/***
  Praktek 4 - Mentoring P5 - NTP OLED I MADE DENDY NIRAYANA
***/
#include <WiFi.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define 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 NTP_SERVER     "pool.ntp.org"
#define UTC_OFFSET     7 * 3600 // 3600 mendeskripsikan jam (1 jam = 3600) -> karna WIB merupakan UTC+7 maka OFFSET ditambah 7 jam
#define UTC_OFFSET_DST 0

void spinner() {
  static int8_t counter = 0;
  const char* glyphs = "\xa1\xa5\xdb";
  display.setCursor(64, 10);
  display.print(glyphs[counter++]);
  if (counter == strlen(glyphs)) {
    counter = 0;
  }
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 0);
  display.println("Connecting to ");
  display.setCursor(0, 10);
  display.print("WiFi ....");
  display.display();

}

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

  display.setCursor(64, 0);
  display.println(&timeinfo, "%H:%M:%S");

  display.setCursor(0, 10);
  display.println(&timeinfo, "%d/%m/%Y   WIB");
  display.display();
}

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

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 0);
  display.println("Nama: I MADE DENDY N.");
  display.println("NIM: 2102010009");
  display.println("Kelas: IoT 2");
  display.display();

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

  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 0);
  display.println("Online");
  display.setCursor(0, 10);
  display.println("Updating time...");
  display.display();
  configTime(UTC_OFFSET, UTC_OFFSET_DST, NTP_SERVER);

  Serial.println("");
  Serial.println("WiFi connected");
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
  display.clearDisplay();
}

void loop() {
  printLocalTime();
  delay(250);
}