SemanSemantic-UItic-UI/dist/components/form.js

/*
 * # Semantic - Form Validation
 * http://github.com/semantic-org/semantic-ui/
 *
 *
 * Copyright 2014 Contributor
 * Released under the MIT license
 * http://opensource.org/licenses/MIT
 *
 */

;(function ( $, window, document, undefined ) {

$.fn.form = function(fields, parameters) {
  var
    $allModules     = $(this),

    settings        = $.extend(true, {}, $.fn.form.settings, parameters),
    validation      = $.extend({}, $.fn.form.settings.defaults, fields),

    namespace       = settings.namespace,
    metadata        = settings.metadata,
    selector        = settings.selector,
    className       = settings.className,
    error           = settings.error,

    eventNamespace  = '.' + namespace,
    moduleNamespace = 'module-' + namespace,

    moduleSelector  = $allModules.selector || '',

    time            = new Date().getTime(),
    performance     = [],

    query           = arguments[0],
    methodInvoked   = (typeof query == 'string'),
    queryArguments  = [].slice.call(arguments, 1),
    returnedValue
  ;
  $allModules
    .each(function() {
      var
        $module     = $(this),
        $field      = $(this).find(selector.field),
        $group      = $(this).find(selector.group),
        $message    = $(this).find(selector.message),
        $prompt     = $(this).find(selector.prompt),

        $submit     = $(this).find(selector.submit),
        $clear      = $(this).find(selector.clear),
        $reset      = $(this).find(selector.reset),

        formErrors  = [],
        keyHeldDown = false,

        element     = this,
        instance    = $module.data(moduleNamespace),
        module
      ;

      module      = {

        initialize: function() {
          module.verbose('Initializing form validation', $module, validation, settings);
          module.bindEvents();
          module.set.defaults();
          module.instantiate();
        },

        instantiate: function() {
          module.verbose('Storing instance of module', module);
          instance = module;
          $module
            .data(moduleNamespace, module)
          ;
        },

        destroy: function() {
          module.verbose('Destroying previous module', instance);
          module.removeEvents();
          $module
            .removeData(moduleNamespace)
          ;
        },

        refresh: function() {
          module.verbose('Refreshing selector cache');
          $field = $module.find(selector.field);
        },

        submit: function() {
          module.verbose('Submitting form', $module);
          $module
            .submit()
          ;
        },

        attachEvents: function(selector, action) {
          action = action || 'submit';
          $(selector)
            .on('click', function(event) {
              module[action]();
              event.preventDefault();
            })
          ;
        },

        bindEvents: function() {
          if(settings.keyboardShortcuts) {
            $field
              .on('keydown' + eventNamespace, module.event.field.keydown)
            ;
          }
          $module
            .on('submit' + eventNamespace, module.validate.form)
          ;
          $field
            .on('blur' + eventNamespace, module.event.field.blur)
          ;

          // attach events to common elements
          module.attachEvents($submit, 'submit');
          module.attachEvents($reset, 'reset');
          module.attachEvents($clear, 'clear');

          $field
            .each(function() {
              var
                type       = $(this).prop('type'),
                inputEvent = module.get.changeEvent(type)
              ;
              $(this)
                .on(inputEvent + eventNamespace, module.event.field.change)
              ;
            })
          ;
        },

        clear: function() {
          $field
            .each(function () {
              var
                $field       = $(this),
                $element     = $field.parent(),
                $fieldGroup  = $field.closest($group),
                $prompt      = $fieldGroup.find(selector.prompt),
                defaultValue = $field.data(metadata.defaultValue) || '',
                isCheckbox   = $element.is(selector.uiCheckbox),
                isDropdown   = $element.is(selector.uiDropdown),
                isErrored    = $fieldGroup.hasClass(className.error)
              ;
              if(isErrored) {
                module.verbose('Resetting error on field', $fieldGroup);
                $fieldGroup.removeClass(className.error);
                $prompt.remove();
              }
              if(isDropdown) {
                module.verbose('Resetting dropdown value', $element, defaultValue);
                $element.dropdown('clear');
              }
              else if(isCheckbox) {
                $element.checkbox('uncheck');
              }
              else {
                module.verbose('Resetting field value', $field, defaultValue);
                $field.val('');
              }
            })
          ;
        },

