#include <Wire.h>
#include <U8g2lib.h>

// ================= DISPLAY =================
U8G2_SSD1306_128X64_NONAME_F_HW_I2C display(U8G2_R0, U8X8_PIN_NONE, 6, 5);

// ================= BIT SWAP FUNCTION =================
uint8_t swapBits(uint8_t b) {
  b = (b & 0xF0) >> 4 | (b & 0x0F) << 4;
  b = (b & 0xCC) >> 2 | (b & 0x33) << 2;
  b = (b & 0xAA) >> 1 | (b & 0x55) << 1;
  return b;
}

// ===== THUNDER ICON =====
const unsigned char icon_thunder_18[] PROGMEM = {
  0x00,0x00,0x00,0x00,0x00,0x3f,0xc0,0x00,0x00,0x7d,0xe0,0x00,0x00,0xe0,0x70,0x00,
  0x0f,0xc0,0x38,0x00,0x0f,0x80,0x18,0x00,0x1c,0x00,0x1c,0x00,0x38,0x60,0x0e,0x00,
  0x7b,0xf8,0x0f,0x00,0xe3,0xf8,0x03,0x80,0xc1,0xf8,0x01,0x80,0xc3,0xf8,0x01,0x80,
  0xc0,0x60,0x01,0x80,0xc0,0x6c,0x01,0x80,0xe0,0x3f,0x03,0x80,0xfe,0x3f,0x7f,0x80,
  0x3e,0x3f,0xfe,0x00,0x00,0xbf,0x00,0x00,0x01,0x8c,0x00,0x00,0x07,0xf4,0x00,0x00,
  0x07,0xe0,0x00,0x00,0x07,0xe0,0x00,0x00,0x07,0xf0,0x00,0x00,0x01,0x80,0x00,0x00,
  0x00,0x00,0x00,0x00
};

uint8_t icon_thunder_18_swapped[sizeof(icon_thunder_18)];

// ================= DATE ROTATION =================
unsigned long dateTimer = 0;
int dateStage = 0; // 0=day+date, 1=month, 2=year

String getDayName(int d){
  const char* days[] = {"SUN","MON","TUES","WEDNES","THURS","FRI","SATAR"};
  return String(days[d]);
}

String getMonthName(int m){
  const char* months[] = {"JAN","FEB","MAR","APR","MAY","JUN",
                          "JUL","AUG","SEP","OCT","NOV","DEC"};
  return String(months[m]);
}

// ================= FAKE DATA =================
String weatherDesc = "Sunny";
String savedCity   = "Dhaka";

float outdoorTemp = 32;
float indoorTemp  = 28;
int indoorHum     = 65;

// ===== FAKE STATUS =====
int fakeRSSI = -60;     // WiFi strength
int fakeBattery = 75;   // Battery %

// ================= TIMER =================
unsigned long lastSecond = 0;
unsigned long textTimer  = 0;

int hh = 12, mm = 45, ss = 0;
bool showCity = false;

// ================= SCROLL =================
int scrollX = 0;
String scrollText = "";

// =================================================
// ===== WIFI ICON =====
int getWiFiLevel() {
  if(fakeRSSI >= -55) return 4;
  if(fakeRSSI >= -65) return 3;
  if(fakeRSSI >= -75) return 2;
  if(fakeRSSI >= -85) return 1;
  return 0;
}

void drawWiFiIcon(int x, int y) {
  int level = getWiFiLevel();

  for(int i=0;i<4;i++){
    if(i < level)
      display.drawBox(x + i*3, y - i*2, 2, i*2 + 2);
    else
      display.drawFrame(x + i*3, y - i*2, 2, i*2 + 2);
  }
}

// =================================================
// ===== BATTERY ICON =====
void drawBatteryIcon(int x, int y) {

  int w = 14;   // reduced width (fits WiFi width)
  int h = 7;    // reduced height (was ~8 → now -3px)

  // Battery body
  display.drawFrame(x, y, w, h);

  // Battery head (smaller)
  display.drawBox(x + w, y + 2, 2, 3);

  // Fill level
  int fill = map(fakeBattery, 0, 100, 0, w - 2);
  display.drawBox(x + 1, y + 1, fill, h - 2);
}

// =================================================
void setup() {
  display.begin();
  display.setFont(u8g2_font_logisoso20_tr);

  scrollText = weatherDesc;

  // Convert icon once
  for (int i = 0; i < sizeof(icon_thunder_18); i++) {
    uint8_t b = pgm_read_byte(&icon_thunder_18[i]);
    icon_thunder_18_swapped[i] = swapBits(b);
  }
}

// =================================================
void loop() {

  // CLOCK
  if (millis() - lastSecond >= 1000) {
    lastSecond = millis();
    ss++;

    if (ss >= 60) {
      ss = 0;
      mm++;
      if (mm >= 60) {
        mm = 0;
        hh++;
        if (hh >= 24) hh = 0;
      }
    }
  }

  // TEXT ROTATION
  if (showCity) {
    if (millis() - textTimer > 3000) {
      showCity = false;
      textTimer = millis();
      scrollText = weatherDesc;
      scrollX = 0;
    }
  } else {
    if (millis() - textTimer > 4000) {
      showCity = true;
      textTimer = millis();
      scrollText = savedCity;
      scrollX = 0;
    }
  }
  
