/**
 * Request组件, modern版, 支持IE9+,chrome,FF
 * @authors yutent (yutent@doui.cc)
 * @date    2016-11-27 13:08:40
 *
 */

'use strict';
define(['yua', './promise'], function(yua) {
    var _request = function(url, protocol) {
            this.transport = true;
            protocol = (protocol + '').trim().toUpperCase();
            this.xhr = Xhr();
            this.defer = Promise.defer();
            this.opt = {
                url: (url + '').trim(),
                type: protocol || 'GET',
                form: '',
                data: {},
                headers: {},
                timeoutID: 0,
                uuid: Math.random()
                    .toString(16)
                    .substr(2)
            };
        },
        _requestp = _request.prototype,
        toS = Object.prototype.toString,
        win = window,
        doc = win.document,
        encode = encodeURIComponent,
        decode = decodeURIComponent,
        noop = function(e, res) {
            this.defer.resolve(res);
        };

    // -----------------------------

    // 本地协议判断正则
    var rlocalProtocol = /^(?:about|app|app-storage|.+-extension|file|res|widget):$/;
    var isLocal = false;
    try {
        isLocal = rlocalProtocol.test(location.ptyperotocol);
    } catch (e) {}

    var rheaders = /^(.*?):[ \t]*([^\r\n]*)\r?$/gm;

    // ----------------- 一些兼容性预处理 --------------------

    win.Xhr = function() {
        return new XMLHttpRequest();
    };
    var supportCors = 'withCredentials' in Xhr();

    // ------------------- 几个解释方法 -----------------------

    function serialize(p, obj, q) {
        var k;
        if (Array.isArray(obj)) {
            obj.forEach(function(it, i) {
                k = p ? p + '[' + (Array.isArray(it) ? i : '') + ']' : i;
                if (typeof it === 'object') {
                    serialize(k, it, q);
                } else {
                    q(k, it);
                }
            });
        } else {
            for (var i in obj) {
                k = p ? p + '[' + i + ']' : i;
                if (typeof obj[i] === 'object') {
                    serialize(k, obj[i], q);
                } else {
                    q(k, obj[i]);
                }
            }
        }
    }

    var Format = function() {};

    Format.prototype = {
        parseJS: function(code) {
            code = (code + '').trim();
            if (code) {
                if (code.indexOf('use strict') === 1) {
                    var script = doc.createElement('script');
                    script.text = code;
                    doc.head.appendChild(script).parentNode.removeChild(script);
                } else {
                    eval(code);
                }
            }
        },
        parseXML: function(data, xml, tmp) {
            try {
                tmp = new DOMParser();
                xml = tmp.parseFromString(data, 'text/xml');
            } catch (e) {
                xml = void 0;
            }

            if (
                !xml ||
                !xml.documentElement ||
                xml.getElementsByTagName('parsererror').length
            ) {
                console.error('Invalid XML: ' + data);
            }
            return xml;
        },
        parseHTML: function(html) {
            return yua.parseHTML(html);
        },
        param: function(obj) {
            if (!obj || typeof obj === 'string' || typeof obj === 'number')
                return obj;

            var arr = [];
            var q = function(k, v) {
                if (/native code/.test(v)) return;

                v = typeof v === 'function' ? v() : v;
                v = toS.call(v) !== '[object File]' ? encode(v) : v;

                arr.push(encode(k) + '=' + v);
            };

            if (typeof obj === 'object') serialize('', obj, q);

            return arr.join('&');
        },
        parseForm: function(form) {
            var data = {};
            for (var i = 0, field; (field = form.elements[i++]); ) {
                switch (field.type) {
                    case 'select-one':
                    case 'select-multiple':
                        if (field.name.length && !field.disabled) {
                            for (var j = 0, opt; (opt = field.options[j++]); ) {
                                if (opt.selected) {
                                    data[field.name] = opt.value || opt.text;
                                }
                            }
                        }
                        break;
                    case 'file':
                        if (field.name.length && !field.disabled) {
                            data[field.name] = field.files[0];
                        }
                        break;
                    case undefined:
                    case 'submit':
                    case 'reset':
                    case 'button':
                        break; //按钮啥的, 直接忽略
                    case 'radio':
                    case 'checkbox':
                        // 只处理选中的
                        if (!field.checked) break;
                    default:
                        if (field.name.length && !field.disabled) {
                            data[field.name] = field.value;
                        }
                }
            }
            return data;
        },
        merge: function(a, b) {
            if (typeof a !== 'object' || typeof b !== 'object')
                throw new TypeError('argument must be an object');

            if (Object.assign) return Object.assign(a, b);

            for (var i in b) {
                a[i] = b[i];
            }
            return a;
        }
    };

    var F = new Format();

