function double_metaphone( string )
{
   primary   = "";
   secondary = "";
   current   =  0;
    
    current  = 0;
    length   = string.length;
    last     = length - 1;
    original = string + "     ";

    original = original.toUpperCase();

    // skip this at beginning of word
    
    if (string_at(original, 0, 2, 
                        ['GN', 'KN', 'PN', 'WR', 'PS']))
      current++;

    // Initial 'X' is pronounced 'Z' e.g. 'Xavier'
    
    if (original.substr(0, 1) == 'X') {
      primary   += "S";   // 'Z' maps to 'S'
      secondary += "S";
      current++;
    }

    // main loop

    while (primary.length < 12 || secondary.length < 12) {
      if (current >= length)
        break;      
      switch (original.substr(current, 1)) {
        case 'A':
        case 'E':
        case 'I':
        case 'O':
        case 'U':
        case 'Y':
          if (current == 0) {
            // all init vowels now map to 'A'
            primary   += 'A';
            secondary += 'A';
          }
          current += 1;
          break;

        case 'B':
          // '-mb', e.g. "dumb", already skipped over ...
          primary   += 'P';
          secondary += 'P';

          if (original.substr(current + 1, 1) == 'B')
            current += 2;
          else
            current += 1;
          break;

        case 'Ç':
          primary   += 'S';
          secondary += 'S';
          current += 1;
          break;

        case 'C':
          // various gremanic
          if ((current > 1) 
              && !is_vowel(original, current - 2)
              && string_at(original, current - 1, 3, 
                        ["ACH"])
              && ((original.substr(current + 2, 1) != 'I')
                  && ((original.substr(current + 2, 1) != 'E')
                      || string_at(original, current - 2, 6, 
                                ["BACHER", "MACHER"])))) {

            primary   += 'K';
            secondary += 'K';
            current += 2;
            break;
          }

          // special case 'caesar'
          if ((current == 0) 
              && string_at(original, current, 6, 
                         ["CAESAR"])) {
            primary   += 'S';
            secondary += 'S';
            current += 2;
            break;
          }

          // italian 'chianti'
          if (string_at(original, current, 4, 
                         ["CHIA"])) {
            primary   += 'K';
            secondary += 'K';
            current += 2;
            break;
          }

          if (string_at(original, current, 2, 
                         ["CH"])) {

            // find 'michael'
            if ((current > 0)
                && string_at(original, current, 4, 
                         ["CHAE"])) {
              primary   += 'K';
              secondary += 'X';
              current += 2;
              break;
            }

            // greek roots e.g. 'chemistry', 'chorus'
            if ((current == 0)
                && (string_at(original, current + 1, 5, 
                         ["HARAC", "HARIS"])
                    || string_at(original, current + 1, 3, 
                              ["HOR", "HYM", "HIA", "HEM"]))
                && !string_at(original, 0, 5, ["CHORE"])) {
              primary   += 'K';
              secondary += 'K';
              current += 2;
              break;
            }

            // germanic, greek, or otherwise 'ch' for 'kh' sound
            if ((string_at(original, 0, 4, ["VAN ", "VON "])
                 || string_at(original, 0, 3, ["SCH"]))
                // 'architect' but not 'arch', orchestra', 'orchid'
                || string_at(original, current - 2, 6, 
                         ["ORCHES", "ARCHIT", "ORCHID"])
                || string_at(original, current + 2, 1, 
                         ["T", "S"])
                || ((string_at(original, current - 1, 1, 
                         ["A","O","U","E"])
                     || (current == 0))
                    // e.g. 'wachtler', 'weschsler', but not 'tichner'
                    && string_at(original, current + 2, 1, 
                         ["L","R","N","M","B","H","F","V","W"," "]))) {
              primary   += 'K';
              secondary += 'K';
            } else {
              if (current > 0) {
                if (string_at(original, 0, 2, ["MC"])) {
                  // e.g. 'McHugh'
                  primary   += 'K';
                  secondary += 'K';
                } else {
                  primary   += 'X';
                  secondary += 'K';
                }
              } else {
                primary   += 'X';
                secondary += 'X';
              }
            }
            current += 2;
            break;
          }