  // ===== DATE ROTATION =====
  //if(millis() - dateTimer > 2400){
   // dateStage++;
    //if(dateStage > 1) dateStage = 0;
   // dateTimer = millis();
  //}*/
  drawUI();
}

// =================================================
void drawUI() {

  display.clearBuffer();

  // ===== STATUS BAR =====
  drawWiFiIcon(0, 6);        // LEFT
  drawBatteryIcon(112, 0);    // RIGHT

    // ===== TOP CENTER DATE =====
  struct tm timeinfo;
  //getLocalTime(&timeinfo);

  timeinfo.tm_wday = 1;   // Monday
  timeinfo.tm_mday = 06;
  timeinfo.tm_mon  = 3;   // April (0-based)
  timeinfo.tm_year = 126; // 2026 (1900+126)

  String dateText;

  if(dateStage == 0){
    // Mon 17
    dateText = dateText = getMonthName(timeinfo.tm_mon) + " " +getDayName(timeinfo.tm_wday) + " " + String(timeinfo.tm_mday);
  }
  //else{
    // Apr 2026
  //  dateText = getMonthName(timeinfo.tm_mon) + " " + String(1900 + timeinfo.tm_year);
 // }


  // Draw centered
  display.setFont(u8g2_font_profont10_tr);
  int dtWidth = display.getStrWidth(dateText.c_str());
  int dtX = (128 - dtWidth) / 2;

  display.setCursor(dtX, 7);
  display.print(dateText);

  // ===== CLOCK =====
 /* char timeStr[9];
  sprintf(timeStr, "%02d:%02d:%02d", hh, mm, ss);

  display.setFont(u8g2_font_fub20_tf);
  int textWidth = display.getStrWidth(timeStr);
  int x = (128 - textWidth) / 2;

  display.setCursor(x, 32);
  display.print(timeStr);
*/

  // ===== CLOCK (12H + AM/PM + SMALL SECONDS) =====

// Convert to 12-hour format
// ===== CLOCK (MODIFIED LAYOUT) =====

// Convert to 12-hour format
int displayHour = hh % 12;
if (displayHour == 0) displayHour = 12;

bool isPM = (hh >= 12);

// Main time (HH:MM)
char timeMain[6];
sprintf(timeMain, "%02d:%02d", displayHour, mm);

// Seconds
char secStr[3];
sprintf(secStr, "%02d", ss);

// AM/PM
const char* ampm = isPM ? "PM" : "AM";

// ===== Draw Main Time =====
display.setFont(u8g2_font_fub20_tf);
int mainWidth = display.getStrWidth(timeMain);

// Keep same center alignment as before
int baseX = (128 - (mainWidth + 28)) / 2;  
// +28 ≈ space for seconds area (adjust if needed)

display.setCursor(baseX+4, 32);
display.print(timeMain);

// ===== RIGHT SIDE (OLD SECONDS AREA) =====
int secAreaX = baseX + mainWidth + 2;

// AM/PM (TOP)
display.setFont(u8g2_font_spleen6x12_mr);
display.setCursor(secAreaX+6, 20);
display.print(ampm);

// Seconds (BOTTOM)
display.setFont(u8g2_font_spleen6x12_mr);
display.setCursor(secAreaX+6, 32);
display.print(secStr);

///////////////////////////////////
  // Divider
  display.drawLine(0, 35, 128, 35);
  display.drawLine(64, 38, 64, 64);

  // ================= LEFT =================
  int iconX = 1;
  int iconY = 40;
  int iconW = 25;

  display.drawXBM(iconX, iconY, 25, 25, icon_thunder_18_swapped);

  display.setFont(u8g2_font_ncenB08_tr);
  int tempX = iconX + iconW + 5;

  display.setCursor(tempX, 50);
  display.printf("%.0f\xB0""C", outdoorTemp);

  // SCROLL TEXT
  display.setFont(u8g2_font_6x10_tr);

  int textStartX = tempX;
  int textEndX = 62;
  int textY = 60;

  int textWidth2 = display.getStrWidth(scrollText.c_str());

  if (textWidth2 <= (textEndX - textStartX)) {
    display.setCursor(textStartX, textY);
    display.print(scrollText);
  } else {
    display.setClipWindow(textStartX, textY - 10, textEndX, textY);

    display.setCursor(textStartX - scrollX, textY);
    display.print(scrollText);

    display.setMaxClipWindow();

    scrollX++;
    if (scrollX > textWidth2 + 10) scrollX = 0;
  }

  // ================= RIGHT =================
  int centerX = 64 + (128 - 64) / 2;

  display.setFont(u8g2_font_6x10_tr);
  display.setCursor(centerX - 20, 48);
  display.print("Indoor");

  display.setFont(u8g2_font_ncenB08_tr);
  char indoorStr[20];
  sprintf(indoorStr, "%.0f\xB0""C / %d%%", indoorTemp, indoorHum);

  display.setCursor(centerX - display.getStrWidth(indoorStr)/2, 60);
  display.print(indoorStr);

  display.sendBuffer();
}