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#include "unix/guts.h"
#include "Application.h"
#include "Clipboard.h"
#include "Icon.h"

#define WIN PComponent(application)-> handle

#define CF_NAME(x)   (guts. clipboard_formats[(x)*3])
#define CF_TYPE(x)   (guts. clipboard_formats[(x)*3+1])
#define CF_FORMAT(x) (guts. clipboard_formats[(x)*3+2])
#define CF_ASSIGN(i,a,b,c) CF_NAME(i)=(a);CF_TYPE(i)=(b);CF_FORMAT(i)=((Atom)c)
#define CF_32        (sizeof(long)*8)        /* 32-bit properties are hacky */

Bool
prima_init_clipboard_subsystem(char * error_buf)
{
	guts. clipboards = hash_create();
	
	if ( !(guts. clipboard_formats = malloc( cfCOUNT * 3 * sizeof(Atom)))) {
		sprintf( error_buf, "No memory");
		return false;
	}
	guts. clipboard_formats_count = cfCOUNT;
#if (cfText != 0) || (cfBitmap != 1) || (cfUTF8 != 2)
#error broken clipboard type formats
#endif  

	CF_ASSIGN(cfText, XA_STRING, XA_STRING, 8);
	CF_ASSIGN(cfUTF8, UTF8_STRING, UTF8_STRING, 8);
	CF_ASSIGN(cfBitmap, XA_PIXMAP, XA_PIXMAP, CF_32);
	CF_ASSIGN(cfTargets, CF_TARGETS, XA_ATOM, CF_32);

	/* XXX - bitmaps and indexed pixmaps may have the associated colormap or pixel values 
	CF_ASSIGN(cfPalette, XA_COLORMAP, XA_ATOM, CF_32);
	CF_ASSIGN(cfForeground, CF_FOREGROUND, CF_PIXEL, CF_32);
	CF_ASSIGN(cfBackground, CF_BACKGROUND, CF_PIXEL, CF_32);
	*/
	
	guts. clipboard_event_timeout = 2000;
	return true;
}

PList
apc_get_standard_clipboards( void)
{
	PList l = plist_create( 3, 1);
	if (!l) return nil;
	list_add( l, (Handle)duplicate_string( "Primary"));
	list_add( l, (Handle)duplicate_string( "Secondary"));
	list_add( l, (Handle)duplicate_string( "Clipboard"));
	return l;
}

Bool
apc_clipboard_create( Handle self)
{
	PClipboard c = (PClipboard)self;
	char *name, *x;
	DEFCC;

	XX-> selection = None;
	
	name = x = duplicate_string( c-> name);
	while (*x) {
		*x = toupper(*x);
		x++;
	}
	XX-> selection = XInternAtom( DISP, name, false);
	free( name);

	if ( hash_fetch( guts.clipboards, &XX->selection, sizeof(XX->selection))) {
		warn("This clipboard is already present");
		return false;
	}

	if ( !( XX-> internal = malloc( sizeof( ClipboardDataItem) * cfCOUNT))) {
		warn("Not enough memory");
		return false;
	}
	if ( !( XX-> external = malloc( sizeof( ClipboardDataItem) * cfCOUNT))) {
		free( XX-> internal);
		warn("Not enough memory");
		return false;
	}
	bzero( XX-> internal, sizeof( ClipboardDataItem) * cfCOUNT);
	bzero( XX-> external, sizeof( ClipboardDataItem) * cfCOUNT);

	hash_store( guts.clipboards, &XX->selection, sizeof(XX->selection), (void*)self);

	return true;
}

static void
clipboard_free_data( void * data, int size, Handle id)
{
	if ( size <= 0) {
		if ( size == 0 && data != nil) free( data);
		return;
	}
	if ( id == cfBitmap) {
		int i;
		Pixmap * p = (Pixmap*) data;
		for ( i = 0; i < size/sizeof(Pixmap); i++, p++)
			if ( *p)
				XFreePixmap( DISP, *p);
	}
	free( data);
}

