/**

* Unobtrusive scripting adapter for jQuery
*
* Requires jQuery 1.6.0 or later.
* https://github.com/rails/jquery-ujs

* Uploading file using rails.js
* =============================
*
* By default, browsers do not allow files to be uploaded via AJAX. As a result, if there are any non-blank file fields
* in the remote form, this adapter aborts the AJAX submission and allows the form to submit through standard means.
*
* The `ajax:aborted:file` event allows you to bind your own handler to process the form submission however you wish.
*
* Ex:
*     $('form').live('ajax:aborted:file', function(event, elements){
*       // Implement own remote file-transfer handler here for non-blank file inputs passed in `elements`.
*       // Returning false in this handler tells rails.js to disallow standard form submission
*       return false;
*     });
*
* The `ajax:aborted:file` event is fired when a file-type input is detected with a non-blank value.
*
* Third-party tools can use this hook to detect when an AJAX file upload is attempted, and then use
* techniques like the iframe method to upload the file instead.
*
* Required fields in rails.js
* ===========================
*
* If any blank required inputs (required="required") are detected in the remote form, the whole form submission
* is canceled. Note that this is unlike file inputs, which still allow standard (non-AJAX) form submission.
*
* The `ajax:aborted:required` event allows you to bind your own handler to inform the user of blank required inputs.
*
* !! Note that Opera does not fire the form's submit event if there are blank required inputs, so this event may never
*    get fired in Opera. This event is what causes other browsers to exhibit the same submit-aborting behavior.
*
* Ex:
*     $('form').live('ajax:aborted:required', function(event, elements){
*       // Returning false in this handler tells rails.js to submit the form anyway.
*       // The blank required inputs are passed to this function in `elements`.
*       return ! confirm("Would you like to submit the form with missing info?");
*     });
*/

(function($, undefined) {

// Shorthand to make it a little easier to call public rails functions from within rails.js
var rails;

$.rails = rails = {
  // Link elements bound by jquery-ujs
  linkClickSelector: 'a[data-confirm], a[data-method], a[data-remote]',

              // Select elements bound by jquery-ujs
              selectChangeSelector: 'select[data-remote]',

  // Form elements bound by jquery-ujs
  formSubmitSelector: 'form',

  // Form input elements bound by jquery-ujs
  formInputClickSelector: 'form input[type=submit], form input[type=image], form button[type=submit], form button:not([type])',

  // Form input elements disabled during form submission
  disableSelector: 'input[data-disable-with], button[data-disable-with], textarea[data-disable-with]',

  // Form input elements re-enabled after form submission
  enableSelector: 'input[data-disable-with]:disabled, button[data-disable-with]:disabled, textarea[data-disable-with]:disabled',

  // Form required input elements
  requiredInputSelector: 'input[name][required]:not([disabled]),textarea[name][required]:not([disabled])',

  // Form file input elements
  fileInputSelector: 'input:file',

  // Make sure that every Ajax request sends the CSRF token
  CSRFProtection: function(xhr) {
    var token = $('meta[name="csrf-token"]').attr('content');
    if (token) xhr.setRequestHeader('X-CSRF-Token', token);
  },

  // Triggers an event on an element and returns false if the event result is false
  fire: function(obj, name, data) {
    var event = $.Event(name);
    obj.trigger(event, data);
    return event.result !== false;
  },

  // Default confirm dialog, may be overridden with custom confirm dialog in $.rails.confirm
  confirm: function(message) {
    return confirm(message);
  },

  // Default ajax function, may be overridden with custom function in $.rails.ajax
  ajax: function(options) {
    return $.ajax(options);
  },

