/* This file is part of
* ======================================================
* 
*           LyX, The Document Processor
* 	 
*	    Copyright (C) 1995 Matthias Ettrich 
*           Copyright (C) 1995-1998 The LyX team.
*
*======================================================*/

#include <config.h>

#ifdef HAVE_XOPENIM
// This part is the full blown Input Method manager for X11R5 and up.
// For the plain-and-old-X11R4 version, see later.

#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/keysym.h>
#ifdef HAVE_LOCALE_H
#include <locale.h>
#endif

#include "error.h"

static XIM xim;
static XIC xic;
XComposeStatus compose_status={NULL,0};

// This is called after the main LyX window has been created
void InitLyXLookup(Display* display, Window window) 
{
	xic = NULL;

	// This part could be done before opening display
	setlocale(LC_CTYPE,"");
       	if (!XSupportsLocale()) {
		lyxerr.debug("InitLyXLookup: X does not support this locale.");
		return;
	} 
	if (!XSetLocaleModifiers("")) {
		lyxerr.debug("InitLyXLookup: Could not set modifiers "
			     "for this locale.");
		return;
	}

	// This part will have to be done for each frame
	xim = XOpenIM (display, NULL, NULL, NULL);
	if (xim) {
		xic = XCreateIC (xim,  
			    XNInputStyle, XIMPreeditNothing | XIMStatusNothing,
			    XNClientWindow, window,
			    XNFocusWindow, window, 
			    NULL);
		
		if (!xic) {
			lyxerr.debug("InitLyXLookup: could not create "
				     "an input context");
			XCloseIM (xim);
			xim = NULL;
		} 
	}
	else 
		lyxerr.debug("InitLyXLookup: could not open "
			     "an input method.");

}


static
bool isDeadEvent(XEvent *event,
		  char *buffer_return, int bytes_buffer,
		  KeySym *keysym_return)
{
	XLookupString(&event->xkey, buffer_return,
		      bytes_buffer, keysym_return,
		      NULL);
	// Can this be done safely in any other way?
	// This is all the dead keys I know of in X11R6.1
	if (false
#ifdef XK_dead_grave
	    || *keysym_return == XK_dead_grave
#endif
#ifdef XK_dead_acute
	    || *keysym_return == XK_dead_acute
#endif
#ifdef XK_dead_circumflex
	    || *keysym_return == XK_dead_circumflex
#endif
#ifdef XK_dead_tilde
	    || *keysym_return == XK_dead_tilde
#endif
#ifdef XK_dead_macron
	    || *keysym_return == XK_dead_macron
#endif
#ifdef XK_dead_breve
	    || *keysym_return == XK_dead_breve
#endif
#ifdef XK_dead_abovedot
	    || *keysym_return == XK_dead_abovedot
#endif
#ifdef XK_dead_diaeresis
	    || *keysym_return == XK_dead_diaeresis
#endif
#ifdef XK_dead_abovering
	    || *keysym_return == XK_dead_abovering
#endif
#ifdef XK_dead_doubleacute
	    || *keysym_return == XK_dead_doubleacute
#endif
#ifdef XK_dead_caron
	    || *keysym_return == XK_dead_caron
#endif
#ifdef XK_dead_cedilla
	    || *keysym_return == XK_dead_cedilla
#endif
#ifdef XK_dead_ogonek
	    || *keysym_return == XK_dead_ogonek
#endif
#ifdef XK_dead_iota
	    || *keysym_return == XK_dead_iota
#endif
#ifdef XK_dead_voiced_sound
	    || *keysym_return == XK_dead_voiced_sound
#endif
#ifdef XK_dead_semivoiced_sound
	    || *keysym_return == XK_dead_semivoiced_sound
#endif
#ifdef XK_dead_belowdot
	    || *keysym_return == XK_dead_belowdot
#endif
	    )
		return true;
	return false;
}


// This is called instead of XLookupString()
int LyXLookupString(XEvent *event,    
		    char *buffer_return, int bytes_buffer,
		    KeySym *keysym_return) 
{
	int result = 0;
	if (xic) {
		if (isDeadEvent(event, buffer_return, bytes_buffer,
				 keysym_return)) {
			return 0;
		}
		if (XFilterEvent (event, None)) {
			//lyxerr.print("XFilterEvent");
			*keysym_return = NoSymbol;
                        return 0;
		}
		if (event->type != KeyPress)
			lyxerr.print("LyXLookupString: wrong event type" 
				      +LString(event->type));
		Status status_return;
		
		result =  XmbLookupString(xic, &event->xkey, buffer_return,
				       bytes_buffer, keysym_return,
				       &status_return);
		switch(status_return) {
		case XLookupBoth:
			//lyxerr.print("XLookupBoth");
			break;
		case XLookupChars:
			//lyxerr.print("XLookupChars");
			*keysym_return = NoSymbol;
			break;
		case XLookupKeySym:
			//lyxerr.print("XLookupKeySym");
			result = 0;
			break;
		default:
			//lyxerr.print("default");
			*keysym_return = NoSymbol;
			result = 0;
			break;
		}
	} else {
		result = XLookupString(&event->xkey, buffer_return,
				  bytes_buffer, keysym_return,
				  &compose_status);
	}
	return result;
}

// This is called after the main window has been destroyed
void CloseLyXLookup() 
{
	if (xic) {
		lyxerr.debug("CloseLyXLookup: destroying input context");
		XDestroyIC(xic);
		XCloseIM(xim);
	}
}


#else // We do not have XOpenIM, so we stick with normal XLookupString

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

XComposeStatus compose_status={NULL,0};

// This is called after the main LyX window has been created
void InitLyXLookup(Display* , Window ) 
{
	//Nothing to do.
}

// This is called instead of XLookupString(). I this particular case,
// this *is* XLookupString...
int LyXLookupString(XEvent *event,    
		    char *buffer_return, int bytes_buffer,
		    KeySym *keysym_return) 
{
	return XLookupString(&event->xkey, buffer_return,
				  bytes_buffer, keysym_return,
				  &compose_status);
}

// This is called after the main window has been destroyed
void CloseLyXLookup() 
{
	// Nothing to do
}


#endif // HAVE_XOPENIM