(function (win, dom) {

	/**
	 * 参数：
	 * o [object]
	 * o.selid -> 滚动内容盒子的id （必须）
	 * o.width -> 滚动条的宽度 （默认10，请设置为偶数)
	 * o.bgcolor -> 滚动条包裹层的颜色 (默认#eaeaea)
	 * o.barcolor -> 滚动条的颜色 (默认#ccc)
	 * o.entershow -> 是否为鼠标进入包裹层后显示滚动条 （默认true是）
	 * o.hasy -> 是否需要y轴滚动条（默认true需要）
	 * o.hasx -> 是否需要x轴滚动条（默认false不需要）
	 * o.borderradius -> 滚公条圆弧的宽度（默认为o.width的一半）
	 * 注：通过调用myscrollbar.setsize()函数可以重置滚动条高度
	 */
	function myscrollbar (o) {
		this.init(o);
	}

	myscrollbar.prototype.init = function (o) {
		this.bxbar = false;						// 是否有x轴滚动条
		this.bybar = false;						// 是否有y轴滚动条
					
		this.iscrolltop = 0;					// 滚动内容的y轴滚动距离
		this.iscrollleft = 0;					// 滚动内容的x轴滚动距离

		this.byshow = false;					// y轴滚动条显示与否
		this.bxshow = false;					// x轴滚动条显示与否

		this.owrapper = dom.getelementbyid(o.selid);		// 滚动盒子
		this.oscroll = this.owrapper.firstelementchild;		// 滚动内容

		this.setparam(o);									// 调用设置初始参数喊
		this.addscrollbar();								// 调用添加滚动条函数

		this.initstate();									// 调用设置初始状态函数
		this.initevent();									// 调用设置事件函数
	}

	// 初始化状态
	myscrollbar.prototype.initstate = function () {
		// 给包裹层设置默认定位
		var swposition = getstyle(this.owrapper, 'position');
		if(swposition == 'static') {
			setstyle(this.owrapper, {
				position: 'relative'
			})
		}

		setstyle(this.oscroll, {
			position: 'relative'
		})

		if ( this.bybar ) {

			setstyle(this.oybox, {
				display: this.entershow ? 'none' : 'block',			// 如果entershow为true就是需要进入包裹层才显示滚动条
				position: 'absolute',
				top: 0,
				right: 0,
				zindex: 10,
				width: this.width + 'px',
				height: '100%',
				"border-radius":" 30px",
				backgroundcolor: this.bgcolor
			});

			setstyle(this.oybar, {
				position: 'absolute',
				top: 0,
				left: 0,
				width: '100%',
				backgroundcolor: this.barcolor,
				borderradius: this.borderradius + 'px'
			})
		}

		if ( this.bxbar ) {

			setstyle(this.oxbox, {
				display: this.entershow ? 'none' : 'block',			// 如果entershow为true就是需要进入包裹层才显示滚动条
				position: 'absolute',
				bottom: 0,
				left: 0,
				zindex: 10,
				height: this.width + 'px',
				width: '100%',
				backgroundcolor: this.bgcolor
			})

			setstyle(this.oxbar, {
				position: 'absolute',
				bottom: 0,
				left: 0,
				height: '100%',
				backgroundcolor: this.barcolor,
				borderradius: this.borderradius + 'px'
			})
		}

		this.setsize();		// 设置滚动条的宽高
	}

	// 初始化事件
	myscrollbar.prototype.initevent = function () {
		var _this = this;

		// 鼠标在包裹层中然后滚轴上下滚动
		var suseragent = win.navigator.useragent.tolowercase();
		if ( suseragent.indexof('firefox') != -1 ) {
			// 火狐浏览器滚轴滚动
			this.owrapper.addeventlistener('dommousescroll', function (e) {
				if ( _this.bybar && _this.byshow ) {
					e.preventdefault();

					_this.iscrolltop += e.detail > 0 ? 60 : -60;
					_this.iscrolltop = _this.iscrolltop <= 0 ? 0 : _this.iscrolltop >= _this.iscrollh - _this.iwrapperh ? _this.iscrollh - _this.iwrapperh : _this.iscrolltop;
					_this.settranslate();
					_this.setytop(_this.iscrolltop / _this.iscrollh * _this.iyboxh);
				}
			})
		} else {
			// 谷歌、ie滚轴滚动
			this.owrapper.onmousewheel = function (evt) {
				if ( _this.bybar && _this.byshow ) {
					var e = evt || win.event;
					evt ? e.preventdefault() : e.returnvalue = false;