  // Submits "remote" forms and links with ajax
  handleRemote: function(element) {
    var method, url, data,
      crossDomain = element.data('cross-domain') || null,
      dataType = element.data('type') || ($.ajaxSettings && $.ajaxSettings.dataType),
      options;

    if (rails.fire(element, 'ajax:before')) {

      if (element.is('form')) {
        method = element.attr('method');
        url = element.attr('action');
        data = element.serializeArray();
        // memoized value from clicked submit button
        var button = element.data('ujs:submit-button');
        if (button) {
          data.push(button);
          element.data('ujs:submit-button', null);
        }
      } else if (element.is('select')) {
        method = element.data('method');
        url = element.data('url');
        data = element.serialize();
        if (element.data('params')) data = data + "&" + element.data('params'); 
      } else {
         method = element.data('method');
         url = element.attr('href');
         data = element.data('params') || null; 
      }

      options = {
        type: method || 'GET', data: data, dataType: dataType, crossDomain: crossDomain,
        // stopping the "ajax:beforeSend" event will cancel the ajax request
        beforeSend: function(xhr, settings) {
          if (settings.dataType === undefined) {
            xhr.setRequestHeader('accept', '*/*;q=0.5, ' + settings.accepts.script);
          }
          return rails.fire(element, 'ajax:beforeSend', [xhr, settings]);
        },
        success: function(data, status, xhr) {
          element.trigger('ajax:success', [data, status, xhr]);
        },
        complete: function(xhr, status) {
          element.trigger('ajax:complete', [xhr, status]);
        },
        error: function(xhr, status, error) {
          element.trigger('ajax:error', [xhr, status, error]);
        }
      };
      // Only pass url to `ajax` options if not blank
      if (url) { options.url = url; }

      rails.ajax(options);
    }
  },

  // Handles "data-method" on links such as:
  // <a href="/users/5" data-method="delete" rel="nofollow" data-confirm="Are you sure?">Delete</a>
  handleMethod: function(link) {
    var href = link.attr('href'),
      method = link.data('method'),
      csrf_token = $('meta[name=csrf-token]').attr('content'),
      csrf_param = $('meta[name=csrf-param]').attr('content'),
      form = $('<form method="post" action="' + href + '"></form>'),
      metadata_input = '<input name="_method" value="' + method + '" type="hidden" />';

    if (csrf_param !== undefined && csrf_token !== undefined) {
      metadata_input += '<input name="' + csrf_param + '" value="' + csrf_token + '" type="hidden" />';
    }

    form.hide().append(metadata_input).appendTo('body');
    form.submit();
  },

  /* Disables form elements:
    - Caches element value in 'ujs:enable-with' data store
    - Replaces element text with value of 'data-disable-with' attribute
    - Adds disabled=disabled attribute
  */
  disableFormElements: function(form) {
    form.find(rails.disableSelector).each(function() {
      var element = $(this), method = element.is('button') ? 'html' : 'val';
      element.data('ujs:enable-with', element[method]());
      element[method](element.data('disable-with'));
      element.attr('disabled', 'disabled');
    });
  },

  /* Re-enables disabled form elements:
    - Replaces element text with cached value from 'ujs:enable-with' data store (created in `disableFormElements`)
    - Removes disabled attribute
  */
  enableFormElements: function(form) {
    form.find(rails.enableSelector).each(function() {
      var element = $(this), method = element.is('button') ? 'html' : 'val';
      if (element.data('ujs:enable-with')) element[method](element.data('ujs:enable-with'));
      element.removeAttr('disabled');
    });
  },

 /* For 'data-confirm' attribute:
    - Fires `confirm` event
    - Shows the confirmation dialog
    - Fires the `confirm:complete` event

    Returns `true` if no function stops the chain and user chose yes; `false` otherwise.
    Attaching a handler to the element's `confirm` event that returns a `falsy` value cancels the confirmation dialog.
    Attaching a handler to the element's `confirm:complete` event that returns a `falsy` value makes this function
    return false. The `confirm:complete` event is fired whether or not the user answered true or false to the dialog.
 */
  allowAction: function(element) {
    var message = element.data('confirm'),
        answer = false, callback;
    if (!message) { return true; }

    if (rails.fire(element, 'confirm')) {
      answer = rails.confirm(message);
      callback = rails.fire(element, 'confirm:complete', [answer]);
    }
    return answer && callback;
  },