        reset: function() {
          $field
            .each(function () {
              var
                $field       = $(this),
                $element     = $field.parent(),
                $fieldGroup  = $field.closest($group),
                $prompt      = $fieldGroup.find(selector.prompt),
                defaultValue = $field.data(metadata.defaultValue) || '',
                isCheckbox   = $element.is(selector.uiCheckbox),
                isDropdown   = $element.is(selector.uiDropdown),
                isErrored    = $fieldGroup.hasClass(className.error)
              ;
              if(isErrored) {
                module.verbose('Resetting error on field', $fieldGroup);
                $fieldGroup.removeClass(className.error);
                $prompt.remove();
              }
              if(isDropdown) {
                module.verbose('Resetting dropdown value', $element, defaultValue);
                $element.dropdown('restore defaults');
              }
              else if(isCheckbox) {
                module.verbose('Resetting checkbox value', $element, defaultValue);
                if(defaultValue === true) {
                  $element.checkbox('check');
                }
                else {
                  $element.checkbox('uncheck');
                }
              }
              else {
                module.verbose('Resetting field value', $field, defaultValue);
                $field.val(defaultValue);
              }
            })
          ;
        },

        removeEvents: function() {
          $module
            .off(eventNamespace)
          ;
          $field
            .off(eventNamespace)
          ;
          $submit
            .off(eventNamespace)
          ;
          $field
            .off(eventNamespace)
          ;
        },

        event: {
          field: {
            keydown: function(event) {
              var
                $field  = $(this),
                key     = event.which,
                keyCode = {
                  enter  : 13,
                  escape : 27
                }
              ;
              if( key == keyCode.escape) {
                module.verbose('Escape key pressed blurring field');
                $field
                  .blur()
                ;
              }
              if(!event.ctrlKey && key == keyCode.enter && $field.is(selector.input) && $field.not(selector.checkbox).length > 0 ) {
                $submit
                  .addClass(className.pressed)
                ;
                if(!keyHeldDown) {
                  $field
                    .one('keyup' + eventNamespace, module.event.field.keyup)
                  ;
                  module.submit();
                  module.debug('Enter pressed on input submitting form');
                }
                keyHeldDown = true;
              }
            },
            keyup: function() {
              keyHeldDown = false;
              $submit.removeClass(className.pressed);
            },
            blur: function() {
              var
                $field      = $(this),
                $fieldGroup = $field.closest($group)
              ;
              if( $fieldGroup.hasClass(className.error) ) {
                module.debug('Revalidating field', $field,  module.get.validation($field));
                module.validate.field( module.get.validation($field) );
              }
              else if(settings.on == 'blur' || settings.on == 'change') {
                module.validate.field( module.get.validation($field) );
              }
            },
            change: function() {
              var
                $field      = $(this),
                $fieldGroup = $field.closest($group)
              ;
              if(settings.on == 'change' || ( $fieldGroup.hasClass(className.error) && settings.revalidate) ) {
                clearTimeout(module.timer);
                module.timer = setTimeout(function() {
                  module.debug('Revalidating field', $field,  module.get.validation($field));
                  module.validate.field( module.get.validation($field) );
                }, settings.delay);
              }
            }
          }