/*
	each clipboard type can be represented by a set of 
	X properties pairs, where each is X name and X type.
	get_typename() returns such pairs by the index.
*/
static Atom
get_typename( Handle id, int index, Atom * type)
{
	if ( type) *type = None;
	switch ( id) {
	case cfUTF8:
		if ( index > 1) return None;
		if ( index == 0) {
			if ( type) *type = CF_TYPE(id);
			return CF_NAME(id);
		} else {
			if ( type) *type = UTF8_MIME;
			return UTF8_MIME;
		}
	case cfBitmap:
		if ( index > 1) return None;
		if ( index == 0) {
			if ( type) *type = CF_TYPE(id);
			return CF_NAME(id);
		} else {
			if ( type) *type = XA_BITMAP;
			return XA_BITMAP;
		}
	case cfTargets:
		if ( index > 1) return None;
		if ( index == 0) {
			if ( type) *type = CF_TYPE(id);
			return CF_NAME(id);
		} else {
			if ( type) *type = CF_TARGETS;
			return CF_NAME(id);
		}
	}
	if ( index > 0) return None;
	if ( type) *type = CF_TYPE(id);
	return CF_NAME(id);
}

static void
clipboard_kill_item( PClipboardDataItem item, Handle id)
{
	item += id;
	clipboard_free_data( item-> data, item-> size, id);
	item-> data = nil;
	item-> size = 0;
	item-> name = get_typename( id, 0, nil);
}

/*
	Deletes a transfer record from pending xfer chain.
*/
static void
delete_xfer( PClipboardSysData cc, ClipboardXfer * xfer)
{
	ClipboardXferKey key;
	CLIPBOARD_XFER_KEY( key, xfer-> requestor, xfer-> property);
	if ( guts. clipboard_xfers) {
		IV refcnt;
		hash_delete( guts. clipboard_xfers, key, sizeof( key), false);
		refcnt = PTR2IV( hash_fetch( guts. clipboard_xfers, &xfer-> requestor, sizeof(XWindow)));
		if ( --refcnt == 0) {
			XSelectInput( DISP, xfer-> requestor, 0);
			hash_delete( guts. clipboard_xfers, &xfer-> requestor, sizeof(XWindow), false);
		} else {
			if ( refcnt < 0) refcnt = 0;
			hash_store( guts. clipboard_xfers, &xfer-> requestor, sizeof(XWindow), INT2PTR(void*, refcnt));
		}
	}
	if ( cc-> xfers) 
		list_delete( cc-> xfers, ( Handle) xfer);
	if ( xfer-> data_detached && xfer-> data_master) 
		clipboard_free_data( xfer-> data, xfer-> size, xfer-> id);
	free( xfer);
}

Bool
apc_clipboard_destroy( Handle self)
{
	DEFCC;
	int i;

	if (XX-> selection == None) return true;

	if ( XX-> xfers) {
		for ( i = 0; i < XX-> xfers-> count; i++) 
			delete_xfer( XX, ( ClipboardXfer*) XX-> xfers-> items[i]);
		plist_destroy( XX-> xfers);
	}

	for ( i = 0; i < guts. clipboard_formats_count; i++) {
		if ( XX-> external) clipboard_kill_item( XX-> external, i);
		if ( XX-> internal) clipboard_kill_item( XX-> internal, i);
	}

	free( XX-> external);
	free( XX-> internal);
	hash_delete( guts.clipboards, &XX->selection, sizeof(XX->selection), false);

	XX-> selection = None;
	return true;
}

Bool
apc_clipboard_open( Handle self)
{
	DEFCC;
	if ( XX-> opened) return false;
	XX-> opened = true;
	
	if ( !XX-> inside_event) XX-> need_write = false;

	return true;
}

Bool
apc_clipboard_close( Handle self)
{
	DEFCC;
	if ( !XX-> opened) return false;
	XX-> opened = false;

	/* check if UTF8 is present and Text is not, and downgrade */
	if ( XX-> need_write &&
		XX-> internal[cfUTF8]. size > 0 &&
		XX-> internal[cfText]. size == 0) {
		Byte * src = XX-> internal[cfUTF8]. data;
		int len    = utf8_length( src, src + XX-> internal[cfUTF8]. size);
		if (( XX-> internal[cfText]. data = malloc( len))) {
			STRLEN charlen;
			U8 *dst;
			dst = XX-> internal[cfText]. data;
			XX-> internal[cfText]. size = len;
			while ( len--) {
				register UV u = 
#if PERL_PATCHLEVEL >= 16
				utf8_to_uvchr_buf( src, src + XX-> internal[cfUTF8]. size, &charlen);
#else
				utf8_to_uvchr( src, &charlen)
#endif
				;
				*(dst++) = ( u < 0x7f) ? u : '?'; /* XXX employ $LANG and iconv() */
				src += charlen;
			}
		} 
	}
		

