#include <lvgl.h>
#include <TFT_eSPI.h>
/*If you want to use the LVGL examples,
  make sure to install the lv_examples Arduino library
  and uncomment the following line.
#include <lv_examples.h>*/

TFT_eSPI tft = TFT_eSPI(); /*TFT instance*/

/*Change to your screen resolution*/
static uint32_t screenWidth = 320;
static uint32_t screenHeight = 240;

static lv_draw_buf_t draw_buf;
static lv_color_t buf[screenWidth * 10];

#if LV_USE_LOG != 0
/*Serial debugging*/
void my_print(lv_log_level_t level, const char *file, uint32_t line, const char *fn_name, const char *dsc)
{
    Serial.printf("%s(%s)@%d->%s\r\n", file, fn_name, line, dsc);
    Serial.flush();
}
#endif

/*Display flushing*/
void my_disp_flush(lv_disp_drv_t *disp, const lv_area_t *area, lv_color_t *color_p)
{
    uint32_t w = (area->x2 - area->x1 + 1);
    uint32_t h = (area->y2 - area->y1 + 1);

    tft.startWrite();
    tft.setAddrWindow(area->x1, area->y1, w, h);
    tft.pushColors(&color_p->full, w * h, true);
    tft.endWrite();

    lv_disp_flush_ready(disp);
}

/*Read the touchpad*/
bool my_touchpad_read(lv_indev_drv_t *indev_driver, lv_indev_data_t *data)
{
    uint16_t touchX, touchY;

    bool touched = tft.getTouch(&touchX, &touchY, 600);

    if(!touched) {
      data->state = LV_INDEV_STATE_REL;
    } else {
      data->state = LV_INDEV_STATE_PR;
	    
      /*Set the coordinates*/
      data->point.x = touchX;
      data->point.y = touchY;
  
      Serial.print("Data x");
      Serial.println(touchX);
      
      Serial.print("Data y");
      Serial.println(touchY);
    }

    return false; /*Return `false` because we are not buffering and no more data to read*/
}

void setup()
{
    Serial.begin(115200); /*prepare for possible serial debug*/

    lv_init();

#if LV_USE_LOG != 0
    lv_log_register_print_cb(my_print); /*register print function for debugging*/
#endif

    tft.begin();        /*TFT init*/
    tft.setRotation(1); /*Landscape orientation*/

    /*Set the touchscreen calibration data,
      the actual data for your display can be aquired using
      the Generic -> Touch_calibrate example from the TFT_eSPI library*/
    uint16_t calData[5] = {275, 3620, 264, 3532, 1};
    tft.setTouch(calData);

    lv_draw_buf_init(&draw_buf, buf, NULL, screenWidth * 10);

    /*Initialize the display*/
    lv_disp_drv_t disp_drv;
    lv_disp_drv_init(&disp_drv);
    /*Change the following line to your display resolution*/
    disp_drv.hor_res = screenWidth;
    disp_drv.ver_res = screenHeight;
    disp_drv.flush_cb = my_disp_flush;
    disp_drv.draw_buf = &draw_buf;
    lv_disp_drv_register(&disp_drv);

    /*Initialize the (dummy) input device driver*/
    lv_indev_drv_t indev_drv;
    lv_indev_drv_init(&indev_drv);
    indev_drv.type = LV_INDEV_TYPE_POINTER;
    indev_drv.read_cb = my_touchpad_read;
    lv_indev_drv_register(&indev_drv);

    /*Try an example from the lv_examples Arduino library
      make sure to include it as written above.
    lv_example_btn_1();*/
}

void loop()
{
    lv_timer_handler(); /*let the GUI do its work*/
    delay(5);
}