(function (factory) {
  'use strict';
  if (typeof define === 'function' && define.amd) {
      // Register as an anonymous AMD module:
      define(['jquery'], factory);
  } else if (typeof exports === 'object') {
      // Node/CommonJS:
      factory(require('jquery'));
  } else {
      // Browser globals:
      factory(window.jQuery);
  }
}(function ($) {
  'use strict';

  // Helper variable to create unique names for the transport iframes:
  var counter = 0,
      jsonAPI = $,
      jsonParse = 'parseJSON';

  if ('JSON' in window && 'parse' in JSON) {
    jsonAPI = JSON;
    jsonParse = 'parse';
  }

  // The iframe transport accepts four additional options:
  // options.fileInput: a jQuery collection of file input fields
  // options.paramName: the parameter name for the file form data,
  //  overrides the name property of the file input field(s),
  //  can be a string or an array of strings.
  // options.formData: an array of objects with name and value properties,
  //  equivalent to the return data of .serializeArray(), e.g.:
  //  [{name: 'a', value: 1}, {name: 'b', value: 2}]
  // options.initialIframeSrc: the URL of the initial iframe src,
  //  by default set to "javascript:false;"
  $.ajaxTransport('iframe', function (options) {
      if (options.async) {
          // javascript:false as initial iframe src
          // prevents warning popups on HTTPS in IE6:
          /*jshint scripturl: true */
          var initialIframeSrc = options.initialIframeSrc || 'javascript:false;',
          /*jshint scripturl: false */
              form,
              iframe,
              addParamChar;
          return {
              send: function (_, completeCallback) {
                  form = $('<form style="display:none;"></form>');
                  form.attr('accept-charset', options.formAcceptCharset);
                  addParamChar = /\?/.test(options.url) ? '&' : '?';
                  // XDomainRequest only supports GET and POST:
                  if (options.type === 'DELETE') {
                      options.url = options.url + addParamChar + '_method=DELETE';
                      options.type = 'POST';
                  } else if (options.type === 'PUT') {
                      options.url = options.url + addParamChar + '_method=PUT';
                      options.type = 'POST';
                  } else if (options.type === 'PATCH') {
                      options.url = options.url + addParamChar + '_method=PATCH';
                      options.type = 'POST';
                  }
                  // IE versions below IE8 cannot set the name property of
                  // elements that have already been added to the DOM,
                  // so we set the name along with the iframe HTML markup:
                  counter += 1;
                  iframe = $(
                      '<iframe src="' + initialIframeSrc +
                          '" name="iframe-transport-' + counter + '"></iframe>'
                  ).bind('load', function () {
                      var fileInputClones,
                          paramNames = $.isArray(options.paramName) ?
                                  options.paramName : [options.paramName];
                      iframe
                          .unbind('load')
                          .bind('load', function () {
                              var response;
                              // Wrap in a try/catch block to catch exceptions thrown
                              // when trying to access cross-domain iframe contents:
                              try {
                                  response = iframe.contents();
                                  // Google Chrome and Firefox do not throw an
                                  // exception when calling iframe.contents() on
                                  // cross-domain requests, so we unify the response:
                                  if (!response.length || !response[0].firstChild) {
                                      throw new Error();
                                  }
                              } catch (e) {
                                  response = undefined;
                              }
                              // The complete callback returns the
                              // iframe content document as response object:
                              completeCallback(
                                  200,
                                  'success',
                                  {'iframe': response}
                              );
                              // Fix for IE endless progress bar activity bug
                              // (happens on form submits to iframe targets):
                              $('<iframe src="' + initialIframeSrc + '"></iframe>')
                                  .appendTo(form);
                              window.setTimeout(function () {
                                  // Removing the form in a setTimeout call
                                  // allows Chrome's developer tools to display
                                  // the response result
                                  form.remove();
                              }, 0);
                          });
                      form
                          .prop('target', iframe.prop('name'))
                          .prop('action', options.url)
                          .prop('method', options.type);
                      if (options.formData) {
                          $.each(options.formData, function (index, field) {
                              $('<input type="hidden"/>')
                                  .prop('name', field.name)
                                  .val(field.value)
                                  .appendTo(form);
                          });
                      }
                      if (options.fileInput && options.fileInput.length &&
                              options.type === 'POST') {
                          fileInputClones = options.fileInput.clone();
                          // Insert a clone for each file input field:
                          options.fileInput.after(function (index) {
                              return fileInputClones[index];
                          });
                          if (options.paramName) {
                              options.fileInput.each(function (index) {
                                  $(this).prop(
                                      'name',
                                      paramNames[index] || options.paramName
                                  );
                              });
                          }
                          // Appending the file input fields to the hidden form
                          // removes them from their original location:
                          form
                              .append(options.fileInput)
                              .prop('enctype', 'multipart/form-data')
                              // enctype must be set as encoding for IE:
                              .prop('encoding', 'multipart/form-data');
                          // Remove the HTML5 form attribute from the input(s):
                          options.fileInput.removeAttr('form');
                      }
                      form.submit();
                      // Insert the file input fields at their original location
                      // by replacing the clones with the originals:
                      if (fileInputClones && fileInputClones.length) {
                          options.fileInput.each(function (index, input) {
                              var clone = $(fileInputClones[index]);
                              // Restore the original name and form properties:
                              $(input)
                                  .prop('name', clone.prop('name'))
                                  .attr('form', clone.attr('form'));
                              clone.replaceWith(input);
                          });
                      }
                  });
                  form.append(iframe).appendTo(document.body);
              },
              abort: function () {
                  if (iframe) {
                      // javascript:false as iframe src aborts the request
                      // and prevents warning popups on HTTPS in IE6.
                      // concat is used to avoid the "Script URL" JSLint error:
                      iframe
                          .unbind('load')
                          .prop('src', initialIframeSrc);
                  }
                  if (form) {
                      form.remove();
                  }
              }
          };
      }
  });

  // The iframe transport returns the iframe content document as response.
  // The following adds converters from iframe to text, json, html, xml
  // and script.
  // Please note that the Content-Type for JSON responses has to be text/plain
  // or text/html, if the browser doesn't include application/json in the
  // Accept header, else IE will show a download dialog.
  // The Content-Type for XML responses on the other hand has to be always
  // application/xml or text/xml, so IE properly parses the XML response.
  // See also
  // https://github.com/blueimp/jQuery-File-Upload/wiki/Setup#content-type-negotiation
  $.ajaxSetup({
      converters: {
          'iframe text': function (iframe) {
              return iframe && $(iframe[0].body).text();
          },
          'iframe json': function (iframe) {
              return iframe && jsonAPI[jsonParse]($(iframe[0].body).text());
          },
          'iframe html': function (iframe) {
              return iframe && $(iframe[0].body).html();
          },
          'iframe xml': function (iframe) {
              var xmlDoc = iframe && iframe[0];
              return xmlDoc && $.isXMLDoc(xmlDoc) ? xmlDoc :
                      $.parseXML((xmlDoc.XMLDocument && xmlDoc.XMLDocument.xml) ||
                          $(xmlDoc.body).html());
          },
          'iframe script': function (iframe) {
              return iframe && $.globalEval($(iframe[0].body).text());
          }
      }
  });

}));