					_this.iscrolltop += e.wheeldelta < 0 ? 60 : -60;
					_this.iscrolltop = _this.iscrolltop <= 0 ? 0 : _this.iscrolltop >= _this.iscrollh - _this.iwrapperh ? _this.iscrollh - _this.iwrapperh : _this.iscrolltop;
					_this.settranslate();
					_this.setytop(_this.iscrolltop / _this.iscrollh * _this.iyboxh);
				}
			}
		}

		// 输入表移入包裹层显示滚动条、移出隐藏滚动条
		var isinwrapper = false;
		this.owrapper.onmouseenter = function () {
			isinwrapper = true;
			if ( _this.entershow ) {
				if ( _this.bybar && _this.byshow ) {
					setstyle(_this.oybox, {
						display: 'block'
					})
				}
				if ( _this.bxbar && _this.bxshow ) {
					setstyle(_this.oxbox, {
						display: 'block'
					})
				}
			}
		}
		this.owrapper.onmouseleave = function () {
			isinwrapper = false;
			if ( _this.entershow ) {
				if ( _this.bybar && !bydown && _this.byshow ) {
					setstyle(_this.oybox, {
						display: 'none'
					})
				}
				if ( _this.bxbar && !bxdown && _this.bxshow ) {
					setstyle(_this.oxbox, {
						display: 'none'
					})
				}
			}
		}


		// 鼠标在滚动条上按下，想要拖动
		var bydown = false, bxdown = false;		// 在滚动条上是否按下
		var byleave = true, bxleave = true;		// 是否离开
		var idownpagey = 0, idownpagex = 0;		// 按下时鼠标到页面顶部的距离
		var iybartop = 0, ixbarleft = 0;		// 按下时滚动条的top/left
		if ( this.bybar ) {
			// 鼠标移上y轴滚动条变色
			if ( this.entercolor ) {
				this.oybar.onmouseenter = function () {
					byleave = false;
					setstyle(this, {
						backgroundcolor: _this.entercolor
					})
				}
				this.oybar.onmouseleave = function () {
					byleave = true;
					if ( !bydown ) {
						setstyle(this, {
							backgroundcolor: _this.barcolor
						})
					}
				}
			}
				
			// 鼠标在y轴滚动条按下
			this.oybar.onmousedown = function (e) {
				if ( _this.byshow ) {
					bydown = true;
					idownpagey = e.clienty + dom.documentelement.scrolltop || dom.body.scrolltop;
					iybartop = parseint(getstyle(this, 'top'));

					// 禁止文本可选中
					canselecttext(false);
				}
			}

			// 鼠标在按下y轴滚动条后抬起
			dom.addeventlistener('mouseup', function () {
				if ( bydown && _this.byshow ) {
					bydown = false;
					// 恢复文本可选中
					canselecttext(true);

	    			if ( !isinwrapper && _this.entershow ) {
	    				setstyle(_this.oybox, {
	    					display: 'none'
	    				})
	    			}
				}
				if ( !bydown && byleave ) {
					setstyle(_this.oybar, {
						backgroundcolor: _this.barcolor
					})
				}
			})

			// 鼠标按下y轴滚动条后拖动
			dom.addeventlistener('mousemove', function (e) {
				if ( bydown && _this.byshow ) {
					var inowpagey = e.clienty + dom.documentelement.scrolltop || dom.body.scrolltop;
					var inowtop = iybartop + inowpagey - idownpagey;

					inowtop = inowtop <= 0 ? 0 : inowtop >= _this.iyboxh - _this.iybarh ? _this.iyboxh - _this.iybarh : inowtop;
					_this.iscrolltop = inowtop / _this.iyboxh * _this.iscrollh;
					_this.settranslate();
					_this.setytop(inowtop);
				}
			})

			// 禁止默认拖动事件
			this.oybar.ondrag = function (e) {
				var e = evt || win.event;
				evt ? e.preventdefault() : e.returnvalue = false;
			}
		}

		if ( this.bxbar ) {
			// 鼠标移上y轴滚动条变色
			if ( this.entercolor ) {
				this.oxbar.onmouseenter = function () {
					bxleave = false;
					setstyle(this, {
						backgroundcolor: _this.entercolor
					})
				}
				this.oxbar.onmouseleave = function () {
					bxleave = true;
					if ( !bxdown ) {
						setstyle(this, {
							backgroundcolor: _this.barcolor
						})
					}
				}
			}

