index.js

var http = module.exports;
var EventEmitter = require('events').EventEmitter;
var Request = require('./lib/request');
var url = require('url')

http.request = function (params, cb) {
    if (typeof params === 'string') {
        params = url.parse(params)
    }
    if (!params) params = {};
    if (!params.host && !params.port) {
        params.port = parseInt(window.location.port, 10);
    }
    if (!params.host && params.hostname) {
        params.host = params.hostname;
    }

    if (!params.protocol) {
        if (params.scheme) {
            params.protocol = params.scheme + ':';
        } else {
            params.protocol = window.location.protocol;
        }
    }

    if (!params.host) {
        params.host = window.location.hostname || window.location.host;
    }
    if (/:/.test(params.host)) {
        if (!params.port) {
            params.port = params.host.split(':')[1];
        }
        params.host = params.host.split(':')[0];
    }
    if (!params.port) params.port = params.protocol == 'https:' ? 443 : 80;
    
    var req = new Request(new xhrHttp, params);
    if (cb) req.on('response', cb);
    return req;
};

http.get = function (params, cb) {
    params.method = 'GET';
    var req = http.request(params, cb);
    req.end();
    return req;
};

http.Agent = function () {};
http.Agent.defaultMaxSockets = 4;

var xhrHttp = (function () {
    if (typeof window === 'undefined') {
        throw new Error('no window object present');
    }
    else if (window.XMLHttpRequest) {
        return window.XMLHttpRequest;
    }
    else if (window.ActiveXObject) {
        var axs = [
            'Msxml2.XMLHTTP.6.0',
            'Msxml2.XMLHTTP.3.0',
            'Microsoft.XMLHTTP'
        ];
        for (var i = 0; i < axs.length; i++) {
            try {
                var ax = new(window.ActiveXObject)(axs[i]);
                return function () {
                    if (ax) {
                        var ax_ = ax;
                        ax = null;
                        return ax_;
                    }
                    else {
                        return new(window.ActiveXObject)(axs[i]);
                    }
                };
            }
            catch (e) {}
        }
        throw new Error('ajax not supported in this browser')
    }
    else {
        throw new Error('ajax not supported in this browser');
    }
})();

http.STATUS_CODES = {
    100 : 'Continue',
    101 : 'Switching Protocols',
    102 : 'Processing',                 // RFC 2518, obsoleted by RFC 4918
    200 : 'OK',
    201 : 'Created',
    202 : 'Accepted',
    203 : 'Non-Authoritative Information',
    204 : 'No Content',
    205 : 'Reset Content',
    206 : 'Partial Content',
    207 : 'Multi-Status',               // RFC 4918
    300 : 'Multiple Choices',
    301 : 'Moved Permanently',
    302 : 'Moved Temporarily',
    303 : 'See Other',
    304 : 'Not Modified',
    305 : 'Use Proxy',
    307 : 'Temporary Redirect',
    400 : 'Bad Request',
    401 : 'Unauthorized',
    402 : 'Payment Required',
    403 : 'Forbidden',
    404 : 'Not Found',
    405 : 'Method Not Allowed',
    406 : 'Not Acceptable',
    407 : 'Proxy Authentication Required',
    408 : 'Request Time-out',
    409 : 'Conflict',
    410 : 'Gone',
    411 : 'Length Required',
    412 : 'Precondition Failed',
    413 : 'Request Entity Too Large',
    414 : 'Request-URI Too Large',
    415 : 'Unsupported Media Type',
    416 : 'Requested Range Not Satisfiable',
    417 : 'Expectation Failed',
    418 : 'I\'m a teapot',              // RFC 2324
    422 : 'Unprocessable Entity',       // RFC 4918
    423 : 'Locked',                     // RFC 4918
    424 : 'Failed Dependency',          // RFC 4918
    425 : 'Unordered Collection',       // RFC 4918
    426 : 'Upgrade Required',           // RFC 2817
    428 : 'Precondition Required',      // RFC 6585
    429 : 'Too Many Requests',          // RFC 6585
    431 : 'Request Header Fields Too Large',// RFC 6585
    500 : 'Internal Server Error',
    501 : 'Not Implemented',
    502 : 'Bad Gateway',
    503 : 'Service Unavailable',
    504 : 'Gateway Time-out',
    505 : 'HTTP Version Not Supported',
    506 : 'Variant Also Negotiates',    // RFC 2295
    507 : 'Insufficient Storage',       // RFC 4918
    509 : 'Bandwidth Limit Exceeded',
    510 : 'Not Extended',               // RFC 2774
    511 : 'Network Authentication Required' // RFC 6585
};