#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <esp_now.h>
#include <WiFi.h>

const int SCREEN_WIDTH = 128; // OLED display width, in pixels
const int SCREEN_HEIGHT = 64; // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

#define SCREEN_ADDRESS 0x3C

// REPLACE WITH THE MAC Address of your sender
uint8_t senderAddress[] = {0x24, 0x0A, 0xC4, 0x00, 0x01, 0x10};

typedef struct struct_message
{
  float waterLevel;
} struct_message;

struct_message waterLevelReading;

void OnDataRecv(const uint8_t *mac, const uint8_t *incomingData, int len)
{
  memcpy(&waterLevelReading, incomingData, sizeof(waterLevelReading));
}

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

  // Init OLED display
  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS))
  {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;)
      ;
  }

  display.display();
  delay(2000);
  display.clearDisplay();

  // Set device as a Wi-Fi Station
  WiFi.mode(WIFI_STA);

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

  // Register callback for receiving data
  esp_now_register_recv_cb(OnDataRecv);

  // Add peer
  esp_now_peer_info_t peerInfo;
  memcpy(peerInfo.peer_addr, senderAddress, 6);
  peerInfo.channel = 0;
  peerInfo.encrypt = false;

  if (esp_now_add_peer(&peerInfo) != ESP_OK)
  {
    Serial.println("Failed to add peer");
    return;
  }
}

void loop()
{
  // Display water level on OLED
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 0);
  display.print("Water Level: ");
  display.print(waterLevelReading.waterLevel);
  display.display();

  delay(5000); // Adjust the delay as needed
}