			// 鼠标在x轴滚动条按下
			this.oxbar.onmousedown = function (e) {
				if ( _this.bxshow ) {
					bxdown = true;
					idownpagex = e.clientx + dom.documentelement.scrollleft || dom.body.scrollleft;
					ixbarleft = parseint(getstyle(this, 'left'));

					// 禁止文本可选中
	    			canselecttext(false);
				}
			}

			// 鼠标在按下x轴滚动条后抬起
			dom.addeventlistener('mouseup', function () {
				if ( bxdown && _this.bxshow ) {
					bxdown = false;
					// 恢复文本可选中
	    			canselecttext(true);

	    			if ( !isinwrapper && _this.entershow ) {
	    				setstyle(_this.oxbox, {
	    					display: 'none'
	    				})
	    			}
	    		}

	    		if ( !bxdown && bxleave ) {
	    			setstyle(_this.oxbar, {
	    				backgroundcolor: _this.barcolor
	    			})
	    		}
			})

			// 鼠标按下x轴滚动条后拖动
			dom.addeventlistener('mousemove', function (e) {
				if ( bxdown && _this.bxshow ) {
					var inowpagex = e.clientx + dom.documentelement.scrollleft || dom.body.scrollleft;
					var inowleft = ixbarleft + inowpagex - idownpagex;

					inowleft = inowleft <= 0 ? 0 : inowleft >= _this.ixboxw - _this.ixbarw ? _this.ixboxw - _this.ixbarw : inowleft;
					_this.iscrollleft = inowleft / _this.ixboxw * _this.iscrollw;
					_this.settranslate();
					_this.setxleft(inowleft);
				}
			})

			// 禁止默认拖动事件
			this.oxbar.ondrag = function (e) {
				var e = evt || win.event;
				evt ? e.preventdefault() : e.returnvalue = false;
			}
		}	
	}

	// 设置默认参数
	myscrollbar.prototype.setparam = function (o) {
		this.width = o.width ? o.width : 10;					// 滚动条的宽度

		this.bgcolor = o.bgcolor ? o.bgcolor : '#eaeaea';		// 滚动条背景颜色

		this.barcolor = o.barcolor ? o.barcolor : '#ccc';		// 滚动条颜色

		this.entercolor = o.entercolor || false;			// 鼠标移上滚动条时的颜色

		this.entershow = o.entershow === false ? false : true;	// 是否进入包裹层在显示滚动条

		this.hasy = o.hasy === false ? false : true;			// 是否有y轴滚动条

		this.hasx = o.hasx === true ? true : false;				// 是否有x轴滚动条

		this.borderradius = o.borderradius >= 0 ? o.borderradius : this.width / 2;	// 圆角
	}

	// 判断是否添加xy轴滚动条
	myscrollbar.prototype.addscrollbar = function () {
		// 获取包裹层与滚动层的尺寸
		this.getsize();

		if ( this.iwrapperw <= this.iscrollw && this.hasx ) {
			this.bxbar = true;
			
			this.oxbox = dom.createelement('div');					// x轴滚动条盒子
			this.oxbar = dom.createelement('div');					// x轴滚动条

			this.oxbox.appendchild(this.oxbar);						// 滚动条插入滚动条盒子
			this.owrapper.insertbefore(this.oxbox, this.oscroll);	// 滚动条盒子插到oscroll之前
		}

		if ( this.iwrapperh <= this.iscrollh && this.hasy ) {
			this.bybar = true;
			
			this.oybox = dom.createelement('div');					// x轴滚动条盒子
			this.oybar = dom.createelement('div');					// x轴滚动条

			this.oybox.appendchild(this.oybar);						// 滚动条插入滚动条盒子
			this.owrapper.insertbefore(this.oybox, this.oscroll);	// 滚动条盒子插到oscroll之前
		}
	}