        },

        get: {
          changeEvent: function(type) {
            if(type == 'checkbox' || type == 'radio' || type == 'hidden') {
              return 'change';
            }
            else {
              return module.get.inputEvent();
            }
          },
          inputEvent: function() {
            return (document.createElement('input').oninput !== undefined)
              ? 'input'
              : (document.createElement('input').onpropertychange !== undefined)
                ? 'propertychange'
                : 'keyup'
            ;
          },
          field: function(identifier) {
            module.verbose('Finding field with identifier', identifier);
            if( $field.filter('#' + identifier).length > 0 ) {
              return $field.filter('#' + identifier);
            }
            else if( $field.filter('[name="' + identifier +'"]').length > 0 ) {
              return $field.filter('[name="' + identifier +'"]');
            }
            else if( $field.filter('[data-' + metadata.validate + '="'+ identifier +'"]').length > 0 ) {
              return $field.filter('[data-' + metadata.validate + '="'+ identifier +'"]');
            }
            return $('<input/>');
          },
          validation: function($field) {
            var
              rules
            ;
            $.each(validation, function(fieldName, field) {
              if( module.get.field(field.identifier).get(0) == $field.get(0) ) {
                rules = field;
              }
            });
            return rules || false;
          },
          value: function (field) {
            var
              fields = [],
              results
            ;
            fields.push(field);
            results = module.get.values.call(element, fields);
            return results[field];
          },
          values: function (fields) {
            var
              values = {}
            ;
            // return all fields if no parameters
            if(!$.isArray(fields)) {
              fields = $field;
            }
            $.each(fields, function(index, field) {
              var
                $field     = (typeof field === 'string')
                  ? module.get.field(field)
                  : $(field),
                type       = $field.prop('type'),
                name       = $field.prop('name'),
                value      = $field.val(),
                isCheckbox = $field.is(selector.checkbox),
                isRadio    = $field.is(selector.radio),
                isChecked  = (isCheckbox)
                  ? $field.is(':checked')
                  : false
              ;
              if(name) {
                if(isRadio) {
                  if(isChecked) {
                    values[name] = value;
                  }
                }
                else if(isCheckbox) {
                  if(isChecked) {
                    values[name] = true;
                  }
                  else {
                    module.debug('Omitted unchecked checkbox', $field);
                    return true;
                  }
                }
                else {
                  values[name] = value;
                }
              }
            });
            return values;
          }
        },

        has: {

          field: function(identifier) {
            module.verbose('Checking for existence of a field with identifier', identifier);
            if( $field.filter('#' + identifier).length > 0 ) {
              return true;
            }
            else if( $field.filter('[name="' + identifier +'"]').length > 0 ) {
              return true;
            }
            else if( $field.filter('[data-' + metadata.validate + '="'+ identifier +'"]').length > 0 ) {
              return true;
            }
            return false;
          }

        },

        add: {
          prompt: function(identifier, errors) {
            var
              $field       = module.get.field(identifier),
              $fieldGroup  = $field.closest($group),
              $prompt      = $fieldGroup.children(selector.prompt),
              promptExists = ($prompt.length !== 0)
            ;
            errors = (typeof errors == 'string')
              ? [errors]
              : errors
            ;
            module.verbose('Adding field error state', identifier);
            $fieldGroup
              .addClass(className.error)
            ;
            if(settings.inline) {
              if(!promptExists) {
                $prompt = settings.templates.prompt(errors);
                $prompt
                  .appendTo($fieldGroup)
                ;
              }
              $prompt
                .html(errors[0])
              ;
              if(!promptExists) {
                if(settings.transition && $.fn.transition !== undefined && $module.transition('is supported')) {
                  module.verbose('Displaying error with css transition', settings.transition);
                  $prompt.transition(settings.transition + ' in', settings.duration);
                }
                else {
                  module.verbose('Displaying error with fallback javascript animation');
                  $prompt
                    .fadeIn(settings.duration)
                  ;
                }
              }
              else {
                module.verbose('Inline errors are disabled, no inline error added', identifier);
              }
            }
          },
          errors: function(errors) {
            module.debug('Adding form error messages', errors);
            $message
              .html( settings.templates.error(errors) )
            ;
          }
        },

        remove: {
          prompt: function(field) {
            var
              $field      = module.get.field(field.identifier),
              $fieldGroup = $field.closest($group),
              $prompt     = $fieldGroup.children(selector.prompt)
            ;
            $fieldGroup
              .removeClass(className.error)
            ;
            if(settings.inline && $prompt.is(':visible')) {
              module.verbose('Removing prompt for field', field);
              if(settings.transition && $.fn.transition !== undefined && $module.transition('is supported')) {
                $prompt.transition(settings.transition + ' out', settings.duration, function() {
                  $prompt.remove();
                });
              }
              else {
                $prompt
                  .fadeOut(settings.duration, function(){
                    $prompt.remove();
                  })
                ;
              }
            }
          }
        },

