;(function ($, window, document, undefined) {
    'use strict';
    function paging(element, options) {
        this.element = element;
        this.options = {
            pagenum: options.pagenum || 1, // 当前页码
            totalnum: options.totalnum, // 总页码
            totallist: options.totallist, // 数据总记录
            callback: options.callback // 回调函数
        };
        this.init();
    }
    paging.prototype = {
        constructor: paging,
        init: function () {
            this.createhtml();
            this.bindevent();
        },
        createhtml: function () {
            var me = this;
            var content = [];
            var pagenum = me.options.pagenum;
            var totalnum = me.options.totalnum;
            var totallist = me.options.totallist;
            content.push("<button type='button' id='firstpage'>首页</button><button type='button' id='prepage'>上一页</button>");
            // 总页数大于6必显示省略号
            if (totalnum > 6) {
                // 1、当前页码小于5且总页码大于6 省略号显示后面+总页码
                if (pagenum < 5) {
                    // 1与6主要看要显示多少个按钮 目前都显示5个
                    for (var i = 1; i < 6; i++) {
                        if (pagenum !== i) {
                            content.push("<button type='button'>" + i + "</button>");
                        } else {
                            content.push("<button type='button' class='current'>" + i + "</button>");
                        }
                    }
                    content.push(". . .");
                    content.push("<button type='button'>" + totalnum + "</button>");
                } else {
                    // 2、当前页码接近后面 到最后页码隔3个 省略号显示后面+总页面
                    if (pagenum < totalnum - 3) {
                        for (var i = pagenum - 2; i < pagenum + 3; i++) {
                            if (pagenum !== i) {
                                content.push("<button type='button'>" + i + "</button>");
                            } else {
                                content.push("<button type='button' class='current'>" + i + "</button>");
                            }
                        }
                        content.push(". . .");
                        content.push("<button type='button'>" + totalnum + "</button>");
                    } else {
                        // 3、页码至少在5，最多在【totalnum - 3】的中间位置 第一页+省略号显示前面
                        content.push("<button type='button'>" + 1 + "</button>");
                        content.push(". . .");
                        for (var i = totalnum - 4; i < totalnum + 1; i++) {
                            if (pagenum !== i) {
                                content.push("<button type='button'>" + i + "</button>");
                            } else {
                                content.push("<button type='button' class='current'>" + i + "</button>");
                            }
                        }
                    }
                }
            } else {
                // 总页数小于6
                for (var i = 1; i < totalnum + 1; i++) {
                    if (pagenum !== i) {
                        content.push("<button type='button'>" + i + "</button>");
                    } else {
                        content.push("<button type='button' class='current'>" + i + "</button>");
                    }
                }
            }
            content.push("<button type='button' id='lastpage'>尾页</button><button type='button' id='nextpage'>下一页</button>");
            content.push("<span class='totalnum'> 共 " + totalnum + " 页 </span>");
            content.push("<span class='totallist'>  " + totallist + " 条记录 </span>");
            me.element.html(content.join(''));

            // dom重新生成后每次调用是否禁用button
            settimeout(function () {
                me.dis();
            }, 20);
        },
        bindevent: function () {
            var me = this;
            me.element.off('click', 'button');
            // 委托新生成的dom监听事件
            me.element.on('click', 'button', function () {
                var id = $(this).attr('id');
                var num = parseint($(this).html());
                var pagenum = me.options.pagenum;
                if (id === 'prepage') {
                    if (pagenum !== 1) {
                        me.options.pagenum -= 1;
                    }
                } else if (id === 'nextpage') {
                    if (pagenum !== me.options.totalnum) {
                        me.options.pagenum += 1;
                    }
                } else if (id === 'firstpage') {
                    if (pagenum !== 1) {
                        me.options.pagenum = 1;
                    }
                } else if (id === 'lastpage') {
                    if (pagenum !== me.options.totalnum) {
                        me.options.pagenum = me.options.totalnum;
                    }
                } else {
                    me.options.pagenum = num;
                }
                me.createhtml();
                if (me.options.callback) {
                    me.options.callback(me.options.pagenum);
                }
            });
        },
        dis: function () {
            var me = this;
            var pagenum = me.options.pagenum;
            var totalnum = me.options.totalnum;
            if (pagenum === 1) {
                me.element.children('#firstpage, #prepage').prop('disabled', true);
            } else if (pagenum === totalnum) {
                me.element.children('#lastpage, #nextpage').prop('disabled', true);
            }
        }
    };
    $.fn.paging = function (options) {
        return new paging($(this), options);
    }
})(jquery, window, document);