeatedly:


  // Read received messages (LED control command)
  if (SerialBT.available()){
    char incomingChar = SerialBT.read();
    if (incomingChar != '\n'){
      message += String(incomingChar);
    }
    else{
      message = "";
    }
    Serial.write(incomingChar);  
  }
  // Check received message and control output accordingly
  if (message =="1"){
 
    const char* myStr = "1"; // the string(RESPONSE) to be sent to cell phone  via bluetooth
    //converts the string to uint8_t type
    uint8_t ledState = static_cast<uint8_t>(myStr[0]);
    digitalWrite(ledPin, HIGH);
    SerialBT.write(ledState); //send messages to my phone. 1
  
}
else if (message =="0"){
    const char* myStr = "0"; // the string(RESPONSE) to be sent to cell phone via bluetooth
    //converts the string to uint8_t type
    uint8_t ledState = static_cast<uint8_t>(myStr[0]);
    digitalWrite(ledPin, LOW);
    SerialBT.write(ledState); // Sends message to my phone. 0 
 
  }
  delay(20);
}