          // e.g. 'czerny'
          if (string_at(original, current, 2, ["CZ"])
              && !string_at(original, current -2, 4, 
                         ["WICZ"])) {
            primary   += 'S';
            secondary += 'X';
            current += 2;
            break;
          }

          // e.g. 'focaccia'
          if (string_at(original, current + 1, 3, 
                     ["CIA"])) {
            primary   += 'X';
            secondary += 'X';
            current += 3;
            break;
          }

          // double 'C', but not McClellan'
          if (string_at(original, current, 2, ["CC"])
              && !((current == 1) 
                   && (original.substr(0, 1) == 'M'))) {
            // 'bellocchio' but not 'bacchus'
            if (string_at(original, current + 2, 1,
                       ["I","E","H"])
                && !string_at(original, current + 2, 2,
                          ["HU"])) {
              // 'accident', 'accede', 'succeed'
              if (((current == 1)
                   && (original.substr(current - 1, 1) == 'A'))
                  || string_at(original, current - 1, 5,
                            ["UCCEE", "UCCES"])) {
                primary   += "KS";
                secondary += "KS";
                // 'bacci', 'bertucci', other italian
              } else {
                primary   += "X";
                secondary += "X";
              }
              current += 3;
              break;
            } else {
              // Pierce's rule
              primary   += "K";
              secondary += "K";
              current += 2;
              break;
            }
          }

          if (string_at(original, current, 2,
                     ["CK","CG","CQ"])) {
            primary   += "K";
            secondary += "K";
            current += 2;
            break;
          }

          if (string_at(original, current, 2,
                     ["CI","CE","CY"])) {
            // italian vs. english
            if (string_at(original, current, 3,
                       ["CIO","CIE","CIA"])) {
              primary   += "S";
              secondary += "X";
            } else {
              primary   += "S";
              secondary += "S";
            }
            current += 2;
            break;
          }

          // else
          primary   += "K";
          secondary += "K";

          // name sent in 'mac caffrey', 'mac gregor'
          if (string_at(original, current + 1, 2,
                     [" C"," Q"," G"])) {
            current += 3;
          } else {
            if (string_at(original, current + 1, 1,
                       ["C","K","Q"])
                && !string_at(original, current + 1, 2,
                           ["CE","CI"])) {
              current += 2;
            } else {
              current += 1;
            }
          }
          break;

        case 'D':
          if (string_at(original, current, 2,
                     ["DG"])) {
            if (string_at(original, current + 2, 1,
                       ["I","E","Y"])) {
              // e.g. 'edge'
              primary   += "J";
              secondary += "J";
              current += 3;
              break;
            } else {
              // e.g. 'edgar'
              primary   += "TK";
              secondary += "TK";
              current += 2;
              break;
            }
          }

          if (string_at(original, current, 2,
                     ["DT","DD"])) {
            primary   += "T";
            secondary += "T";
            current += 2;
            break;
          }

          // else
          primary   += "T";
          secondary += "T";
          current += 1;
          break;

        case 'F':
          if (original.substr(current + 1, 1) == 'F')
            current += 2;
          else
            current += 1;
          primary   += "F";
          secondary += "F";
          break;

        case 'G':
          if (original.substr(current + 1, 1) == 'H') {
            if ((current > 0) 
                && !is_vowel(original, current - 1)) {
              primary   += "K";
              secondary += "K";
              current += 2;
              break;
            }

            if (current < 3) {
              // 'ghislane', 'ghiradelli'
              if (current == 0) {
                if (original.substr(current + 2, 1) == 'I') {
                  primary   += "J";
                  secondary += "J";
                } else {
                  primary   += "K";
                  secondary += "K";
                }
                current += 2;
                break;
              }
            }

