/*----使用说明

结构必需一致;多次调用时，最外层赋予不同的id或类名即可

*/

/*----参数

@ wrap [String] 外层元素的类名或id

@ auto [Boolean] 不设置默认是不自动播放；设置为true，自动播放

@ speed [Number] 每隔几秒图片切换，默认是4秒

*/

function Gy_slider(opt){

    this.wrap = $(opt.wrap);

    this.scroll = this.wrap.find('.gy-slide-scroll ul');

    this.li = this.scroll.find('li');

    this.btn_num = this.wrap.find('.gy-slide-btn span');

    this.btn_home = this.wrap.find('.gy-slide-home');

    this.btn_end = this.wrap.find('.gy-slide-end');

    this.btn_prev = this.wrap.find('.gy-slide-prev');

    this.btn_next = this.wrap.find('.gy-slide-next');

    this.index = 0; //索引

    this.refer = 0;

    this.ctrl = true;

    this.len = this.li.length;

    this.move_w = this.scroll.parent().width();

    this.auto = opt.auto == true?true:false;

    this.speed = opt.speed || 4;

    this.init();

}

Gy_slider.prototype = {

    imgShow:function(i,callback){

        var _that = this,

            _w = 0;

        switch(true){

            case i<this.refer : _w = - this.move_w;break;

            case i==this.refer : return;break;

            default:_w = this.move_w;

            }

        this.refer = i;

        this.li.eq(i).css({'position':'absolute','left':_w+'px','top':0});

        this.scroll.stop(true,true).animate({'left':-_w+'px'},function(){

            _that.scroll.css({'left':0});

            _that.li.attr('style','').eq(i).css({'position':'absolute','left':0,'top':0});

            if(typeof callback == 'function'){

                callback();

            }

        });

        this.btn_num.removeClass("gy-slide-cur").eq(i).addClass("gy-slide-cur");

    },

    isCtrl:function(n){

        this.btn_prev.add(this.btn_next).removeClass("gy-slide-no");

        if(n==0){

            this.btn_prev.addClass("gy-slide-no");

        }else if(n==(this.len-1)){

            this.btn_next.addClass("gy-slide-no");

        }

    },

    btnClick:function(){

        var _that = this;

        //页码处理

        this.btn_num.click(function(){

            if(_that.btn_num.index($(this))==_that.index) return;

            if(!_that.ctrl) return;

            _that.ctrl = false;

            _that.index = _that.btn_num.index($(this));

            _that.isCtrl(_that.index);

            _that.imgShow(_that.index,function(){

                _that.ctrl = true;

            });

        });

        //首页

        this.btn_home.click(function(){

            _that.index = 0;

            _that.isCtrl(_that.index);

            _that.imgShow(_that.index);

        });

        //尾页

        this.btn_end.click(function(){

            _that.index = _that.len - 1;

            _that.isCtrl(_that.index);

            _that.imgShow(_that.index);

        });

        //上一页

        this.btn_prev.click(function(){

            if($(this).hasClass("gy-slide-no")) return;

            if(!_that.ctrl) return;

            _that.ctrl = false;

            _that.index--;

            _that.isCtrl(_that.index);

            _that.imgShow(_that.index,function(){

                _that.ctrl = true;

            });

        });

        //下一页

        this.btn_next.click(function(){

            if($(this).hasClass("gy-slide-no")) return;

            if(!_that.ctrl) return;

            _that.ctrl = false;

            _that.index++;

            _that.isCtrl(_that.index);

            _that.imgShow(_that.index,function(){

                _that.ctrl = true;

            });

        });

    },

    autoPlay:function(){

        var _that = this;

        if(this.timer) clearInterval(this.timer);

        this.timer = setInterval(function(){

            _that.index++;

            if(_that.index==_that.len){

                _that.index = 0;

            }

            _that.isCtrl(_that.index);

            _that.imgShow(_that.index);

        },this.speed*1000);

    },

    init:function(){

        var _that = this;

        this.btnClick();

        if(this.auto){

            this.autoPlay();

            this.wrap.hover(function(){

                clearInterval(_that.timer);

            },function(){

                _that.autoPlay();

            });

        }

    }

}