        set: {
          success: function() {
            $module
              .removeClass(className.error)
              .addClass(className.success)
            ;
          },
          defaults: function () {
            $field
              .each(function () {
                var
                  $field     = $(this),
                  isCheckbox = ($field.filter(selector.checkbox).length > 0),
                  value      = (isCheckbox)
                    ? $field.is(':checked')
                    : $field.val()
                ;
                $field.data(metadata.defaultValue, value);
              })
            ;
          },
          error: function() {
            $module
              .removeClass(className.success)
              .addClass(className.error)
            ;
          },
          value: function (field, value) {
            var
              fields = {}
            ;
            fields[field] = value;
            return module.set.values.call(element, fields);
          },
          values: function (fields) {
            if($.isEmptyObject(fields)) {
              return;
            }
            $.each(fields, function(key, value) {
              var
                $field      = module.get.field(key),
                $element    = $field.parent(),
                isCheckbox  = $element.is(selector.uiCheckbox),
                isDropdown  = $element.is(selector.uiDropdown),
                isRadio     = $field.is(selector.radio),
                fieldExists = ($field.length > 0)
              ;
              if(fieldExists) {
                if(isRadio && isCheckbox) {
                  module.verbose('Selecting radio value', value, $field);
                  $field.filter('[value="' + value + '"]')
                    .parent(selector.uiCheckbox)
                      .checkbox('check')
                  ;
                }
                else if(isCheckbox) {
                  module.verbose('Setting checkbox value', value, $element);
                  if(value === true) {
                    $element.checkbox('check');
                  }
                  else {
                    $element.checkbox('uncheck');
                  }
                }
                else if(isDropdown) {
                  module.verbose('Setting dropdown value', value, $element);
                  $element.dropdown('set selected', value);
                }
                else {
                  module.verbose('Setting field value', value, $field);
                  $field.val(value);
                }
              }
            });
            module.validate.form();
          }
        },

        validate: {

          form: function(event) {
            var
              allValid = true,
              apiRequest
            ;

            // input keydown event will fire submit repeatedly by browser default
            if(keyHeldDown) {
              return false;
            }

            // reset errors
            formErrors = [];
            $.each(validation, function(fieldName, field) {
              if( !( module.validate.field(field) ) ) {
                allValid = false;
              }
            });
            if(allValid) {
              module.debug('Form has no validation errors, submitting');
              module.set.success();
              return settings.onSuccess.call(element, event);
            }
            else {
              module.debug('Form has errors');
              module.set.error();
              if(!settings.inline) {
                module.add.errors(formErrors);
              }
              // prevent ajax submit
              if($module.data('moduleApi') !== undefined) {
                event.stopImmediatePropagation();
              }
              return settings.onFailure.call(element, formErrors);
            }
          },

          // takes a validation object and returns whether field passes validation
          field: function(field) {
            var
              $field      = module.get.field(field.identifier),
              fieldValid  = true,
              fieldErrors = []
            ;
            if($field.prop('disabled')) {
              module.debug('Field is disabled. Skipping', field.identifier);
              fieldValid = true;
            }
            else if(field.optional && $.trim($field.val()) === ''){
              module.debug('Field is optional and empty. Skipping', field.identifier);
              fieldValid = true;
            }
            else if(field.rules !== undefined) {
              $.each(field.rules, function(index, rule) {
                if( module.has.field(field.identifier) && !( module.validate.rule(field, rule) ) ) {
                  module.debug('Field is invalid', field.identifier, rule.type);
                  fieldErrors.push(rule.prompt);
                  fieldValid = false;
                }
              });
            }
            if(fieldValid) {
              module.remove.prompt(field, fieldErrors);
              settings.onValid.call($field);
            }
            else {
              formErrors = formErrors.concat(fieldErrors);
              module.add.prompt(field.identifier, fieldErrors);
              settings.onInvalid.call($field, fieldErrors);
              return false;
            }
            return true;
          },

          // takes validation rule and returns whether field passes rule
          rule: function(field, validation) {
            var
              $field        = module.get.field(field.identifier),
              type          = validation.type,
              value         = $.trim($field.val() + ''),

              bracketRegExp = /\[(.*)\]/i,
              bracket       = bracketRegExp.exec(type),
              isValid       = true,
              ancillary,
              functionType
            ;
            // if bracket notation is used, pass in extra parameters
            if(bracket !== undefined && bracket !== null) {
              ancillary    = '' + bracket[1];
              functionType = type.replace(bracket[0], '');
              isValid      = settings.rules[functionType].call(element, value, ancillary);
            }
            // normal notation
            else {
              isValid = settings.rules[type].call($field, value);
            }
            return isValid;
          }
        },

