crossDomain-rc.js

(function(win, doc, undefined) {
	
	var slice = Array.prototype.slice;
	var urlReg = /^[^:]+:\/*[^\/]+/;
	var messageSport = !!win.postMessage ? 'postMessage' : 'name';
	var hasOwn = Object.prototype.hasOwnProperty;
	var emptyFun = function () {};
	
	//============================公共函数===========================
	var util = {
		addEvent: doc.attachEvent ? function(element, event, fn) {
			element.attachEvent('on' + event, fn);
		} : function(element, event, fn) {
			element.addEventListener(event, fn, false);
		},	
		isSameDomain: function (urlA, urlB) {//简单写的，可能有误
			var strA = urlA.match(urlReg)[0].replace(/:80$/,'').replace(/:\/+/,''),strB = urlB.match(urlReg)[0].replace(/:80$/,'').replace(/:\/+/,'');
			return  strA == strB;
		},
		 /**
		  * win动态添加ifrme结点，设置url，载入后回调
		  * @param {window} win window对象
		  * @param {String} url ifrme地址
		  * @param {Function} callback？ifrme加载完成，回调方法
		  * @return {Node} ifrme结点
		  */
		iframeLoad : function(win, url, callback) {
			var doc = win.document;
			var frame = doc.createElement("iframe");
			if(!!url) {
				frame.src = url;
			}
			frame.style.cssText = "position:absolute;left:-2000px;width:1px;height:1px;";
			if(!!callback) {
				util.addEvent(frame, 'load', callback);
			}
			doc.body.appendChild(frame);
			return frame;
		},
		 /**
		  * 对象obj的name方法重写，增加setReady方法
		  *     在调用setReady之前，调用函数，存储参数入list，
		  *     在调用setReady时，批量执行list存储的参数
		  *     在调用setReady之后，调用函数，立即执行，
		  * @param {Object} obj 对象
		  * @param {String} name 方法的对应属性名字
		  * @return {Node} ifrme结点
		  */
		runReady : function(obj, name) {
			var fun = obj[name];
			var _ready = false;
			var _list = [];
			obj[name] = function() {
				if(_ready == false) {
					_list.push(arguments);
				} else {
					fun.apply(obj, arguments);
				}
			};
			obj[name].setReady = function() {
				if(_ready == false) {
					_ready = true;
					while(_list.length > 0) {
						fun.apply(obj, _list.shift());
					}
				}
			};
		}
	};
	
	if (!win.getCrossDomain) {
		//============================通信对象===========================
		//底层通信对象
		var uuid = 0;
		var prefixMap = {};
		var prefixManage = {
			set: function (oldPrefix, newPrefix) {
				if (!!oldPrefix&&prefixMap[oldPrefix]) {
					prefixMap[oldPrefix]--;
				}
				prefixMap[newPrefix] = prefixMap[newPrefix] || 0;
				prefixMap[newPrefix]++;
			},
			isUnique: function (prefix) {
				return prefixMap[prefix] ==1;
			},
			getNew: function (oldPrefix) {
				var prefix = oldPrefix;
				while (prefixMap[prefix] > 0) {
					uuid++;
					prefix = '_'+uuid+'_'+oldPrefix;
				}
				return prefix;
			}
		};
		function message() {
			var hash = '';
			var message = {
				sport : messageSport,
				send : messageSport == 'name'? function(data) {//send(编码)
					this.proxy.name = data;
				}:  function(data) {
					this.proxy.postMessage(data, '*');
				},
				get : function(data) {//get(解码),绑定该get
					this.child.get(data);
				},
				//监听指定window的message事件，或name的改变
				bindMessage: function (win) {
					if (messageSport == 'postMessage') {
						util.addEvent(win,'message', function (e) {
							message.get(e.data);
						})
					} else {
						hash = win.name;//忽略页面当前的name值
						setInterval(function() {
							if(win.name != hash) {
								hash = win.name;
								message.get(hash);
							}
						}, 50);
					}
				},
				//设置方法或属性，通过原型继承读取
				set: function (name, value) {
					if( typeof name == 'string') {
						if (name == 'prefix') {
							prefixManage.set(this.prefix, value);
						}
						message[name] = value;
					} else {
						for (var i in name) {
							if(hasOwn.call(name, i)) {
								this.set(i, name[i]);
							}
						}
					}
				}
			};
			//默认多参数支持方式，需要JSON支持，需要自行设置，见example
			message.set({
				params2str: function () {
					return slice.call(arguments).join('<{PA}>');
				},
				str2params: function (str) {
					return str.split('<{PA}>');
				}
			});
			return message;
		};
		
