(function () {
  "use strict";

  var sharedQid = null;

  function esc(value) {
    return String(value === null || value === undefined ? "" : value)
      .replace(/&/g, "&amp;").replace(/</g, "&lt;")
      .replace(/>/g, "&gt;").replace(/"/g, "&quot;");
  }

  function text(value) {
    if (value === null || value === undefined) return "";
    if (typeof value === "string") return value;
    return JSON.stringify(value, null, 2);
  }

  function inputText(event) {
    var value = event && event.input;
    if (value === null || value === undefined) return "";
    if (typeof value !== "object" || Array.isArray(value)) return text(value);
    var keys = Object.keys(value);
    if (keys.length === 1 && typeof value[keys[0]] === "string") return value[keys[0]];
    return JSON.stringify(value, null, 2);
  }

  function humanBytes(length) {
    if (length < 1024) return length + " B";
    if (length < 1024 * 1024) return (length / 1024).toFixed(1) + " KB";
    return (length / (1024 * 1024)).toFixed(2) + " MB";
  }

  function toolStep(index, event, resultEvent) {
    var name = event.name || "tool";
    var input = inputText(event);
    var output = resultEvent ? text(resultEvent.content) : "";
    var collapsed = output.length > 2000;
    return '<div class="pretty-step tool tool-' + esc(name) + '">' +
      '<div class="pretty-step-head"><span class="pretty-step-index">' + index +
      '</span><span class="pretty-kind">tool</span><span class="pretty-tool-pill">' +
      esc(name) + "</span></div>" +
      (input ? '<div class="pretty-label">Input</div><pre class="pretty-input">' +
        esc(input) + "</pre>" : "") +
      (resultEvent ? '<div class="pretty-label">Output <span>' +
        humanBytes(output.length) + '</span></div><div class="pretty-output-wrap' +
        (collapsed ? " collapsed" : "") + '"><pre class="pretty-output">' +
        esc(output) + "</pre>" +
        (collapsed ? '<button type="button" class="pretty-output-toggle">Expand output ▾</button>' : "") +
        "</div>" : "") +
      "</div>";
  }

  function messageStep(index, event) {
    var content = text(event.content).trim();
    if (!content) return "";
    return '<div class="pretty-step model"><div class="pretty-step-head">' +
      '<span class="pretty-step-index">' + index +
      '</span><span class="pretty-kind">model</span></div>' +
      '<div class="pretty-model-text">' + esc(content) + "</div></div>";
  }

  function otherStep(index, event) {
    var content = text(event.content || event.input || event);
    return '<div class="pretty-step other"><div class="pretty-step-head">' +
      '<span class="pretty-step-index">' + index + '</span><span class="pretty-kind">' +
      esc(event.type || "event") + "</span></div>" +
      '<pre class="pretty-output">' + esc(content) + "</pre></div>";
  }

  function render(events, label) {
    events = events || [];
    if (!events.length) return "";
    var parts = [];
    var step = 0;
    for (var i = 0; i < events.length; i++) {
      var event = events[i] || {};
      if (event.type === "tool_call") {
        step++;
        var next = events[i + 1];
        parts.push(toolStep(step, event, next && next.type === "tool_result" ? next : null));
        if (next && next.type === "tool_result") i++;
      } else if (event.type === "tool_result") {
        step++;
        parts.push(toolStep(step, { name: "tool" }, event));
      } else if (["text", "llm_response", "assistant", "model"].indexOf(event.type) >= 0) {
        step++;
        parts.push(messageStep(step, event));
      } else if (event.type !== "done") {
        step++;
        parts.push(otherStep(step, event));
      }
    }
    return '<details class="pretty-trajectory"><summary>' +
      esc(label || "Agent trajectory") + " · " + events.length +
      ' events</summary><div class="pretty-steps">' + parts.join("") + "</div></details>";
  }

  function bind(container) {
    if (!container) return;
    container.querySelectorAll(".pretty-output-toggle").forEach(function (button) {
      button.addEventListener("click", function () {
        var wrap = button.closest(".pretty-output-wrap");
        var collapsed = wrap.classList.toggle("collapsed");
        button.textContent = collapsed ? "Expand output ▾" : "Collapse output ▴";
      });
    });
  }

  function goldItems(value) {
    var values = Array.isArray(value) ? value : [value];
    return values.filter(function (item) {
      return item !== null && item !== undefined && String(item).trim() !== "";
    }).map(function (item) {
      if (typeof item === "object") {
        return item.answer_text || item.value || item.name || JSON.stringify(item);
      }
      return String(item);
    });
  }

  function gold(value, label) {
    var values = goldItems(value);
    return '<div class="compact-gold"><span class="compact-gold-label">' +
      esc(label || "Gold") + (values.length > 1 ? " · " + values.length : "") +
      '</span><div class="compact-gold-pills">' +
      (values.length ? values.map(function (item) {
        return '<span class="compact-gold-pill" title="' + esc(item) + '">' +
          esc(item) + "</span>";
      }).join("") : '<span class="compact-gold-empty">none</span>') +
      "</div></div>";
  }

  function supporting(label, html, count) {
    return '<details class="compact-supporting"><summary>' + esc(label) +
      (count !== undefined ? " · " + count : "") +
      '</summary><div class="compact-supporting-body">' + html + "</div></details>";
  }

  window.TrajectoryUI = {
    render: render,
    bind: bind,
    gold: gold,
    supporting: supporting,
    setQid: function (qid) { if (qid !== null && qid !== undefined) sharedQid = String(qid); },
    getQid: function () { return sharedQid; },
  };
})();