#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Fonts/FreeMonoBold9pt7b.h>
#include <Fonts/FreeSansBold9pt7b.h>

#define QRCODEVERSION 10
#define SCREEN_WIDTH 400
#define SCREEN_HEIGHT 300
#define BUFFER_SIZE (SCREEN_WIDTH * SCREEN_HEIGHT / 8)
#define CS_PIN 10

GFXcanvas1 display(SCREEN_WIDTH, SCREEN_HEIGHT);

#include "qrencode.h"

void setup() {
    Serial.begin(115200);
    SPI.begin();
    pinMode(CS_PIN, OUTPUT);
    digitalWrite(CS_PIN, HIGH);

    // Clear display
    display.setRotation(3);
    display.fillScreen(0);

    display.setFont(&FreeSansBold9pt7b);
    display.setTextSize(1);
    display.setTextColor(1);

    // Generate QR Code
    String message = "https://antimatter15.com/LOOK_ON_MY_WORKS_YE_MIGHTY_AND_DESPAIR/LOOK_ON_MY_WORKS_YE_MIGHTY_AND_DESPAIRLOOK_ON_MY_WORKS_YE_MIGHTY_AND_DESPAIRLOOK_ON_MY_WORKS_YE_MIGHTY_AND_DESPAIRLOOK_ON_MY_WORKS_YE_MIGHTY_AND_DESPAIR";
    message.toCharArray((char *)strinbuf,456);
    // strncpy((char *)strinbuf, message, 1024);
    qrencode();

    // Calculate QR code position (centered)
    int qr_size = WD; // WD is defined in qrencode.h
    int scale = min(SCREEN_WIDTH, SCREEN_HEIGHT) / qr_size;
    int qr_x = 10; //(SCREEN_HEIGHT - (qr_size * scale)) / 2;
    int qr_y = 10; //(SCREEN_WIDTH - (qr_size * scale)) / 2;

    // Draw QR Code
    for (int y = 0; y < qr_size; y++) {
        for (int x = 0; x < qr_size; x++) {
            if (QRBIT(x,y)) {
                display.fillRect(qr_x + x * scale, qr_y + y * scale, scale, scale, 1);
            }
        }
    }

    // Add text
    // display.setCursor(10, 30);
    // display.println(F("Scan this QR code:"));

    // display.setCursor(10, SCREEN_HEIGHT - 30);
    // display.println(F("https://example.com"));

    // Transmit buffer to the framebuffer chip
    digitalWrite(CS_PIN, LOW);
    SPI.beginTransaction(SPISettings(1000000, MSBFIRST, SPI_MODE0));
    SPI.transfer(display.getBuffer(), BUFFER_SIZE);
    SPI.endTransaction();
    digitalWrite(CS_PIN, HIGH);

    Serial.println("Display updated");
}

void loop() {
    // Nothing to do in the loop for this demo
}