#include <WiFi.h>
#include <esp_now.h> 

#define PIN_TRIG  3
#define PIN_ECHO 2

// Define the duty cycle period in seconds
#define TIME_TO_SLEEP 2
RTC_DATA_ATTR int bootCount = 0;

uint8_t brcAdr[] = {0x8C, 0xAA, 0xB5, 0x84, 0xFB, 0x90};
esp_now_peer_info_t peerInfo; 

 
void Sent_Data(const uint8_t *mac_addr, esp_now_send_status_t status) {
  Serial.print("Send Status: ");
  Serial.println(status == ESP_NOW_SEND_SUCCESS ? "Ok" : "Error");
}

//Receiving Callback
void OnDataRecv(const uint8_t * mac, const uint8_t *data, int len) {
  Serial.print("Message received: ");
  char receivedString[len+1];
  memcpy(receivedString, data, len);
  receivedString[len] = '\0';
  Serial.println(String(receivedString));
}


void staring_point()  {
    // Start a new measurement:
  digitalWrite(PIN_TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(PIN_TRIG, LOW);

  // Read the result:
  int duration = pulseIn(PIN_ECHO, HIGH);
  Serial.print("Distance in CM: ");
  int distance= duration / 58; 
  Serial.println(distance);
   
  // Determine parking spot status based on distance
  String status = (distance < 50) ? "OCCUPIED" : "FREE";

  //delay(1000);

  esp_now_send(brcAdr, (uint8_t*)&status[0], status.length());

}

void setup() {
  Serial.begin(115200);
  ++bootCount;
  
  pinMode(PIN_TRIG, OUTPUT);
  pinMode(PIN_ECHO, INPUT);

  WiFi.mode (WIFI_STA);
  esp_now_init();

  //send callback
  esp_now_register_send_cb(Sent_Data);
  //receive callback
  esp_now_register_recv_cb(OnDataRecv);

  // Peer Registration
  memcpy(peerInfo.peer_addr, brcAdr, 6);
  peerInfo.channel = 0;  
  peerInfo.encrypt = false;
  // Add peer (Is possible to register multiple peers)
  esp_now_add_peer(&peerInfo);

  staring_point();

  // esp_sleep_enable_timer_wakeup(DUTY_CYCLE_PERIOD*10 ); // Convert seconds to microseconds
  // Serial.flush(); 
  // esp_deep_sleep_start();


  esp_sleep_enable_timer_wakeup(TIME_TO_SLEEP*1000000 );
  Serial.println("ESP32 sleep every " + String(TIME_TO_SLEEP));

  Serial.flush(); 
  esp_deep_sleep_start();

}

void loop() {
  // // Start a new measurement:
  // digitalWrite(PIN_TRIG, HIGH);
  // delayMicroseconds(10);
  // digitalWrite(PIN_TRIG, LOW);

  // // Read the result:
  // int duration = pulseIn(PIN_ECHO, HIGH);
  // Serial.print("Distance in CM: ");
  // int distance= duration / 58; 
  // Serial.println(distance);
   
  // // Determine parking spot status based on distance
  // String status = (distance < 50) ? "OCCUPIED" : "FREE";

  // //delay(1000);

  // esp_now_send(brcAdr, (uint8_t*)&status[0], status.length());
  
  //   // Enter deep sleep mode for the duty cycle period
  // // esp_sleep_enable_timer_wakeup(DUTY_CYCLE_PERIOD ); // Convert seconds to microseconds
  // // esp_deep_sleep_start();
}