#include <forms.h>
#include <X11/Xft/Xft.h>


typedef struct {
    FL_FORM   * f1;
    FL_OBJECT * canvas;
    FL_OBJECT * quit;
} FD_f1;


/***************************************
 * Function called when there's an Expose event for the canvas
 ***************************************/

static int
draw( FL_OBJECT * obj         FL_UNUSED_ARG,
      Window      win,
      int         win_width,
      int         win_height,
      XEvent    * xev         FL_UNUSED_ARG,
      void      * user_data   FL_UNUSED_ARG )
{
    const char * text = "This uses Xft";
    XGlyphInfo extents;
    XftFont * font;
    XftDraw * xftdraw;
    XRenderColor xrcolor;
    XftColor xftcolor;
    Display * display = fl_display;
    int screen        = fl_screen;
    Visual * visual   = fl_state[ fl_vmode ].xvinfo->visual;
    Colormap colormap = fl_state[ fl_vmode ].colormap;

    /* Try to get the exact same font as XForms uses (the inactive section
       should be equivalent) */

#if 1
    font = XftFontOpenXlfd( display, screen,
                            "-*-helvetica-medium-o-*-*-*-240-*-*-p-*-*-*" );
#else
    font = XftFontOpen ( display, screen,
                         XFT_FAMILY, XftTypeString, "helvetica",
                         XFT_SIZE, XftTypeDouble, 24.0,
                         XFT_SLANT, XftTypeInteger, XFT_SLANT_OBLIQUE,
                         NULL );
#endif

    /* Get structure with information needed for rendering with either XRender
       or the X11 core protocol */

    xftdraw = XftDrawCreate( display, win, visual, colormap );

    /* Prepare color (white) for drawing the background */

    xrcolor.red   = 0xffff;
    xrcolor.green = 0xffff;
    xrcolor.blue  = 0xffff;
    xrcolor.alpha = 0xffff;

    XftColorAllocValue( display, visual, colormap, &xrcolor, &xftcolor );

    /* Draw the background (could also done with X11 XDrawRectangle())
       and afterwards release the color used */

    XftDrawRect( xftdraw, &xftcolor, 0, 0, win_width, win_height );
    XftColorFree( display, visual, colormap, &xftcolor );

    /* Prepare color (black) for drawing the string */

    xrcolor.red   = 0x0;
    xrcolor.green = 0x0;
    xrcolor.blue  = 0x0;
    xrcolor.alpha = 0xffff;

    XftColorAllocValue( display, visual, colormap, &xrcolor, &xftcolor );

    /* Get the size of the text to be drawn (for centering) */

    XftTextExtents8( display, font, ( XftChar8 const * ) text, strlen( text ),
                     &extents );

    /* Draw the text */

    XftDrawString8( xftdraw, &xftcolor, font,
                    ( win_width - extents.width ) / 2,
                    ( win_height + extents.height ) / 2,
                    ( XftChar8 const * ) text, strlen( text ) );

    /* Free all allocated resources */

    XftColorFree( display, visual, colormap, &xftcolor );
    XftDrawDestroy( xftdraw );
    XftFontClose( display, font );

    return 1;
}


/***************************************
 ***************************************/

FD_f1 *
create_form_f1( void )
{
    FL_OBJECT *obj;
    FD_f1 *fdui = fl_malloc( sizeof *fdui );

    fdui->f1 = fl_bgn_form( FL_NO_BOX, 280, 180 );

    fl_add_box( FL_FLAT_BOX, 0, 0, 280, 180, "" );

    obj = fl_add_text( FL_NORMAL_TEXT, 20, 20, 240, 40, "This uses X11" );
    fl_set_object_lalign( obj, FL_ALIGN_CENTER );
    fl_set_object_boxtype( obj, FL_DOWN_BOX );
    fl_set_object_lsize( obj, FL_HUGE_SIZE );
    fl_set_object_lstyle( obj, FL_ITALIC_STYLE );
    fl_set_object_color( obj, FL_WHITE, FL_WHITE );

    obj = fdui->canvas = fl_add_canvas( FL_NORMAL_CANVAS, 20, 70, 240, 40, "" );
    fl_add_canvas_handler( obj, Expose, draw, NULL );

    fdui->quit = fl_add_button( FL_NORMAL_BUTTON, 90, 130, 100, 30, "Exit" );

    fl_end_form( );

    return fdui->f1->fdui = fdui;
}


/***************************************
 ***************************************/

int
main( int    argc,
      char * argv[ ] )
{
    FD_f1 *fd_f1;

    fl_initialize( &argc, argv, 0, 0, 0 );
    fd_f1 = create_form_f1( );

    fl_show_form( fd_f1->f1, FL_PLACE_CENTERFREE, FL_FULLBORDER,
                  "X11 versus Xft" );

    while ( fl_do_forms( ) != fd_f1->quit )
        /* empty */ ;

    fl_finish( );
    fl_free( fd_f1 );

    return 0;
}