        setting: function(name, value) {
          if( $.isPlainObject(name) ) {
            $.extend(true, settings, name);
          }
          else if(value !== undefined) {
            settings[name] = value;
          }
          else {
            return settings[name];
          }
        },
        internal: function(name, value) {
          if( $.isPlainObject(name) ) {
            $.extend(true, module, name);
          }
          else if(value !== undefined) {
            module[name] = value;
          }
          else {
            return module[name];
          }
        },
        debug: function() {
          if(settings.debug) {
            if(settings.performance) {
              module.performance.log(arguments);
            }
            else {
              module.debug = Function.prototype.bind.call(console.info, console, settings.name + ':');
              module.debug.apply(console, arguments);
            }
          }
        },
        verbose: function() {
          if(settings.verbose && settings.debug) {
            if(settings.performance) {
              module.performance.log(arguments);
            }
            else {
              module.verbose = Function.prototype.bind.call(console.info, console, settings.name + ':');
              module.verbose.apply(console, arguments);
            }
          }
        },
        error: function() {
          module.error = Function.prototype.bind.call(console.error, console, settings.name + ':');
          module.error.apply(console, arguments);
        },
        performance: {
          log: function(message) {
            var
              currentTime,
              executionTime,
              previousTime
            ;
            if(settings.performance) {
              currentTime   = new Date().getTime();
              previousTime  = time || currentTime;
              executionTime = currentTime - previousTime;
              time          = currentTime;
              performance.push({
                'Name'           : message[0],
                'Arguments'      : [].slice.call(message, 1) || '',
                'Element'        : element,
                'Execution Time' : executionTime
              });
            }
            clearTimeout(module.performance.timer);
            module.performance.timer = setTimeout(module.performance.display, 100);
          },
          display: function() {
            var
              title = settings.name + ':',
              totalTime = 0
            ;
            time = false;
            clearTimeout(module.performance.timer);
            $.each(performance, function(index, data) {
              totalTime += data['Execution Time'];
            });
            title += ' ' + totalTime + 'ms';
            if(moduleSelector) {
              title += ' \'' + moduleSelector + '\'';
            }
            if($allModules.length > 1) {
              title += ' ' + '(' + $allModules.length + ')';
            }
            if( (console.group !== undefined || console.table !== undefined) && performance.length > 0) {
              console.groupCollapsed(title);
              if(console.table) {
                console.table(performance);
              }
              else {
                $.each(performance, function(index, data) {
                  console.log(data['Name'] + ': ' + data['Execution Time']+'ms');
                });
              }
              console.groupEnd();
            }
            performance = [];
          }
        },
        invoke: function(query, passedArguments, context) {
          var
            object = instance,
            maxDepth,
            found,
            response
          ;
          passedArguments = passedArguments || queryArguments;
          context         = element         || context;
          if(typeof query == 'string' && object !== undefined) {
            query    = query.split(/[\. ]/);
            maxDepth = query.length - 1;
            $.each(query, function(depth, value) {
              var camelCaseValue = (depth != maxDepth)
                ? value + query[depth + 1].charAt(0).toUpperCase() + query[depth + 1].slice(1)
                : query
              ;
              if( $.isPlainObject( object[camelCaseValue] ) && (depth != maxDepth) ) {
                object = object[camelCaseValue];
              }
              else if( object[camelCaseValue] !== undefined ) {
                found = object[camelCaseValue];
                return false;
              }
              else if( $.isPlainObject( object[value] ) && (depth != maxDepth) ) {
                object = object[value];
              }
              else if( object[value] !== undefined ) {
                found = object[value];
                return false;
              }
              else {
                return false;
              }
            });
          }
          if( $.isFunction( found ) ) {
            response = found.apply(context, passedArguments);
          }
          else if(found !== undefined) {
            response = found;
          }
          if($.isArray(returnedValue)) {
            returnedValue.push(response);
          }
          else if(returnedValue !== undefined) {
            returnedValue = [returnedValue, response];
          }
          else if(response !== undefined) {
            returnedValue = response;
          }
          return found;
        }
      };
      if(methodInvoked) {
        if(instance === undefined) {
          module.initialize();
        }
        module.invoke(query);
      }
      else {
        if(instance !== undefined) {
          module.destroy();
        }
        module.initialize();
      }

    })
  ;

  return (returnedValue !== undefined)
    ? returnedValue
    : this
  ;
};

