import java.util.*;
//--
//import InsertText;

/**
 *  Provides one or two static methods dealing with
 *  blankness in pieces of text. 
 *
 *  @author http://bumble.sf.net
 */
 
  
public class BlankText extends Object
{
  //--------------------------------------------
  private static String NEWLINE = System.getProperty("line.separator");
  //--------------------------------------------
  private String text;  

  //--------------------------------------------
  public BlankText()
  {
    this.text = "";
  }

  //--------------------------------------------
  public BlankText(String sText)
  {
    this.text = sText;
  } 

  //--------------------------------------------
  /** what is a newline character is tricky */
  public static boolean lastLineIsBlank(String sText)
  {
    char cLast;
    
    if (sText.length() == 0)
    {
      return false;
    }

    if (!sText.endsWith(NEWLINE))
    {
      return false;
    }

    sText = EndText.removeSuffix(sText, NEWLINE);

    while (sText.length() > 0)
    {
      if (sText.endsWith(NEWLINE))
      {
        return true;
      }

      cLast = sText.charAt(sText.length() - 1);
      
      if (!Character.isWhitespace(cLast))
      {
        return false;
      }

      sText = EndText.removeLast(sText);
    } //-- while 

    return false;
  }

  //--------------------------------------------
  public static boolean lastCharacterIsBlank(String sText)
  {
    if (sText.length() == 0)
    {
      return false;
    }

    char cLast;
    cLast = sText.charAt(sText.length() - 1);

    if (Character.isWhitespace(cLast))
    {
      return true;
    }
    else
    {
      return false;
    }
  }

  //--------------------------------------------
  public static boolean firstCharacterIsBlank(String sText)
  {
    char cFirst;
    cFirst = sText.charAt(0);
    if (Character.isWhitespace(cFirst))
    {
      return true;
    }
    else
    {
      return false;
    }
  }

  //--------------------------------------------
  /** makes some space characters visible */
  public static String displayBlanks(String sText)
  {
    char cCurrent;
    StringBuffer sbReturn = new StringBuffer("");
    sbReturn.append(NEWLINE);
    sbReturn.append("<start-text>");
    for (int ii = 0; ii < sText.length(); ii++)
    {
      cCurrent = sText.charAt(ii);
      if (cCurrent == '!')
      {
        sbReturn.append("\\n");
        sbReturn.append(cCurrent);
      }
      else if (cCurrent == '!')
      {
        sbReturn.append("\\r");
        sbReturn.append(cCurrent);
      }
      else if (cCurrent == ' ')
      {
        sbReturn.append(".");
      }
      else if (cCurrent == '\t')
      {
        sbReturn.append(",");
      }
      else
      {
        sbReturn.append(cCurrent);
      }
    } //-- for

    sbReturn.append("<end-text>");
    return sbReturn.toString();

  } //-- m: displayBlanks

  //--------------------------------------------
  /** replaces a character in a string with a string */
  public static String replace(String sText, char cOld, String sNew)
  {
    char cCurrent;
    StringBuffer sbReturn = new StringBuffer("");

    if (sText.indexOf(cOld) == -1)
    {
      return sText;
    }

    for (int ii = 0; ii < sText.length(); ii++)
    {
      cCurrent = sText.charAt(ii);
      if (cCurrent == cOld)
      {
        sbReturn.append(sNew);
      }
      else
      {
        sbReturn.append(cCurrent);
      }
    } //-- for

    return sbReturn.toString();

  } //-- method: replace



  //--------------------------------------------
  /** a main method for testing */
  public static void main(String[] args) throws Exception
  {
    
    StringBuffer sbUsageMessage = new StringBuffer("");
    sbUsageMessage.append("test usage: java BlankText .");
    sbUsageMessage.append(NEWLINE);


    if (args.length == 0)
    {	    
      System.out.println(sbUsageMessage);
      System.exit(-1);
    }

    StringBuffer sbText = new StringBuffer("");
    sbText.append("This is the first line ");
    sbText.append(NEWLINE);
    sbText.append("This is the second line ");
    sbText.append(NEWLINE);
    sbText.append(" more writing here ");
    sbText.append(NEWLINE);
    sbText.append("      ");
    sbText.append(NEWLINE);

    char cReplace = args[0].charAt(0);
    String sNew = args[1];
        
    System.out.println("Using text:");
    System.out.println(sbText);
    System.out.println("");
                                         
    System.out.print(".displayBlanks()         >");
    System.out.println("");
    //System.out.println(BlankText.displayBlanks(sbText.toString()));
    System.out.print(".lastLineIsBlank()       >");
    System.out.println(BlankText.lastLineIsBlank(sbText.toString()));
    System.out.print(".firstCharacterIsBlank() >");
    System.out.println(BlankText.firstCharacterIsBlank(sbText.toString()));
    System.out.print(".lastCharacterIsBlank()  >");
    System.out.println(BlankText.lastCharacterIsBlank(sbText.toString()));
 
  } //-- main()
  
} //-- BlankText class