            // Parker's rule (with some further refinements) - e.g. 'hugh'
            if (((current > 1)
                 && string_at(original, current - 2, 1,
                           ["B","H","D"]))
                // e.g. 'bough'
                || ((current > 2)
                    &&  string_at(original, current - 3, 1,
                               ["B","H","D"]))
                // e.g. 'broughton'
                || ((current > 3)
                    && string_at(original, current - 4, 1,
                               ["B","H"]))) {
              current += 2;
              break;
            } else {
              // e.g. 'laugh', 'McLaughlin', 'cough', 'gough', 'rough', 'tough'
              if ((current > 2)
                  && (original.substr(current - 1, 1) == 'U')
                  && string_at(original, current - 3, 1,
                            ["C","G","L","R","T"])) {
                primary   += "F";
                secondary += "F";
              } else if ( (current > 0) && original.substr(current - 1, 1) != 'I') {
                primary   += "K";
                secondary += "K";
              }
              current += 2;
              break;
            }
          }

          if (original.substr(current + 1, 1) == 'N') {
            if ((current == 1) && is_vowel(original, 0)
                && !Slavo_Germanic(original)) {
              primary   += "KN";
              secondary += "N";
            } else {
              // not e.g. 'cagney'
              if (!string_at(original, current + 2, 2,
                          ["EY"])
                  && (original.substr(current + 1) != "Y")
                  && !Slavo_Germanic(original)) {
                 primary   += "N";
                 secondary += "KN";
              } else {
                 primary   += "KN";
                 secondary += "KN";
              }
            }
            current += 2;
            break;
          }

          // 'tagliaro'
          if (string_at(original, current + 1, 2,
                     ["LI"])
              && !Slavo_Germanic(original)) {
            primary   += "KL";
            secondary += "L";
            current += 2;
            break;
          }

          // -ges-, -gep-, -gel- at beginning
          if ((current == 0)
              && ((original.substr(current + 1, 1) == 'Y')
                  || string_at(original, current + 1, 2,
                            ["ES","EP","EB","EL","EY","IB","IL","IN","IE",
                                  "EI","ER"]))) {
            primary   += "K";
            secondary += "J";
            current += 2;
            break;
          }

          // -ger-, -gy-
          if ((string_at(original, current + 1, 2,
                      ["ER"])
               || (original.substr(current + 1, 1) == 'Y'))
              && !string_at(original, 0, 6,
                         ["DANGER","RANGER","MANGER"])
              && !string_at(original, current -1, 1,
                         ["E", "I"])
              && !string_at(original, current -1, 3,
                         ["RGY","OGY"])) {
            primary   += "K";
            secondary += "J";
            current += 2;
            break;
          }

          // italian e.g. 'biaggi'
          if (string_at(original, current + 1, 1,
                     ["E","I","Y"])
              || string_at(original, current -1, 4,
                        ["AGGI","OGGI"])) {
            // obvious germanic
            if ((string_at(original, 0, 4, ["VAN ", "VON "])
                 || string_at(original, 0, 3, ["SCH"]))
                || string_at(original, current + 1, 2,
                          ["ET"])) {
              primary   += "K";
              secondary += "K";
            } else {
              // always soft if french ending
              if (string_at(original, current + 1, 4,
                         ["IER "])) {
                primary   += "J";
                secondary += "J";
              } else {
                primary   += "J";
                secondary += "K";
              }
            }
            current += 2;
            break;
          }

          if (original.substr(current +1, 1) == 'G')
            current += 2;
          else
            current += 1;

          primary   += 'K';
          secondary += 'K';
          break;

        case 'H':
          // only keep if first & before vowel or btw. 2 vowels
          if (((current == 0) || 
               is_vowel(original, current - 1))
              && is_vowel(original, current + 1)) {
            primary   += 'H';
            secondary += 'H';
            current += 2;
          } else
            current += 1;
          break;