  // Helper function which checks for blank inputs in a form that match the specified CSS selector
  blankInputs: function(form, specifiedSelector, nonBlank) {
    var inputs = $(), input,
      selector = specifiedSelector || 'input,textarea';
    form.find(selector).each(function() {
      input = $(this);
      // Collect non-blank inputs if nonBlank option is true, otherwise, collect blank inputs
      if (nonBlank ? input.val() : !input.val()) {
        inputs = inputs.add(input);
      }
    });
    return inputs.length ? inputs : false;
  },

  // Helper function which checks for non-blank inputs in a form that match the specified CSS selector
  nonBlankInputs: function(form, specifiedSelector) {
    return rails.blankInputs(form, specifiedSelector, true); // true specifies nonBlank
  },

  // Helper function, needed to provide consistent behavior in IE
  stopEverything: function(e) {
    $(e.target).trigger('ujs:everythingStopped');
    e.stopImmediatePropagation();
    return false;
  },

  // find all the submit events directly bound to the form and
  // manually invoke them. If anyone returns false then stop the loop
  callFormSubmitBindings: function(form) {
    var events = form.data('events'), continuePropagation = true;
    if (events !== undefined && events['submit'] !== undefined) {
      $.each(events['submit'], function(i, obj){
        if (typeof obj.handler === 'function') return continuePropagation = obj.handler(obj.data);
      });
    }
    return continuePropagation;
  }
};

$.ajaxPrefilter(function(options, originalOptions, xhr){ if ( !options.crossDomain ) { rails.CSRFProtection(xhr); }});

$(rails.linkClickSelector).live('click.rails', function(e) {
  var link = $(this);
  if (!rails.allowAction(link)) return rails.stopEverything(e);

  if (link.data('remote') !== undefined) {
    rails.handleRemote(link);
    return false;
  } else if (link.data('method')) {
    rails.handleMethod(link);
    return false;
  }
});

      $(rails.selectChangeSelector).live('change.rails', function(e) {
  var link = $(this);
  if (!rails.allowAction(link)) return rails.stopEverything(e);

  rails.handleRemote(link);
  return false;
});   

$(rails.formSubmitSelector).live('submit.rails', function(e) {
  var form = $(this),
    remote = form.data('remote') !== undefined,
    blankRequiredInputs = rails.blankInputs(form, rails.requiredInputSelector),
    nonBlankFileInputs = rails.nonBlankInputs(form, rails.fileInputSelector);

  if (!rails.allowAction(form)) return rails.stopEverything(e);

  // skip other logic when required values are missing or file upload is present
  if (blankRequiredInputs && form.attr("novalidate") == undefined && rails.fire(form, 'ajax:aborted:required', [blankRequiredInputs])) {
    return rails.stopEverything(e);
  }

  if (remote) {
    if (nonBlankFileInputs) {
      return rails.fire(form, 'ajax:aborted:file', [nonBlankFileInputs]);
    }

    // If browser does not support submit bubbling, then this live-binding will be called before direct
    // bindings. Therefore, we should directly call any direct bindings before remotely submitting form.
    if (!$.support.submitBubbles && rails.callFormSubmitBindings(form) === false) return rails.stopEverything(e);

    rails.handleRemote(form);
    return false;
  } else {
    // slight timeout so that the submit button gets properly serialized
    setTimeout(function(){ rails.disableFormElements(form); }, 13);
  }
});

$(rails.formInputClickSelector).live('click.rails', function(event) {
  var button = $(this);

  if (!rails.allowAction(button)) return rails.stopEverything(event);

  // register the pressed submit button
  var name = button.attr('name'),
    data = name ? {name:name, value:button.val()} : null;

  button.closest('form').data('ujs:submit-button', data);
});

$(rails.formSubmitSelector).live('ajax:beforeSend.rails', function(event) {
  if (this == event.target) rails.disableFormElements($(this));
});

$(rails.formSubmitSelector).live('ajax:complete.rails', function(event) {
  if (this == event.target) rails.enableFormElements($(this));
});

})( jQuery );