#include <ArduinoBLE.h>

BLEService myService("19b10000-e8f2-537e-4f6c-d104768a1214");

BLECharacteristic myStringChar("19b10000-e8f2-537e-4f6c-d104768a1214",
                               BLERead | BLEWrite | BLENotify,
                               32);  // up to 32-byte string

void setup() {
  Serial.begin(115200);
 // while (!Serial);
  delay(15000);
  Serial.println("waited 15 seconds");

  if (!BLE.begin()) {
    Serial.println("BLE failed to start");
    while (1);
  }

  BLE.setLocalName("PortentaStringBLE");
  BLE.setAdvertisedService(myService);

  myService.addCharacteristic(myStringChar);
  BLE.addService(myService);

  myStringChar.writeValue("ready");
  BLE.advertise();

  Serial.println("BLE String Service Started");
}

void loop() {
  BLEDevice central = BLE.central();

  if (central) {
    Serial.print("Connected to: ");
    Serial.println(central.address());

    while (central.connected()) {
      if (myStringChar.written()) {
        // Receive incoming string
        int len = myStringChar.valueLength();
        uint8_t buffer[33] = {0};  // +1 for null terminator
        myStringChar.readValue(buffer, len);
        buffer[len] = '\0';  // Ensure null termination
        String incoming = (char*)buffer;

        Serial.print("Web says: ");
        Serial.println(incoming);

        // Respond
        if (incoming == "start") {
          myStringChar.writeValue("working");  // This triggers notify if started on client
          Serial.println("Sent: working");
        } else if (incoming == "stop") {
          myStringChar.writeValue("done");
          Serial.println("Sent: done");
        } else {
          myStringChar.writeValue("unknown");
          Serial.println("Sent: unknown");
        }
      }
    }

    Serial.println("Disconnected.");
  }
}