/*
 * Aresh Saharkhiz
 * saharkiz@gmail.com
 * Associate Professor / Mapua Institute of Technology / Philippines
 */

using System;
using System.IO;
using System.Text;

// Introduction to Software Testing
// Authors: Paul Ammann & Jeff Offutt
// Chapter 2, section 2.5, page 80

/// <summary>
/// *****************************************************
/// // Stutter checks for repeat words in a text file.
/// // It prints a list of repeat words, by line number.
/// // Stutter will accept standard input or a list
/// // of file names.
///  Jeff Offutt, June 1989 (in C), Java version March 2003 
/// ********************************************************* 
/// </summary>

internal class Stutter
{
    // Class variables used in multiple methods.
    private static bool lastdelimit = true;
    private static string curWord = "", prevWord = "";
    private static char[] delimits = new char[] { '	', ' ', ',', '.', '!', '-', '+', '=', ';', ':', '?', '&', '{', '}', '\\' };

    //************************************************
    // main parses the arguments, decides if stdin
    // or a file name, and calls Stut().
    //************************************************
    //JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
    //ORIGINAL LINE: public static void main(String[] args) throws IOException
    public static void Main(string[] args)
{
   string fileName;
   StreamReader myFile;
   StreamReader inFile = null;

   if (args.Length == 0)
   { // no file, use stdin
       inFile = new StreamReader(new MemoryStream(Encoding.ASCII.GetBytes(Console.ReadLine())));
   }
   else
   {
	  fileName = args [0];
	  if (fileName == null)
	  { // no file name, use stdin
          inFile = new StreamReader(new MemoryStream(Encoding.ASCII.GetBytes(Console.ReadLine())));
	  }
	  else
	  { // file name, open the file.
          myFile = new StreamReader(fileName);
          inFile = myFile;
	  }
   }

   stut(inFile);
}

    //************************************************
    // Stut() reads all lines in the input stream, and
    // finds words. Words are defined as being surrounded
    // by delimiters as defined in the delimits[] array.
    // Every time an end of word is found, checkDupes()
    // is called to see if it is the same as the
    // previous word.
    //************************************************
    //JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
    //ORIGINAL LINE: private static void stut(BufferedReader inFile) throws IOException
    private static void stut(StreamReader inFile)
    {
        try
        {
            string inLine;
            char c;
            int linecnt = 1;
            while ((inLine = inFile.ReadLine()) != null)
            { // For each line

                for (int i = 0; i < inLine.Length; i++)
                { // for each character
                    c = inLine[i];

                    if (isDelimit(c))
                    { // Found an end of a word.
                        checkDupes(linecnt);
                    }
                    else
                    {
                        lastdelimit = false;
                        curWord = curWord + c;
                    }
                }
                checkDupes(linecnt);
                linecnt++;

            }
        }
        catch (Exception Ex)
        {
            Console.WriteLine(Ex.ToString());
        }
    } // end Stut

    //************************************************
    // checkDupes() checks to see if the globally defined
    // curWord is the same as prevWord and prints a message
    // if they are the same.
    //************************************************
    private static void checkDupes(int line)
    {
        if (lastdelimit)
        {
            return; // already checked, keep skipping
        }

        lastdelimit = true;
        if (curWord.Equals(prevWord))
        {
            Console.WriteLine("Repeated word on line " + line + ": " + prevWord + " " + curWord);
        }
        else
        {
            prevWord = curWord;
        }
        curWord = "";
    } // end checkDupes

    //************************************************
    // Checks to see if a character is a delimiter.
    //************************************************
    private static bool isDelimit(char C)
    {
        for (int i = 0; i < delimits.Length; i++)
        {
            if (C == delimits[i])
            {
                return (true);
            }
        }
        return (false);
    }

} // end class Stutter