(function () {
  "use strict";

  window.CO_ServerList = {
    pingClass: function (ping) {
      if (ping <= 50) return "co-ping-good";
      if (ping <= 100) return "co-ping-mid";
      return "co-ping-bad";
    },

    isLocalHost: function (host) {
      if (!host) return false;
      return /^(127\.0\.0\.1|localhost|::1)$/i.test(String(host).trim());
    },

    displayName: function (server) {
      if (!server) return "";
      var host = server.host || server.address || "";
      var port = server.port > 0 ? server.port : 7777;
      var name = String(server.name || "").trim();
      var isLocal = server.region === "Local" || CO_ServerList.isLocalHost(host);
      var isDirect = server.id === "direct" || name === "Direct Connect";
      if (!name || isLocal || isDirect) {
        return (host || "127.0.0.1") + ":" + port;
      }
      return name;
    },

    render: function (root, state) {
      var wrap = root.querySelector(".co-server-list-wrap");
      var list = root.querySelector(".co-server-list");
      if (!wrap || !list) return;

      wrap.className = "co-server-list-wrap" + (state.focusZone === "server-list" ? " focused" : "");
      var isRecent = state.activeTab === "recent";
      var isLocal = state.activeTab === "local";

      if (!state.servers.length) {
        var emptyText = "No servers found";
        if (isRecent) emptyText = "No recent servers";
        else if (isLocal) {
          emptyText = state.isScanningLocal ?
            "Scanning local network..." :
            "No local servers found. Check the host PC is running server.py and firewall allows UDP 7778 / TCP 7777.";
        }
        list.innerHTML = '<div class="co-empty">' + emptyText + "</div>";
        CO_ServerList.updateScrollIndicator(wrap, list);
        return;
      }

      list.innerHTML = state.servers.map(function (server, index) {
        var selected = index === state.selectedServerIndex ? " selected" : "";
        var label = CO_ServerList.displayName(server);

        if (isRecent) {
          return (
            '<div class="co-server-row' + selected + '" data-index="' + index + '" data-id="' + escapeAttr(server.id || "") + '">' +
            '<div class="co-server-row-left">' +
            '<span class="co-server-row-name">' + escapeHtml(label) + "</span>" +
            "</div>" +
            "</div>"
          );
        }

        if (isLocal) {
          var pingCls = CO_ServerList.pingClass(server.ping || 0);
          return (
            '<div class="co-server-row' + selected + '" data-index="' + index + '" data-id="' + escapeAttr(server.id || "") + '">' +
            '<div class="co-server-row-left">' +
            '<span class="co-server-row-name">' + escapeHtml(label) + "</span>" +
            "</div>" +
            '<div class="co-server-row-right">' +
            "<span>" + (server.players || 0) + "/" + (server.maxPlayers || 16) + "</span>" +
            '<span class="co-ping ' + pingCls + '">' + (server.ping || 0) + " ms</span>" +
            "</div>" +
            "</div>"
          );
        }

        var fav = server.favorite ? " on" : "";
        var pingCls = CO_ServerList.pingClass(server.ping);
        return (
          '<div class="co-server-row' + selected + '" data-index="' + index + '" data-id="' + escapeAttr(server.id) + '">' +
          '<div class="co-server-row-left">' +
          '<span class="co-fav' + fav + '">' + (server.favorite ? "\u2605" : "\u2606") + "</span>" +
          '<span class="co-server-row-name">' + escapeHtml(label) + "</span>" +
          "</div>" +
          '<div class="co-server-row-right">' +
          "<span>" + server.players + "/" + server.maxPlayers + "</span>" +
          '<span class="co-ping ' + pingCls + '">' + server.ping + " ms</span>" +
          "</div>" +
          "</div>"
        );
      }).join("");

      CO_ServerList.updateScrollIndicator(wrap, list);
    },

    updateScrollIndicator: function (wrap, list) {
      var indicator = wrap && wrap.querySelector(".co-scroll-indicator");
      if (!indicator || !list) return;
      var hasOverflow = list.scrollHeight > list.clientHeight + 2;
      indicator.classList.toggle("hidden", !hasOverflow);
    },

    bind: function (root, onSelect) {
      var list = root.querySelector(".co-server-list");
      if (!list) return;

      list.addEventListener("click", function (e) {
        var row = e.target.closest(".co-server-row");
        if (!row) return;
        onSelect(parseInt(row.getAttribute("data-index"), 10));
      });

      list.addEventListener("dblclick", function (e) {
        var row = e.target.closest(".co-server-row");
        if (!row) return;
        onSelect(parseInt(row.getAttribute("data-index"), 10));
        if (window.CO_App && window.CO_App.joinSelected) {
          window.CO_App.joinSelected();
        }
      });
    },

    scrollToSelected: function (root, index) {
      var list = root.querySelector(".co-server-list");
      var row = list && list.querySelector('.co-server-row[data-index="' + index + '"]');
      if (row) {
        row.scrollIntoView({ block: "nearest" });
      }
      var wrap = root.querySelector(".co-server-list-wrap");
      if (wrap && list) {
        CO_ServerList.updateScrollIndicator(wrap, list);
      }
    }
  };

  function escapeHtml(value) {
    return String(value)
      .replace(/&/g, "&amp;")
      .replace(/</g, "&lt;")
      .replace(/>/g, "&gt;");
  }

  function escapeAttr(value) {
    return String(value).replace(/"/g, "&quot;");
  }
})();