/* MuDABench viewer — vanilla JS, two tabs: Corpus + Eval. */
(function () {
  "use strict";

  var $ = function (id) { return document.getElementById(id); };

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

  function fmtVal(v) {
    if (v === null || v === undefined) return '<span class="fval-null">null</span>';
    if (v === true) return '<span class="fval-bool-true">true</span>';
    if (v === false) return '<span class="fval-bool-false">false</span>';
    return esc(String(v));
  }

  function shortId(id) { return id ? String(id).slice(0, 8) : ""; }

  var state = {
    mode: "corpus",
    corpus: [],        // all docs
    corpusView: [],    // filtered docs
    corpusIdx: 0,
    byId: {},          // id -> corpus doc
    questions: [],     // all questions
    evalView: [],      // filtered questions
    evalIdx: 0,
  };

  /* ---------------- data loading ---------------- */
  function loadAll() {
    return Promise.all([
      fetch("corpus_index.json").then(function (r) { return r.json(); }),
      fetch("eval.json").then(function (r) { return r.json(); }),
    ]).then(function (res) {
      state.corpus = res[0] || [];
      state.questions = res[1] || [];
      state.corpus.forEach(function (d) { state.byId[d.id] = d; });
    });
  }

  /* ---------------- corpus tab ---------------- */
  function populateCorpusFilters() {
    var types = {}, years = {};
    state.corpus.forEach(function (d) {
      if (d.doctype) types[d.doctype] = true;
      if (d.year !== null && d.year !== undefined && d.year !== "") years[d.year] = true;
    });
    var tf = $("docTypeFilter"), yf = $("yearFilter");
    Object.keys(types).sort().forEach(function (t) {
      var o = document.createElement("option"); o.value = t; o.textContent = t; tf.appendChild(o);
    });
    Object.keys(years).sort().forEach(function (y) {
      var o = document.createElement("option"); o.value = y; o.textContent = y; yf.appendChild(o);
    });
  }

  function filterCorpus() {
    var q = $("corpusFilter").value.trim().toLowerCase();
    var typ = $("docTypeFilter").value;
    var yr = $("yearFilter").value;
    state.corpusView = state.corpus.filter(function (d) {
      if (typ && d.doctype !== typ) return false;
      if (yr && String(d.year) !== yr) return false;
      if (q) {
        var hay = (d.title + " " + (d.symbol || "") + " " + (d.id || "")).toLowerCase();
        if (hay.indexOf(q) === -1) return false;
      }
      return true;
    });
    if (state.corpusIdx >= state.corpusView.length) state.corpusIdx = 0;
    rebuildDocSelect();
    renderCorpus();
  }

  function rebuildDocSelect() {
    var sel = $("docSelect");
    sel.innerHTML = "";
    state.corpusView.forEach(function (d, i) {
      var o = document.createElement("option");
      o.value = String(i);
      o.textContent = d.title + "  ·  " + shortId(d.id);
      sel.appendChild(o);
    });
    sel.value = String(state.corpusIdx);
  }

  function renderCorpus() {
    var meta = $("docMetaCard");
    var frame = $("pdfFrame");
    if (!state.corpusView.length) {
      meta.innerHTML = '<div class="empty">No documents match the filter.</div>';
      frame.removeAttribute("src");
      $("corpusCounter").textContent = "0 / 0";
      return;
    }
    var d = state.corpusView[state.corpusIdx];
    $("docSelect").value = String(state.corpusIdx);
    $("corpusCounter").textContent = (state.corpusIdx + 1) + " / " + state.corpusView.length;

    var pills = [];
    if (d.symbol) pills.push('<span class="meta-pill">Symbol: <b>' + esc(d.symbol) + "</b></span>");
    if (d.year !== null && d.year !== undefined && d.year !== "") pills.push('<span class="meta-pill">Year: <b>' + esc(d.year) + "</b></span>");
    if (d.doctype) pills.push('<span class="meta-pill">Type: <b>' + esc(d.doctype) + "</b></span>");
    pills.push('<span class="meta-pill">Cited by <b>' + (d.n_refs || 0) + "</b> question(s)</span>");
    pills.push('<span class="meta-pill mono">' + esc(d.id) + "</span>");
    var link = '<a class="doc-link" href="' + esc(d.pdf) + '" target="_blank" rel="noopener">open PDF ↗</a>';