        case 'J':
          // obvious spanish, 'jose', 'san jacinto'
          if (string_at(original, current, 4,
                     ["JOSE"])
              || string_at(original, 0, 4, ["SAN "])) {
            if (((current == 0)
                 && (original.substr(current + 4, 1) == ' '))
                || string_at(original, 0, 4, ["SAN "])) {
              primary   += 'H';
              secondary += 'H';
            } else {
              primary   += "J";
              secondary += 'H';
            }
            current += 1;
            break;
          }

          if ((current == 0)
              && !string_at(original, current, 4,
                     ["JOSE"])) {
            primary   += 'J';  // Yankelovich/Jankelowicz
            secondary += 'A';
          } else {
            // spanish pron. of .e.g. 'bajador'
            if (is_vowel(original, current - 1)
                && !Slavo_Germanic(original)
                && ((original.substr(current + 1, 1) == 'A')
                    || (original.substr(current + 1, 1) == 'O'))) {
              primary   += "J";
              secondary += "H";
            } else {
              if (current == last) {
                primary   += "J";
                secondary += "";
              } else {
                if (!string_at(original, current + 1, 1,
                            ["L","T","K","S","N","M","B","Z"])
                    && !string_at(original, current - 1, 1,
                               ["S","K","L"])) {
                  primary   += "J";
                  secondary += "J";
                }
              }
            }
          }

          if (original.substr(current + 1, 1) == 'J') // it could happen
            current += 2;
          else 
            current += 1;
          break;

        case 'K':
          if (original.substr(current + 1, 1) == 'K')
            current += 2;
          else
            current += 1;
          primary   += "K";
          secondary += "K";
          break;

        case 'L':
          if (original.substr(current + 1, 1) == 'L') {
            // spanish e.g. 'cabrillo', 'gallegos'
            if (((current == (length - 3))
                 && string_at(original, current - 1, 4,
                           ["ILLO","ILLA","ALLE"]))
                || ((string_at(original, last-1, 2,
                            ["AS","OS"])
                  || string_at(original, last, 1,
                            ["A","O"]))
                 && string_at(original, current - 1, 4,
                           ["ALLE"]))) {
              primary   += "L";
              secondary += "";
              current += 2;
              break;
            }
            current += 2;
          } else 
            current += 1;
          primary   += "L";
          secondary += "L";
          break;

        case 'M':
          if ((string_at(original, current - 1, 3,
                     ["UMB"])
               && (((current + 1) == last)
                   || string_at(original, current + 2, 2,
                            ["ER"])))
              // 'dumb', 'thumb'
              || (original.substr(current + 1, 1) == 'M')) {
              current += 2;
          } else {
              current += 1;
          }
          primary   += "M";
          secondary += "M";
          break;

        case 'N':
          if (original.substr(current + 1, 1) == 'N') 
            current += 2;
          else
            current += 1;
          primary   += "N";
          secondary += "N";
          break;

        case 'Ñ':
          current += 1;
          primary   += "N";
          secondary += "N";
          break;

        case 'P':
          if (original.substr(current + 1, 1) == 'H') {
            current += 2;
            primary   += "F";
            secondary += "F";
            break;
          }

          // also account for "campbell" and "raspberry"
          if (string_at(original, current + 1, 1,
                     ["P","B"]))
            current += 2;
          else
            current += 1;
          primary   += "P";
          secondary += "P";
          break;

        case 'Q':
          if (original.substr(current + 1, 1) == 'Q') 
            current += 2;
          else 
            current += 1;
          primary   += "K";
          secondary += "K";
          break;

        case 'R':
          // french e.g. 'rogier', but exclude 'hochmeier'
          if ((current == last)
              && !Slavo_Germanic(original)
              && string_at(original, current - 2, 2,
                        ["IE"])
              && !string_at(original, current - 4, 2,
                         ["ME","MA"])) {
            primary   += "";
            secondary += "R";
          } else {
            primary   += "R";
            secondary += "R";
          }
          if (original.substr(current + 1, 1) == 'R') 
            current += 2;
          else
            current += 1;
          break;

        case 'S':
          // special cases 'island', 'isle', 'carlisle', 'carlysle'
          if (string_at(original, current - 1, 3,
                     ["ISL","YSL"])) {
            current += 1;
            break;
          }

