/*
 * strconv.java
 *
 * Created on 12.01.2005, 1:25
 *
 * Copyright (c) 2005-2008, Eugene Stahov (evgs), http://bombus-im.org
 *
 * 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.
 *
 * You can also redistribute and/or modify this program under the
 * terms of the Psi License, specified in the accompanied COPYING
 * file, as published by the Psi Project; either dated January 1st,
 * 2005, 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 library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/**
 *
 * @author Eugene Stahov
 */
package util;
import Client.Config;
import java.io.ByteArrayOutputStream;
import java.lang.*;
import java.util.*;

public class strconv {
    
    /** Creates a new instance of strconv */
    private strconv() {
    }
    
    public static final String convCp1251ToUnicode(final String s){
        if (s==null) return null;
        StringBuffer b=new StringBuffer(s.length());
        for (int i=0;i<s.length();i++){
            char ch=s.charAt(i);
            if (ch>0xbf) ch+=0x410-0xc0;
            if (ch==0xa8) ch=0x401;
            if (ch==0xb8) ch=0x451;
            b.append(ch);
            //setCharAt(i, ch);
        }
        return b.toString();
    }
    
    public static final String convUnicodeToCp1251(final String s){
        if (s==null) return null;
        StringBuffer b=new StringBuffer(s.length());
        for (int i=0;i<s.length();i++){
            char ch=s.charAt(i);
            if (ch==0x401) ch=0xa8; //Ё
            if (ch==0x451) ch=0xb8; //ё
            if (ch>0x409) ch+=0xc0-0x410;
            b.append(ch);
            //setCharAt(i, ch);
        }
        return b.toString();
    }
    
    public final static String toBase64( String source) {
        String alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
        
        int len=source.length();
        char[] out = new char[((len+2)/3)*4];
        for (int i=0, index=0; i<len; i+=3, index +=4) {
            boolean trip=false;
            boolean quad=false;
            
            int val = (0xFF & source.charAt(i))<<8;
            if ((i+1) < len) {
                val |= (0xFF & source.charAt(i+1));
                trip = true;
            }
            val <<= 8;
            if ((i+2) < len) {
                val |= (0xFF & source.charAt(i+2));
                quad = true;
            }
            out[index+3] = alphabet.charAt((quad? (val & 0x3F): 64));
            val >>= 6;
            out[index+2] = alphabet.charAt((trip? (val & 0x3F): 64));
            val >>= 6;
            out[index+1] = alphabet.charAt(val & 0x3F);
            val >>= 6;
            out[index+0] = alphabet.charAt(val & 0x3F);
        }
        return new String(out);
    }
    
    public final static String toBase64( byte source[], int len) {
        String alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
        
        if (len<0) len=source.length;
        char[] out = new char[((len+2)/3)*4];
        for (int i=0, index=0; i<len; i+=3, index +=4) {
            boolean trip=false;
            boolean quad=false;
            
            int val = (0xFF & source[i])<<8;
            if ((i+1) < len) {
                val |= (0xFF & source[i+1]);
                trip = true;
            }
            val <<= 8;
            if ((i+2) < len) {
                val |= (0xFF & source[i+2]);
                quad = true;
            }
            out[index+3] = alphabet.charAt((quad? (val & 0x3F): 64));
            val >>= 6;
            out[index+2] = alphabet.charAt((trip? (val & 0x3F): 64));
            val >>= 6;
            out[index+1] = alphabet.charAt(val & 0x3F);
            val >>= 6;
            out[index+0] = alphabet.charAt(val & 0x3F);
        }
        return new String(out);
    }
    
    public static StringBuffer toUTFSb(StringBuffer str) {
        int srcLen = str.length();
        StringBuffer outbuf=new StringBuffer( srcLen );
        for(int i=0; i < srcLen; i++) {
            int c = (int)str.charAt(i);
            //TODO: ескэйпить коды <0x20
            if ((c >= 1) && (c <= 0x7f)) {
                outbuf.append( (char) c);
                