		//修正IE,使IE支持多消息的支持
		function ieMessage (message, ieSeparator) {
			ieSeparator || (ieSeparator = ['<{IE}>', '{<IE>}']);
			var sendMap = {};//主动发出的消息
			var cancelMap = {};//正在处理中的数据，通知不需要再传送
			
			function push(ary, obj) {//obj的值，添加到ary数组中
				for(var i in obj) {
					if(hasOwn.call(obj, i)) {
						ary.push(obj[i]);
					}
				}
				return ary;
			}
			
			function postStr(separator) {
				var ary = [];
				push(ary, sendMap);
				push(ary, cancelMap);
				return ary.join(separator);
			}
			
			var fun = function () {};
			fun.prototype = message;
			var resultObj = new fun();
			message.child = resultObj;
			
			resultObj.set('ieSeparator', ieSeparator);
			resultObj.send = function (opt, uid) {
				//  12345
				//=>S<{IE}>0<{IE}>12345
				//  67890
				//=>S<{IE}>0<{IE}>12345{<IE>}S<{IE}>1<{IE}>67890
				//  C,0
				//=>S<{IE}>0<{IE}>12345{<IE>}S<{IE}>1<{IE}>67890{<IE>}C<{IE}>0
				var data;
				var ieSeparator = this.ieSeparator;
				if (opt == 'C' && !!uid){//发送“取消发送”的消息
					cancelMap[uid] = [opt,uid].join(ieSeparator[0]);
				} else {
					data = opt;
					uid = uuid++;
					sendMap[uid] = ['S',uid,data].join(ieSeparator[0]);
				}
				message.send(postStr(ieSeparator[1]));
			};
			resultObj.get = function (data) {
				//  S<{IE}>0<{IE}>12345{<IE>}S<{IE}>1<{IE}>67890{<IE>}C<{IE}>0
				//=>S<{IE}>0<{IE}>12345
				//=>S<{IE}>1<{IE}>67890
				var ieSeparator = this.ieSeparator;
				var datas = data.split(ieSeparator[1]), map = {};
				var params, opt, uid;
				for(var i = 0, len = datas.length; i < len; i++) {
					params = datas[i].split(ieSeparator[0]);
					opt = params.shift(); 
					uid = params.shift();
					data = params.join(ieSeparator[0]);
					if(opt == 'S') {
						map[uid] = 1;
						if (!cancelMap[uid]) { //未处理过，进行处理
							this.send('C', uid);
							this.child.get(data);
						}
					} else if(opt == 'C'){
						delete sendMap[uid];//消息来源端 接收到C命令，则下次不在传送
					}
				}
				for (var i in cancelMap) {
					if(hasOwn.call(cancelMap, i) && !hasOwn.call(map, i)) {
						delete cancelMap[i];//没有传过来，表示C命令消息来源端已执行
					}
				}
			};
			return resultObj;
		}

		//消息前缀
		function prefixMessage (message, prefix) {
			var fun = function () {};
			fun.prototype = message;
			var resultObj = new fun();
			message.child = resultObj;
			
			resultObj.set('prefix', prefix||'_crossD_');//多个使用默认存在问题，建议clientUrl MD5签名
			resultObj.send =  function (data) {
				message.send(this.prefix+data);
			};
			resultObj.get = function (str) {
				if (!!str && str.indexOf(this.prefix) == 0) {//解码成功，且前缀为prefix，对消息进行了过滤
					this.child.get(str.substr(this.prefix.length));
				}
			};
			return resultObj;
		}

