/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: NPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Netscape Public License
 * Version 1.1 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/NPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Communicator client code.
 *
 * The Initial Developer of the Original Code is 
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
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 * ***** END LICENSE BLOCK ***** */


#include "nsUnicodeToUEscape.h"
#include "nsUCSupport.h"
#include <string.h>

char hexarray[]="0123456789ABCDEF";
NS_IMETHODIMP nsUnicodeToUEscape::Convert(const PRUnichar * aSrc, PRInt32 * aSrcLength, 
      char * aDest, PRInt32 * aDestLength)
{
  const PRUnichar *src = aSrc;
  const PRUnichar *srcEnd = aSrc + *aSrcLength;
  char * dest = aDest;
  const char * destEnd = aDest + *aDestLength;
 
  while(( src < srcEnd) && (dest<destEnd))
  {
     if(0x0000 == ( 0xFF80 & (*src)) )
     {
       if( PRUnichar('\\') == *src)
       {
           if(( PRUnichar('n') == *(1+src))||
              ( PRUnichar('r') == *(1+src))||
              ( PRUnichar('t') == *(1+src))) 
           {
             *dest++ = (char) *src;
           } else {
             if((dest +2 ) >= destEnd)
               goto error;
             *dest++ = (char) '\\';
             *dest++ = (char) '\\';
           }
       } else {
           *dest++ = (char) *src;
       }
     } else {
       if((dest +6 ) >= destEnd)
         goto error;
       *dest++ = (char) '\\';
       *dest++ = (char) 'u';
       *dest++ = (char) hexarray[0x0f & (*src >> 12)];
       *dest++ = (char) hexarray[0x0f & (*src >> 8)];
       *dest++ = (char) hexarray[0x0f & (*src >> 4)];
       *dest++ = (char) hexarray[0x0f & (*src)];
     }
     src++;
  }

  *aSrcLength = src - aSrc;
  *aDestLength = dest - aDest;
  return NS_OK;
error:
  *aSrcLength = src - aSrc;
  *aDestLength = dest - aDest;
  return NS_OK_UDEC_MOREOUTPUT;
}
nsresult NEW_UnicodeToUEscape(nsISupports **aResult)
{
   *aResult = (nsIUnicodeEncoder*)new nsUnicodeToUEscape();
   return (NULL == *aResult) ? NS_ERROR_OUT_OF_MEMORY : NS_OK;
}    