	if ( !XX-> inside_event) {
		int i;         
		for ( i = 0; i < guts. clipboard_formats_count; i++) 
			clipboard_kill_item( XX-> external, i);
		if ( XX-> need_write) 
			if ( XGetSelectionOwner( DISP, XX-> selection) != WIN) 
				XSetSelectionOwner( DISP, XX-> selection, WIN, CurrentTime);
	}
	
	return true;
}

/*
	Detaches data for pending transfers from XX, so eventual changes 
	to XX->internal would not affect them. detach_xfers() should be
	called before clipboard_kill_item(XX-> internal), otherwise
	there's a chance of coredump.
*/
static void
detach_xfers( PClipboardSysData XX, Handle id, Bool clear_original_data)
{
	int i, got_master = 0, got_anything = 0;
	if ( !XX-> xfers) return;
	for ( i = 0; i < XX-> xfers-> count; i++) {
		ClipboardXfer * x = ( ClipboardXfer *) XX-> xfers-> items[i];
		if ( x-> data_detached || x-> id != id) continue;
		got_anything = 1;
		if ( !got_master) {
			x-> data_master = true;
			got_master = 1;
		}
		x-> data_detached = true;
	}   
	if ( got_anything && clear_original_data) {
		XX-> internal[id]. data = nil;
		XX-> internal[id]. size = 0;
		XX-> internal[id]. name = get_typename( id, 0, nil);
	}
}

Bool
apc_clipboard_clear( Handle self)
{
	DEFCC;
	int i;

	for ( i = 0; i < guts. clipboard_formats_count; i++) {
		detach_xfers( XX, i, true);
		clipboard_kill_item( XX-> internal, i);
		clipboard_kill_item( XX-> external, i);
	}
	
	if ( XX-> inside_event) { 
		XX-> need_write = true; 
	} else {
		XWindow owner = XGetSelectionOwner( DISP, XX-> selection);
		XX-> need_write = false;
		if ( owner != None && owner != WIN)
			XSetSelectionOwner( DISP, XX-> selection, None, CurrentTime);
	}

	return true;
}

typedef struct {
	Atom selection;
	long mask;
} SelectionProcData;

#define SELECTION_NOTIFY_MASK 1
#define PROPERTY_NOTIFY_MASK  2

static int
selection_filter( Display * disp, XEvent * ev, SelectionProcData * data)
{
	switch ( ev-> type) {
	case PropertyNotify:
		return (data-> mask & PROPERTY_NOTIFY_MASK) && (data-> selection == ev-> xproperty. atom);
	case SelectionRequest:
	case SelectionClear:
	case MappingNotify:
		return true;
	case SelectionNotify:
		return (data-> mask & SELECTION_NOTIFY_MASK) && (data-> selection == ev-> xselection. selection);
	case ClientMessage:
		if ( ev-> xclient. window == WIN ||
			ev-> xclient. window == guts. root ||
			ev-> xclient. window == None) return true;
		if ( hash_fetch( guts.windows, (void*)&ev-> xclient. window, 
			sizeof(ev-> xclient. window))) return false;
		return true;
	}
	return false;
}

#define CFDATA_NONE            0
#define CFDATA_NOT_ACQUIRED  (-1)
#define CFDATA_ERROR         (-2)

#define RPS_OK       0
#define RPS_PARTIAL  1
#define RPS_NODATA   2
#define RPS_ERROR    3

static int
read_property( Atom property, Atom * type, int * format, 
					unsigned long * size, unsigned char ** data)
{
	int ret = ( *size > 0) ? RPS_PARTIAL : RPS_ERROR;
	unsigned char * prop, *a1;
	unsigned long n, left, offs = 0, new_size, big_offs = *size;

	XCHECKPOINT;
	Cdebug("clipboard: read_property: %s\n", XGetAtomName(DISP, property));
	while ( 1) {
		if ( XGetWindowProperty( DISP, WIN, property,
			offs, guts. limits. request_length - 4, false, 
			AnyPropertyType, 
			type, format, &n, &left, &prop) != Success) {
			XDeleteProperty( DISP, WIN, property);
			Cdebug("clipboard:fail\n");
			return ret;
		}
		XCHECKPOINT;
		Cdebug("clipboard: type=0x%x(%s) fmt=%d n=%d left=%d\n", 
				*type, XGetAtomName(DISP,*type), *format, n, left);
		
		if ( *format == 32) *format = CF_32;

		if ( *type == 0 ) return RPS_NODATA;

		new_size = n * *format / 8;

