https://iot.ru/bitrix/templates/.default/components/m2m/news.calendar/events/calendar.js

1function Calendar(ajaxId, node, initMonth, initYear) {
2    var url;
3    var self = this;
4    this.currentMonth = initMonth;
5    this.currentYear = initYear;
6    node.addEventListener('click', calendarEventHandler, false);
7
8    function calendarEventHandler(event) {
9        var btnClassName = event.target.className;
10
11        if (~btnClassName.indexOf('calendar__button_prev-month')) {
12            if (!(self.currentMonth - 1)) {
13                url = getUrl(12, self.currentYear - 1);
14                self.currentMonth = 12;
15                self.currentYear--;
16            } else {
17                url = getUrl(self.currentMonth - 1, self.currentYear);
18                self.currentMonth--;
19            }
20            updateCalendar(url);
21        }
22
23        if (~btnClassName.indexOf('calendar__button_prev-year')) {
24            url = getUrl(self.currentMonth, self.currentYear - 1);
25            self.currentYear--;
26            updateCalendar(url);
27        }
28        if (~btnClassName.indexOf('calendar__button_next-month')) {
29            if (self.currentMonth == 12) {
30                url = getUrl(1, self.currentYear + 1);
31                self.currentMonth = 1;
32                self.currentYear++;
33            } else {
34                url = getUrl(self.currentMonth + 1, self.currentYear);
35                self.currentMonth++;
36            }
37            updateCalendar(url);
38        }
39        if (~btnClassName.indexOf('calendar__button_next-year')) {
40            url = getUrl(self.currentMonth, self.currentYear + 1);
41            self.currentYear++;
42            updateCalendar(url);
43        }
44        
45        var href = event.target.dataset.href || event.target.parentNode.dataset.href;
46        if (href) {
47            location.href = href;
48        }
49
50    }
51
52    function getUrl(month, year) {
53        return location.pathname + '?month=' + month + '&year=' + year + '&bxajaxid=' + ajaxId;
54    }
55
56    function updateCalendar(url) {
57        BX.ajax.insertToNode(url, 'comp_' + ajaxId);
58    }
59
60    return true;
61}