/*
 * jQuery postMessage Transport Plugin 1.0
 * https://github.com/blueimp/jQuery-File-Upload
 *
 * Copyright 2011, Sebastian Tschan
 * https://blueimp.net
 *
 * Licensed under the MIT license:
 * http://www.opensource.org/licenses/MIT
 */

/*jslint unparam: true, nomen: true */
/*global jQuery, window, document */

(function ($) {
    'use strict';

    var counter = 0,
        names = [
            'accepts',
            'cache',
            'contents',
            'contentType',
            'crossDomain',
            'data',
            'dataType',
            'headers',
            'ifModified',
            'mimeType',
            'password',
            'processData',
            'timeout',
            'traditional',
            'type',
            'url',
            'username'
        ],
        convert = function (p) {
            return p;
        };

    $.ajaxSetup({
        converters: {
            'postmessage text': convert,
            'postmessage json': convert,
            'postmessage html': convert
        }
    });

    $.ajaxTransport('postmessage', function (options) {
        if (options.postMessage && window.postMessage) {
            var iframe,
                loc = $('<a>').prop('href', options.postMessage)[0],
                target = loc.protocol + '//' + loc.host,
                xhrUpload = options.xhr().upload;
            return {
                send: function (_, completeCallback) {
                    var message = {
                            id: 'postmessage-transport-' + (counter += 1)
                        },
                        eventName = 'message.' + message.id;
                    iframe = $(
                        '<iframe style="display:none;" src="' +
                            options.postMessage + '" name="' +
                            message.id + '"></iframe>'
                    ).bind('load', function () {
                        $.each(names, function (i, name) {
                            message[name] = options[name];
                        });
                        message.dataType = message.dataType.replace('postmessage ', '');
                        $(window).bind(eventName, function (e) {
                            e = e.originalEvent;
                            var data = e.data,
                                ev;
                            if (e.origin === target && data.id === message.id) {
                                if (data.type === 'progress') {
                                    ev = document.createEvent('Event');
                                    ev.initEvent(data.type, false, true);
                                    $.extend(ev, data);
                                    xhrUpload.dispatchEvent(ev);
                                } else {
                                    completeCallback(
                                        data.status,
                                        data.statusText,
                                        {postmessage: data.result},
                                        data.headers
                                    );
                                    iframe.remove();
                                    $(window).unbind(eventName);
                                }
                            }
                        });
                        iframe[0].contentWindow.postMessage(
                            message,
                            target
                        );
                    }).appendTo(document.body);
                },
                abort: function () {
                    if (iframe) {
                        iframe.remove();
                    }
                }
            };
        }
    });

}(jQuery));
