JSFiddle - React, Tailwind, and code Playground

by Ayri Rin

JavaScript

var i;
        var currentdate = new Date();

        var months = new Array( "Январь", "Февраль", "Март", "Апрель", "Май", "Июнь",
                       "Июль", "Август", "Сентябрь", "Октябрь", "Ноябрь", "Декабрь" );
        var weekday = new Array( "Пн", "Вт", "Ср", "Чт", "Пт", "Сб", "Вс" );

        var currentmonth = currentdate.getMonth();
        for(i=0;i<12;i++) {
            if( document.location.href.indexOf( encodeURIComponent(months[i]) ) != -1 ) {
                currentmonth = i;
            }
        }

        var currentyear  = currentdate.getFullYear();
        for(i=1900;i<2100;i++)
            if( document.location.href.indexOf( (new Number(i)).toString() ) != -1 )
                currentyear = i;

        var monthcountday = new Array( 31, (((currentyear%4) == 0 ) ? 29 : 28), 
                                       31, 30, 31, 30, 31, 31, 30, 31, 30 ,31 );
          
        var firstday = ((new Date(currentyear,currentmonth,1)).getDay()+6)%7;

        document.write( "<h1 style='text-align:center'>Календарь</h1>"
                        + "<div align='center'>"
                        
                        + "<div><a href='calendar.html?"+encodeURIComponent(months[currentmonth])+","+(currentyear-1)+"'>"+(currentyear-1)+"</A>&nbsp;&nbsp;&nbsp;&nbsp;" 
                        + "<strong>" + currentyear + "</strong>"
                        + "&nbsp;&nbsp;&nbsp;&nbsp;<a href='calendar.html?"+encodeURIComponent(months[currentmonth])+","+(currentyear+1)+"'>"+(currentyear+1)+"</a></div>"

                        + ((currentmonth!=0) ? "<div><a href='calendar.html?"+encodeURIComponent(months[currentmonth-1])+","+currentyear+"'>"+months[currentmonth-1]+"</a>&nbsp;&nbsp;&nbsp;&nbsp;" 
                                             : "<div><a href='calendar.html?"+encodeURIComponent(months[11])+","+(currentyear-1)+"'>"+months[11]+" of "+(currentyear-1)+"</A>&nbsp;&nbsp;&nbsp;&nbsp;")
                        + "<strong>" + months[currentmonth] +...