//***************************************
// Program Name: calcsoundex.java       *
// Author: Pat Moss                     *
// Date: Nov 12, 2005  Rev. 02          *
//                                      *
// Demonstrate class "calcsoundex", etc.*
//***************************************

// Receive an input data string from the user, and
// Generate an equivalent 4-character Soundex code
// of the form A123

// Soundex Code Examples include:

// Washington  W252
// Wu          W000
// DeSmet      D253
// Gutierrez   G362
// Pfister     P236
// Jackson     J250
// Tymczak     T522
// Ashcraft    A261 (or A226)
// Hammer      H560
// Moss        M200
// Phoenix     P520

// Reference URLs:
// www.highprogrammer.com/alan/numbers/soundex.html
// www.zynetwc.com/~storm/sounde~1.htm

import java.util.Scanner;

public class calcsoundex
{
 private final String ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
 private final String SDXCODES = "01230120022455012623010202";

 private String globalinpstr = ""; // user input data string
 private int globalinplen = 0;     // user input data string length

 private int globalidx = -1;  // Current user input data string processing index

 Scanner scan = new Scanner(System.in);

 // constructor
 calcsoundex()
 {
  initall();
 }

 // initialize all variables
 void initall()
 {
  globalinplen = 0;
 }

 // process the current user input string
 public void getUserData()
 {
   char codeprev = '-'; // Previous Soundex code
   char codecurr = ' '; // Current  Soundex code

   char nextchar = ' '; // Next character from user input string

   String outstr = "";  // Soundex code output string
   int outlen = 0;      // Soundex code output string length

   System.out.print ("Enter input string ('*' to Exit): ");
   globalinpstr = scan.nextLine().toUpperCase() + " ";

   // while #1: test for Exit sentinel value '*'
   while (globalinpstr.charAt(0) != '*') {
    // initialize variables
    initall();

    globalinplen = globalinpstr.length();
    globalidx = -1;

    outstr = "";
    outlen = 0;

    codeprev = '-';
    codecurr = ' ';

    nextchar = ' ';

    // loop until we have a 4-character Soundex code
    while (outlen < 4)      // while #2
    {
     nextchar = getChar();  // get next U.C. user input data char "A" to "Z"
     if (nextchar == '*')   // test for EOF sentinel value present
     {                      // yes: EOF sentinel value is present
      if (outlen == 0)      //      test for no valid user input data present
      {
       outlen++;            //      no valid user input data was present, 
       outstr += '-';       //      so provide a leading dummy character '-'
      }
 
      outlen++;             // EOF sentinel is present, so fill with a '0'
      outstr += '0';
     } else { // else #1    // valid data is present
                            // normal code processing entrance
      codeprev = codecurr;          // save prev char and use to elim dupls
      codecurr = getCode(nextchar); // get equivalent Soundex code character

      if (codecurr != codeprev) // if #1: bypass adjacent duplicate char codes
      {
       // first character is alpha, and other chars are non-zero Soundex codes
       if (outlen == 0) {       // if #2
        outlen++;
        outstr += nextchar;     // first character is alpha
       } else {
        if (codecurr != '0') {  // if #3:
                                // accept only non-zero Soundex code chars
         outlen++;
         outstr += codecurr;
        } // if #3
       }  // if #2
      }   // if #1
     }    // else #1
    }     // while #2
 
    System.out.print   ("The Soundex Code is: ");
    System.out.println (outstr);

    System.out.print ("Enter input string ('*' to Exit): ");
    globalinpstr = scan.nextLine().toUpperCase() + " ";
   } // while #1
 }

 // fetch the next alphabetic input character
 private char getChar()
 {
  while (globalidx < globalinplen)  // while #1
  {
   globalidx++;
   if (globalidx >= globalinplen)
    return ('*');    // reached end of user input data string
                     // so return an EOF sentinel value '*'

   // fetch the next user input data character
   char ch = globalinpstr.charAt(globalidx);

   // if the next input data character is alphabetic, then return it
   // otherwise keep looping
   if ((ch >= 'A') && (ch <= 'Z'))
    return (ch);
  } // while #1
  return ('*'); // reached end of user input data string
                // so return an EOF sentinel value '*'
 }

 // convert current U.C. alphabetic user input data char to a Soundex code
 private char getCode(char inpchar)
 {
  for (int i=0; i<26; i++)              // for #1
  { if (inpchar == ALPHABET.charAt(i))  // if #1
     return (SDXCODES.charAt(i));
  } // if #1
   return '-';  // error condition (should not occur)
 }  // for #1
}