	// 更新/获取包裹层与滚动层的尺寸
	myscrollbar.prototype.getsize = function () {
		var owrappersize = getclientsize(this.owrapper);
		var oscrollsize = getclientsize(this.oscroll);

		this.iwrapperclientw = owrappersize.width;
		this.iwrapperclienth = owrappersize.height;

		this.ipaddingt = parseint(getstyle(this.owrapper, 'paddingtop'));
		this.ipaddingr = parseint(getstyle(this.owrapper, 'paddingright'));
		this.ipaddingb = parseint(getstyle(this.owrapper, 'paddingbottom'));
		this.ipaddingl = parseint(getstyle(this.owrapper, 'paddingleft'));

		this.iwrapperw = owrappersize.width - this.ipaddingr - this.ipaddingl;
		this.iwrapperh = owrappersize.height - this.ipaddingt - this.ipaddingb;
		this.iscrollw = oscrollsize.width;
		this.iscrollh = oscrollsize.height;

		if ( this.bybar ) {
			this.iyboxh = owrappersize.height;
			this.iybarh = this.iwrapperh / this.iscrollh * this.iyboxh;
		}

		if ( this.bxbar ) {
			this.ixboxw = owrappersize.width;
			this.ixbarw = this.iwrapperw /this.iscrollw * this.ixboxw;
		}
	}

	// 设置尺寸
	myscrollbar.prototype.setsize = function () {
		// 更新包裹层与滚动层的尺寸
		this.getsize();

		if ( this.bybar ) {
			if ( this.iwrapperh >= this.iscrollh ) {
				setstyle(this.oybox, {
					display: 'none'
				})
				this.byshow = false;
			} else {
				if ( !this.entershow ) {
					setstyle(this.oybox, {
						display: 'block'
					})
				}
				setstyle(this.oybar, {
					height: this.iybarh + 'px',
					top: 0
				})
				this.byshow = true;
			}
		}

		if ( this.bxbar ) {
			if ( this.iwrapperw >= this.iscrollw ) {
				setstyle(this.oxbox, {
					display: 'none'
				})
				this.bxshow = false;
			} else {
				if ( !this.entershow ) {
					setstyle(this.oxbox, {
						display: 'block'
					})
				}
				setstyle(this.oxbar, {
					width: this.ixbarw + 'px',
					left: 0
				})
				this.bxshow = true;
			}
		}

		this.iscrolltop = 0;
		this.iscrollleft = 0;
		this.settranslate();
	}

	/**
	 * 作用：设置oscroll的位置转换transform:translate
	 * itime -> 动画时间，大于0有效，否则无动画，毫秒
	 */ 
	myscrollbar.prototype.settranslate = function (itime) {
		var stranslate = 'translate(-' + this.iscrollleft + 'px, -' + this.iscrolltop + 'px)';
		setstyle(this.oscroll, {
			transition: itime >= 0 ? itime + 'ms ease-in-out' : 0 + 'ms',
			transform: stranslate,
			mstransform: stranslate,
			moztransform: stranslate,
			webkittransform: stranslate,
			otransform: stranslate
		})
	}

	// 设置滚动top
	myscrollbar.prototype.setytop = function (itop, itime) {
		setstyle(this.oybar, {
			transition: itime >= 0 ? itime + 'ms ease-in-out' : 0 + 'ms',
			top: itop + 'px'
		})
	}

	// 设置滚动left
	myscrollbar.prototype.setxleft = function (ileft, itime) {
		setstyle(this.oxbar, {
			transition: itime >= 0 ? itime + 'ms ease-in-out' : 0 + 'ms',
			left: ileft + 'px'
		})
	}

	/**
	 * 作用：跳到指定位置
	 * o.id -> 要跳到那个id的位置；
	 * o.pos -> 要跳到那个具体的位置，如果为字符串（两个选中择'top','bottom'，'left'，'right')，
	 如果为对象（{top: number, left: number}），为对象时如果要y轴滚动条滚动就设置top，要两个轴一起滚动才一起设置。
	 * o.time -> 动画时间，不设没有动画
	 * 注：如果id存在，则pos不生效
	 */
	myscrollbar.prototype.jump = function (o) {
		var opos = {top: 0, left: 0};
		var itop = 0;
		var ibottome = this.iscrollh - this.iwrapperclienth + this.ipaddingt + this.ipaddingb > 0 ? this.iscrollh - this.iwrapperclienth + this.ipaddingt + this.ipaddingb : 0;
		var ileft = 0;
		var iright = this.iscrollw - this.iwrapperclientw + this.ipaddingl + this.ipaddingr > 0 ? this.iscrollw - this.iwrapperclientw + this.ipaddingl + this.ipaddingr : 0;

		if ( o.id ) {
			var obj = document.getelementbyid(o.id);
			opos = getposition(obj, this.oscroll);
			
