/* TrainChain — lightweight front-end (no dependencies). */
(function () {
  "use strict";

  // Close mobile nav when a link is tapped or on resize.
  document.querySelectorAll(".nav a").forEach(function (a) {
    a.addEventListener("click", function () { document.body.classList.remove("nav-open"); });
  });
  window.addEventListener("resize", function () {
    if (window.innerWidth > 720) document.body.classList.remove("nav-open");
  });

  // Station autocomplete for any <input data-station>.
  document.querySelectorAll("input[data-station]").forEach(function (input) {
    var box = document.createElement("div");
    box.className = "ac-box";
    box.style.cssText =
      "position:absolute;z-index:60;background:#fff;border:1px solid var(--line);" +
      "border-radius:12px;box-shadow:var(--shadow);margin-top:4px;max-height:240px;" +
      "overflow:auto;display:none;min-width:220px;max-width:calc(100vw - 36px)";
    input.parentNode.style.position = "relative";
    input.parentNode.appendChild(box);
    var timer = null;

    input.addEventListener("input", function () {
      var q = input.value.trim();
      clearTimeout(timer);
      if (q.length < 2) { box.style.display = "none"; return; }
      timer = setTimeout(function () {
        fetch("/stations.php?q=" + encodeURIComponent(q))
          .then(function (r) { return r.json(); })
          .then(function (rows) {
            box.innerHTML = "";
            if (!rows.length) { box.style.display = "none"; return; }
            rows.forEach(function (s) {
              var item = document.createElement("button");
              item.type = "button";
              item.textContent = s.name + " (" + s.code + ")";
              item.style.cssText =
                "display:block;width:100%;text-align:left;border:0;background:none;" +
                "padding:11px 14px;cursor:pointer;font:inherit;color:var(--ink)";
              item.addEventListener("mouseenter", function () { item.style.background = "var(--brand-50)"; });
              item.addEventListener("mouseleave", function () { item.style.background = "none"; });
              item.addEventListener("click", function () {
                input.value = s.name + " (" + s.code + ")";
                input.dataset.code = s.code;
                box.style.display = "none";
              });
              box.appendChild(item);
            });
            box.style.display = "block";
          })
          .catch(function () { box.style.display = "none"; });
      }, 180);
    });

    document.addEventListener("click", function (ev) {
      if (ev.target !== input) box.style.display = "none";
    });
  });

  // Swap the From/To station fields (value + autocomplete code).
  window.rrSwap = function (btn) {
    var form = btn.closest("form"); if (!form) return;
    var a = form.querySelector('input[name="from"]'),
        b = form.querySelector('input[name="to"]');
    if (!a || !b) return;
    var v = a.value; a.value = b.value; b.value = v;
    var c = a.dataset.code || ""; a.dataset.code = b.dataset.code || ""; b.dataset.code = c;
  };

})();