//  Copyright (C) 2006  Andreas J. Resch
// 
// 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.
// 
// 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 program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin St, Fifth Floor, Boston, MA 02110, USA 


/*
 * StringUtil.java
 * Created on Mar 20, 2004
 *
 * $Author: andi $
 * $Date: 2006-07-21 17:56:39 $
 * 
 */
package at.anzac.util;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.StringTokenizer;


/********************************************************************
 * StringUtil is a collection of utility functions that handle strings.
 *******************************************************************/
public class StringUtil
{

  /** CVS-tag that starts dates */
  public final static String CVS_DATE_PREFIX     = "$Date: ";
  /** CVS-tag that starts revisions */
  public final static String CVS_REVISION_PREFIX = "$Revision: ";
  /** symbol that concludes all CVS-tags */
  public final static String CVS_POSTFIX         = " $";

  /** date formatter to get norm date */
  public static SimpleDateFormat   dateFormat=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

  /*********************************************************************************
   * get current date & time as as string in format "yyyy-MM-dd HH:mm:ss".
   * @return date & time as string
   ********************************************************************************/
  public static String getDateTime()
  {
    return dateFormat.format(new Date(System.currentTimeMillis()));
  }
  
  /*********************************************************************************
   * get a specific date & time as as string in format "yyyy-MM-dd HH:mm:ss".
   * @param time date&time to convert to string
   * @return date & time as string
   ********************************************************************************/
  public static String getDateTime(long time)
  {
    return dateFormat.format(new Date(time));
  }
  
  /********************************************************************
   * get the stacktrace of a {@link Throwable} as {@link String}.
   * @param t throwable to get the stacktarce of
   * @return stacktrace as string
   *******************************************************************/
  public static String getStackTrace(Throwable t)
  {
    StringWriter sw;

    sw = new StringWriter();
    t.printStackTrace(new PrintWriter(sw));

    return sw.toString();
  }


  /********************************************************************
   * extract the date from a substituted CVS date keyword.
   * on error an empty string is returned.
   * @param cvsDate string containg the CVS date keyword.
   * @return date extracted from cvsDate
   *******************************************************************/
  public static String extractCVSDate(String cvsDate)
  {
    return extractEnclosedString(cvsDate,CVS_DATE_PREFIX,CVS_POSTFIX).replace('/','-');
  }


  /********************************************************************
   * extract the revision from a substituted CVS revision keyword.
   * on error an empty string is returned.
   * @param cvsRevision string containg the CVS revision keyword.
   * @return revision extracted from cvs revision
   *******************************************************************/
  public static String extractCVSRevision(String cvsRevision)
  {
    return extractEnclosedString(cvsRevision,CVS_REVISION_PREFIX,CVS_POSTFIX);
  }


  /********************************************************************
   * extract a substring that is enclosed between a prefix i.e. leading
   * string and postfix i.e. trailing string.
   * on error an empty string is returned.
   * @param str string to extract the substring from
   * @param prefix string the precedes the desired sunstring
   * @param postfix string the follows the desired string
   * @return extracted substring
   *******************************************************************/
  public static String extractEnclosedString(String str,String prefix,String postfix)
  {
    int first, last;

    if(str == null)
    {
      return "";
    }

    first = str.indexOf(prefix);
    if(first < 0)
    {
      return "";
    }

    first += prefix.length();
    if(first >= str.length())
    {
      return "";
    }

    last = str.indexOf(postfix, first + 1);
    if(last < 0)
    {
      return "";
    }

    return str.substring(first, last);
  }


  /**********************************************************************************
   * remove all occurances of certain character from a string.
   * @param src	 string to remove characters from
   * @param chars characters to remove
   * @return string bereft of all caharcters in chars
   *********************************************************************************/
  public static String remove(String src, String chars)
  {
    StringBuffer buff;
    StringTokenizer tok;

    buff = new StringBuffer();
    tok = new StringTokenizer(src, chars);

    while(tok.hasMoreTokens())
    {
      buff.append(tok.nextToken());
    }

    return buff.toString();
  }


  /**********************************************************************************
   * convert a german formatted number so that it can be parsed by Double and Integer.
   * converts numbers like 60.578.648,12 to 60578648.12 or 60.578.648,-- to 60578648.00
   * so they can be processed by methods like {@link Integer#parseInt(java.lang.String)}.  
   * @param number to be reformatted
   * @return reformatted number
   *********************************************************************************/
  public static String convertNumberString(String number)
  {
    return remove(number, ".").replace(',', '.').replace('-', '0');
  }