		if ( new_size > 0) {
			if ( !( a1 = realloc( *data, big_offs + offs * 4 + new_size))) {
				warn("Not enough memory: %ld bytes\n", offs * 4 + new_size);
				XDeleteProperty( DISP, WIN, property);
				XFree( prop);
				return ret;
			}
			*data = a1;
			memcpy( *data + big_offs + offs * 4, prop, new_size);
			*size = big_offs + (offs * 4) + new_size;
			if ( *size > INT_MAX) *size = INT_MAX;
			offs += new_size / 4;
			ret = RPS_PARTIAL;
		}
		XFree( prop);
		if ( left <= 0 || *size == INT_MAX || n * *format == 0) break;
	}

	XDeleteProperty( DISP, WIN, property);
	XCHECKPOINT;

	return RPS_OK;
}

static Bool
query_datum( Handle self, Handle id, Atom query_target, Atom query_type)
{
	DEFCC;
	XEvent ev;
	Atom type;
	int format, rps;
	SelectionProcData spd;
	unsigned long size = 0, incr = 0, old_size, delay;
	unsigned char * data;
	struct timeval start_time, timeout;

	/* init */
	if ( query_target == None) return false;
	data = malloc(0);
	XX-> external[id]. size = CFDATA_ERROR;
	gettimeofday( &start_time, nil);
	XCHECKPOINT;
	Cdebug("clipboard:convert %s from %08x\n", XGetAtomName( DISP, query_target), WIN);
	XDeleteProperty( DISP, WIN, XX-> selection);
	XConvertSelection( DISP, XX-> selection, query_target, XX-> selection, WIN, guts. last_time);
	XFlush( DISP);
	XCHECKPOINT;

	/* wait for SelectionNotify */
	spd. selection = XX-> selection;
	spd. mask = SELECTION_NOTIFY_MASK;
	while ( 1) {
		XIfEvent( DISP, &ev, (XIfEventProcType)selection_filter, (char*)&spd);
		if ( ev. type != SelectionNotify) {
			prima_handle_event( &ev, nil);
			continue;
		}
		if ( ev. xselection. property == None) goto FAIL;
		Cdebug("clipboard:read SelectionNotify  %s %s\n",
				XGetAtomName(DISP, ev. xselection. property),
				XGetAtomName(DISP, ev. xselection. target));
		gettimeofday( &timeout, nil);
		delay = 2 * (( timeout. tv_sec - start_time. tv_sec) * 1000 + 
						( timeout. tv_usec - start_time. tv_usec) / 1000) + guts. clipboard_event_timeout;
		start_time = timeout;
		if ( read_property( ev. xselection. property, &type, &format, &size, &data) > RPS_PARTIAL) 
			goto FAIL;
		XFlush( DISP);
		break;
	}
	XCHECKPOINT;

	if ( type != XA_INCR) { /* ordinary, single-property selection */
		if ( format != CF_FORMAT(id) || type != query_type) {
			if ( format != CF_FORMAT(id)) 
				Cdebug("clipboard: id=%d: formats mismatch: got %d, want %d\n", id, format, CF_FORMAT(id));
			if ( type != query_type) 
				Cdebug("clipboard: id=%d: types mismatch: got %s, want %s\n", id,
						XGetAtomName(DISP,type), XGetAtomName(DISP,query_type));
			return false;
		}
		XX-> external[id]. size = size;
		XX-> external[id]. data = data;
		XX-> external[id]. name = query_target;
		return true;
	}

	/* setup INCR */
	if ( format != CF_32 || size < 4) goto FAIL;
	incr = (unsigned long) *(( Atom*) data);
	if ( incr == 0) goto FAIL;
	size = 0;
	spd. mask = PROPERTY_NOTIFY_MASK;

	while ( 1) {
		/* wait for PropertyNotify */ 
		while ( XCheckIfEvent( DISP, &ev, (XIfEventProcType)selection_filter, (char*)&spd) == False) {
			gettimeofday( &timeout, nil);
			if ((( timeout. tv_sec - start_time. tv_sec) * 1000 + 
				( timeout. tv_usec - start_time. tv_usec) / 1000) > delay) 
				goto END_LOOP;
		}
		if ( ev. type != PropertyNotify) {
			prima_handle_event( &ev, nil);
			continue;
		}
		if ( ev. xproperty. state != PropertyNewValue) continue;
		start_time = timeout;
		old_size = size;

		rps = read_property( ev. xproperty. atom, &type, &format, &size, &data);
		XFlush( DISP);
		if ( rps == RPS_NODATA) continue;
		if ( rps == RPS_ERROR) goto FAIL;         
		if ( format != CF_FORMAT(id) || type != CF_TYPE(id)) return false;
		if ( size > incr ||                       /* read all in INCR */
			rps == RPS_PARTIAL ||                /* failed somewhere */
			( size == incr && old_size == size)  /* wait for empty PropertyNotify otherwise */
			) break;
	}
END_LOOP:
	XCHECKPOINT;

