/* Requires the directfb-devel package, compile with
 * gcc -I/usr/include/direcfb -o dfbtest dfbtest.c -ldirectfb
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>

#include <directfb.h>

#define DFBCHECK(x...) \
        {                                                                      \
           int ret = x;                                                        \
           if (ret != DFB_OK) {                                                \
              fprintf( stderr, "%s <%d>:\n\t", __FILE__, __LINE__ );           \
              DirectFBErrorFatal( #x, ret );                                   \
           }                                                                   \
        }

int
main(int argc, char **argv)
{
    IDirectFB *dfb;
    IDirectFBDisplayLayer *dl;
    DFBWindowDescription wdesc;
    IDirectFBScreen *scr;
    IDirectFBWindow *window;
    IDirectFBSurface *surf;
    int screen_width, screen_height;

    // Create the frame buffer interface
    DFBCHECK(DirectFBInit(&argc, &argv))
    DFBCHECK(DirectFBCreate(&dfb));
    DFBCHECK(dfb->SetCooperativeLevel(dfb, DFSCL_EXCLUSIVE));

    // Grab the interface to the screen primary display layer
    DFBCHECK(dfb->GetDisplayLayer(dfb, DLID_PRIMARY, &dl));
    DFBCHECK(dl->SetCooperativeLevel(dl, DLSCL_EXCLUSIVE));
    DFBCHECK(dfb->GetScreen(dfb, 0, &scr));
    DFBCHECK(scr->GetSize(scr, &screen_width, &screen_height));
    DFBCHECK(dl->SetBackgroundColor(dl, 0, 0xff, 0, 0xff));
    DFBCHECK(dl->SetBackgroundMode(dl, DLBM_COLOR));

    /* Create a window */
    memset(&wdesc, 0, sizeof(wdesc));
    wdesc.flags = DWDESC_CAPS | DWDESC_WIDTH | DWDESC_HEIGHT | DWDESC_POSX | DWDESC_POSY | DWDESC_PIXELFORMAT | DWDESC_SURFACE_CAPS | DWDESC_OPTIONS | DWDESC_STACKING;
    wdesc.caps = DWCAPS_DOUBLEBUFFER | DWCAPS_NODECORATION | DWCAPS_NOFOCUS;
    wdesc.width = 100;
    wdesc.height = 100;
    wdesc.posx = screen_width / 2 - 50;
    wdesc.posy = screen_height / 2 - 50;
    wdesc.surface_caps = DSCAPS_FLIPPING;
    wdesc.pixelformat = DSPF_RGB32;
    wdesc.options = DWOP_SCALE | DWOP_INDESTRUCTIBLE | DWOP_GHOST;
    wdesc.stacking = DWSC_UPPER;
    DFBCHECK(dl->CreateWindow(dl, &wdesc, &window))

    window->SetOpacity(window, 0xff);
    window->GetSurface(window, &surf);
    surf->Clear(surf, 0xff, 0xff, 0xff, 0xff);
    surf->Flip(surf, NULL, DSFLIP_ONSYNC);
    window->SetOpacity(window, 0xff);

    sleep(10);

    surf->Release(surf);
    window->Destroy(window);
    window->Release(window);
    dl->Release(dl);
    dfb->Release (dfb);

    return 0;
}