$.fn.form.settings = {

  name              : 'Form',
  namespace         : 'form',

  debug             : false,
  verbose           : true,
  performance       : true,


  keyboardShortcuts : true,
  on                : 'submit',
  inline            : false,

  delay             : 200,
  revalidate        : true,

  transition        : 'scale',
  duration          : 200,

  onValid           : function() {},
  onInvalid         : function() {},
  onSuccess         : function() { return true; },
  onFailure         : function() { return false; },

  metadata : {
    defaultValue : 'default',
    validate     : 'validate'
  },

  selector : {
    checkbox   : 'input[type="checkbox"], input[type="radio"]',
    clear      : '.clear',
    field      : 'input, textarea, select',
    group      : '.field',
    input      : 'input',
    message    : '.error.message',
    prompt     : '.prompt.label',
    radio      : 'input[type="radio"]',
    reset      : '.reset',
    submit     : '.submit',
    uiCheckbox : '.ui.checkbox',
    uiDropdown : '.ui.dropdown'
  },

  className : {
    error   : 'error',
    label   : 'ui prompt label',
    pressed : 'down',
    success : 'success'
  },

  error: {
    method   : 'The method you called is not defined.'
  },

  templates: {

    // template that produces error message
    error: function(errors) {
      var
        html = '<ul class="list">'
      ;
      $.each(errors, function(index, value) {
        html += '<li>' + value + '</li>';
      });
      html += '</ul>';
      return $(html);
    },

    // template that produces label
    prompt: function(errors) {
      return $('<div/>')
        .addClass('ui red pointing prompt label')
        .html(errors[0])
      ;
    }
  },

  rules: {

    // checkbox checked
    checked: function() {
      return ($(this).filter(':checked').length > 0);
    },

    // value contains (text)
    contains: function(value, text) {
      text = text.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&");
      return (value.search(text) !== -1);
    },

    // is most likely an email
    email: function(value){
      var
        emailRegExp = new RegExp("[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?", "i")
      ;
      return emailRegExp.test(value);
    },

    // is not empty or blank string
    empty: function(value) {
      return !(value === undefined || '' === value);
    },

    // is valid integer
    integer: function(value, range) {
      var
        intRegExp = /^\-?\d+$/,
        min,
        max,
        parts
      ;
      if(range === undefined || range === '' || range === '..') {
        // do nothing
      }
      else if(range.indexOf('..') == -1) {
        if(intRegExp.test(range)) {
          min = max = range - 0;
        }
      }
      else {
        parts = range.split('..', 2);
        if(intRegExp.test(parts[0])) {
          min = parts[0] - 0;
        }
        if(intRegExp.test(parts[1])) {
          max = parts[1] - 0;
        }
      }
      return (
        intRegExp.test(value) &&
        (min === undefined || value >= min) &&
        (max === undefined || value <= max)
      );
    },

    // is exactly value
    is: function(value, text) {
      return (value == text);
    },

    // is at least string length
    length: function(value, requiredLength) {
      return (value !== undefined)
        ? (value.length >= requiredLength)
        : false
      ;
    },

    // matches another field
    match: function(value, fieldIdentifier) {
      // use either id or name of field
      var
        $form = $(this),
        matchingValue
      ;
      if($form.find('#' + fieldIdentifier).length > 0) {
        matchingValue = $form.find('#' + fieldIdentifier).val();
      }
      else if($form.find('[name="' + fieldIdentifier +'"]').length > 0) {
        matchingValue = $form.find('[name="' + fieldIdentifier + '"]').val();
      }
      else if( $form.find('[data-validate="'+ fieldIdentifier +'"]').length > 0 ) {
        matchingValue = $form.find('[data-validate="'+ fieldIdentifier +'"]').val();
      }
      return (matchingValue !== undefined)
        ? ( value.toString() == matchingValue.toString() )
        : false
      ;
    },

    // string length is less than max length
    maxLength: function(value, maxLength) {
      return (value !== undefined)
        ? (value.length <= maxLength)
        : false
      ;
    },

    // value is not exactly notValue
    not: function(value, notValue) {
      return (value != notValue);
    },

    // value is most likely url
    url: function(value) {
      var
        urlRegExp = /(ftp|http|https):\/\/(\w+:{0,1}\w*@)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%@!\-\/]))?/
      ;
      return urlRegExp.test(value);
    }
  }

};

})( jQuery, window , document );