	XX-> external[id]. size   = size;
	XX-> external[id]. data   = data;
	XX-> external[id]. name   = query_target;
	return true;
	
FAIL:
	XCHECKPOINT;
	free( data);
	return false;
}


static Bool
query_data( Handle self, Handle id)
{
	Atom name, type;
	int index = 0;
	while (( name = get_typename( id, index++, &type)) != None) {
		if ( query_datum( self, id, name, type)) return true;
	}
	return false;
}

static Atom
find_atoms( Atom * data, int length, int id)
{
	int i, index = 0;
	Atom name;
	
	while (( name = get_typename( id, index++, nil)) != None) {
		for ( i = 0; i < length / sizeof(Atom); i++) {
			if ( data[i] == name) 
				return name;
		}
	}
	return None;
}


Bool
apc_clipboard_has_format( Handle self, Handle id)
{
	DEFCC;
	if ( id >= guts. clipboard_formats_count) return false;

	if ( XX-> inside_event) {
		return XX-> internal[id]. size > 0 || XX-> external[id]. size > 0;
	} else {
		if ( XX-> internal[id]. size > 0) return true;

		if ( XX-> external[cfTargets]. size == 0) {
			/* read TARGETS, which as array of ATOMs */
			query_data( self, cfTargets);

			if ( XX-> external[cfTargets].size > 0) {
				int i, size = XX-> external[cfTargets].size;
				Atom * data = ( Atom*)(XX-> external[cfTargets]. data);
				Atom ret;

				
				Cdebug("clipboard targets:");
				for ( i = 0; i < size/4; i++) 
					Cdebug("%s\n", XGetAtomName( DISP, data[i]));

				/* find our index for TARGETS[i], assign CFDATA_NOT_ACQUIRED to it */
				for ( i = 0; i < guts. clipboard_formats_count; i++) {
					if ( i == cfTargets) continue;
					ret = find_atoms( data, size, i);
					if ( ret != None && (
							XX-> external[i]. size == 0 ||
							XX-> external[i]. size == CFDATA_ERROR
						)
						) { 
						XX-> external[i]. size = CFDATA_NOT_ACQUIRED;
						XX-> external[i]. name = ret;
					}
				}

				if ( XX-> external[id]. size == 0 || 
					XX-> external[id]. size == CFDATA_ERROR)
					return false;
			}
		}
		
		if ( XX-> external[id]. size > 0 || 
			XX-> external[id]. size == CFDATA_NOT_ACQUIRED)
			return true;

		if ( XX-> external[id]. size == CFDATA_ERROR) 
			return false;

		/* selection owner does not support TARGETS, so peek */
		if ( XX-> external[cfTargets]. size == 0 && XX-> internal[id]. size == 0)
			return query_data( self, id);
	}
	return false;
}

Bool
apc_clipboard_get_data( Handle self, Handle id, PClipboardDataRec c)
{
	DEFCC;
	STRLEN size;
	unsigned char * data;
	Atom name;

	if ( id >= guts. clipboard_formats_count) return false;

	if ( !XX-> inside_event) {
		if ( XX-> internal[id]. size == 0) {
			if ( XX-> external[id]. size == CFDATA_NOT_ACQUIRED) {
				if ( !query_data( self, id)) return false;
			}
			if ( XX-> external[id]. size == CFDATA_ERROR) return false;
		}
	}
	if ( XX-> internal[id]. size == CFDATA_ERROR) return false;

	if ( XX-> internal[id]. size > 0) {
		size = XX-> internal[id]. size;
		data = XX-> internal[id]. data;
		name = XX-> internal[id]. name;
	} else {
		size = XX-> external[id]. size;
		data = XX-> external[id]. data;
		name = XX-> external[id]. name;
	}
	if ( size == 0 || data == nil) return false;

	switch ( id) {
	case cfBitmap: {
		Handle img = c-> image; 
		XWindow foo;
		Pixmap px = *(( Pixmap*)( data));
		unsigned int dummy, x, y, d;
		int bar;
	
