MenuItem.prototype.handleKeydown = function()

in src/studies/apg/menu/menubar/js/PopupMenuItemLinks.js [59:162]
84 lines of code
19 McCabe index (conditional complexity)

MenuItem.prototype.handleKeydown = function (event) {
  var tgt  = event.currentTarget,
    char = event.key,
    flag = false,
    clickEvent;

  function isPrintableCharacter (str) {
    return str.length === 1 && str.match(/\S/);
  }

  switch (event.keyCode) {
    case this.keyCode.SPACE:
    case this.keyCode.RETURN:
      if (this.popupMenu) {
        this.popupMenu.open();
        this.popupMenu.setFocusToFirstItem();
      }
      else {

        // Create simulated mouse event to mimic the behavior of ATs
        // and let the event handler handleClick do the housekeeping.
        try {
          clickEvent = new MouseEvent('click', {
            'view': window,
            'bubbles': true,
            'cancelable': true
          });
        }
        catch (err) {
          if (document.createEvent) {
            // DOM Level 3 for IE 9+
            clickEvent = document.createEvent('MouseEvents');
            clickEvent.initEvent('click', true, true);
          }
        }
        tgt.dispatchEvent(clickEvent);
      }

      flag = true;
      break;

    case this.keyCode.UP:
      this.menu.setFocusToPreviousItem(this);
      flag = true;
      break;

    case this.keyCode.DOWN:
      this.menu.setFocusToNextItem(this);
      flag = true;
      break;

    case this.keyCode.LEFT:
      this.menu.setFocusToController('previous', true);
      this.menu.close(true);
      flag = true;
      break;

    case this.keyCode.RIGHT:
      if (this.popupMenu) {
        this.popupMenu.open();
        this.popupMenu.setFocusToFirstItem();
      }
      else {
        this.menu.setFocusToController('next', true);
        this.menu.close(true);
      }
      flag = true;
      break;

    case this.keyCode.HOME:
    case this.keyCode.PAGEUP:
      this.menu.setFocusToFirstItem();
      flag = true;
      break;

    case this.keyCode.END:
    case this.keyCode.PAGEDOWN:
      this.menu.setFocusToLastItem();
      flag = true;
      break;

    case this.keyCode.ESC:
      this.menu.setFocusToController();
      this.menu.close(true);
      flag = true;
      break;

    case this.keyCode.TAB:
      this.menu.setFocusToController();
      break;

    default:
      if (isPrintableCharacter(char)) {
        this.menu.setFocusByFirstCharacter(this, char);
        flag = true;
      }
      break;
  }

  if (flag) {
    event.stopPropagation();
    event.preventDefault();
  }
};