(function () {
  "use strict";

  var MODE = "e2e_structures_v3";
  var RAWTEXT_MODE = "e2e_rawtext_structures";
  var STRUCTURE_MODES = [MODE, RAWTEXT_MODE];
  var ROOT = "e2e_structures_v3";
  var active = false;
  var activeMode = MODE;
  var index = null;
  var rows = [];
  var filtered = [];
  var current = 0;
  var cache = {};
  var loadSequence = 0;
  var shapeIcons = {
    tabular_records: "Table",
    chronology_and_timeline_indexes: "Timeline",
    claim_and_theme_summaries: "Claims",
    qa_shortcuts_and_templates: "QA",
    relation_graphs_and_mappings: "Graph",
  };

  function $(id) { return document.getElementById(id); }
  function esc(value) {
    return String(value === null || value === undefined ? "" : value)
      .replace(/&/g, "&amp;").replace(/</g, "&lt;")
      .replace(/>/g, "&gt;").replace(/"/g, "&quot;");
  }
  function short(value, limit) {
    value = String(value || "").replace(/\s+/g, " ").trim();
    return value.length > limit ? value.slice(0, limit - 1) + "..." : value;
  }
  function hide(id) { if ($(id)) $(id).style.display = "none"; }
  function show(id) { if ($(id)) $(id).style.display = ""; }

  function installDom() {
    if (!$("e2eStructuresControls")) {
      var controls = document.createElement("div");
      controls.id = "e2eStructuresControls";
      controls.style.display = "none";
      controls.innerHTML =
        '<div class="search-box">' +
        '<div class="sidebar-label">Constructed structures</div>' +
        '<input id="e2eStructuresSearch" type="text" placeholder="Question / qid / document...">' +
        '<select id="e2eStructuresSelect"></select></div>' +
        '<div><div class="sidebar-label">Navigate</div><div class="nav-controls">' +
        '<button id="e2eStructuresPrev" type="button">← Prev</button>' +
        '<span id="e2eStructuresCounter">0 / 0</span>' +
        '<button id="e2eStructuresNext" type="button">Next →</button>' +
        "</div></div>";
      var footer = $("sidebarFooter");
      footer.parentNode.insertBefore(controls, footer);
      $("e2eStructuresSearch").addEventListener("input", filterRows);
      $("e2eStructuresSelect").addEventListener("change", function () {
        current = parseInt(this.value, 10) || 0;
        renderCurrent();
      });
      $("e2eStructuresPrev").addEventListener("click", function () {
        if (current > 0) { current--; renderCurrent(); }
      });
      $("e2eStructuresNext").addEventListener("click", function () {
        if (current < filtered.length - 1) { current++; renderCurrent(); }
      });
    }
    if (!$("e2eStructuresView")) {
      var section = document.createElement("section");
      section.id = "e2eStructuresView";
      section.style.display = "none";
      section.innerHTML =
        '<div class="e2estruct-summary" id="e2eStructuresSummary"></div>' +
        '<div class="e2estruct-main" id="e2eStructuresMain"></div>';
      document.querySelector(".app-main").appendChild(section);
    }
  }

  function ensureButton() {
    var toggle = $("viewToggle");
    if (!toggle) return;
    var compare = toggle.querySelector('[data-mode="compare"]');
    [
      ["modeE2eStructuresV3Btn", MODE, "E2E Structures v3"],
      ["modeE2eRawtextStructuresBtn", RAWTEXT_MODE, "E2E+Rawtext Structures"],
    ].forEach(function (definition) {
      if ($(definition[0])) return;
      var button = document.createElement("button");
      button.id = definition[0];
      button.type = "button";
      button.dataset.mode = definition[1];
      button.className = definition[1] === RAWTEXT_MODE
        ? "e2e-rawtext-structures-tab"
        : "e2e-structures-tab";
      button.textContent = definition[2];
      button.addEventListener("click", activate);
      if (compare && compare.parentNode === toggle) toggle.insertBefore(button, compare);
      else toggle.appendChild(button);
    });
  }

  function deactivate() {
    var wasActive = active;
    active = false;
    window.__e2eStructuresActive = false;
    if (wasActive) window.__e2eStructuresJustClosed = true;
    hide("e2eStructuresControls");
    hide("e2eStructuresView");
    var button = $("modeE2eStructuresV3Btn");
    var rawtextButton = $("modeE2eRawtextStructuresBtn");
    if (button) button.classList.remove("active");
    if (rawtextButton) rawtextButton.classList.remove("active");
  }

