shiloh-echo/js/agenda.js

document.addEventListener("DOMContentLoaded", function () {
  var tabs = Array.prototype.slice.call(
    document.querySelectorAll('[role="tab"]')
  );
  var panels = Array.prototype.slice.call(
    document.querySelectorAll('[role="tabpanel"]')
  );

  if (tabs.length === 0) return;

  function activateTab(tab, isClick) {
    tabs.forEach(function (t) {
      var sel = t === tab;
      t.setAttribute("aria-selected", String(sel));
      var panelId = t.getAttribute("aria-controls");
      var panel = document.getElementById(panelId);
      if (panel) panel.setAttribute("aria-hidden", String(!sel));
    });
    tab.focus({ preventScroll: true });
    if (isClick) {
      var panelId = tab.getAttribute("aria-controls");
      var panel = document.getElementById(panelId);
      if (panel) {
        var rect = panel.getBoundingClientRect();
        window.scrollTo({
          top: rect.top + window.pageYOffset - 80,
          behavior: "smooth",
        });
      }
    }
  }

  tabs.forEach(function (tab, index) {
    tab.addEventListener("click", function () {
      activateTab(tab, true);
    });
    tab.addEventListener("keydown", function (e) {
      if (e.key === "ArrowRight") {
        tabs[(index + 1) % tabs.length].click();
      } else if (e.key === "ArrowLeft") {
        tabs[(index - 1 + tabs.length) % tabs.length].click();
      }
    });
  });

  var initial = document.getElementById("tab-friday") || tabs[0];
  if (initial) activateTab(initial, false);
});