#include <LiquidCrystal_I2C.h>
//#include <Wire.h>
#include <NTPClient.h>
#include <WiFi.h>

#define NTP_SERVER     "pool.ntp.org"
#define UTC_OFFSET     5 * 3600
#define UTC_OFFSET_DST 0

const int RSSI_MAX =-30;// define maximum strength of signal in dBm
const int RSSI_MIN =-90;// define minimum strength of signal in dBm
String Signals;

LiquidCrystal_I2C lcd1(0x27, 16, 2);
const byte LED = 13;

byte noSignals[] = {B10001, B01010, B00100, B01010, B10001, B00000, B01000, B11000};
byte weekSignals[] = {B00000, B00000, B00000, B00000, B00000, B01000, B11000, B11000};
byte normalSignals[] = {B00000, B00000, B00000, B00010, B00110, B01110, B11110, B11110};
byte strongSignals[] = {B00000, B00000, B00001, B00011, B00111, B01111, B11111, B11111};

void spinner() {
  static int8_t counter = 0;
  const char* glyphs = "\xa1\xa5\xdb";
  lcd1.setCursor(15, 1);
  lcd1.print(glyphs[counter++]);
  if (counter == strlen(glyphs)) {
    counter = 0;
  }
}

void printLocalTime() {
  struct tm timeinfo;
  if (!getLocalTime(&timeinfo)) {
    lcd1.setCursor(0, 1);
    lcd1.println("Connection Err");
    return;
  }

  lcd1.setCursor(8, 0);
  lcd1.println(&timeinfo, "%H:%M:%S");

  lcd1.setCursor(0, 1);
  lcd1.println(&timeinfo, "%d/%m/%Y   %Z");
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  //Serial.println("Hello, ESP32-S3!");
  //Wire.begin(8,9);
  lcd1.init();
  lcd1.backlight();
  lcd1.setCursor(1, 0);
  lcd1.print("Hello, world !");
  lcd1.setCursor(2, 1);
  lcd1.print("ESP32-S3 I2C");
  
  pinMode(LED, OUTPUT);
  lcd1.setCursor(0, 0);
  lcd1.print("Connecting to WiFi");
  WiFi.begin("Wokwi-GUEST", "", 6);
  String sDot = ".";
  while (WiFi.status() != WL_CONNECTED) {
    delay(100);    
    lcd1.setCursor(0, 1);
    lcd1.print(sDot);
    sDot += ".";
    if (sDot == ".................") {
      lcd1.clear();
      sDot = ".";
    }
  }
  lcd1.setCursor(0, 1);
  lcd1.print("Connected!");
  
  Serial.begin(115200);

  lcd1.init();
  lcd1.backlight();
  lcd1.setCursor(0, 0);
  lcd1.print("Connecting to ");
  lcd1.setCursor(0, 1);
  lcd1.print("WiFi ");

  WiFi.begin("Wokwi-GUEST", "", 6);
  WiFi.RSSI();
  while (WiFi.status() != WL_CONNECTED) {
    delay(250);
    spinner();
  }

  lcd1.clear();
  lcd1.setCursor(0, 0);
  lcd1.println("Online");
  lcd1.setCursor(0, 1);
  lcd1.println("Updating time...");

  configTime(UTC_OFFSET, UTC_OFFSET_DST, NTP_SERVER);

}

void loop() {

if (WiFi.status() == WL_CONNECTED) { // If WiFi is connected
    int rssi = WiFi.RSSI(); // Get the signal strength in dBm
    dBmtoPercentage(rssi);    
    delay(1000); // Wait for a second
    printLocalTime();
}
}

void dBmtoPercentage(int dBm)
{
    if(dBm <= RSSI_MIN)
    {
        lcd1.setCursor(0, 0);
        lcd1.println("NoWiFi");
        lcd1.createChar(0, noSignals);
        lcd1.setCursor(6,0);
        lcd1.write(0);        
    }
    else if(dBm >= RSSI_MAX)
    {  
        lcd1.setCursor(0, 0);
        lcd1.println("Online");
        lcd1.createChar(0, weekSignals);
        lcd1.setCursor(6,0);
        lcd1.write(0);        
    }
    else if ((2 * (dBm + 100)) > 25 && (2 * (dBm + 100)) < 50)
    {
        lcd1.setCursor(0, 0);
        lcd1.println("Online");
        lcd1.createChar(0, normalSignals);
        lcd1.setCursor(6,0);
        lcd1.write(0);      
        //quality = 2 * (dBm + 100);
   }
    else if ((2 * (dBm + 100)) > 50 && (2 * (dBm + 100)) < 75)
    {
      lcd1.setCursor(0, 0);
      lcd1.println("Online");
      lcd1.createChar(0, strongSignals);
      lcd1.setCursor(6,0);
      lcd1.write(0);      
        //quality = 2 * (dBm + 100);
   }
    // return quality;
}//dBmtoPercentage