  function activate(event) {
    if (event) event.stopImmediatePropagation();
    activeMode = event && event.currentTarget.dataset.mode || activeMode;
    active = true;
    if (index) renderSummary();
    window.__e2eStructuresActive = true;
    window.__e2eStructuresJustClosed = false;
    if ($("setSelect") && $("setSelect").value !== "size5000_seed1") {
      $("setSelect").value = "size5000_seed1";
      $("setSelect").dispatchEvent(new Event("change"));
    }
    if ($("setSelect")) $("setSelect").disabled = true;
    if ($("scopeNote")) $("scopeNote").style.display = "";
    document.querySelectorAll("#viewToggle button").forEach(function (button) {
      button.classList.toggle("active", button.dataset.mode === activeMode);
    });
    ["corpusControls", "evalControls", "runControls", "compareControls"].forEach(hide);
    ["corpusView", "evalView", "runView", "compareView"].forEach(hide);
    hide("loading");
    show("e2eStructuresControls");
    show("e2eStructuresView");
    loadIndex().then(function () {
      if (!active) return;
      filterRows();
    }).catch(function (error) {
      $("e2eStructuresMain").innerHTML =
        '<div class="e2estruct-empty">Failed to load structures: ' + esc(error) + "</div>";
    });
  }

  function loadIndex() {
    if (index) return Promise.resolve(index);
    $("e2eStructuresMain").innerHTML =
      '<div class="e2estruct-empty">Loading E2E v3 structure index...</div>';
    return fetch(ROOT + "/index.json").then(function (response) {
      if (!response.ok) throw new Error("index HTTP " + response.status);
      return response.json();
    }).then(function (value) {
      index = value;
      rows = value.rows || [];
      renderSummary();
      return value;
    });
  }

  function renderSummary() {
    var meta = index.meta || {};
    $("e2eStructuresSummary").innerHTML =
      '<div><b>' + esc(activeMode === RAWTEXT_MODE
        ? "E2E+Rawtext Structures"
        : (meta.label || "E2E Structures v3")) + "</b></div>" +
      (activeMode === RAWTEXT_MODE
        ? "<div>The five generated shapes were reused exactly; raw universe documents were mounted as a sixth fallback overlay.</div>"
        : "") +
      '<div class="e2estruct-pills">' +
      '<span>' + esc(meta.n_qids) + " questions</span>" +
      '<span>' + esc(meta.n_source_docs) + " supporting docs</span>" +
      '<span>' + esc(meta.n_structures_total) + " structures</span>" +
      "</div>";
  }

  function filterRows() {
    var query = $("e2eStructuresSearch").value.trim().toLowerCase();
    var selected = filtered[current] && filtered[current].qid;
    var sharedQid = window.TrajectoryUI && window.TrajectoryUI.getQid();
    filtered = rows.filter(function (row) {
      if (!query) return true;
      return [
        row.qid, row.question, (row.doc_ids || []).join(" "),
        (row.source_doc_ids || []).join(" "),
      ].join(" ").toLowerCase().indexOf(query) !== -1;
    });
    current = 0;
    if (sharedQid) {
      filtered.some(function (row, position) {
        if (row.qid !== sharedQid) return false;
        current = position;
        return true;
      });
    } else if (selected) {
      filtered.some(function (row, position) {
        if (row.qid !== selected) return false;
        current = position;
        return true;
      });
    }
    var select = $("e2eStructuresSelect");
    select.innerHTML = "";
    filtered.forEach(function (row, position) {
      var option = document.createElement("option");
      option.value = String(position);
      option.textContent = row.qid + " · " + short(row.question, 72);
      select.appendChild(option);
    });
    renderCurrent();
  }

  function decodeRecord(item) {
    if (cache[item.qid]) return Promise.resolve(cache[item.qid]);
    return fetch(ROOT + "/" + item.path).then(function (response) {
      if (!response.ok) throw new Error(item.path + ": HTTP " + response.status);
      return response.text();
    }).then(function (encoded) {
      var binary = atob(encoded.trim());
      var bytes = new Uint8Array(binary.length);
      for (var i = 0; i < binary.length; i++) bytes[i] = binary.charCodeAt(i);
      if (typeof DecompressionStream === "undefined") {
        throw new Error("This browser does not support gzip structure shards.");
      }
      var stream = new Blob([bytes]).stream().pipeThrough(new DecompressionStream("gzip"));
      return new Response(stream).text();
    }).then(function (text) {
      cache[item.qid] = JSON.parse(text);
      return cache[item.qid];
    });
  }