    var fieldsHtml = "";
    if (d.fields && d.fields.length) {
      var rows = d.fields.map(function (f) {
        var vals = (f.values || []).map(fmtVal).join(", ");
        return "<tr><td class=\"fname\">" + esc(f.name) + "</td>" +
               "<td class=\"fval\">" + (vals || "") + "</td>" +
               "<td class=\"fdesc\">" + esc(f.desc || "") + "</td></tr>";
      }).join("");
      fieldsHtml =
        '<table class="fields-table"><thead><tr>' +
        "<th>Field</th><th>Value(s)</th><th>Description</th>" +
        "</tr></thead><tbody>" + rows + "</tbody></table>";
    }

    var refsHtml = "";
    if (d.referenced_by && d.referenced_by.length) {
      var refPills = d.referenced_by.map(function (r) {
        return '<span class="ref-pill" data-qid="' + esc(r.qid) + '" data-ds="' + esc(r.dataset) +
               '">' + esc(shortId(r.qid)) + ' <span class="ds">' + esc(r.dataset) + "</span></span>";
      }).join("");
      refsHtml =
        '<details class="refs-wrap"><summary>Referenced by ' + d.referenced_by.length +
        " question(s)</summary><div class=\"ref-pills\">" + refPills + "</div></details>";
    }

    meta.innerHTML =
      "<h2>" + esc(d.title) + "</h2>" +
      '<div class="meta-grid">' + pills.join("") + link + "</div>" +
      fieldsHtml + refsHtml;

    // wire ref pills -> jump to that question in the Eval tab
    Array.prototype.forEach.call(meta.querySelectorAll(".ref-pill"), function (el) {
      el.addEventListener("click", function () {
        setMode("eval");
        selectQuestion(this.getAttribute("data-ds"), this.getAttribute("data-qid"));
      });
    });

    frame.src = d.pdf;
  }

  function selectDocById(id) {
    // reset corpus filters so the target doc is guaranteed visible
    $("corpusFilter").value = "";
    $("docTypeFilter").value = "";
    $("yearFilter").value = "";
    state.corpusView = state.corpus.slice();
    var idx = 0;
    for (var i = 0; i < state.corpusView.length; i++) {
      if (state.corpusView[i].id === id) { idx = i; break; }
    }
    state.corpusIdx = idx;
    rebuildDocSelect();
    renderCorpus();
  }

  /* ---------------- eval tab ---------------- */
  function filterEval() {
    var q = $("evalSearch").value.trim().toLowerCase();
    var ds = $("datasetFilter").value;
    state.evalView = state.questions.filter(function (x) {
      if (ds && x.dataset !== ds) return false;
      if (q) {
        var docTitles = (x.docs || []).map(function (d) { return d.title + " " + (d.symbol || ""); }).join(" ");
        var hay = [x.question, x.final_answer, x.qid, docTitles].join(" ").toLowerCase();
        if (hay.indexOf(q) === -1) return false;
      }
      return true;
    });
    if (state.evalIdx >= state.evalView.length) state.evalIdx = 0;
    rebuildQSelect();
    renderEval();
  }

  function rebuildQSelect() {
    var sel = $("qSelect");
    sel.innerHTML = "";
    state.evalView.forEach(function (x, i) {
      var o = document.createElement("option");
      o.value = String(i);
      var q = (x.question || "").replace(/\s+/g, " ");
      if (q.length > 70) q = q.slice(0, 70) + "…";
      o.textContent = "[" + x.dataset + "] " + q;
      sel.appendChild(o);
    });
    sel.value = String(state.evalIdx);
  }

  function field(lbl, valHtml) {
    return '<div class="field"><div class="lbl">' + esc(lbl) + '</div><div class="val">' + valHtml + "</div></div>";
  }