		if ( !XGetGeometry( DISP, px, &foo, &bar, &bar, &x, &y, &dummy, &d))
			return false;
		CImage( img)-> create_empty( img, x, y, ( d == 1) ? imBW : guts. qdepth);
		if ( !prima_std_query_image( img, px)) return false;
		break;}
	case cfText:
	case cfUTF8: {
		void * ret = malloc( size);
		if ( !ret) {
			warn("Not enough memory: %d bytes\n", (int)size);
			return false;
		}
		memcpy( ret, data, size);
		c-> data   = ret;
		c-> length = size;
		break;}
	default: {
		void * ret = malloc( size);
		if ( !ret) {
			warn("Not enough memory: %d bytes\n", (int)size);
			return false;
		}
		memcpy( ret, data, size);
		c-> data = ( Byte * ) ret;
		c-> length = size;
		break;}
	}
	return true;
}

Bool
apc_clipboard_set_data( Handle self, Handle id, PClipboardDataRec c)
{
	DEFCC;
	if ( id >= guts. clipboard_formats_count) return false;

	if ( id >= cfTargets && id < cfCOUNT ) return false;
	detach_xfers( XX, id, true);
	clipboard_kill_item( XX-> internal, id);

	switch ( id) {
	case cfBitmap: {  
		Pixmap px = prima_std_pixmap( c-> image, CACHE_LOW_RES);
		if ( px) {
			if ( !( XX-> internal[cfBitmap]. data = malloc( sizeof( px)))) {
				XFreePixmap( DISP, px);
				return false;
			}
			XX-> internal[cfBitmap]. size = sizeof(px);
			memcpy( XX-> internal[cfBitmap]. data, &px, sizeof(px));
		} else
			return false;
		break;}
	default:
		if ( !( XX-> internal[id]. data = malloc( c-> length))) 
			return false;
		XX-> internal[id]. size = c-> length;
		memcpy( XX-> internal[id]. data, c-> data, c-> length);
		break;
	}
	XX-> need_write = true; 
	return true;
}

static Bool
expand_clipboards( Handle self, int keyLen, void * key, void * dummy)
{
	DEFCC;
	PClipboardDataItem f;

	if ( !( f = realloc( XX-> internal, 
		sizeof( ClipboardDataItem) * guts. clipboard_formats_count))) {
		guts. clipboard_formats_count--;
		return true;
	}
	f[ guts. clipboard_formats_count-1].size = 0;
	f[ guts. clipboard_formats_count-1].data = nil;
	f[ guts. clipboard_formats_count-1].name = CF_NAME(guts. clipboard_formats_count-1);
	XX-> internal = f;
	if ( !( f = realloc( XX-> external, 
		sizeof( ClipboardDataItem) * guts. clipboard_formats_count))) {
		guts. clipboard_formats_count--;
		return true;
	}
	f[ guts. clipboard_formats_count-1].size = 0;
	f[ guts. clipboard_formats_count-1].data = nil;
	f[ guts. clipboard_formats_count-1].name = CF_NAME(guts. clipboard_formats_count-1);
	XX-> external = f;
	return false;
}

Handle
apc_clipboard_register_format( Handle self, const char* format)
{
	int i;
	Atom x = XInternAtom( DISP, format, false);
	Atom *f;

	for ( i = 0; i < guts. clipboard_formats_count; i++) {
		if ( x == CF_NAME(i)) 
			return i;
	}

	if ( !( f = realloc( guts. clipboard_formats, 
		sizeof( Atom) * 3 * ( guts. clipboard_formats_count + 1)))) 
		return false;
	
	guts. clipboard_formats = f;
	CF_ASSIGN( guts. clipboard_formats_count, x, x, 8); 
	guts. clipboard_formats_count++;

	if ( hash_first_that( guts. clipboards, (void*)expand_clipboards, nil, nil, nil))
		return -1;

	return guts. clipboard_formats_count - 1;
}

Bool
apc_clipboard_deregister_format( Handle self, Handle id)
{
	return true;
}

ApiHandle
apc_clipboard_get_handle( Handle self)
{
	return C(self)-> selection;
}

static Bool
delete_xfers( Handle self, int keyLen, void * key, XWindow * window)
{
	DEFCC;
	if ( XX-> xfers) {
		int i;
		for ( i = 0; i < XX-> xfers-> count; i++) 
			delete_xfer( XX, ( ClipboardXfer*) XX-> xfers-> items[i]);     
	}
	hash_delete( guts. clipboard_xfers, window, sizeof( XWindow), false);
	return false; 
}