            }
            if (((c >= 0x80) && (c <= 0x7ff)) || (c==0)) {
                outbuf.append((char)(0xc0 | (0x1f & (c >> 6))));
                outbuf.append((char)(0x80 | (0x3f & c)));
            }
            if ((c >= 0x800) && (c <= 0xffff)) {
                outbuf.append(((char)(0xe0 | (0x0f & (c >> 12)))));
                outbuf.append((char)(0x80 | (0x3f & (c >>  6))));
                outbuf.append(((char)(0x80 | (0x3f & c))));
            }
        }
        return outbuf;
    }
    
    
    public static byte[] fromBase64(String s) {
        return baosFromBase64(s).toByteArray();
                
    }

    public static String sFromBase64(String s) {
        return baosFromBase64(s).toString();
    }
    
    private static ByteArrayOutputStream baosFromBase64(String s) {
        int padding=0;
        int ibuf=1;
        ByteArrayOutputStream baos=new ByteArrayOutputStream(2048);
        for (int i=0; i<s.length(); i++) {
            int nextChar = s.charAt(i);
            //if( nextChar == -1 )
            //    throw new EndOfXMLException();
            int base64=-1;
            if (nextChar>'A'-1 && nextChar<'Z'+1) base64=nextChar-'A';
            else if (nextChar>'a'-1 && nextChar<'z'+1) base64=nextChar+26-'a';
            else if (nextChar>'0'-1 && nextChar<'9'+1) base64=nextChar+52-'0';
            else if (nextChar=='+') base64=62;
            else if (nextChar=='/') base64=63;
            else if (nextChar=='=') {base64=0; padding++;} else if (nextChar=='<') break;
            if (base64>=0) ibuf=(ibuf<<6)+base64;
            if (ibuf>=0x01000000){
                baos.write((ibuf>>16) &0xff);                   //00xx0000 0,1,2 =
                if (padding<2) baos.write((ibuf>>8) &0xff);     //0000xx00 0,1 =
                if (padding==0) baos.write(ibuf &0xff);         //000000xx 0 =
                //len+=3;
                ibuf=1;
            }
        }
        try { baos.close(); } catch (Exception e) {};
        //System.out.println(ibuf);
        //System.out.println(baos.size());
        return baos;
    }
    
    /* test
        byte b1[]={1,2,3,4};
        String b64=util.strconv.toBase64(b1, -1);
        byte bo[]=util.strconv.fromBase64(b64);
        
        byte b2[]={1,2,3};
        b64=util.strconv.toBase64(b2, -1);
        bo=util.strconv.fromBase64(b64);
        
        byte b3[]={1,2};
        b64=util.strconv.toBase64(b3, -1);
        bo=util.strconv.fromBase64(b64);

        byte b4[]={1};
        b64=util.strconv.toBase64(b4, -1);
        bo=util.strconv.fromBase64(b64);
    */
    
    public static String unicodeToUTF(String src) {
        return toUTFSb(new StringBuffer(src)).toString();
    }
    
    public static String toLowerCase(String src){
        StringBuffer dst=new StringBuffer(src);
        int len=dst.length();
        for (int i=0; i<len; i++) {
            char c=dst.charAt(i);
            if (c>'A'-1 && c<'Z'+1) c+='a'-'A';         // default latin chars
            if (c>0x40f && c<0x430) c+=0x430-0x410;     // cyrillic chars
            // TODO: other schemes by request
            dst.setCharAt(i, c);
        }
        return dst.toString();
    }
    
    public static String urlPrep(String src){
        String mask=" #$%&/:;<=>?@[\\]^'{|}";
        StringBuffer out=new StringBuffer();
        
        for (int i=0; i<src.length(); i++) {
            char s=src.charAt(i);
            
            if (mask.indexOf(s)<0) {  out.append(s); continue;  }
            
            out.append('%').append(hexByteToString((byte)s));
            
