#include <TFT_eSPI.h> // Hardware-specific library
#include <SPI.h>

#define TFT_GREY 0x5AEB

TFT_eSPI tft = TFT_eSPI();       // Invoke custom library

uint32_t targetTime = 0;                    // for next 1 second timeout

static uint8_t conv2d(const char* p); // Forward declaration needed for IDE 1.6.x

uint8_t hh = conv2d(__TIME__), mm = conv2d(__TIME__ + 3), ss = conv2d(__TIME__ + 6); // Get H, M, S from compile time

byte omm = 99, oss = 99;
byte xcolon = 0, xsecs = 0;
unsigned int colour = 0;

void setup(void) {
  Serial.begin(115200); // Enable serial debugging
  tft.init();
  tft.setRotation(1);
  tft.fillScreen(TFT_WHITE);

  tft.setTextSize(1);
  tft.setTextColor(TFT_BLACK, TFT_WHITE);

  // Draw static elements
  tft.drawCentreString("PM", 30, 30, 2); // "PM" at the top-left corner
  tft.drawCentreString("IXLens", 160, 30, 2); // "IXLens" at the top-center
  tft.drawCentreString("🔔", 290, 30, 2); // Bell icon at the top-right corner

  tft.drawCentreString("815°F", 40, 220, 2); // Bottom-left text
  tft.drawCentreString("27 Dec 21", 160, 220, 2); // Bottom-center date
  tft.drawCentreString("CODICOL AL", 280, 220, 2); // Bottom-right text

  targetTime = millis() + 1000;
}

void loop() {
  if (targetTime < millis()) {
    targetTime = millis() + 1000;

    ss++;
    if (ss == 60) {
      ss = 0;
      omm = mm;
      mm++;
      if (mm > 59) {
        mm = 0;
        hh++;
        if (hh > 23) {
          hh = 0;
        }
      }
    }

    int xpos = 70;
    int ypos = 85;
    int ysecs = ypos + 17;

    if (omm != mm) {
      omm = mm;
      tft.fillRect(0, ypos, tft.width(), 48, TFT_WHITE);
      tft.setTextColor(TFT_BLACK, TFT_WHITE);
      
      if (hh < 10) xpos += tft.drawChar('0', xpos, ypos, 6);
      xpos += tft.drawNumber(hh, xpos, ypos, 6);
      xcolon = xpos;
      xpos += tft.drawChar(':', xpos, ypos, 6);
      if (mm < 10) xpos += tft.drawChar('0', xpos, ypos, 6);
      xpos += tft.drawNumber(mm, xpos, ypos, 6);
      xsecs = xpos;
      tft.drawCentreString("Wednesday", (tft.width() / 2)-10, ypos + 48, 4);
    }

    if (oss != ss) {
      oss = ss;
      xpos = xsecs;

      if (ss % 2) {
        tft.setTextColor(TFT_GREY, TFT_WHITE);
        tft.drawChar(':', xcolon, ypos, 6);
        xpos += tft.drawChar(' ', xsecs, ysecs, 4);
        tft.setTextColor(TFT_BLACK, TFT_WHITE);
      } else {
        tft.drawChar(':', xcolon, ypos, 6);
        xpos += tft.drawChar(' ', xsecs, ysecs, 4);
      }

      if (ss < 10) xpos += tft.drawChar('0', xpos, ysecs, 4);
      tft.drawNumber(ss, xpos, ysecs, 4);
    }
  }
}

// Function to extract numbers from compile time string
static uint8_t conv2d(const char* p) {
  uint8_t v = 0;
  if ('0' <= *p && *p <= '9')
    v = *p - '0';
  return 10 * v + *++p - '0';
}