Making JetSmartFilters checkbox, radio, and visual filters more accessible

script.js

<script>
    var radioGroupClass='.jet-radio-list';
    var radioClass='.jet-radio-list__button';
    var radioInputClass='.jet-radio-list__input';

    var visualGroupClass='.jet-color-image-list';
    var visualClass='.jet-color-image-list__button';
    var visualInputClass='.jet-color-image-list__input';

    var checkboxGroupClass='.jet-checkboxes-list';
    var checkboxClass='.jet-checkboxes-list__button';
    var checkboxInputClass='.jet-checkboxes-list__input';

    jQuery(document).ready(function($ ) {
        filterRadioWidgetInit();
        filterCheckboxWidgetInit();
        filterVisualWidgetInit();

        $(document).on('jet-filter-content-rendered', function() {
            setTimeout(function () {
                filterRadioWidgetInit();
                filterCheckboxWidgetInit();
                filterVisualWidgetInit();
            }, 1);
        });

        ////////////////////////////////
        //  RADIO BUTTON
        function filterRadioWidgetInit() {

            $(radioGroupClass).each(function () {
                $(this).attr('role', 'radiogroup');

                $(this).find(radioClass).each(function () {
                    $(this).attr('role', 'radio');
                    initAttr(this, 'aria-checked');
                });

                if ($(this).find(radioClass + '.aria-checked').length > 0) {
                    $(this).find(radioClass).each(function () {
                        initTabIndex(this, 'aria-checked');
                    });
                }

                else {
                    $(this).find(radioClass).each(function () {
                        $(this).attr('tabindex', '-1');
                    });
                    $(this).find(radioClass).first().attr('tabindex', '0');
                }
            });

            $(radioClass).off('keydown').on('keydown', function(e) {
                            
                switch (e.which) {
                
                    case 37: 
                    case 38: 
                        e.preventDefault();
                        gotoPrevElement($(this), '.jet-filter-row', radioClass).focus();
                        break;
            
                    case 39: 
                    case 40: 
                        e.preventDefault();
                        gotoNextElement($(this), '.jet-filter-row', radioClass).focus();
                        break;
            
                    case 13: 
                    case 32: 
                        e.preventDefault();
                        var input=$(this).parent().find(radioInputClass);

                        // Reset aria-press for radios.  They will be reset after filter update
                        $(this).closest(radioGroupClass).find(radioClass).each(function() {
                            $(this).removeClass('aria-checked');
                            $(this).attr('aria-checked', 'false');
                            $(this).attr('tabindex', '-1');
                        });

                        $(this).attr('tabindex', '0');
                        simulateClick(this, input, 'aria-checked', 'checked');
                        break;
                }
            });

            $(radioClass).off('click').on('click', function() {
                var input=$(this).parent().find(radioInputClass);

                $(this).closest(radioGroupClass).find(radioClass).each(function() {
                    $(this).removeClass('aria-checked');
                    $(this).attr('aria-checked', 'false');
                    $(this).attr('tabindex', '-1');
                });
                $(this).attr('tabindex', '0');
                setClassAndAriaFromInput(this, input, 'checked', 'aria-checked');
            });
        }

        ////////////////////////////////
        //  CHECKBOX	
        function filterCheckboxWidgetInit() {
            $(checkboxGroupClass).each(function () {
                $(this).attr('role', 'group');
            });

            $(checkboxClass).each(function() {
                $(this).attr('role', 'checkbox');
                $(this).attr('tabindex', '0');
                initAttr(this, 'aria-checked');
            });

            $(checkboxClass).off('keydown').on('keydown', function(e) {
                switch (e.which) {
                    case 37: 
                    case 38: 
                        e.preventDefault();
                        gotoPrevElement($(this), '.jet-filter-row', checkboxClass).focus();
                        break;
                    case 39: 
                    case 40: 
                        e.preventDefault();
                        gotoNextElement($(this), '.jet-filter-row', checkboxClass).focus();
                        break;
                    case 13: 
                    case 32: 
                        e.preventDefault();
                        var input=$(this).parent().find(checkboxInputClass);
                        simulateClick(this, input, 'aria-checked', 'checked');
                        break;
                }
            });

