Javascript Random Password Generator (jQuery)

passwdgen.js

// Demo: http://jsbin.com/emisib/5/edit#preview
//
// Markup:
//
//   <input type="text" name="password" id="password" />
//   <a href="#" class="passworder" data-length="10" data-target="#password">Generate</a>
//
// - vjt@openssl.it - public domain
//
(function () {
  var rand = function (str) {
    return str[Math.floor (Math.random () * str.length)];
  };

  var get = function (source, len, a) {
    for (var i = 0; i < len; i++)
      a.push (rand (source));
    return a;
  };

  var alpha  = function (len, a) {
    return get ("A1BCD2EFG3HIJ4KLM5NOP6QRS7TUV8WXY9Z", len, a);
  };
  var symbol = function (len, a) {
    return get ("-:;_$!", len, a);
  };

  $('.passworder').live ('click', function (event) {
    event.preventDefault ();

    var widget = $(this);
    var target = $(widget.data ('target'));

    var length = widget.data ('length') - 1;

    // Alpha{ceil((length-1)/2))} Symbol Alpha{floor((length-1)/(2))}
    var l = Math.floor (length/2), r = Math.ceil (length/2);
    var ret = alpha (l, symbol (1, alpha (r, []))).join('');

    target.val (ret);
  });
}) ();