    // ---------------------------------------------------------
    // -------------------- request 模块开始 --------------------
    // ---------------------------------------------------------

    var requestConvert = {
        text: function(val) {
            return val;
        },
        xml: function(val, xml) {
            return xml !== undefined ? xml : F.parseXML(val);
        },
        html: function(val) {
            return F.parseHTML(val);
        },
        json: function(val) {
            return JSON.parse(val);
        },
        script: function(val) {
            return F.parseJS(val);
        },
        jsonp: function(name) {
            var json = request.cache[name];
            delete request.cache[name];
            return json;
        }
    };
    var requestExtend = {
        formData: function() {
            if (this.opt.form) {
                var data = F.parseForm(this.opt.form);
                F.merge(this.opt.data, data);
            }

            var form = new FormData();
            for (var i in this.opt.data) {
                var el = this.opt.data[i];
                if (Array.isArray(el)) {
                    el.forEach(function(it) {
                        form.append(i + '[]', it);
                    });
                } else {
                    form.append(i, this.opt.data[i]);
                }
            }
            return form;
        },
        jsonp: function(jsonpcallback) {
            win[jsonpcallback] = function(val) {
                delete win[jsonpcallback];
                request.cache[jsonpcallback] = val;
            };
        },
        dispatch: function(self) {
            if (!this.transport) return this.defer.reject('Request pending...');

            var _this = this,
                result = {
                    response: {
                        url: this.opt.url,
                        headers: { 'content-type': '' }
                    },
                    request: {
                        url: this.opt.url,
                        headers: _this.opt.headers
                    },
                    status: self === null ? 504 : 200,
                    statusText: self === null ? 'Connected timeout' : 'ok',
                    text: '',
                    body: '',
                    error: null
                };

            //状态为4,既已成功, 则清除超时
            clearTimeout(_this.opt.timeoutID);

            if (
                typeof this.transport === 'object' &&
                this.opt.type === 'JSONP'
            ) {
                //移除script
                // this.transport.parentNode.removeChild(this.transport);

                //超时返回
                if (self !== null) {
                    var exec =
                        !this.transport.readyState ||
                        this.transport.readyState === 'loaded' ||
                        this.transport.readyState === 'complete';

                    if (exec) {
                        result.body = requestConvert.jsonp(
                            this.opt.data.callback
                        );
                        result.text = JSON.stringify(result.body);
                    }
                }

                this.callback(result.error, result);
            } else {
                //成功的回调
                var isSucc = self
                        ? (self.status >= 200 && self.status < 300) ||
                          self.status === 304
                        : false,
                    headers =
                        (self && self.getAllResponseHeaders().split('\n')) ||
                        [];

                //处理返回的Header
                headers.forEach(function(it, i) {
                    it = it.trim();
                    if (it) {
                        it = it.split(':');
                        result.response.headers[
                            it.shift().toLowerCase()
                        ] = it.join(':').trim();
                    }
                });

                if (isSucc) {
                    result.status = self.status;
                    if (result.status === 204) {
                        result.statusText = 'no content';
                    } else if (result.status === 304) {
                        result.statusText = 'not modified';
                    }
                } else {
                    result.status = self === null ? 504 : self.status || 500;
                    result.statusText =
                        self === null
                            ? 'Connected timeout'
                            : self.statusText || 'Internal Server Error';
                    result.error = F.merge(new Error(result.statusText), {
                        status: result.status
                    });
                }

                try {
                    //处理返回的数据
                    var dataType = result.response.headers[
                        'content-type'
                    ].match(/json|xml|script|html/i) || ['text'];

                    dataType = dataType[0].toLowerCase();
                    result.text =
                        (self && (self.responseText || self.responseXML)) || '';
                    result.body = requestConvert[dataType](
                        result.text,
                        self && self.responseXML
                    );
                } catch (err) {
                    result.error = err;
                    result.statusText = 'parse error';
                }

                _this.callback(result.error, result);
            }
            delete _this.defer;
            delete _this.transport;
            delete _this.opt;
            delete _this.xhr;
        }
    };