            $(checkboxClass).off('click').on('click', function() {
                var input=$(this).parent().find(checkboxInputClass);
                setClassAndAriaFromInput(this, input, 'checked', 'aria-checked');
            });

        }


        ////////////////////////////////
        //  VISUAL FILTER
        function filterVisualWidgetInit() {

            $(visualGroupClass).each(function () {
                $(this).attr('role', 'radiogroup');

                $(this).find(visualClass).each(function () {
                    $(this).attr('role', 'radio');
                    initAttr(this, 'aria-checked');
                });

                if ($(this).find(visualClass + '.aria-checked').length > 0) {
                    $(this).find(radioClass).each(function () {
                        initTabIndex(this, 'aria-checked');
                    });
                } else {
                    $(this).find(visualClass).each(function () {
                        $(this).attr('tabindex', '-1');
                    });
                    $(this).find(visualClass).first().attr('tabindex', '0');
                }
            });

        $(visualClass).off('keydown').on('keydown', function(e) {
            switch (e.which) {
                case 37: 
                case 38: 
                    e.preventDefault();
                    gotoPrevElement($(this), '.jet-filter-row', visualClass).focus();
                    break;
                case 39: 
                case 40: 
                    e.preventDefault();
                    gotoNextElement($(this), '.jet-filter-row', visualClass).focus();
                    break;
                case 13: 
                case 32: 
                    e.preventDefault();
                    var input=$(this).parent().find(visualInputClass);

                    // Reset aria-press for radios.  They will be reset after filter update
                    $(this).closest(visualGroupClass).find(visualClass).each(function() {
                        $(this).removeClass('aria-checked');
                        $(this).attr('aria-checked', 'false');
                        $(this).attr('tabindex', '-1');
                    });

                    $(this).attr('tabindex', '0');
                    simulateClick(this, input, 'aria-checked', 'checked');
                    break;
            }
        });

        $(visualClass).off('click').on('click', function() {
            var input=$(this).parent().find(visualInputClass);

            $(this).closest(visualGroupClass).find(visualClass).each(function() {
                $(this).removeClass('aria-checked');
                $(this).attr('aria-checked', 'false');
                $(this).attr('tabindex', '-1');
            });
            $(this).attr('tabindex', '0');
            setClassAndAriaFromInput(this, input, 'checked', 'aria-checked');
            });
        }

        //////////////////// SUPPORT FUNCTIONS ////////////////////////////

        function gotoNextElement(t, closestElem, findElem) {
            var next=t.closest(closestElem).next()[0];

            if (next===undefined) {
                next = t.closest(closestElem).prevAll().last()[0];
            }

            if (next !==undefined) {
                return $(next).find(findElem);
            }

            return undefined;
        }

        function gotoPrevElement(t, closestElem, findElem) {
            var prev=t.closest(closestElem).prev()[0];

            if (prev===undefined) {
                prev = t.closest(closestElem).nextAll().last()[0];
            }

            if (prev !==undefined) {
                return $(prev).find(findElem);
            }

            return undefined;
        }

        function initTabIndex(t, attr) {
            if ($(t).hasClass(attr)) {
                $(t).attr('tabindex', '0');
            } else {
                $(t).attr('tabindex', '-1');
            }
        }

        function initAttr(t, attr) {
            if ($(t).hasClass(attr)) {
                $(t).attr(attr, 'true');
            } else {
                $(t).attr(attr, 'false');
            }
        }

        function simulateClick(t, input, attr, prop) {
            setClassAndAriaFromInput(t, input, prop, attr);
            input.trigger('click');
        }

        function setClassAndAriaFromInput(t, input, prop, attr) {
            if (input.prop(prop)===true) {
                $(t).removeClass(attr);
                $(t).attr(attr, 'false');
            } else {
                $(t).attr(attr, 'true');
                $(t).addClass(attr);
            }
        }

    });
</script>

Does not support Tri-state checkboxes.