  /**********************************************************************************
   * get the first <code>len</code> characters of a string.
   * if the sthe string is shorter than <code>len</code> the original string is 
   * returned thus this is like the standard substr(0,len) but it does not produce
   * an error when the string is too short.
   * @param str string to get a substring from
   * @param len number of characters to get
   * @return first <code>len</code> characters or less
   *********************************************************************************/
  public static String substr(String str,int len)
  {
    if(str.length()<=len)
    {
      return str;
    }
    
    return str.substring(0,len);
  }
  
  /**********************************************************************************
   * replace all occurances of a substring.
   * @param src string in which to replace
   * @param a substring that is to be replaced
   * @param b substring to replace with
   * @return copy of src where all occurances of a are replaced by b
   *********************************************************************************/
  public static String replaceAll(String src,String a,String b)
  {
    int     i,lenA,lenB;
    String  str;
    
    str=src;
    lenA=a.length();
    lenB=b.length();
    
    i=str.indexOf(a);
    while(i>=0)
    {
      str=str.substring(0,i)+b+str.substring(i+lenA);
      i=str.indexOf(a,i+lenB);
    }
    
    return str;
  }
  
  /**********************************************************************************
   * remove all characters from a string that may not be contained in file names.
   * @param str string to sanitize
   * @return <code>str</code> with all caharcters, that are not allowed in filenames
   * replaced by "_"
   *********************************************************************************/
  public static String sanitizeFileName(String str)
  {
    String sane;
    
    sane=replaceAll(str,"/","_");
    sane=replaceAll(sane,"\\","_");
    sane=replaceAll(sane,"?","_");
    sane=replaceAll(sane,"*","_");
    sane=replaceAll(sane,"\"","_");
    sane=replaceAll(sane,"'","_");
    sane=replaceAll(sane,":","_");
    sane=replaceAll(sane,"<","_");
    sane=replaceAll(sane,">","_");
    sane=replaceAll(sane,"|","_");
    
    return sane;
  }
  
}

// ----------------------------------------------------------------------
//
// $Log: StringUtil.java,v $
// Revision 1.13  2006-07-21 17:56:39  andi
// added replaceAll().
// added sanitizeString().
//
// Revision 1.12  2006-02-03 15:03:59  AJR
// added GPL statement.
//
// Revision 1.11  2005/01/05 18:21:07  AJR
// added substr().
//
// Revision 1.10  2004/12/21 17:53:55  AJR
// added getDateTime(long).
//
// Revision 1.9  2004/12/13 13:10:46  EXTCVS
// added getDateTime().
//
// Revision 1.8  2004/11/05 15:47:19  EXTCVS
// added comments.
//
// Revision 1.7  2004/10/03 16:46:41  AJR
// fixed bug in extractEnclosedString().
//
// Revision 1.6  2004/10/03 13:39:08  AJR
// added extractEnclosedString().
// added extractCVSRevision().
//
// Revision 1.5  2004/10/03 10:46:49  AJR
// implemented compliance to stricter compiler settings.
//
// Revision 1.4  2004/08/21 21:19:55  AJR
// added comments.
// convertNumberString now alre replaces ,-- by .00 .
//
// Revision 1.3  2004/08/21 13:24:31  AJR
// added convertNumberString().
// added remove().
//
// Revision 1.2  2004/04/11 11:04:54  AJR
// added extractCVSDate().
//
// Revision 1.1  2004/03/22 16:51:17  AJR
// created.
//
//----------------------------------------------------------------------