  function renderCurrent() {
    var host = $("e2eStructuresMain");
    if (!filtered.length) {
      $("e2eStructuresCounter").textContent = "0 / 0";
      $("e2eStructuresSelect").innerHTML = "";
      host.innerHTML = '<div class="e2estruct-empty">No questions match the filter.</div>';
      return;
    }
    var item = filtered[current];
    $("e2eStructuresCounter").textContent = (current + 1) + " / " + filtered.length;
    $("e2eStructuresSelect").value = String(current);
    host.innerHTML = '<div class="e2estruct-empty">Loading ' + esc(item.qid) + "...</div>";
    var sequence = ++loadSequence;
    decodeRecord(item).then(function (record) {
      if (!active || sequence !== loadSequence) return;
      renderRecord(record);
    }).catch(function (error) {
      host.innerHTML = '<div class="e2estruct-empty">Failed to load record: ' +
        esc(error) + "</div>";
    });
  }

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

  function renderStructure(structure) {
    var label = shapeIcons[structure.shape_id] || structure.shape_id;
    var unit = structure.unit_name ? " · " + structure.unit_name : "";
    return '<details class="e2estruct-shape">' +
      '<summary><span>' + esc(label) + "</span><code>" +
      esc(structure.shape_id) + esc(unit) + "</code></summary>" +
      (structure.unit_description
        ? '<div class="e2estruct-description">' + esc(structure.unit_description) + "</div>"
        : "") +
      '<pre>' + esc(structure.content || "(empty artifact)") + "</pre></details>";
  }

  function renderDocument(doc, position) {
    var sources = (doc.source_doc_ids || []).map(function (id) {
      return "<code>" + esc(id) + "</code>";
    }).join(" ");
    var structures = (doc.structures || []).map(renderStructure).join("");
    return '<details class="e2estruct-doc"' + (position === 0 ? " open" : "") + ">" +
      '<summary><span>' + esc(doc.doc_id) + "</span><b>" +
      esc(doc.n_structures) + " structures</b></summary>" +
      '<div class="e2estruct-source-ids"><b>Supporting source artifacts:</b> ' +
      (sources || "none") + "</div>" +
      '<details class="e2estruct-source"><summary>Supporting text</summary><pre>' +
      esc(doc.contents || "") + "</pre></details>" +
      (structures || '<div class="e2estruct-empty">No structures for this extraction unit.</div>') +
      "</details>";
  }

  function renderRecord(record) {
    if (window.TrajectoryUI) window.TrajectoryUI.setQid(record.qid);
    $("e2eStructuresMain").innerHTML =
      '<div class="e2estruct-question">' +
      '<div class="e2estruct-pills"><span>' + esc(record.qid) + "</span>" +
      '<span>' + esc(record.n_source_docs) + " source docs</span>" +
      '<span>' + esc(record.n_structures) + " structures</span></div>" +
      "<h2>" + esc(record.question) + "</h2>" +
      window.TrajectoryUI.gold(record.gold_answers, "Gold") + "</div>" +
      (record.docs || []).map(renderDocument).join("");
  }

  installDom();
  ensureButton();
  new MutationObserver(ensureButton).observe($("viewToggle"), { childList: true, subtree: true });
  document.addEventListener("click", function (event) {
    var button = event.target.closest && event.target.closest("#viewToggle button");
    if (button && STRUCTURE_MODES.indexOf(button.dataset.mode) === -1) deactivate();
  }, true);
  document.addEventListener("keydown", function (event) {
    if (!active || (event.key !== "ArrowLeft" && event.key !== "ArrowRight")) return;
    var tag = (event.target.tagName || "").toLowerCase();
    if (tag === "input" || tag === "select" || tag === "textarea") return;
    event.stopImmediatePropagation();
    (event.key === "ArrowLeft" ? $("e2eStructuresPrev") : $("e2eStructuresNext")).click();
  }, true);
})();