JSONP

/**
 * 功能类库
 */
 /**
  * [util 工具类]
  * @type {Object}
  */
 var util = {};

 /**
  * [function 返回数组的指定项]
  * @param  {[type]} array [description]
  * @param  {[type]} item  [description]
  * @return {[type]}       [description]
  */
 util.indexOf = function (array, item) {
     for (var i = 0; i < array.length; i++) {
         if (array[i] === item) {
             return i;
         }
     }
     return -1;
 };

 /**
  * [function 判断是否为函数]
  * @param  {[type]} source [description]
  * @return {[type]}        [description]
  */
 util.isFunction = function (source) {
     return '[object Function]' === Object.prototype.toString.call(source);
 };

 /**
  * [isIE 判断是不是ie]
  * @return {Boolean} [如果是ie返回版本号，不是则返回false]
  */
 util.isIE = function () {
     var myNav = navigator.userAgent.toLowerCase();
     return (myNav.indexOf('msie') != -1) ? parseInt(myNav.split('msie')[1]) : false;
 };

 /**
  * [function 对象浅复制]
  * @param  {[type]} dst [description]
  * @param  {[type]} obj [description]
  * @return {[type]}     [description]
  */
 util.extend = function (dst, obj) {
     for (var i in obj) {
         if (obj.hasOwnProperty(i)) {
             dst[i] = obj[i];
         }
     }
 };

 /**
  * [function 获取一个随机的5位字符串]
  * @param  {[type]} prefix [description]
  * @return {[type]}        [description]
  */
 util.getName = function (prefix) {
     return prefix + Math.random().toString(36).replace(/[^a-z]+/g, '').substr(0, 5);
 };

 /**
  * [function 在页面中注入js脚本]
  * @param  {[type]} url     [description]
  * @param  {[type]} charset [description]
  * @return {[type]}         [description]
  */
 util.createScript = function (url, charset) {
     var script = document.createElement('script');
     script.setAttribute('type', 'text/javascript');
     charset && script.setAttribute('charset', charset);
     script.setAttribute('src', url);
     script.async = true;
     return script;
 };

 /**
  * [function jsonp]
  * @param  {[type]} url      [description]
  * @param  {[type]} onsucess [description]
  * @param  {[type]} onerror  [description]
  * @param  {[type]} charset  [description]
  * @return {[type]}          [description]
  */
 util.jsonp = function (url, onsuccess, onerror, charset) {
     var callbackName = util.getName('tt_player');
     window[callbackName] = function () {
         if (onsuccess && util.isFunction(onsuccess)) {
             onsuccess(arguments[0]);
         }
     };
     var script = util.createScript(url + '&callback=' + callbackName, charset);
     script.onload = script.onreadystatechange = function () {
         if (!script.readyState || /loaded|complete/.test(script.readyState)) {
             script.onload = script.onreadystatechange = null;
             // 移除该script的 DOM 对象
             if (script.parentNode) {
                 script.parentNode.removeChild(script);
             }
             // 删除函数或变量
             window[callbackName] = null;
         }
     };
     script.onerror = function () {
         if (onerror && util.isFunction(onerror)) {
             onerror();
         }
     };
     document.getElementsByTagName('head')[0].appendChild(script);
 };

/**
 * [json 实现ajax的json]
 * @param  {[type]} options [description]
 * @return {[type]}         [description]
 */
 util.json = function (options) {
     var opt = {
         url: '',
         type: 'get',
         data: {},
         success: function () {},
         error: function () {},
     };
     util.extend(opt, options);
     if (opt.url) {
         var xhr = XMLHttpRequest
            ? new XMLHttpRequest()
            : new ActiveXObject('Microsoft.XMLHTTP');
         var data = opt.data,
             url = opt.url,
             type = opt.type.toUpperCase(),
             dataArr = [];
         for (var k in data) {
             dataArr.push(k + '=' + data[k]);
         }
         if (type === 'GET') {
             url = url + '?' + dataArr.join('&');
             xhr.open(type, url.replace(/\?$/g, ''), true);
             xhr.send();
         }
         if (type === 'POST') {
             xhr.open(type, url, true);
             xmlhttp.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
             xhr.send(dataArr.join('&'));
         }
         xhr.onload = function () {
             if (xhr.status === 200 || xhr.status === 304) {
                 var res;
                 if (opt.success && opt.success instanceof Function) {
                     res = xhr.responseText;
                     if (typeof res ==== 'string') {
                         res = JSON.parse(res);
                         opt.success.call(xhr, res);
                     }
                 }
             } else {
                 if (opt.error && opt.error instanceof Function) {
                     opt.error.call(xhr, res);
                 }
             }
         };
     }
 };

