/*

 * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 *******************************************************************************

 * Copyright (C) 2003-2004, International Business Machines Corporation and    *

 * others. All Rights Reserved.                                                *

 *******************************************************************************

*/

import java.io.IOException;

import java.io.InputStream;

import java.io.UnsupportedEncodingException;

import java.text.ParseException;

import sun.text.normalizer.ICUData;

import sun.net.idn.StringPrep;

import sun.text.normalizer.UCharacterIterator;

/**

 * @author ram

 *

 * This is a dumb implementation of NFS4 profiles. It is a direct port of

 * C code, does not use Object Oriented principles. Quick and Dirty implementation

 * for testing.

 */

public final class NFS4StringPrep {

    private StringPrep nfscss = null;

    private StringPrep nfscsi = null;

    private StringPrep nfscis = null;

    private StringPrep nfsmxp = null;

    private StringPrep nfsmxs = null;

    //singleton instance

    private static final NFS4StringPrep prep = new NFS4StringPrep();

    private  NFS4StringPrep (){

        ClassLoader loader = NFS4StringPrep.class.getClassLoader();

      try{

          InputStream  nfscsiFile = loader.getResourceAsStream("nfscsi.spp");

          nfscsi = new StringPrep(nfscsiFile);

          nfscsiFile.close();

          InputStream  nfscssFile = loader.getResourceAsStream("nfscss.spp");

          nfscss = new StringPrep(nfscssFile);

          nfscssFile.close();

          InputStream  nfscisFile = loader.getResourceAsStream("nfscis.spp");

          nfscis = new StringPrep(nfscisFile);

          nfscisFile.close();

          InputStream  nfsmxpFile = loader.getResourceAsStream("nfsmxp.spp");

          nfsmxp = new StringPrep(nfsmxpFile);

          nfsmxpFile.close();

          InputStream  nfsmxsFile = loader.getResourceAsStream("nfsmxs.spp");

          nfsmxs = new StringPrep(nfsmxsFile);

          nfsmxsFile.close();

      }catch(IOException e){

          throw new RuntimeException(e.toString());

      }

    }

    private static byte[] prepare(byte[] src, StringPrep prep)

                throws ParseException, UnsupportedEncodingException{

        String s = new String(src, "UTF-8");

        UCharacterIterator iter =  UCharacterIterator.getInstance(s);

        StringBuffer out = prep.prepare(iter,StringPrep.DEFAULT);

        return out.toString().getBytes("UTF-8");

    }

    public static byte[] cs_prepare(byte[] src, boolean isCaseSensitive)

                         throws ParseException, UnsupportedEncodingException{

        if(isCaseSensitive == true ){

            return prepare(src, prep.nfscss);

        }else{

            return prepare(src, prep.nfscsi);

        }

    }

    public static byte[] cis_prepare(byte[] src)

                         throws IOException, ParseException, UnsupportedEncodingException{

        return prepare(src, prep.nfscis);

    }

    /* sorted array for binary search*/

    private static final String[] special_prefixes={

        "ANONYMOUS",

        "AUTHENTICATED",

        "BATCH",

        "DIALUP",

        "EVERYONE",

        "GROUP",

        "INTERACTIVE",

        "NETWORK",

        "OWNER",

    };

    /* binary search the sorted array */

    private static final int findStringIndex(String[] sortedArr,String target){

        int left, middle, right,rc;

        left =0;

        right= sortedArr.length-1;

        while(left <= right){

            middle = (left+right)/2;

            rc= sortedArr[middle].compareTo(target);

            if(rc<0){

                left = middle+1;

            }else if(rc >0){

                right = middle -1;

            }else{

                return middle;

            }

        }

        return -1;

    }

    private static final char AT_SIGN = '@';

    public static byte[] mixed_prepare(byte[] src)

                         throws IOException, ParseException, UnsupportedEncodingException{

        String s = new String(src, "UTF-8");

        int index = s.indexOf(AT_SIGN);

        StringBuffer out = new StringBuffer();

        if(index > -1){

            /* special prefixes must not be followed by suffixes! */

            String prefixString = s.substring(0,index);

            int i= findStringIndex(special_prefixes, prefixString);

            String suffixString = s.substring(index+1, s.length());

            if(i>-1 && !suffixString.equals("")){

                throw new ParseException("Suffix following a special index", -1);

            }

            UCharacterIterator prefix = UCharacterIterator.getInstance(prefixString);

            UCharacterIterator suffix = UCharacterIterator.getInstance(suffixString);

            out.append(prep.nfsmxp.prepare(prefix,StringPrep.DEFAULT));

            out.append(AT_SIGN); // add the delimiter

            out.append(prep.nfsmxs.prepare(suffix, StringPrep.DEFAULT));

        }else{

            UCharacterIterator iter = UCharacterIterator.getInstance(s);

            out.append(prep.nfsmxp.prepare(iter,StringPrep.DEFAULT));

        }

       return out.toString().getBytes("UTF-8");

    }

}