(function (root, factory) {
  if (typeof module === 'object' && module.exports) module.exports = factory;
  else root.createMobileTaskDock = factory;
})(typeof self !== 'undefined' ? self : this, function createMobileTaskDock(options) {
  const nav = options.nav;
  const buttons = options.buttons;
  const overlays = options.overlays || [];
  let launcher = null;
  let wasHidden = false;
  let workMode = 'work';

  function select(name) {
    Object.entries(buttons).forEach(([key, button]) => {
      if (key === name) button.setAttribute('aria-current', 'page');
      else button.removeAttribute('aria-current');
    });
  }

  function refreshVisibility() {
    const hidden = overlays.some(overlay => overlay.classList.contains('open'));
    nav.hidden = hidden;
    if (wasHidden && !hidden && launcher) launcher.focus();
    wasHidden = hidden;
  }

  function start() {
    Object.entries(buttons).forEach(([name, button]) => {
      button.addEventListener('click', event => {
        launcher = event.currentTarget;
        select(name);
        options.actions[name]();
      });
    });
    options.observe(refreshVisibility, overlays);
    refreshVisibility();
  }

  function updateWork(mode, count) {
    const labels = {
      continue: ['Continue', 'Continue Today'],
      resume: ['Resume', 'Resume Today'],
      start: ['Start', 'Start Today'],
      work: ['Work', 'Work'],
    };
    workMode = labels[mode] ? mode : 'work';
    const total = Math.max(0, Number(count) || 0);
    const badge = options.attentionBadge;
    if (options.workLabel) options.workLabel.textContent = labels[workMode][0];
    if (badge) {
      badge.textContent = String(total);
      badge.hidden = total === 0;
    }
    if (buttons.work) {
      buttons.work.setAttribute(
        'aria-label',
        labels[workMode][1] + (total ? ', ' + total + ' items need attention' : '')
      );
    }
  }

  function updateAttention(count) {
    updateWork(workMode, count);
  }

  return {start, refreshVisibility, updateAttention, updateWork};
});