(function(root, factory) {
    if (typeof define === 'function' && define.amd) {
        define('calendar', ['jquery'], factory);
    } else if (typeof exports === 'object') {
        module.exports = factory(require('jquery'));
    } else {
        factory(root.jquery);
    }
}(this, function($) {

    // default config

    var defaults = {

            // 宽度
            width: 280,
            // 高度, 不包含头部，头部固定高度
            height: 280,

            zindex: 1,

            // selector or element
            // 设置触发显示的元素，为null时默认显示
            trigger: null,

            // 偏移位置，可设正负值
            // trigger 设置时生效
            offset: [0, 1],

            // 自定义类，用于重写样式
            customclass: '',

            // 显示视图
            // 可选：date, month
            view: 'date',

            // 默认日期为当前日期
            date: new date(),
            format: 'yyyy/mm/dd',

            // 一周的第一天
            // 0表示周日，依次类推
            startweek: 0,

            // 星期格式
            weekarray: ['日', '一', '二', '三', '四', '五', '六'],

            // 设置选择范围
            // 格式：[开始日期, 结束日期]
            // 开始日期为空，则无上限；结束日期为空，则无下限
            // 如设置2015年11月23日以前不可选：[new date(), null] or ['2015/11/23']
            selectedrang: null,

            // 日期关联数据 [{ date: string, value: object }, ... ]
            // 日期格式与 format 一致
            // 如 [ {date: '2015/11/23', value: '面试'} ]
            data: null,

            // 展示关联数据
            // 格式化参数：{m}视图，{d}日期，{v}value
            // 设置 false 表示不显示
            label: '{d}\n{v}',

            // 切换字符
            prev: '<',
            next: '>',

            // 切换视图
            // 参数：view, y, m
            viewchange: $.noop,

            // view: 视图
            // date: 不同视图返回不同的值
            // value: 日期关联数据
            onselected: function(view, date, value) {
                // body...
            },

            // 参数同上
            onmouseenter: $.noop,

            onclose: $.noop
        },

        // static variable

        action_namespace = 'data-calendar-',

        display_vd = '[' + action_namespace + 'display-date]',
        display_vm = '[' + action_namespace + 'display-month]',

        arrow_date = '[' + action_namespace + 'arrow-date]',
        arrow_month = '[' + action_namespace + 'arrow-month]',

        item_day = action_namespace + 'day',
        item_month = action_namespace + 'month',

        disabled = 'disabled',
        mark_data = 'markdata',

        view_class = {
            date: 'calendar-d',
            month: 'calendar-m'
        },

        old_day_class = 'old',
        new_day_class = 'new',
        today_class = 'now',
        select_class = 'selected',
        mark_day_html = '<i class="dot"></i>',
        date_dis_tpl = '{year}/<span class="m">{month}</span>',

        item_style = 'style="width:{w}px;height:{h}px;line-height:{h}px"',
        week_item_tpl = '<li ' + item_style + '>{wk}</li>',
        day_item_tpl = '<li ' + item_style + ' class="{class}" {action}>{value}</li>',
        month_item_tpl = '<li ' + item_style + ' ' + item_month + '>{m}月</li>',

        template = [
            '<div class="calendar-inner">',
            '<div class="calendar-views">',
            '<div class="view view-date">',
            '<div class="calendar-hd">',
            '<a href="javascript:;" data-calendar-display-date class="calendar-display">',
            '{yyyy}/<span class="m">{mm}</span>',
            '</a>',
            '<div class="calendar-arrow">',
            '<span class="prev" title="上一月" data-calendar-arrow-date>{prev}</span>',
            '<span class="next" title="下一月" data-calendar-arrow-date>{next}</span>',
            '</div>',
            '</div>',
            '<div class="calendar-ct">',
            '<ol class="week">{week}</ol>',
            '<ul class="date-items"></ul>',
            '</div>',
            '</div>',
            '<div class="view view-month">',
            '<div class="calendar-hd">',
            '<a href="javascript:;" data-calendar-display-month class="calendar-display">{yyyy}</a>',
            '<div class="calendar-arrow">',
            '<span class="prev" title="上一年" data-calendar-arrow-month>{prev}</span>',
            '<span class="next" title="下一年" data-calendar-arrow-month>{next}</span>',
            '</div>',
            '</div>',
            '<ol class="calendar-ct month-items">{month}</ol>',
            '</div>',
            '</div>',
            '</div>',
            '<div class="calendar-label"><p>helloworld</p><i></i></div>'
        ],
        os = object.prototype.tostring;