          // special case 'sugar-'
          if ((current == 0)
              && string_at(original, current, 5,
                        ["SUGAR"])) {
            primary   += "X";
            secondary += "S";
            current += 1;
            break;
          }

          if (string_at(original, current, 2,
                     ["SH"])) {
            // germanic
            if (string_at(original, current + 1, 4,
                       ["HEIM","HOEK","HOLM","HOLZ"])) {
              primary   += "S";
              secondary += "S";
            } else {
              primary   += "X";
              secondary += "X";
            }
            current += 2;
            break;
          }

          // italian & armenian 
          if (string_at(original, current, 3,
                     ["SIO","SIA"])
              || string_at(original, current, 4,
                        ["SIAN"])) {
            if (!Slavo_Germanic(original)) {
              primary   += "S";
              secondary += "X";
            } else {
              primary   += "S";
              secondary += "S";
            }
            current += 3;
            break;
          }

          // german & anglicisations, e.g. 'smith' match 'schmidt', 'snider' match 'schneider'
          // also, -sz- in slavic language altho in hungarian it is pronounced 's'
          if (((current == 0)
               && string_at(original, current + 1, 1,
                         ["M","N","L","W"]))
              || string_at(original, current + 1, 1,
                        ["Z"])) {
            primary   += "S";
            secondary += "X";
            if (string_at(original, current + 1, 1,
                        ["Z"]))
              current += 2;
            else
              current += 1;
            break;
          }

          if (string_at(original, current, 2,
                     ["SC"])) {
            // Schlesinger's rule 
            if (original.substr(current + 2, 1) == 'H')
              // dutch origin, e.g. 'school', 'schooner'
              if (string_at(original, current + 3, 2,
                         ["OO","ER","EN","UY","ED","EM"])) {
                // 'schermerhorn', 'schenker' 
                if (string_at(original, current + 3, 2,
                           ["ER","EN"])) {
                  primary   += "X";
                  secondary += "SK";
                } else {
                  primary   += "SK";
                  secondary += "SK";
                }
                current += 3;
                break;
              } else {
                if ((current == 0) 
                    && !is_vowel(original, 3)
                    && (original.substr(current + 3, 1) != 'W')) {
                  primary   += "X";
                  secondary += "S";
                } else {
                  primary   += "X";
                  secondary += "X";
                }
                current += 3;
                break;
              }

              if (string_at(original, current + 2, 1,
                         ["I","E","Y"])) {
                primary   += "S";
                secondary += "S";
                current += 3;
                break;
              }

            // else
            primary   += "SK";
            secondary += "SK";
            current += 3;
            break;
          }

          // french e.g. 'resnais', 'artois'
          if ((current == last)
              && string_at(original, current - 2, 2,
                        ["AI","OI"])) {
            primary   += "";
            secondary += "S";
          } else {
            primary   += "S";
            secondary += "S";
          }

          if (string_at(original, current + 1, 1,
                     ["S","Z"]))
            current += 2;
          else 
            current += 1;
          break;

        case 'T':
          if (string_at(original, current, 4,
                     ["TION"])) {
            primary   += "X";
            secondary += "X";
            current += 3;
            break;
          }

          if (string_at(original, current, 3,
                     ["TIA","TCH"])) {
            primary   += "X";
            secondary += "X";
            current += 3;
            break;
          }

          if (string_at(original, current, 2,
                     ["TH"])
              || string_at(original, current, 3,
                            ["TTH"])) {
            // special case 'thomas', 'thames' or germanic
            if (string_at(original, current + 2, 2,
                       ["OM","AM"])
                || string_at(original, 0, 4, ["VAN ","VON "])
                || string_at(original, 0, 3, ["SCH"])) {
              primary   += "T";
              secondary += "T";
            } else {
              primary   += "0";
              secondary += "T";
            }
            current += 2;
            break;
          }