		//回调机制的支持，callback进行缓存，对应消息返回时，对消息内容执行对应的callback
		function callbackMessage (message, cbSeparator) {
			cbSeparator || (cbSeparator = '<{CB}>');
			var _callbackMap = {};
			
			var fun = function () {};
			fun.prototype = message;
			var resultObj = new fun();
			message.child = resultObj;
			
			resultObj.set('cbSeparator', cbSeparator);
			resultObj.send = function (opt, uid, data) {
				//   '123456', fn
				// =>'S<{CB}>1<{CB}>1<{CB}>123456'
				//   '123456'
				// =>'S<{CB}>1<{CB}>0<{CB}>123456'
				//   'B',2,'abcde'
				// =>'B<{CB}>2<{CB}>abcde'
				var callback, needCallback = 0;
				var cbSeparator = this.cbSeparator;
				if (opt == 'B' && !!data) {
					message.send(['B',uid,data].join(cbSeparator));
				} else {
					callback = uid;
					data = opt;
					uid = uuid++;
					if (!!callback) {
						needCallback = 1;
						_callbackMap[uid] = callback;//缓存回调方法
					}
					message.send(['S',uid,needCallback,data].join(cbSeparator));
				}
			};
			resultObj.get = function (str) {
				//  'S<{CB}>1<{CB}>1<{CB}>123456'
				//=>123456,function send('B',1, resultStr);
				//  'B<{CB}>2<{CB}>abcde'
				//=>回调(abcde)
				var cbSeparator = this.cbSeparator;
				var params = str.split(cbSeparator), callback;
				var needCallback, data;
				var opt = params.shift(), uid = params.shift();
				if(opt == 'S') {
					needCallback = params.shift();
					data = params.join(cbSeparator);
					if (needCallback == 1) {
						callback = function () {
							resultObj.send('B',uid, message.params2str.apply(message, arguments));
						}
					} else {
						callback = emptyFun;
					}
					this.child.get(data, callback);
				} else {
					//回调执行 结果
					data = params.join(cbSeparator);
					if (!!_callbackMap[uid]) {//多个情况，不一定是存在的
						_callbackMap[uid].apply(null, message.str2params(data));
						delete _callbackMap[uid];
					}
				}
			};
			return resultObj;
		}	
		
		//处理命令，相关消息处理，统一通过command.exec方法进行执行
		function dealMessage (cbmessage, command) {
			
			var fun = function () {};
			fun.prototype = cbmessage;
			var resultObj = new fun();
			cbmessage.child = resultObj;
			resultObj.child = null;
			
			resultObj.set('command', command);
			resultObj.send = function () {//fnName, params, callback
				//   'fnName', 'a', 'b', callback
				// =>'fnName<{DEL}>a<{DEL}>b',callback
				//   'fnName', 'a'
				// =>'fnName<{DEL}>a'
				var l = arguments.length, callback = arguments[l - 1];
				if( typeof callback == 'function') {
					cbmessage.send(cbmessage.params2str.apply(cbmessage, slice.call(arguments, 0, -1)),callback);
				} else {
					cbmessage.send(cbmessage.params2str.apply(cbmessage, slice.call(arguments)));
				}
			};
			resultObj.get = function (str, callback) {
				//  '123456<{PA}>abcd',callback
				//=>command.exec('123456','abcd',callback)
				//=>S<{IE}>1<{IE}>67890
				var params =  cbmessage.str2params(str);
				var command = this.command;
				params.push(callback)
				command.exec.apply(command, params);
			};
			return resultObj;
		}	


		//命令对象
		function Command () {
			this.command = {}; 
		}
		Command.prototype = {
			/**
			 * 执行命令函数
			 * @param {String} name 命令函数名
			 * @param {String} params{0,} 传递给 目标页面的命令方法 的参数，只支持string
			 * @param {Function} callback 成功的回调函数，默认为空函数
			 */
			exec : function() {
				var name = arguments[0], args = slice.call(arguments, 1);
				var fun = this.command[name];
				if (fun !== undefined) {//没有定义的命令，不处理
					if( typeof fun == 'function') {
						fun.apply(this.command, args);
					} else {
						//对应的属性是数值或字符串，直接执行回调
						var len = arguments.length;
						arguments[len-1](fun);
					}
				}
			},
			/**
			 * this.command 添加属性，参数为一个时，则传入Object,将Object的自己的属性扩展到command上
			 * @param {String|Object} name String时key值
			 * @param {Function} fun 函数方法
			 */
			add : function(name, fun) {
				if(arguments.length == 1) {
					for(var i in name) {
						if(hasOwn.call(name, i)) {
							this.command[i] = name[i];
						}
					}
				} else {
					this.command[name] = fun;
				}
				return this;
			}
		};
	  