			if ( this.bybar ) {
				opos.top += this.ipaddingt;
			}

			if ( this.bxbar ) {
				opos.left += this.ipaddingl;
			}
		} else if ( o.pos ) {
			if ( typeof o.pos == 'string' ) {
				switch(o.pos) {
					case 'top': opos.top = itop; break;
					case 'bottom': opos.top = ibottome; break;
					case 'left': opos.left = ileft; break;
					case 'right': opos.left = iright; break;
					default: break;
				}
			} else if ( typeof o.pos == 'object' ) {
				opos = o.pos;
			}
		}

		opos.top = opos.top > ibottome ? ibottome : opos.top >= 0 ? opos.top : 0;
		opos.left = opos.left > iright ? iright : opos.left >= 0 ? opos.left : 0;

		this.iscrolltop = opos.top;
		this.iscrollleft = opos.left;
		this.settranslate(o.time || 0);
		if ( this.bybar ) {
			this.setytop(this.iscrolltop / this.iscrollh * this.iyboxh, o.time || 0);
		}
		if ( this.bxbar ) {
			this.setxleft(this.iscrollleft / this.iscrollw * this.ixboxw, o.time || 0);
		}
	}

	// 获取样式
	function getstyle (obj, name) {
		if(win.getcomputedstyle) {
			return getcomputedstyle(obj, null)[name];
		} else {
			return obj.currentstyle[name];
		}
	}

	// 设置样式
	function setstyle (obj, ostyle) {
        for(var i in ostyle) {
            obj.style[i] = ostyle[i];
        }
    }

	/**
	 * 作用：获取对象的offset（内容尺寸+padding+border）尺寸，display:none;元素也可以获取
	 * 参数：obj -> 要获取尺寸的元素
	 * 返回：res -> width 宽; res -> height 高
	 * 依赖：getstyle，setstyle
	 */
	function getoffsetsize (obj) {
	    var sdisplay = getstyle(obj, "display");
	    var res = {}

	    if ( sdisplay != "none" ) {
	        res.width = obj.offsetwidth;
	        res.height = obj.offsetheight;
	    } else {
	        var oldstyle = {
	            position: getstyle(obj, "position"),
	            visibility: getstyle(obj, "visibility"),
	            display: sdisplay
	        }
	        var newstyle = {
	            position: "absolute",
	            visibility: "hidden",
	            display: "inline-block"
	        }
	        setstyle(obj, newstyle);
	        res.width = obj.offsetwidth;
	        res.height = obj.offsetheight;
	        setstyle(obj, oldstyle);
	    }
	    return res;
	}

	// 计算实际内容+padding宽高即clientwidth/clientheight，但ie时client包含边框
	function getclientsize (obj) {
		var itopw = parseint(getstyle(obj, 'bordertopwidth'));
		var irightw = parseint(getstyle(obj, 'borderrightwidth'));
		var ibottomw = parseint(getstyle(obj, 'borderbottomwidth'));
		var ileftw = parseint(getstyle(obj, 'borderleftwidth'));

		var ooffset = getoffsetsize(obj);
		return {
			width: ooffset.width <= 0 ? ooffset.width : ooffset.width - ileftw - irightw,
			height: ooffset.height <= 0 ? ooffset.height : ooffset.height - itopw - ibottomw
		}
	}

	// 禁止与恢复文本可选中,true为可选中，false为不可选中
	function canselecttext (bcan) {
		if ( !bcan ) {
			dom.body.style.mozuserselect = 'none';
			dom.body.style.webkituserselect = 'none';
			dom.body.style.msuserselect = 'none';
			dom.body.style.khtmluserselect = 'none';
			dom.body.style.userselect = 'none';
		} else {
			dom.body.style.mozuserselect = 'text';
			dom.body.style.webkituserselect = 'text';
			dom.body.style.msuserselect = 'text';
			dom.body.style.khtmluserselect = 'text';
			dom.body.style.userselect = 'text';
		}
	}

	/**
	 * 作用：获取obj到目标goal的position距离
	 */
	function getposition (obj, goal) {
		var opos = {
			top: obj.offsettop,
			left: obj.offsetleft
		}

		if ( obj.parentnode != goal ) {
			var obj = getposition(obj.parentnode, goal);
			opos.top += obj.top;
			opos.left += obj.left;
		} else {
			return opos;
		}
	}

	if ( typeof define === "function" && define.amd ) {
		define([], function () {
			return myscrollbar;
		});
	}
	win.myscrollbar = myscrollbar;
})(window, document);