heist-async-0.3.0.0: js/reqwest.js

/*!
  * Reqwest! A x-browser general purpose XHR connection manager
  * copyright Dustin Diaz 2011
  * https://github.com/ded/reqwest
  * license MIT
  */
!function (window) {
  var twoHundo = /^20\d$/,
      doc = document,
      byTag = 'getElementsByTagName',
      head = doc[byTag]('head')[0],
      xhr = ('XMLHttpRequest' in window) ?
        function () {
          return new XMLHttpRequest();
        } :
        function () {
          return new ActiveXObject('Microsoft.XMLHTTP');
        };

  var uniqid = 0;
  // data stored by the most recent JSONP callback
  var lastValue;

  function readyState(o, success, error) {
    return function () {
      if (o && o.readyState == 4) {
        if (twoHundo.test(o.status)) {
          success(o);
        } else {
          error(o);
        }
      }
    };
  }

  function setHeaders(http, options) {
    var headers = options.headers || {};
    headers.Accept = headers.Accept || 'text/javascript, text/html, application/xml, text/xml, */*';
    headers['X-Requested-With'] = headers['X-Requested-With'] || 'XMLHttpRequest';
    if (options.data) {
      headers['Content-type'] = headers['Content-type'] || 'application/x-www-form-urlencoded';
      for (var h in headers) {
        headers.hasOwnProperty(h) && http.setRequestHeader(h, headers[h], false);
      }
    }
  }

  function getCallbackName(o) {
    var callbackVar = o.jsonpCallback || "callback";
    if (o.url.slice(-(callbackVar.length + 2)) == (callbackVar + "=?")) {
      // Generate a guaranteed unique callback name
      var callbackName = "reqwest_" + uniqid++;

      // Replace the ? in the URL with the generated name
      o.url = o.url.substr(0, o.url.length - 1) + callbackName;
      return callbackName;
    } else {
      // Find the supplied callback name
      var regex = new RegExp(callbackVar + "=([\\w]+)");
      return o.url.match(regex)[1];
    }
  }

  // Store the data returned by the most recent callback
  function generalCallback(data) {
    lastValue = data;
  }

  function getRequest(o, fn, err) {
    if (o.type == 'jsonp') {
      var script = doc.createElement('script');

      // Add the global callback
      window[getCallbackName(o)] = generalCallback;

      // Setup our script element
      script.type = "text/javascript";
      script.src = o.url;
      script.async = true;

      var onload = function () {
        // Call the user callback with the last value stored
        // and clean up values and scripts.
        o.success && o.success(lastValue);
        lastValue = undefined;
        head.removeChild(script);
      };

      script.onload = onload;
      // onload for IE
      script.onreadystatechange = function () {
        /^loaded|complete$/.test(script.readyState) && onload();
      };

      // Add the script to the DOM head
      head.appendChild(script);
    } else {
      var http = xhr();
      http.open(o.method || 'GET', typeof o == 'string' ? o : o.url, true);
      setHeaders(http, o);
      http.onreadystatechange = readyState(http, fn, err);
      o.before && o.before(http);
      http.send(o.data || null);
      return http;
    }
  }

  function Reqwest(o, fn) {
    this.o = o;
    this.fn = fn;
    init.apply(this, arguments);
  }

  function setType(url) {
    if (/\.json$/.test(url)) {
      return 'json';
    }
    if (/\.jsonp$/.test(url)) {
      return 'jsonp';
    }
    if (/\.js$/.test(url)) {
      return 'js';
    }
    if (/\.html?$/.test(url)) {
      return 'html';
    }
    if (/\.xml$/.test(url)) {
      return 'xml';
    }
    return 'js';
  }

  function init(o, fn) {
    this.url = typeof o == 'string' ? o : o.url;
    this.timeout = null;
    var type = o.type || setType(this.url), self = this;
    fn = fn || function () {};

    if (o.timeout) {
      this.timeout = setTimeout(function () {
        self.abort();
        error();
      }, o.timeout);
    }

    function complete(resp) {
      o.complete && o.complete(resp);
    }

    function success(resp) {
      o.timeout && clearTimeout(self.timeout) && (self.timeout = null);
      var r = resp.responseText, JSON;

      switch (type) {
      case 'json':
        resp = JSON ? JSON.parse(r) : eval('(' + r + ')');
        break;
      case 'js':
        resp = eval(r);
        break;
      case 'html':
        resp = r;
        break;
      // default is the response from server
      }

      fn(resp);
      o.success && o.success(resp);
      complete(resp);
    }

    function error(resp) {
      o.error && o.error(resp);
      complete(resp);
    }

    this.request = getRequest(o, success, error);
  }

  Reqwest.prototype = {
    abort: function () {
      this.request.abort();
    },

    retry: function () {
      init.call(this, this.o, this.fn);
    }
  };

  function reqwest(o, fn) {
    return new Reqwest(o, fn);
  }

  function enc(v) {
    return encodeURIComponent(v);
  }

  function serial(el) {
    var n = el.name;
    // don't serialize elements that are disabled or without a name
    if (el.disabled || !n) {
      return '';
    }
    n = enc(n);
    switch (el.tagName.toLowerCase()) {
    case 'input':
      switch (el.type) {
      // silly wabbit
      case 'reset':
      case 'button':
      case 'image':
      case 'file':
        return '';
      case 'checkbox':
      case 'radio':
        return el.checked ? n + '=' + (el.value ? enc(el.value) : true) + '&' : '';
      default: // text hidden password submit
        return n + '=' + (el.value ? enc(el.value) : '') + '&';
      }
      break;
    case 'textarea':
      return n + '=' + enc(el.value) + '&';
    case 'select':
      // @todo refactor beyond basic single selected value case
      return n + '=' + enc(el.options[el.selectedIndex].value) + '&';
    }
    return '';
  }

  reqwest.serialize = function (form) {
    var inputs = form[byTag]('input'),
        selects = form[byTag]('select'),
        texts = form[byTag]('textarea');
    return (v(inputs).chain().toArray().map(serial).value().join('') +
    v(selects).chain().toArray().map(serial).value().join('') +
    v(texts).chain().toArray().map(serial).value().join('')).replace(/&$/, '');
  };

  reqwest.serializeArray = function (f) {
    for (var pairs = this.serialize(f).split('&'), i = 0, l = pairs.length, r = [], o; i < l; i++) {
      pairs[i] && (o = pairs[i].split('=')) && r.push({name: o[0], value: o[1]});
    }
    return r;
  };

  var old = window.reqwest;
  reqwest.noConflict = function () {
    window.reqwest = old;
    return this;
  };

  // defined as extern for Closure Compilation
  // do not change to (dot) '.' syntax
  window['reqwest'] = reqwest;

}(this);