		/**
		 * 获取跨域对象
		 * @param {Object} config配置对象
		 * @return {Object} ifrme结点
		 */
		var href = location.href;
		win.getCrossDomain = function (config) {
			var messageObj;
			var mainCommand = new Command();//主端命令
			var clientCommand = new Command();//客户端命令
			
			var clientUrl = config.clientUrl;
			var aboutBlank = config.aboutBlank||'IE';//'IE','ALL'
			var isSameDomain = config.isSameDomain === undefined ? util.isSameDomain(href, clientUrl):!!config.isSameDomain;//当前页面和API提供地址是不是同域
			//获取消息对象
			var getMessaage = messageSport == 'name'? function (isBindMessage) {
				var obj = dealMessage(callbackMessage(ieMessage(prefixMessage(message(), config.prefix))));
				util.runReady(obj, 'send');
				if (isBindMessage !== false) {
					obj.bindMessage(win);
				}
				return obj;
			}: function (isBindMessage) {
				var obj = dealMessage(callbackMessage(prefixMessage(message(), config.prefix)));
				util.runReady(obj, 'send');
				if (isBindMessage !== false) {
					obj.bindMessage(win);
				}
				return obj;
			};
			var isClient = href.indexOf(clientUrl) != -1;
			
			//消息队列，不跨域情况的支持
			var commandList = [];
			commandList.exec = function () {
				var name = arguments[0];
				for (var i=0,len=this.length; i<len; i++) {
					if  (!!this[i].command[name]) {
						this[i].exec.apply(this[i], arguments);
						return;
					}
				}
			};
			
			var pageType = 0;

			if(isClient == true) {//iframe页
				pageType = 2;
				messageObj = getMessaage();
				messageObj.send.setReady();
				messageObj.set({proxy:win.parent,command:clientCommand});
				clientCommand.add('__setPrefix', function (str, callback) {
					callback();
					messageObj.set('prefix', str);
				});
			} else if (isSameDomain) {//没有跨域，没有跨域，多参不需要转成字符串，所以默认就支持多种格式,【测试，没有具体情况】
				pageType = 3;
				commandList.push(clientCommand,mainCommand);
				messageObj = {
					send : function() {
						var command = this.command, arg;
						var callback = arguments[arguments.length-1];
						if (typeof callback == 'function') {
							command.exec.apply(command, arguments);
						} else {
							arg = slice.call(arguments);
							arg.push(emptyFun);
							command.exec.apply(command, arg);
						}
						
					},
					command: commandList//既是客户端，也是主端
				};
			} else {
				//主端
				if (aboutBlank == 'IE' && messageSport == 'postMessage') {
					messageObj = getMessaage();
					var frame = util.iframeLoad(win, clientUrl, function() {
						messageObj.set('proxy', frame.contentWindow);
						messageObj.send.setReady();
					});
					
					if (!prefixManage.isUnique(messageObj.prefix)) {//不止一个使用该前缀
						var prefix = prefixManage.getNew(messageObj.prefix);
						messageObj.send('__setPrefix',prefix ,function () {
							messageObj.set('prefix', prefix);
						})					
					}

				} else if (aboutBlank != 'IE'|| (aboutBlank == 'IE' && messageSport == 'name')) {
					messageObj = getMessaage(false);
					var frame = util.iframeLoad(win, '', function() {
						messageObj.bindMessage(frame.contentWindow);
						var proxframe = util.iframeLoad(frame.contentWindow, clientUrl, function() {
							messageObj.set('proxy',proxframe.contentWindow);
							messageObj.send.setReady();
						});
					});
				}
				messageObj.set('command', mainCommand);			
				pageType = 1;
			}
			
			return {
				message: messageObj, //通信对象
				mainCommand: mainCommand, 
				clientCommand: clientCommand,
				isMain: function () { //判断当前页面主端
					return (pageType == 1 || pageType == 3);
				},
				isClient: function () { //判断当前页面客户端
					return (pageType == 2 || pageType == 3);
				}
			}
		};
	}
})(this, document);