(function ($) {
    $.fn.extend({
        Scroll: function (opt, callback) {
            //参数初始化
            if (!opt) var opt = {};
            var _btnUp = $("#" + opt.up); //Shawphy:向上按钮
            var _btnDown = $("#" + opt.down); //Shawphy:向下按钮
            var timerID;
            var _this = this.eq(0).find("ul:first");
            var lineH = _this.find("li:first").height(),
                //获取行高
                line = opt.line ? parseInt(opt.line, 10) : parseInt(this.height() / lineH, 10),
                //每次滚动的行数，默认为一屏，即父容器高度
                speed = opt.speed ? parseInt(opt.speed, 10) : 500; //卷动速度，数值越大，速度越慢（毫秒）
            timer = opt.timer //?parseInt(opt.timer,10):3000; //滚动的时间间隔（毫秒）
            if (line == 0) line = 1;
            var upHeight = 0 - line * lineH;
            //滚动函数
            var scrollUp = function () {
                _btnUp.unbind("click", scrollUp); //Shawphy:取消向上按钮的函数绑定
                _this.animate({
                    marginTop: upHeight
                }, speed, function () {
                    for (i = 1; i <= line; i++) {
                        _this.find("li:first").appendTo(_this);
                    }
                    _this.css({
                        marginTop: 0
                    });
                    _btnUp.bind("click", scrollUp); //Shawphy:绑定向上按钮的点击事件
                });

            }
            //Shawphy:向下翻页函数
            var scrollDown = function () {
                _btnDown.unbind("click", scrollDown);
                for (i = 1; i <= line; i++) {
                    _this.find("li:last").show().prependTo(_this);
                }
                _this.css({
                    marginTop: upHeight
                });
                _this.animate({
                    marginTop: 0
                }, speed, function () {
                    _btnDown.bind("click", scrollDown);
                });
            }
            //Shawphy:自动播放
            var autoPlay = function () {
                if (timer) timerID = window.setInterval(scrollUp, timer);
            };
            var autoStop = function () {
                if (timer) window.clearInterval(timerID);
            };
            //鼠标事件绑定
            _this.hover(autoStop, autoPlay).mouseout();
            _btnUp.css("cursor", "pointer").click(scrollUp).hover(autoStop, autoPlay); //Shawphy:向上向下鼠标事件绑定
            _btnDown.css("cursor", "pointer").click(scrollDown).hover(autoStop, autoPlay);
        }
    })
})(jQuery);

$(document).ready(function () {
    $("#scrollDiv").Scroll({
        line: 1,
        speed: 600,
        timer: 2500,
        up: "btn1",
        down: "btn2"
    });
    var msg = getQueryParam('msg');
    if(msg!='') alert(msg);
});

function getQueryParam(paramName) {
    paramName = paramName.toLowerCase();
    paramName += "=";
    var url = window.location.href.toString();
    var questMarkPos = url.indexOf("?");
    if (questMarkPos != -1) {
        var params = url.substr(questMarkPos + 1).split(/\&/g);
        for (var i = 0; i < params.length; i++) {
            var param = params[i];
            if (param.toLowerCase().indexOf(paramName) < 0) {
                continue;
            } else {
                return decodeURIComponent(param.substr(param.indexOf("=") + 1));
            }
        }
    }
    return "";
}