/*
---
name: Form.RadioGroup
description: Class to represent a group of Form.Radio buttons
authors: Bryan J Swift (@bryanjswift)
license: MIT-style license.
requires: [Core/Class.Extras, Core/Element, Core/Element.Event, Form-Replacement/Form.Radio]
provides: Form.RadioGroup
...
*/
if (typeof window.Form === 'undefined') { window.Form = {}; }

Form.RadioGroup = new Class({
  Implements: [Events,Options],
  options: {
    radioOptions: {},
    initialValues: {}
  },
  bound: {},
  radios: [],
  value: null,
  initialize: function(group,options) {
    if (!Form.Radio) { throw 'required Class Form.Radio not found'; }
    this.setOptions(options);
    this.bound = { select: this.select.bind(this) };
    group = $(group);
    if (!group) { return this; }
    var radios = group.getElements('input[type=radio]');
    radios.each(this.addCheck,this);
  },
  addCheck: function(radio,i) {
    var initialValues = this.options.initialValues[radio.get('name')];
    var radioOptions = {};
    radioOptions.checked = initialValues ? initialValues.contains(radio.get('value')) : radio.get('checked');
    radioOptions.disabled = radio.get('disabled');
    var check = (radio.retrieve('Form.Radio::data')
                 || new Form.Radio(radio,Object.append(radioOptions,this.options.radioOptions)));
    check.addEvent('onCheck',this.bound.select);
    if (check.checked) { i ? this.changed(check) : this.value = check.value; }
    radio.store('Form.RadioGroup::data',this);
    this.radios.push(check);
  },
  changed: function(radio) {
    this.value = radio.value;
    this.fireEvent('onChange',this);
  },
  disable: function() {
    this.radios.each(function(radio) { radio.disable(); });
  },
  enable: function() {
    this.radios.each(function(radio) { radio.enable(); });
  },
  select: function(checkedRadio) {
    this.radios.each(function(radio) {
      if (radio.checked && radio.value !== checkedRadio.value) { radio.uncheck(); }
    });
    if (checkedRadio.value !== this.value) { this.changed(checkedRadio); }
  }
});