    // utils

    function isdate(obj) {
        return os.call(obj) === '[object date]';
    }

    function isstring(obj) {
        return os.call(obj) === '[object string]';
    }


    function getclass(el) {
        return el.getattribute('class') || el.getattribute('classname');
    }

    // extension methods

    string.prototype.repeat = function(data) {
        return this.replace(/\{\w+\}/g, function(str) {
            var prop = str.replace(/\{|\}/g, '');
            return data[prop] || '';
        });
    }

    string.prototype.todate = function() {
        var dt = new date(),
            dot = this.replace(/\d/g, '').charat(0),
            arr = this.split(dot);

        dt.setfullyear(arr[0]);
        dt.setmonth(arr[1] - 1);
        dt.setdate(arr[2]);
        return dt;
    }

    date.prototype.format = function(exp) {
        var y = this.getfullyear(),
            m = this.getmonth() + 1,
            d = this.getdate();

        return exp.replace('yyyy', y).replace('mm', m).replace('dd', d);
    }

    date.prototype.issame = function(y, m, d) {
        if (isdate(y)) {
            var dt = y;
            y = dt.getfullyear();
            m = dt.getmonth() + 1;
            d = dt.getdate();
        }
        return this.getfullyear() === y && this.getmonth() + 1 === m && this.getdate() === d;
    }

    date.prototype.add = function(n) {
        this.setdate(this.getdate() + n);
    }

    date.prototype.minus = function(n) {
        this.setdate(this.getdate() - n);
    }

    date.prototype.cleartime = function(n) {
        this.sethours(0);
        this.setseconds(0);
        this.setminutes(0);
        this.setmilliseconds(0);
        return this;
    }

    date.isleap = function(y) {
        return (y % 100 !== 0 && y % 4 === 0) || (y % 400 === 0);
    }

    date.getdaysnum = function(y, m) {
        var num = 31;

        switch (m) {
            case 2:
                num = this.isleap(y) ? 29 : 28;
                break;
            case 4:
            case 6:
            case 9:
            case 11:
                num = 30;
                break;
        }
        return num;
    }

    date.getsiblingsmonth = function(y, m, n) {
        var d = new date(y, m - 1);
        d.setmonth(m - 1 + n);
        return {
            y: d.getfullyear(),
            m: d.getmonth() + 1
        };
    }

    date.getprevmonth = function(y, m, n) {
        return this.getsiblingsmonth(y, m, 0 - (n || 1));
    }

    date.getnextmonth = function(y, m, n) {
        return this.getsiblingsmonth(y, m, n || 1);
    }

    date.tryparse = function(obj) {
        if (!obj) {
            return obj;
        }
        return isdate(obj) ? obj : obj.todate();
    }


    // calendar class

    function calendar(element, options) {
        this.$element = $(element);
        this.options = $.extend({}, $.fn.calendar.defaults, options);
        this.$element.addclass('calendar ' + this.options.customclass);
        this.width = this.options.width;
        this.height = this.options.height;
        this.date = this.options.date;
        this.selectedrang = this.options.selectedrang;
        this.data = this.options.data;
        this.init();
    }

    calendar.prototype = {
        constructor: calendar,
        getdayaction: function(day) {
            var action = item_day;
            if (this.selectedrang) {
                var start = date.tryparse(this.selectedrang[0]),
                    end = date.tryparse(this.selectedrang[1]);

                if ((start && day < start.cleartime()) || (end && day > end.cleartime())) {
                    action = disabled;
                }
            }

            return action;
        },
        getdaydata: function(day) {
            var ret, data = this.data;

            if (data) {

                for (var i = 0, len = data.length; i < len; i++) {
                    var item = data[i];

                    if (day.issame(item.date.todate())) {
                        ret = item.value;
                    }
                }
            }

            return ret;
        },
        getdayitem: function(y, m, d, f) {
            var dt = this.date,
                idt = new date(y, m - 1, d),
                data = {
                    w: this.width / 7,
                    h: this.height / 7,
                    value: d
                },
                markdata,
                $item;

            var selected = dt.issame(y, m, d) ? select_class : '';
            if (f === 1) {
                data['class'] = old_day_class;
            } else if (f === 3) {
                data['class'] = new_day_class;
            } else {
                data['class'] = '';
            }

            if (dt.issame(y, m, d)) {
                data['class'] += ' ' + today_class;
            }

            data.action = this.getdayaction(idt);
            markdata = this.getdaydata(idt);

