// ==== Slave ====
#include "BluetoothSerial.h"

BluetoothSerial SerialBT;

void setup() {
  Serial.begin(115200);
  SerialBT.begin("ESP32_SLAVE"); // Bluetooth device name
  Serial.println("The device started, now you can pair it with Bluetooth!");
  Serial.println(BluetoothDeviceAddress().toString().c_str()); // Print Slave mac address
}

void loop() {
  if (SerialBT.available()) {
    char incomingChar = SerialBT.read();
    Serial.print("Received: ");
    Serial.println(incomingChar);
    // Optionally, echo back to master
    SerialBT.write(incomingChar);
  }
}
// ====================================

// ==== Master ====
#include "BluetoothSerial.h"

BluetoothSerial SerialBT;

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

  // MAC address of the slave ESP32 (you need to set it from the slave serial output or BT scan)
  const char *slaveAddress = "AA:BB:CC:11:22:33"; // Replace with your slave MAC address!

  if (!SerialBT.begin("ESP32_MASTER", true)) { // true = Master mode
    Serial.println("An error occurred initializing Bluetooth");
    return;
  }

  Serial.println("Bluetooth started in master mode. Connecting to slave...");
  if (SerialBT.connect(slaveAddress)) {
    Serial.println("Connected to slave successfully!");
  } else {
    Serial.println("Failed to connect. Make sure slave is on and in range.");
    while (1) delay(1000); // Stop here
  }
}

void loop() {
  // Send data every second
  SerialBT.println("Hello from Master!");
  Serial.println("Sent: Hello from Master!");
  delay(1000);

  // Optional: read data sent back from slave
  while (SerialBT.available()) {
    char c = SerialBT.read();
    Serial.print("Slave echoed: ");
    Serial.println(c);
  }
}
// ====================================

// ==== Print Slave mac address ====
#include "BluetoothSerial.h"

void setup() {
  Serial.begin(115200);
  delay(1000); // Wait for Serial to initialize

  // Start Bluetooth (name doesn't matter here)
  BluetoothSerial SerialBT;
  SerialBT.begin("GetMAC");

  // Get and print the MAC address
  const uint8_t* mac = ESP_BT_DEV_MAC_ADDR;
  Serial.print("Bluetooth MAC address: ");
  for (int i = 0; i < 6; i++) {
    if (mac[i] < 16) Serial.print("0");
    Serial.print(mac[i], HEX);
    if (i < 5) Serial.print(":");
  }
  Serial.println();
}

void loop() {
  // Nothing to do here
}