    // 设置表单类型, 支持2种, form/json
    _requestp.type = function(t) {
        if (this.opt.formType === 'form-data') return this;

        this.opt.formType = t || 'form';
        if (t === 'form' || this.opt.type === 'GET')
            this.set(
                'content-type',
                'application/x-www-form-urlencoded; charset=UTF-8'
            );
        else this.set('content-type', 'application/json; charset=UTF-8');

        return this;
    };

    //设置头信息
    _requestp.set = function(k, val) {
        if (!this.transport) return;

        if (typeof k === 'object') {
            for (var i in k) {
                i = i.toLowerCase();
                this.opt.headers[i] = k[i];
            }
        } else if (typeof k === 'string') {
            if (arguments.length < 2) throw new Error('2 arguments required');

            // 全转小写,避免重复写入
            k = k.toLowerCase();

            if (val === undefined) delete this.opt.headers[k];
            else this.opt.headers[k] = val;
        } else {
            throw new Error(
                'arguments must be string/object, but [' + typeof k + '] given'
            );
        }
        return this;
    };

    //设置请求参数
    _requestp.send = function(k, val) {
        if (!this.transport) return;

        // 1. send方法可以多次调用, 但必须保证格式一致
        // 2. 2次圴提交纯字符串也会抛出异常
        if (typeof k === 'object') {
            if (this.opt.data && typeof this.opt.data === 'string')
                throw new Error(
                    'param can not be string and object at the same time'
                );
            if (!this.opt.data) this.opt.data = {};

            F.merge(this.opt.data, k);
        } else {
            if (typeof k === 'string') {
                if (arguments.length === 1) {
                    if (this.opt.data)
                        throw new Error('invalid param in function send');

                    this.opt.data = k;
                } else {
                    if (this.opt.data && typeof this.opt.data === 'string')
                        throw new Error(
                            'param can not be string and object at the same time'
                        );

                    if (!this.opt.data) this.opt.data = {};

                    this.opt.data[k] = val;
                }
            } else {
                throw new Error(
                    'argument of send must be string/object, but [' +
                        typeof k +
                        '] given'
                );
            }
        }

        return this;
    };

    //该方法用于 form-data类型的post请求的参数设置
    _requestp.field = function(k, val) {
        if (!this.transport) return this;

        // 此类型优先级最高
        this.opt.formType = 'form-data';
        this.opt.type = 'POST';
        if (
            !this.opt.data ||
            (this.opt.data && typeof this.opt.data !== 'object')
        )
            this.opt.data = {};

        if (arguments.length === 1 && typeof k === 'object') {
            F.merge(this.opt.data, k);
        } else if (arguments.length === 2) {
            this.opt.data[k] = val;
        } else {
            throw new TypeError(
                'argument must be an object, but ' + typeof k + ' given'
            );
        }
        return this;
    };

    //设置缓存
    _requestp.cache = function(t) {
        if (!this.transport) return;

        if (this.opt.type === 'GET') this.opt.cache = !!t;

        return this;
    };

    //取消网络请求
    _requestp.abort = function() {
        delete this.transport;
        if (!this.opt.form) this.xhr.abort();

        return this;
    };

    //超时设置, 单位毫秒
    _requestp.timeout = function(time) {
        if (typeof time !== 'number' || time < 1) return this;

        this.opt.timeout = time;
        return this;
    };

    _requestp.form = function(form) {
        if (typeof form === 'object' && form.nodeName === 'FORM') {
            this.opt.type = 'POST';
            this.opt.form = form;
        }

        return this;
    };

    var originAnchor = doc.createElement('a');
    originAnchor.href = location.href;
    _requestp.end = function(callback) {
        var _this = this;
        // 回调已执行, 或已取消, 则直接返回, 防止重复执行
        if (!this.transport) return this;

        if (!this.opt.url) throw new Error('Invalid  request url');

        F.merge(this, requestExtend);

        this.callback = callback || noop.bind(this);

        // 1. url规范化
        this.opt.url = this.opt.url
            .replace(/#.*$/, '')
            .replace(/^\/\//, location.protocol + '//');

