#include <ESP8266WiFi.h>   // initializing the required resource libraries
#include <espnow.h>       
uint8_t broadcastAddress[] = {0x30,0x30,0xF9,0x17,0xF8,0x94};  // Secondary's MAC Address 84:f3:eb:e1:57:fd


#define BUTTON_PIN 13  // The ESP8266 pin D7 connected to button


typedef struct struct_message {                     //create a structure called "message" and add the contents of the message
  int btnstate;                                    //integer value "c"            
} struct_message;                                        


struct_message myData;       
                       // Create a struct_message called myData
unsigned long lastTime = 0; 
unsigned long timerDelay = 1000;  // send readings timer

void OnDataSent(uint8_t *mac_addr, uint8_t sendStatus) {
  Serial.print("Last Packet Send Status: ");
  if (sendStatus == 0){
    Serial.println("Delivery success");
  }
  else{
    Serial.println("Delivery fail");
  }
}

void setup() {
  Serial.begin(115200);   // Init Serial Monitor
  WiFi.mode(WIFI_STA);   // Set device as a Wi-Fi Station

  // Init ESP-NOW
  if (esp_now_init() != 0) {
    Serial.println("Error initializing ESP-NOW");
    return;
  }

  // Once ESPNow is successfully Init, we will register for Send CB to
  // get the status of Trasnmitted packet
  esp_now_set_self_role(ESP_NOW_ROLE_CONTROLLER);
  esp_now_register_send_cb(OnDataSent);
  
  // Register peer
  esp_now_add_peer(broadcastAddress, ESP_NOW_ROLE_SLAVE, 1, NULL, 0);
  // Initialize the Serial to communicate with the Serial Monitor.

  pinMode(BUTTON_PIN, INPUT_PULLUP); // Configure the ESP8266 pin as a pull-up input: HIGH when the button is open, LOW when pressed.
}

void loop() {
  if ((millis() - lastTime) > timerDelay) {
 
  //int button_state = digitalRead(BUTTON_PIN);  // read the state of the switch/button:
  myData.btnstate = digitalRead(BUTTON_PIN); 
  Serial.println(myData.btnstate); // print out the button's state
 esp_now_send(broadcastAddress, (uint8_t *) &myData, sizeof(myData));
 lastTime = millis();
  
}
}