/*
@desc：ajax请求类
@param obj 传入数据，格式为
{
data:'name=lee&sex=male',           #  提交到后台的数据，""|{}|FormData
url:'http://localhost/test.php',    #  请求的url地址
type:'post',                        #  请求类型，post|get|json|file
async:true                          #  同步/异步，true:异步 false:同步，默认true
}
*/
function ajax(obj){
this.obj = obj
this.xhr
this.data
/*
 @desc：内部方法，查询字符串转json对象
 @param str 查询字符串，格式为："a=b&c=d"
 @return json json对象，如：
 {
    a:"b",
    c:"d"
 }
 */
this.strtojson = function(str){
    var arr = str.split('&')
    var json = {}
    for(var i in arr){
        var k = arr[i].split('=')[0]
        var v = arr[i].split('=')[1]
        json[k] = v
    }
    return json
}
/*
 @desc：内部方法，json对象转查询字符串
 @param json json对象，如：
 {
    a:"b",
    c:"d"
 }
 @return str 查询字符串，格式为："a=b&c=d"
 */
this.jsontostr = function(json){
    var arr = new Array()
    for(var k in json){
        var v = json[k]
        var val = k+'='+v
        arr.push(val)
    }
    var str = arr.join('&')
    return str
}
/*
 @desc：内部方法，解析url地址
 @param url url地址，如：http://www.baidu.com/a/b/c.jpg?a=b&c=d#id
 @return info 解析后的地址，如：
 {
    scheme:'http',          #  协议
    host:'www.baidu.com',   #  域名
    port:'',                #  端口
    user:'',                #  验证用户名
    pass:'',                #  验证密码
    path:a/b,               #  路径
    query:'a=b&c=d',        #  查询字符串
    fragment:'id'           #  锚点
 }
 */
this.parseurl = function(url){
    var reg = /(?:([A-Za-z]+):)?(\/{0,3})?(?:(.*):(.*)@)?([0-9.\-A-Za-z]+)(?::(\d+))?(?:\/([^?#]*))?(?:\?([^#]*))?(?:#(.*))?/
    var res = reg.exec(url)
    var scheme = (res[1])?res[1]:'http'
    var user = (res[3])?res[3]:''
    var pass = (res[4])?res[4]:''
    var host = (res[5])?res[5]:''
    var port = (res[6])?res[6]:'80'
    var path = (res[7])?res[7]:''
    var query = (res[8])?res[8]:''
    var fragment = (res[9])?res[9]:''
    var info = {
        scheme:scheme,
        host:host,
        port:port,
        user:user,
        pass:pass,
        path:path,
        query:query,
        fragment:fragment
    }
    return info
}
/*
 @desc：初始化方法，获得xhr实例
 */
this.init = function(){
    if(window.XMLHttpRequest){
        this.xhr=new XMLHttpRequest()
    }else{
        this.xhr=new ActiveXObject("Microsoft.XMLHTTP")
    }
    return this
}
/*
 @desc：ajax发送前的回调
 */
this.before = function(func){
    this.xhr.addEventListener('readystatechange',function(){
        if(this.readyState < 4){
            func()
        }
    })
    return this
}
/*
 @desc：ajax发送成功后的回调
 */
this.success = function(func){
    this.xhr.addEventListener('readystatechange',function(){
        if (this.readyState == 4 && this.status == 200){
            var res
            if(this.getResponseHeader('content-type')==='application/json'){
                res = JSON.parse(this.responseText)
            }else{
                res = this.responseText
            }
            func(res)
        }
    })
    return this
}
/*
 @desc：ajax发送失败后的回调
 */
this.error = function(func){
    this.xhr.addEventListener('readystatechange',function(){
        if(this.readyState == 4 && this.status != 200){
            this.xhr.abort()
            func()
        }
    })
    return this
}
/*
 @desc：获取ajax发送进度
 */
this.progress = function(func){
    this.xhr.upload.addEventListener('progress',function(e){
        if(e.lengthComputable){
            var loading = Math.round(e.loaded / e.total * 100);
            func(loading)
        }
    })
    return this
}
/*
 @desc：拼凑ajax参数
 */
this.request = function(){
    var obj = this.obj
    var data = obj.data
    var url = obj.url
    var type = obj.type
    var async = (obj.async)?obj.async:true
    var auth = obj.auth
    this.init()
    if(type == 'post'){
        this.xhr.open(type,url,async)
        this.xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded")
        if(data instanceof Object){
            if(data instanceof FormData){
                var obj = {}
                data.forEach(function(val,key){
                    if((key != 'undefined') && (val != 'undefined')){
                        obj[key] = val
                    }
                })
                data = this.jsontostr(obj)
            }else{
                data = this.jsontostr(data)
            }
        }
    }else if(type == 'get'){
        var info = this.parseurl(url)
        var scheme = info.scheme
        var host = info.host
        var port = info.port
        var path = info.path
        var query = info.query
        if(data instanceof Object){
            if(data instanceof FormData){
                var obj = {}
                data.forEach(function(val,key){
                    if((key != 'undefined') && (val != 'undefined')){
                        obj[key] = val
                    }
                })
                data = this.jsontostr(obj)
            }else{
                data = this.jsontostr(data)
            }
        }
        var psep = (path)?'/':''
        var sep = (query || data)?'?':''
        url = scheme+'://'+host+':'+port+psep+path+sep+query+data
        data = ''
        this.xhr.open(type,url,async)
    }else if(type == 'json'){
        this.xhr.open('post',url,async)
        this.xhr.setRequestHeader("Content-type", "application/json")
        if((typeof(data)=='string')||(data instanceof String)){
            data = this.strtojson(data)
        }else if(data instanceof Object){
            if(data instanceof FormData){
                var obj = {}
                data.forEach(function(val,key){
                    if((key != 'undefined') && (val != 'undefined')){
                        obj[key] = val
                    }
                })
                data = obj
            }
        }
        data = JSON.stringify(data)
    }else if(type == 'file'){
        this.xhr.open('post',url,async)
        if((typeof(data)=='string')||(data instanceof String)){
            return false
        }else if(data instanceof Object){
            if(!data instanceof FormData){
                return false
            }
        }
    }
    if(auth){
        this.xhr.withCredentials = true
        this.xhr.setRequestHeader("Authorization", "Basic " + btoa(auth))
    }
    this.data = data
    return this
}
/*
 @desc：发送
 */
this.send = function(){
    this.xhr.send(this.data)
}
}

var ajax = new ajax()
var data = {
data:'name=lee&sex=male',
url:'http://localhost/test.php',
type:'post',
async:true
}
ajax.request(data).progress(
function(loading){
console.log(loading)
}).success(function(data){
console.log(data)
}).error(function(){
console.log(2)
}).send()