          if (string_at(original, current + 1, 1,
                     ["T","D"]))
            current += 2;
          else
            current += 1;
          primary   += "T";
          secondary += "T";
          break;

        case 'V':
          if (original.substr(current + 1, 1) == 'V')
            current += 2;
          else
            current += 1;
          primary   += "F";
          secondary += "F";
          break;

        case 'W':
          // can also be in middle of word
          if (string_at(original, current, 2, ["WR"])) {
            primary   += "R";
            secondary += "R";
            current += 2;
            break;
          }

          if ((current == 0)
              && (is_vowel(original, current + 1)
                  || string_at(original, current, 2, 
                            ["WH"]))) {
            // Wasserman should match Vasserman 
            if (is_vowel(original, current + 1)) {
              primary   += "A";
              secondary += "F";
            } else {
              // need Uomo to match Womo 
              primary   += "A";
              secondary += "A";
            }
          }

          // Arnow should match Arnoff
          if (((current == last) 
                && is_vowel(original, current - 1))
              || string_at(original, current - 1, 5,
                        ["EWSKI","EWSKY","OWSKI","OWSKY"])
              || string_at(original, 0, 3, ["SCH"])) {
            primary   += "";
            secondary += "F";
            current += 1;
            break;
          }

          // polish e.g. 'filipowicz'
          if (string_at(original, current, 4,
                     ["WICZ","WITZ"])) {
            primary   += "TS";
            secondary += "FX";
            current += 4;
            break;
          }

          // else skip it
          current += 1;
          break;

        case 'X':
          // french e.g. breaux 
          if (!((current == last)
                && (string_at(original, current - 3, 3,
                           ["IAU", "EAU"])
                 || string_at(original, current - 2, 2,
                           ["AU", "OU"])))) {
            primary   += "KS";
            secondary += "KS";
          }

          if (string_at(original, current + 1, 1,
                     ["C","X"]))
            current += 2;
          else
            current += 1;
          break;

        case 'Z':
          // chinese pinyin e.g. 'zhao' 
          if (original.substr(current + 1, 1) == "H") {
            primary   += "J";
            secondary += "J";
            current += 2;
            break;
          } else if (string_at(original, current + 1, 2,
                           ["ZO", "ZI", "ZA"])
                    || (Slavo_Germanic(original)
                        && ((current > 0)
                            && original.substr(current - 1, 1) != 'T'))) {
            primary   += "S";
            secondary += "TS";
          } else {
            primary   += "S";
            secondary += "S";
          }

          if (original.substr(current + 1, 1) == 'Z')
            current += 2;
          else
            current += 1;
          break;

        default:
          current += 1;

      } // end switch

    // printf("<br>ORIGINAL:    '%s'\n", original);
    // printf("<br>current:    '%s'\n", current);
    // printf("<br>  PRIMARY:   '%s'\n", primary);
    // printf("<br>  SECONDARY: '%s'\n", secondary);

    } // end while

    //primary   = primary.substr(  0, 12);
    //secondary = secondary.substr(0, 12);
    
    if( primary == secondary )
    {
      secondary = null ; 
    }
    
    return {
      primary: primary,
      secondary: secondary
    };
    
  } // end of function MetaPhone
  
  

function string_at(string, start, length, list) 
{
    if ((start <0) || (start >= string.length))
      return 0;

    for (var i=0, len=list.length; i<len; i++) {
      if (list[i] == string.substr(start, length))
        return 1;
    }
    return 0;
  }



function is_vowel(string, pos)
{
    return /[AEIOUY]/.test(string.substr(pos, 1));
}



function Slavo_Germanic(string) 
{
    return /W|K|CZ|WITZ/.test(string);     
}