#define uS_TO_S_FACTOR 1000000ULL 
#define TIME_TO_SLEEP  300
  

#define BLYNK_PRINT Serial
#define maxRecords 1
#define LDRPIN  15

#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>

char auth[] = "";

char ssid[] = "";
char pass[] = "";

RTC_DATA_ATTR int last_ldrval = digitalRead(15);

RTC_DATA_ATTR int bootCount = 0;

void print_wakeup_reason(){
  esp_sleep_wakeup_cause_t wakeup_reason;

  wakeup_reason = esp_sleep_get_wakeup_cause();

  switch(wakeup_reason)
  {
    case ESP_SLEEP_WAKEUP_EXT0 : Serial.println("Wakeup caused by external signal using RTC_IO"); break;
    case ESP_SLEEP_WAKEUP_EXT1 : Serial.println("Wakeup caused by external signal using RTC_CNTL"); break;
    case ESP_SLEEP_WAKEUP_TIMER : Serial.println("Wakeup caused by timer"); break;
    case ESP_SLEEP_WAKEUP_TOUCHPAD : Serial.println("Wakeup caused by touchpad"); break;
    case ESP_SLEEP_WAKEUP_ULP : Serial.println("Wakeup caused by ULP program"); break;
    default : Serial.printf("Wakeup was not caused by deep sleep: %d\n",wakeup_reason); break;
  }
}

void setup()
{
  setCpuFrequencyMhz(80);
  Serial.begin(9600);
  delay(10);

  ++bootCount;
  Serial.println("Boot number: " + String(bootCount));

  print_wakeup_reason();
  esp_sleep_enable_timer_wakeup(TIME_TO_SLEEP * uS_TO_S_FACTOR);
  Serial.println("Setup ESP32 to sleep for every " + String(TIME_TO_SLEEP) + " Seconds");

  Serial.print("Connecting to ");
  Serial.println(ssid);
    WiFi.begin(ssid, pass);
  int wifit_ctr = 0;
  while (WiFi.status() != WL_CONNECTED) 
  {
    delay(500);
    Serial.print(".");
  }
  Serial.println("WiFi connected");
  Blynk.begin(auth, ssid, pass);

  Blynk.run(); 
  //read input on digital pin 15:
  int ldrval = digitalRead(15); //LDR
  Serial.print("LDR: "); Serial.println(ldrval);
  Serial.print("LDR_1: "); Serial.println(last_ldrval);

  if (ldrval != last_ldrval) 
  {
     Blynk.notify("Alert Power!"); 
    }
    last_ldrval = ldrval;
    delay(500);

  Serial.println("Going to sleep now");
  Serial.flush(); 
  esp_deep_sleep_start();
}

void loop(){
  //This is not going to be called
}