void
prima_handle_selection_event( XEvent *ev, XWindow win, Handle self)
{
	XCHECKPOINT;
	switch ( ev-> type) {
	case SelectionRequest: {
		XEvent xe;
		int i, id = -1;
		Atom prop   = ev-> xselectionrequest. property,
			target = ev-> xselectionrequest. target;
		self = ( Handle) hash_fetch( guts. clipboards, &ev-> xselectionrequest. selection, sizeof( Atom)); 

		guts. last_time = ev-> xselectionrequest. time;
		xe. type      = SelectionNotify;
		xe. xselection. send_event = true;
		xe. xselection. serial    = ev-> xselectionrequest. serial;
		xe. xselection. display   = ev-> xselectionrequest. display;
		xe. xselection. requestor = ev-> xselectionrequest. requestor;
		xe. xselection. selection = ev-> xselectionrequest. selection;
		xe. xselection. target    = target;
		xe. xselection. property  = None;
		xe. xselection. time      = ev-> xselectionrequest. time;
		
		Cdebug("from %08x %s at %s\n", ev-> xselectionrequest. requestor, 
			XGetAtomName( DISP, ev-> xselectionrequest. target),
			XGetAtomName( DISP, ev-> xselectionrequest. property)
		);

		if ( self) { 
			PClipboardSysData CC = C(self);
			Bool event = CC-> inside_event;
			int format, utf8_mime = 0;

			for ( i = 0; i < guts. clipboard_formats_count; i++) {
				if ( xe. xselection. target == CC-> internal[i]. name) {
					id = i;
					break;
				} else if ( i == cfUTF8 && xe. xselection. target == UTF8_MIME) {
					id = i;
					utf8_mime = 1;
					break;
				}
			}
			if ( id < 0) goto SEND_EMPTY;
			for ( i = 0; i < guts. clipboard_formats_count; i++)
				clipboard_kill_item( CC-> external, i);
			
			CC-> target = xe. xselection. target;
			CC-> need_write = false;
			
			CC-> inside_event = true;
			/* XXX cmSelection */
			CC-> inside_event = event;

			format = CF_FORMAT(id);
			target = CF_TYPE( id);
			if ( utf8_mime) target = UTF8_MIME;

			if ( id == cfTargets) { 
				int count = 0, have_utf8 = 0;
				Atom * ci;
				for ( i = 0; i < guts. clipboard_formats_count; i++) {
					if ( i != cfTargets && CC-> internal[i]. size > 0) {
						count++;
						if ( i == cfUTF8) {
							count++;
							have_utf8 = 1;
						}
					}
				}
				detach_xfers( CC, cfTargets, true);
				clipboard_kill_item( CC-> internal, cfTargets);
				if (( CC-> internal[cfTargets]. data = malloc( count * sizeof( Atom)))) {
					CC-> internal[cfTargets]. size = count * sizeof( Atom);
					ci = (Atom*)CC-> internal[cfTargets]. data;
					for ( i = 0; i < guts. clipboard_formats_count; i++) 
						if ( i != cfTargets && CC-> internal[i]. size > 0) 
							*(ci++) = CF_NAME(i);
					if ( have_utf8) 
						*(ci++) = UTF8_MIME;
				}
			}
		
			if ( CC-> internal[id]. size > 0) {
				Atom incr;
				int mode = PropModeReplace;
				unsigned char * data = CC-> internal[id]. data;
				unsigned long size = CC-> internal[id]. size * 8 / format;
				if ( CC-> internal[id]. size > guts. limits. request_length - 4) {
					int ok = 0;
					int reqlen = guts. limits. request_length - 4;
					/* INCR */
					if ( !guts. clipboard_xfers)
						guts. clipboard_xfers = hash_create();
					if ( !CC-> xfers) 
						CC-> xfers = plist_create( 1, 1);
					if ( CC-> xfers && guts. clipboard_xfers) {
						ClipboardXfer * x = malloc( sizeof( ClipboardXfer));
						if ( x) {
							IV refcnt;
							ClipboardXferKey key;
							
							bzero( x, sizeof( ClipboardXfer));
							list_add( CC-> xfers, ( Handle) x);
							x-> size = CC-> internal[id]. size;
							x-> data = CC-> internal[id]. data;
							x-> blocks = ( x-> size / reqlen ) + ( x-> size % reqlen) ? 1 : 0;
							x-> requestor = xe. xselection. requestor;
							x-> property  = prop;
							x-> target    = xe. xselection. target;
							x-> self      = self;
							x-> format    = format;
							x-> id        = id;
							gettimeofday( &x-> time, nil);