            $item = $(day_item_tpl.repeat(data));

            if (markdata) {
                $item.data(mark_data, markdata);
                $item.html(d + mark_day_html);
            }

            return $item;
        },
        getdayshtml: function(y, m) {
            var year, month, firstweek, daysnum, prevm, prevdiff,
                dt = this.date,
                $days = $('<ol class="days"></ol>');

            if (isdate(y)) {
                year = y.getfullyear();
                month = y.getmonth() + 1;
            } else {
                year = number(y);
                month = number(m);
            }

            firstweek = new date(year, month - 1, 1).getday() || 7;
            prevdiff = firstweek - this.options.startweek;
            daysnum = date.getdaysnum(year, month);
            prevm = date.getprevmonth(year, month);
            prevdaysnum = date.getdaysnum(year, prevm.m);
            nextm = date.getnextmonth(year, month);
            // month flag
            var prev_flag = 1,
                curr_flag = 2,
                next_flag = 3,
                count = 0;

            for (var p = prevdaysnum - prevdiff + 1; p <= prevdaysnum; p++, count++) {

                $days.append(this.getdayitem(prevm.y, prevm.m, p, prev_flag));
            }

            for (var c = 1; c <= daysnum; c++, count++) {
                $days.append(this.getdayitem(year, month, c, curr_flag));
            }

            for (var n = 1, nl = 42 - count; n <= nl; n++) {

                $days.append(this.getdayitem(nextm.y, nextm.m, n, next_flag));
            }

            return $('<li></li>').width(this.options.width).append($days);
        },
        getweekhtml: function() {
            var week = [],
                weekarray = this.options.weekarray,
                start = this.options.startweek,
                len = weekarray.length,
                w = this.width / 7,
                h = this.height / 7;

            for (var i = start; i < len; i++) {
                week.push(week_item_tpl.repeat({
                    w: w,
                    h: h,
                    wk: weekarray[i]
                }));
            }

            for (var j = 0; j < start; j++) {
                week.push(week_item_tpl.repeat({
                    w: w,
                    h: h,
                    wk: weekarray[j]
                }));
            }

            return week.join('');
        },
        getmonthhtml: function() {
            var month = [],
                w = this.width / 4,
                h = this.height / 4,
                i = 1;

            for (; i < 13; i++) {
                month.push(month_item_tpl.repeat({
                    w: w,
                    h: h,
                    m: i
                }));
            }

            return month.join('');
        },
        setmonthaction: function(y) {
            var m = this.date.getmonth() + 1;

            this.$monthitems.children().removeclass(today_class);
            if (y === this.date.getfullyear()) {
                this.$monthitems.children().eq(m - 1).addclass(today_class);
            }
        },
        fillstatic: function() {
            var staticdata = {
                prev: this.options.prev,
                next: this.options.next,
                week: this.getweekhtml(),
                month: this.getmonthhtml()
            };

            this.$element.html(template.join('').repeat(staticdata));
        },
        updatedisdate: function(y, m) {
            this.$disdate.html(date_dis_tpl.repeat({
                year: y,
                month: m
            }));
        },
        updatedismonth: function(y) {
            this.$dismonth.html(y);
        },
        filldateitems: function(y, m) {
            var ma = [
                date.getprevmonth(y, m), {
                    y: y,
                    m: m
                },
                date.getnextmonth(y, m)
            ];

            this.$dateitems.html('');
            for (var i = 0; i < 3; i++) {
                var $item = this.getdayshtml(ma[i].y, ma[i].m);
                this.$dateitems.append($item);
            }

