/**************************************
*
* Copyright 2008 by Sean Conner.  All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*
* Comments, questions and criticisms can be sent to: sean@conman.org
*
**************************************/

#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <assert.h>

#include <getopt.h>

#include <X11/Xlib.h>
#include <X11/Xatom.h>

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

extern char *optarg;
extern int   optind;
extern int   opterr;
extern int   optopt;

Display *gdisplay;
Window   gwindow;
int      gdebug;

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

static void cleanup(void)
{
  if (gwindow) XDestroyWindow(gdisplay,gwindow);
  if (gdisplay) XCloseDisplay(gdisplay);
}

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

static void *get_data(
			unsigned long *pitems,
			int           *pformat,
			Atom           selection,
			Atom           target,
			Atom           property
		     )
{
  XEvent         event;
  Atom           type;
  unsigned long  bytes;
  unsigned char *data;
  int            rc;
  
  *pitems = 0;
  
  XConvertSelection(
  	gdisplay,
  	selection,
  	target,
  	property,
  	gwindow,
  	CurrentTime
  );
  
  do
    XNextEvent(gdisplay,&event);
  while (event.type != SelectionNotify);
  
  if (event.xselection.property == None)
    return(NULL);
  
  rc = XGetWindowProperty(
  		event.xselection.display,
  		event.xselection.requestor,
  		event.xselection.property,
  		0,
  		LONG_MAX / 4,
  		True,
  		AnyPropertyType,
  		&type,
  		pformat,
  		pitems,
  		&bytes,
  		&data
  	);
  
  if (rc == 1) return(NULL);
  
  if (gdebug)
  {
    char *text;
    
    text = XGetAtomName(gdisplay,type);
    fprintf(
    	stderr,
    	"Type returned: %s\n"
    	"Format:        %d\n"
    	"Number items:  %lu\n",
    	text,
    	*pformat,
    	*pitems
    );
    XFree(text);
  }
  
  return((void *)data);  
}

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

static void do_selection(Atom selection,Atom target,Atom property)
{
  unsigned long items;
  unsigned long i;
  char          *data;
  int            format;
  
  data = get_data(&items,&format,selection,target,property);
  if (data == NULL) return;
  switch(format)
  {
    case 32: items *= 4; break;
    case 16: items *= 2; break;
    case  8:             break;
    default: assert(0);  break;
  }
  fwrite(data,1,items,stdout);
}

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

int main(int argc,char *argv[])
{
  Atom  selection;
  Atom  target;
  Atom  property;
  char *name;
  int   ftarget = 0;
  int   c;
  
  atexit(cleanup);
  
  gdisplay = XOpenDisplay(NULL);
  if (gdisplay == NULL)
  {
    fprintf(stderr,"failed to open display\n");
    return EXIT_FAILURE;
  }
  
  selection = XA_PRIMARY;
  target    = XA_STRING;
  property  = XInternAtom(gdisplay,"XSELECT",False);
  
  while((c = getopt(argc,argv,"pswcqdh")) != -1)
  {
    switch(c)
    {
      case 'd': gdebug       = 1; break;
      case 'p': selection    = XA_PRIMARY; break;
      case 's': selection    = XA_SECONDARY; break;
      case 'c': selection    = XInternAtom(gdisplay,"CLIPBOARD",False); break;
      case 'q': target       = XInternAtom(gdisplay,"TARGETS",False); ftarget = 1; break;
      case 'h':
      default:
           fprintf(
           	stderr,
           	"usage: %s [-d] [-h] [-w] [-p] [-s] [-c] [-q] [<target> ... ]\n"
           	"\t-d\tdebug information\n"
           	"\t-h\thelp\n"
           	"\t-p\tselect primary (default)\n"
           	"\t-s\tselect secondary\n"
           	"\t-c\tselect clipboard\n"
           	"\t-w\tcreate hidden window\n"
           	"\t-q\tquery selection for targets\n"
           	"\t<target>\tselection type\n",
           	argv[0]
           );
           
           return EXIT_FAILURE;
    }
  }
  
  gwindow = XCreateSimpleWindow(
  		gdisplay,
  		RootWindow(gdisplay,DefaultScreen(gdisplay)),
  		0,
  		0,
  		10,
  		10,
  		1,
  		0,
  		0
  	);
  if (ftarget)
  {
    unsigned long  items;
    unsigned long  i;
    Atom          *list;
    int            format;
    
    list = get_data(&items,&format,selection,target,property);
    
    if (list == NULL)
    {
      fprintf(stderr,"current selection doesn't support querying\n");
      return EXIT_FAILURE;
    }
    
    for (i = 0 ; i < items ; i++)
    {
      name = XGetAtomName(gdisplay,list[i]);
      printf("%s\n",name);
      XFree(name);
    }
    
    XFree(list);
    return EXIT_SUCCESS;
  }
  
  if (optind == argc)
    do_selection(selection,target,property);
  else
    for ( ; optind < argc ; optind++)
    {
      target = XInternAtom(gdisplay,argv[optind],True);
      if (target == None) continue;
      do_selection(selection,target,property);
    }
  
  return EXIT_SUCCESS;
}