 /**
  * [function crc32加密]
  * @param  {[type]} str [description]
  * @return {[type]}     [description]
  */
 util.crc32 = function (url) {
     var a = document.createElement('a');
     a.href = url;
     var T = (function () {
         var c = 0,
             table = new Array(256);
         for (var n = 0; n != 256; ++n) {
             c = n;
             c = ((c & 1) ? (-306674912 ^ (c >>> 1)) : (c >>> 1));
             c = ((c & 1) ? (-306674912 ^ (c >>> 1)) : (c >>> 1));
             c = ((c & 1) ? (-306674912 ^ (c >>> 1)) : (c >>> 1));
             c = ((c & 1) ? (-306674912 ^ (c >>> 1)) : (c >>> 1));
             c = ((c & 1) ? (-306674912 ^ (c >>> 1)) : (c >>> 1));
             c = ((c & 1) ? (-306674912 ^ (c >>> 1)) : (c >>> 1));
             c = ((c & 1) ? (-306674912 ^ (c >>> 1)) : (c >>> 1));
             c = ((c & 1) ? (-306674912 ^ (c >>> 1)) : (c >>> 1));
             table[n] = c;
         }
         return typeof Int32Array !=== 'undefined' ? new Int32Array(table) : table;
     })();
     var crc32_str = function (str) {
         var C = -1;
         for (var i = 0, L = str.length, c, d; i < L;) {
             c = str.charCodeAt(i++);
             if (c < 0x80) {
                 C = (C >>> 8) ^ T[(C ^ c) & 0xFF];
             } else if (c < 0x800) {
                 C = (C >>> 8) ^ T[(C ^ (192 | ((c >> 6) & 31))) & 0xFF];
                 C = (C >>> 8) ^ T[(C ^ (128 | (c & 63))) & 0xFF];
             } else if (c >= 0xD800 && c < 0xE000) {
                 c = (c & 1023) + 64;
                 d = str.charCodeAt(i++) & 1023;
                 C = (C >>> 8) ^ T[(C ^ (240 | ((c >> 8) & 7))) & 0xFF];
                 C = (C >>> 8) ^ T[(C ^ (128 | ((c >> 2) & 63))) & 0xFF];
                 C = (C >>> 8) ^ T[(C ^ (128 | ((d >> 6) & 15) | ((c & 3) << 4))) & 0xFF];
                 C = (C >>> 8) ^ T[(C ^ (128 | (d & 63))) & 0xFF];
             } else {
                 C = (C >>> 8) ^ T[(C ^ (224 | ((c >> 12) & 15))) & 0xFF];
                 C = (C >>> 8) ^ T[(C ^ (128 | ((c >> 6) & 63))) & 0xFF];
                 C = (C >>> 8) ^ T[(C ^ (128 | (c & 63))) & 0xFF];
             }
         }
         return C ^ -1;
     };
     var r = a.pathname + '?r=' + Math.random().toString(10).substring(2);
     if (r[0] != '/') {
         r = '/' + r;
     }
     var s = crc32_str(r) >>> 0;
     var is_web = location.protocol.indexOf('http') > -1;
     return (is_web ? [location.protocol, a.hostname] : ['http:', a.hostname]).join('//') + r + '&s=' + s;
 };

 export default util;