        },
        hide: function(view, date, data) {
            this.$trigger.val(date.format(this.options.format));
            this.options.onclose.call(this, view, date, data);
            this.$element.hide();
        },
        trigger: function() {

            this.$trigger = this.options.trigger instanceof $ ? this.options.trigger : $(this.options.trigger);

            var _this = this,
                $this = _this.$element,
                post = _this.$trigger.offset(),
                offs = _this.options.offset;

            $this.addclass('calendar-modal').css({
                left: (post.left + offs[0]) + 'px',
                top: (post.top + _this.$trigger.outerheight() + offs[1]) + 'px',
                zindex: _this.options.zindex
            });

            _this.$trigger.click(function() {
                $this.show();
            });

            $(document).click(function(e) {
                if (_this.$trigger[0] != e.target && !$.contains($this[0], e.target)) {
                    $this.hide();
                }
            });
        },
        render: function() {
            this.$week = this.$element.find('.week');
            this.$dateitems = this.$element.find('.date-items');
            this.$monthitems = this.$element.find('.month-items');
            this.$label = this.$element.find('.calendar-label');
            this.$disdate = this.$element.find(display_vd);
            this.$dismonth = this.$element.find(display_vm);

            var y = this.date.getfullyear(),
                m = this.date.getmonth() + 1;

            this.updatedisdate(y, m);
            this.updatemonthview(y);

            this.filldateitems(y, m);

            this.options.trigger && this.trigger();

        },
        setview: function(view) {
            this.$element.removeclass(view_class.date + ' ' + view_class.month)
                .addclass(view_class[view]);
            this.view = view;
        },
        updatedateview: function(y, m, dirc, cb) {
            m = m || this.date.getmonth() + 1;

            var _this = this,
                $dis = this.$dateitems,
                exec = {
                    prev: function() {
                        var pm = date.getprevmonth(y, m),
                            ppm = date.getprevmonth(y, m, 2),
                            $previtem = _this.getdayshtml(ppm.y, ppm.m);

                        m = pm.m;
                        y = pm.y;

                        $dis.animate({
                            marginleft: 0
                        }, 300, 'swing', function() {
                            $dis.children(':last').remove();
                            $dis.prepend($previtem).css('margin-left', '-100%');

                            $.isfunction(cb) && cb.call(_this);
                        });
                    },
                    next: function() {
                        var nm = date.getnextmonth(y, m),
                            nnm = date.getnextmonth(y, m, 2),
                            $nextitem = _this.getdayshtml(nnm.y, nnm.m);

                        m = nm.m;
                        y = nm.y;

                        $dis.animate({
                            marginleft: '-200%'
                        }, 300, 'swing', function() {
                            $dis.children(':first').remove();
                            $dis.append($nextitem).css('margin-left', '-100%');

                            $.isfunction(cb) && cb.call(_this);
                        });

                    }
                };


            if (dirc) {
                exec[dirc]();
            } else {
                this.filldateitems(y, m);
            }

            this.updatedisdate(y, m);

            this.setview('date');

            return {
                y: y,
                m: m
            };
        },
        updatemonthview: function(y) {
            this.updatedismonth(y);
            this.setmonthaction(y);
            this.setview('month');
        },
        getdisdatevalue: function() {
            var arr = this.$disdate.html().split('/'),
                y = number(arr[0]),
                m = number(arr[1].match(/\d{1,2}/)[0]);

            return [y, m];
        },
        selectedday: function(d, type) {
            var arr = this.getdisdatevalue(),
                y = arr[0],
                m = arr[1],
                toggleclass = function() {
                    this.$dateitems.children(':eq(1)')
                        .find('[' + item_day + ']:not(.' + new_day_class + ', .' + old_day_class + ')')
                        .removeclass(select_class)
                        .filter(function(index) {
                            return parseint(this.innerhtml) === d;
                        }).addclass(select_class);
                };

            if (type) {
                var ret = this.updatedateview(y, m, {
                    'old': 'prev',
                    'new': 'next'
                }[type], toggleclass);
                y = ret.y;
                m = ret.m;
                this.options.viewchange('date', y, m);
            } else {
                toggleclass.call(this);
            }

            return new date(y, m - 1, d);
        },
        showlabel: function(event, view, date, data) {
            var $lbl = this.$label;

