#include <GxEPD2_3C.h>
#include <Adafruit_GFX.h>
#include <Fonts/FreeMonoBold12pt7b.h>
#include <Fonts/FreeMonoBold9pt7b.h>

SPIClass hspi(HSPI);
// Set up the e-paper display
GxEPD2_3C<GxEPD2_290_C90c, GxEPD2_290_C90c::HEIGHT> display(GxEPD2_290_C90c(/*CS=*/ 5, /*DC=*/ 4, /*RST=*/ 21, /*BUSY=*/ 22));
const char HelloWorld[] = "Hello World!";

void helloWorld()
{
  //Serial.println("helloWorld");
  display.setRotation(1);
  display.setFont(&FreeMonoBold9pt7b);
  display.setTextColor(GxEPD_BLACK);
  int16_t tbx, tby; uint16_t tbw, tbh;
  display.getTextBounds(HelloWorld, 0, 0, &tbx, &tby, &tbw, &tbh);
  // center bounding box by transposition of origin:
  uint16_t x = ((display.width() - tbw) / 2) - tbx;
  uint16_t y = ((display.height() - tbh) / 2) - tby;
  display.setFullWindow();
  display.firstPage();
  do
  {
    display.fillScreen(GxEPD_WHITE);
    display.setCursor(x, y);
    display.print(HelloWorld);
  }
  while (display.nextPage());
  //Serial.println("helloWorld done");
}


void setup() {
  Serial.begin(115200);
  hspi.begin(18, -1, 19, -1);
display.epd2.selectSPI(hspi, SPISettings(2500000, MSBFIRST, SPI_MODE0));
  
  // Initialize the e-paper display
  display.init();
  display.setRotation(1);
}

void loop() {
  /*
  // Clear the display
  display.fillScreen(GxEPD_WHITE);

  // Draw "Hello World" in the center of the display
  display.setFont(&FreeMonoBold12pt7b);
  display.setTextColor(GxEPD_BLACK);
  display.setCursor((display.width() - 11) / 2, display.height() / 2);
  display.println("Hello World");

  // Update the display
  display.display();
*/
  helloWorld();
  // Wait for 10 seconds before clearing the display and drawing "Hello World" again
  delay(10000);
}