        // 2. 处理跨域
        if (typeof this.opt.crossDomain !== 'boolean') {
            var anchor = doc.createElement('a');
            try {
                anchor.href = this.opt.url;
                // IE7及以下浏览器 '1'[0]的结果是 undefined
                // IE7下需要获取绝对路径
                var absUrl = !'1'[0]
                    ? anchor.getAttribute('href', 4)
                    : anchor.href;
                anchor.href = absUrl;
                anchor.async = true;
                this.opt.crossDomain =
                    originAnchor.protocol !== anchor.protocol ||
                    originAnchor.host !== anchor.host;
            } catch (e) {
                this.opt.crossDomain = true;
            }
        }

        // 2.1 进一步处理跨域配置
        if (this.opt.type === 'JSONP') {
            //如果没有跨域，自动转回xhr GET
            if (!this.opt.crossDomain) {
                this.opt.type = 'GET';
            } else {
                this.opt.data['callback'] =
                    this.opt.data['callback'] || 'jsonp' + request.cid++;
                this.jsonp(this.opt.data['callback']); //创建临时处理方法
            }
        }
        // 2.2 如果不是跨域请求，则自动加上一条header信息，用以标识这是ajax请求
        if (!this.opt.crossDomain) {
            this.set('X-Requested-With', 'XMLHttpRequest');
        } else {
            supportCors && (this.xhr.withCredentials = true);
        }

        // 3. data转字符串
        this.opt.param = F.param(this.opt.data);

        // 4. 设置Content-Type类型, 默认x-www-form-urlencoded
        if (!this.opt.formType) this.type('form');

        // 5.处理GET请求
        this.opt.hasContent = this.opt.type === 'POST'; //是否为post请求
        if (!this.opt.hasContent) {
            //GET请求直接把参数拼接到url上
            if (this.opt.param) {
                this.opt.url +=
                    (/\?/.test(this.opt.url) ? '&' : '?') + this.opt.param;
            }
            //加随机值,避免缓存
            if (this.opt.cache === false)
                this.opt.url +=
                    (/\?/.test(this.opt.url) ? '&' : '?') +
                    '_=' +
                    Math.random();
        } else {
            if (this.opt.formType === 'form-data') {
                delete this.opt.headers['content-type'];
                this.opt.param = this.formData();
            } else if (this.opt.formType !== 'form') {
                this.opt.param = JSON.stringify(this.opt.data);
            }
        }

        //jsonp
        if (this.opt.type === 'JSONP') {
            this.transport = doc.createElement('script');
            this.transport.onerror = this.transport.onload = function() {
                _this.dispatch(_this.transport);
            };
            this.transport.src = this.opt.url;
            doc.head.insertBefore(this.transport, doc.head.firstChild);

            //6. 超时处理
            if (this.opt.timeout && this.opt.timeout > 0) {
                this.opt.timeoutID = setTimeout(function() {
                    _this.transport.onerror = _this.transport.onload = null;
                    _this.dispatch(null);
                }, this.opt.timeout);
            }
        } else {
            this.xhr.onreadystatechange = function(ev) {
                if (_this.opt.timeout && _this.opt.timeout > 0) {
                    _this.opt['time' + this.readyState] = ev.timeStamp;
                    if (this.readyState === 4) {
                        _this.opt.isTimeout =
                            _this.opt.time4 - _this.opt.time1 >
                            _this.opt.timeout;
                    }
                }

                if (this.readyState !== 4) {
                    return;
                }

                _this.dispatch(_this.opt.isTimeout ? null : _this.xhr);
            };

            // 6. 初始化xhr提交
            this.xhr.open(this.opt.type, this.opt.url, true);

            // 7. 设置头信息
            for (var i in this.opt.headers) {
                if (this.opt.headers[i])
                    this.xhr.setRequestHeader(i, this.opt.headers[i]);
            }

            // 8. 发起网络请求
            _this.xhr.send(_this.opt.param);

            //超时处理
            if (this.opt.timeout && this.opt.timeout > 0) {
                this.xhr.timeout = this.opt.timeout;
            }
        }
        return this.defer.promise;
    };

    // ---------------------- end ------------------------

    if (!win.request) {
        win.request = {
            get: function(url) {
                if (!url) throw new Error('argument url is required');

                return new _request(url, 'GET');
            },
            post: function(url) {
                if (!url) throw new Error('argument url is required');

                return new _request(url, 'POST');
            },
            jsonp: function(url) {
                if (!url) throw new Error('argument url is required');

                return new _request(url, 'JSONP');
            },
            cache: {},
            cid: 0,
            version: '1.1.0-es5'
        };
        yua.ui.request = request.version;
    }

    return request;
});