							CLIPBOARD_XFER_KEY( key, x-> requestor, x-> property);
							hash_store( guts. clipboard_xfers, key, sizeof(key), (void*) x);
							refcnt = PTR2IV( hash_fetch( guts. clipboard_xfers, &x-> requestor, sizeof( XWindow)));
							if ( refcnt++ == 0)
								XSelectInput( DISP, x-> requestor, PropertyChangeMask|StructureNotifyMask); 
							hash_store( guts. clipboard_xfers, &x-> requestor, sizeof(XWindow), INT2PTR( void*, refcnt));

							format = CF_32;
							size = 1;
							incr = ( Atom) CC-> internal[id]. size;
							data = ( unsigned char*) &incr; 
							ok = 1;
							target = XA_INCR;
							Cdebug("clpboard: init INCR for %08x %d\n", x-> requestor, x-> property);
						}
					}
					if ( !ok) size = reqlen;
				}

				if ( format == CF_32) format = 32;
				XChangeProperty( 
					xe. xselection. display,
					xe. xselection. requestor,
					prop, target, format, mode, data, size);
				Cdebug("clipboard: store prop %s\n", XGetAtomName( DISP, prop));
				xe. xselection. property = prop;
			}

			/* content of PIXMAP or BITMAP is seemingly gets invalidated
				after the selection transfer, unlike the string data format */
			if ( id == cfBitmap) {
				bzero( CC-> internal[id].data, CC-> internal[id].size);
				bzero( CC-> external[id].data, CC-> external[id].size);
				clipboard_kill_item( CC-> internal, id);
				clipboard_kill_item( CC-> external, id);
			}
		}
SEND_EMPTY:
		XSendEvent( xe.xselection.display, xe.xselection.requestor, false, 0, &xe);
		XFlush( DISP);
		Cdebug("clipboard:id %d, SelectionNotify to %08x , %s %s\n", id, xe.xselection.requestor, 
			XGetAtomName( DISP, xe. xselection. property),
			XGetAtomName( DISP, xe. xselection. target)); 
	} break;
	case SelectionClear: 
		guts. last_time = ev-> xselectionclear. time;
		if ( XGetSelectionOwner( DISP, ev-> xselectionclear. selection) != WIN) {
			Handle c = ( Handle) hash_fetch( guts. clipboards, 
														&ev-> xselectionclear. selection, sizeof( Atom)); 
			guts. last_time = ev-> xselectionclear. time;
			if (c) {
				int i;
				C(c)-> selection_owner = nilHandle;  
				for ( i = 0; i < guts. clipboard_formats_count; i++) {
					detach_xfers( C(c), i, true);
					clipboard_kill_item( C(c)-> external, i);
					clipboard_kill_item( C(c)-> internal, i);
				}
			}
		}   
		break;
	case PropertyNotify:
		if ( ev-> xproperty. state == PropertyDelete) {
			unsigned long offs, size, reqlen = guts. limits. request_length - 4, format;
			ClipboardXfer * x = ( ClipboardXfer *) self;
			PClipboardSysData CC = C(x-> self);
			offs = x-> offset * reqlen;
			if ( offs >= x-> size) { /* clear termination */
				size = 0; 
				offs = 0;
			} else {
				size = x-> size - offs;
				if ( size > reqlen) size = reqlen;
			}
			Cdebug("clipboard: put %d %d in %08x %d\n", x-> offset, size, x-> requestor, x-> property); 
			if ( x-> format > 8)  size /= 2;
			if ( x-> format > 16) size /= 2;
			format = ( x-> format == CF_32) ? 32 : x-> format;
			XChangeProperty( DISP, x-> requestor, x-> property, x-> target,
				format, PropModeReplace, 
				x-> data + offs, size);
			XFlush( DISP);
			x-> offset++;
			if ( size == 0) delete_xfer( CC, x);
		}
		break;
	case DestroyNotify:
		Cdebug("clipboard: destroy xfers at %08x\n", ev-> xdestroywindow. window);
		hash_first_that( guts. clipboards, (void*)delete_xfers, (void*) &ev-> xdestroywindow. window, nil, nil);
		XFlush( DISP);
		break;
	}
	XCHECKPOINT;
}