// The Flesch Index
// Daniel Shiffman
// Programming from A to Z, Spring 2006

import java.io.*;
import java.nio.*;
import java.nio.channels.*;

import java.util.StringTokenizer;

public class FleschIndex {
  public static void main (String[] args) throws IOException {

    // Create an input stream and file channel
    // Using first arguemnt as file name to read in
    FileInputStream fis = new FileInputStream(args[0]);
    FileChannel fc = fis.getChannel();
  
    // Read the contents of a file into a ByteBuffer
    ByteBuffer bb = ByteBuffer.allocate((int)fc.size());
    fc.read(bb);
    fc.close();
    
    // Convert ByteBuffer to one long String
    String content = new String(bb.array());
    
    
    int syllables = 0;
    int sentences = 0;
    int words     = 0;

    String delimiters = ".,':;?{}[]=-+_!@#$%^&*() ";
    StringTokenizer tokenizer = new StringTokenizer(content,delimiters);
    //go through all words
    while (tokenizer.hasMoreTokens())
    {
      String word = tokenizer.nextToken();
      syllables += countSyllables(word);
      words++;
    }
    //look for sentence delimiters
    String sentenceDelim = ".:;?!";
    StringTokenizer sentenceTokenizer = new StringTokenizer(content,sentenceDelim);
    sentences = sentenceTokenizer.countTokens();
    
    //calculate flesch index
    final float f1 = (float) 206.835;
    final float f2 = (float) 84.6;
    final float f3 = (float) 1.015;
    float r1 = (float) syllables / (float) words;
    float r2 = (float) words / (float) sentences;
    float flesch = f1 - (f2*r1) - (f3*r2);

    //Write Report
    String report = "";
    
    report += "Total Syllables: " + syllables + "\n";
    report += "Total Words    : " + words + "\n";
    report += "Total Sentences: " + sentences + "\n";
    report += "Flesch Index   : " + flesch + "\n";
    System.out.println(report);

    // Create an output stream and file channel to write out a report
    // (Also print out report to screen)
    FileOutputStream fos = new FileOutputStream("report.txt");
    FileChannel outfc = fos.getChannel();
    
    // Convert content String into ByteBuffer and write out to file
    bb = ByteBuffer.wrap(report.getBytes());
    outfc.write(bb);
    outfc.close();

  }


// A method to count the number of syllables in a word
// Pretty basic, just based off of the number of vowels
// This could be improved
public static int countSyllables(String word) {
    int      syl    = 0;
    boolean  vowel  = false;
    int      length = word.length();

    //check each word for vowels (don't count more than one vowel in a row)
    for(int i=0; i<length; i++) {
      if        (isVowel(word.charAt(i)) && (vowel==false)) {
        vowel = true;
        syl++;
      } else if (isVowel(word.charAt(i)) && (vowel==true)) {
        vowel = true;
      } else {
        vowel = false;
      }
    }

    char tempChar = word.charAt(word.length()-1);
    //check for 'e' at the end, as long as not a word w/ one syllable
    if (((tempChar == 'e') || (tempChar == 'E')) && (syl != 1)) {
      syl--;
    }
    return syl;
}

//check if a char is a vowel (count y)
public static boolean isVowel(char c) {
    if      ((c == 'a') || (c == 'A')) { return true;  }
    else if ((c == 'e') || (c == 'E')) { return true;  }
    else if ((c == 'i') || (c == 'I')) { return true;  }
    else if ((c == 'o') || (c == 'O')) { return true;  }
    else if ((c == 'u') || (c == 'U')) { return true;  }
    else if ((c == 'y') || (c == 'Y')) { return true;  }
    else                               { return false; }
  }
}