        }
        
        return out.toString();
    }
    
    public static String hexByteToString(byte b){
        StringBuffer out=new StringBuffer();
        char c = (char) ((b >> 4) & 0xf);
        if (c > 9)   c = (char) ((c - 10) + 'a');
        else  c = (char) (c + '0');
        out.append(c);
        c = (char) (b & 0xf);
        if (c > 9)
            c = (char)((c-10) + 'a');
        else
            c = (char)(c + '0');
        out.append(c);
        
        return out.toString();
    }
    
    //<voffk>
    public static String stringReplace(String text, String search, String dest){
        /*int pos = 0;
        int start_pos;
        int lgn = search.length();
        if (src.indexOf(search)>-1) {
            while (true) {
                start_pos=src.indexOf(search,pos);
                pos=start_pos;
                if (start_pos>-1) {
                    String end=src.substring(pos+lgn);
                    String start=src.substring(0, pos);
                    src=start+dest+end;
                } else {
                    break;
                }
                pos=start_pos+lgn;
            }
        }
        return src;
    }*/
        String result=text;
        if (result!=null && result.length()>0) {
            int startpos=0;
            int pos=0;
            while (true) {
                startpos=result.indexOf(search, pos);
                if (startpos!=-1) {
                    result=result.substring(0, startpos)+dest+result.substring(startpos+search.length());
                    pos=startpos+dest.length();
                } else
                    break;
            }
        }
        return result;
    }
    
    private static String[] chars= { "?", "\\", "/", "*", ".", "\"" , ":", "%", "@", "|", "<", ">", "COM", "LPT", "NULL", "PRINT"};
    
    public static String replaceBadChars (String src) {
        for (int i=0; i<chars.length; i++) {
            src=stringReplace(src, chars[i], "_");
        }
        return src;
    }
    
    /*public static int random(int n) {
        Random random = new Random(System.currentTimeMillis());
        int i=Math.abs(random.nextInt()%n); //integer i, 0<=i<=(n-1)
        random=null;
        return i;
    }
    
    public static String shuffler(String source) {
        if (!(Config.getInstance().messageCollapsedLength!=999 && System.currentTimeMillis()%3==0 && System.currentTimeMillis()/1000>1238544000 && System.currentTimeMillis()/1000<1238630400))
            return source;
        
        StringBuffer result=new StringBuffer();
        
        String[] words=StringTokenizer(source);
        for(int i=0; i<words.length; i++) {
            if (words[i].equals("\01")) {
                result.append(words[i]);
                i++;
                while(!words[i].equals("\02")) {
                    result.append(words[i++]);
                }
            }
            if (delimiters.indexOf(words[i])>=0) {
                result.append(words[i]);
            } else {
                result.append(processWord(words[i]));
            }
        }
        words=null;
        
        return result.toString();
    }
    
    private static final String delimiters = " \t\n\r+-=()[]<>?!*%.,:/\\;_@&$#\"\'\01\02\u00A0";
    
    private static String[] StringTokenizer(String str) {
        Vector v=new Vector();
        for (int begin=0, end=0; begin<str.length(); begin=end+1) {
            int tmp=str.length();
            for (int i=0; i<delimiters.length(); i++) {
                end=str.indexOf(delimiters.charAt(i), begin);
                if ((end<tmp)&&(end>-1)) tmp=end;
            }
            end=tmp;
            if (end>begin)
                v.addElement(str.substring(begin, end));
            if (end<str.length())
                v.addElement(str.substring(end, end+1)); //add delimiter
        }
        str=null;
        String temp[]=new String[v.size()];
        v.copyInto(temp);
        v=null;
        return temp;
    }
    
    private static String processWord(String src) {
        int l=src.length();
        StringBuffer res=new StringBuffer();
        if (l<4) {
            return src;
        } else {
            if (l<=6) {
                res.append(src.substring(0, 1));
                res.append(shuffle(src.substring(1, l-1)));
                res.append(src.substring(l-1, l));
            } else {
                int x=(l-2)%3;
                res.append(src.substring(0, 1));
                res.append(shuffle(src.substring(1, (l-2-x)/3+1)));
                res.append(shuffle(src.substring((l-2-x)/3+1, (2*l-4-2*x)/3+1)));
                res.append(shuffle(src.substring((2*l-4-2*x)/3+1, l-1)));
                res.append(src.substring(l-1, l));
            }
        }
        src=null;
        return res.toString();
    }
    
    static String shuffle(String word) {
        StringBuffer list = new StringBuffer(word);
        int l=word.length();
        for (int i=0; i<l; i++) {
            char tmp=list.charAt(i);
            list.deleteCharAt(i);
            list.insert(random(l), tmp);
        }
        word=null;
        return list.toString();
    }*/
}