            $lbl.find('p').html(this.options.label.repeat({
                m: view,
                d: date.format(this.options.format),
                v: data
            }).replace(/\n/g, '<br>'));

            var w = $lbl.outerwidth(),
                h = $lbl.outerheight();

            $lbl.css({
                left: (event.pagex - w / 2) + 'px',
                top: (event.pagey - h - 20) + 'px'
            }).show();
        },
        haslabel: function() {
            if (this.options.label) {
                $('body').append(this.$label);
                return true;
            }
            return false;
        },
        event: function() {
            var _this = this,
                vc = _this.options.viewchange;

            // view change
            _this.$element.on('click', display_vd, function() {
                var arr = _this.getdisdatevalue();
                _this.updatemonthview(arr[0], arr[1]);

                vc('month', arr[0], arr[1]);

            }).on('click', display_vm, function() {
                var y = this.innerhtml;

                _this.updatedateview(y);
                vc('date', y);
            });

            // arrow
            _this.$element.on('click', arrow_date, function() {
                var arr = _this.getdisdatevalue(),
                    type = getclass(this),
                    y = arr[0],
                    m = arr[1];

                var d = _this.updatedateview(y, m, type, function() {
                    vc('date', d.y, d.m);
                });

            }).on('click', arrow_month, function() {

                var y = number(_this.$dismonth.html()),
                    type = getclass(this);

                y = type === 'prev' ? y - 1 : y + 1;
                _this.updatemonthview(y);
                vc('month', y);
            });

            // selected
            _this.$element.on('click', '[' + item_day + ']', function() {
                var d = parseint(this.innerhtml),
                    cls = getclass(this),
                    type = /new|old/.test(cls) ? cls.match(/new|old/)[0] : '';

                var day = _this.selectedday(d, type);

                _this.options.onselected.call(this, 'date', day, $(this).data(mark_data));

                _this.$trigger && _this.hide('date', day, $(this).data(mark_data));

            }).on('click', '[' + item_month + ']', function() {
                var y = number(_this.$dismonth.html()),
                    m = parseint(this.innerhtml);

                _this.updatedateview(y, m);
                vc('date', y, m);
                _this.options.onselected.call(this, 'month', new date(y, m - 1));
            });

            // hover
            _this.$element.on('mouseenter', '[' + item_day + ']', function(e) {
                var arr = _this.getdisdatevalue(),
                    day = new date(arr[0], arr[1] - 1, parseint(this.innerhtml));

                if (_this.haslabel && $(this).data(mark_data)) {
                    $('body').append(_this.$label);
                    _this.showlabel(e, 'date', day, $(this).data(mark_data));
                }

                _this.options.onmouseenter.call(this, 'date', day, $(this).data(mark_data));
            }).on('mouseleave', '[' + item_day + ']', function() {
                _this.$label.hide();
            });
        },
        resize: function() {
            var w = this.width,
                h = this.height,
                hdh = this.$element.find('.calendar-hd').outerheight();

            this.$element.width(w).height(h + hdh)
                .find('.calendar-inner, .view')
                .css('width', w + 'px');

            this.$element.find('.calendar-ct').width(w).height(h);

        },
        init: function() {

            this.fillstatic();
            this.resize();
            this.render();
            this.view = this.options.view;
            this.setview(this.view);
            this.event();
        },
        setdata: function(data) {
            this.data = data;

            if (this.view === 'date') {
                var d = this.getdisdatevalue();
                this.filldateitems(d[0], d[1]);
            } else if (this.view === 'month') {
                this.updatemonthview(this.$dismonth.html());
            }
        },
        methods: function(name, args) {
            if (os.call(this[name]) === '[object function]') {
                return this[name].apply(this, args);
            }
        }
    };

    $.fn.calendar = function(options) {
        var calendar = this.data('calendar'),
            fn,
            args = [].slice.call(arguments);

        if (!calendar) {
            return this.each(function() {
                return $(this).data('calendar', new calendar(this, options));
            });
        }
        if (isstring(options)) {
            fn = options;
            args.shift();
            return calendar.methods(fn, args);
        }

        return this;
    }

    $.fn.calendar.defaults = defaults;

}));