  function renderEval() {
    var card = $("evalCard");
    if (!state.evalView.length) {
      card.innerHTML = '<div class="empty">No questions match the search.</div>';
      $("evalCounter").textContent = "0 / 0";
      return;
    }
    var x = state.evalView[state.evalIdx];
    $("qSelect").value = String(state.evalIdx);
    $("evalCounter").textContent = (state.evalIdx + 1) + " / " + state.evalView.length;

    var badges =
      '<span class="badge id">' + esc(x.qid) + "</span>" +
      '<span class="badge ds-' + esc(x.dataset) + '">' + esc(x.dataset) + "</span>";

    // supporting facts (source_answer)
    var facts = x.source_answer || [];
    var factsHtml = facts.length
      ? '<ol class="facts-list">' + facts.map(function (f) { return "<li>" + esc(f) + "</li>"; }).join("") + "</ol>"
      : '<span style="color:var(--muted)">none</span>';

    // supporting documents
    var docs = x.docs || [];
    var docsHtml = docs.map(function (d) {
      var fields = (d.fields || []).map(function (f) {
        return '<div class="doc-field"><span class="fn">' + esc(f.name) + '</span>' +
               '<span class="fv">' + fmtVal(f.value) + "</span>" +
               (f.desc ? '<span class="fd">' + esc(f.desc) + "</span>" : "") + "</div>";
      }).join("");
      return '<div class="doc-item">' +
        '<div class="doc-item-head">' +
          '<a class="doclink" data-doc-id="' + esc(d.id) + '">' + esc(d.title) + " ↗</a>" +
          '<span class="doc-id">' + esc(d.id) + "</span>" +
        "</div>" +
        (fields ? '<div class="doc-fields">' + fields + "</div>" : "") +
      "</div>";
    }).join("");

    card.innerHTML =
      '<div class="badges">' + badges + "</div>" +
      "<h2>" + esc(x.question) + "</h2>" +
      '<div class="answer-banner"><div class="lbl">Final answer (gold)</div><div class="val">' +
        esc(x.final_answer) + "</div></div>" +
      field("Supporting facts (source_answer)", factsHtml) +
      field("Supporting documents (" + docs.length + ")", docsHtml ||
        '<span style="color:var(--muted)">none</span>');

    // wire doc links -> jump to Corpus tab
    Array.prototype.forEach.call(card.querySelectorAll("a.doclink[data-doc-id]"), function (el) {
      el.addEventListener("click", function () {
        setMode("corpus");
        selectDocById(this.getAttribute("data-doc-id"));
      });
    });
  }

  function selectQuestion(dataset, qid) {
    $("evalSearch").value = "";
    $("datasetFilter").value = "";
    state.evalView = state.questions.slice();
    var idx = 0;
    for (var i = 0; i < state.evalView.length; i++) {
      if (state.evalView[i].qid === qid && state.evalView[i].dataset === dataset) { idx = i; break; }
    }
    state.evalIdx = idx;
    rebuildQSelect();
    renderEval();
  }

  /* ---------------- mode switching ---------------- */
  function setMode(mode) {
    state.mode = mode;
    $("modeCorpusBtn").classList.toggle("active", mode === "corpus");
    $("modeEvalBtn").classList.toggle("active", mode === "eval");
    $("corpusControls").style.display = mode === "corpus" ? "" : "none";
    $("evalControls").style.display = mode === "eval" ? "" : "none";
    $("corpusView").style.display = mode === "corpus" ? "flex" : "none";
    $("evalView").style.display = mode === "eval" ? "block" : "none";
  }

  /* ---------------- wiring ---------------- */
  function wire() {
    $("modeCorpusBtn").addEventListener("click", function () { setMode("corpus"); });
    $("modeEvalBtn").addEventListener("click", function () { setMode("eval"); });

    // corpus
    $("corpusFilter").addEventListener("input", filterCorpus);
    $("docTypeFilter").addEventListener("change", filterCorpus);
    $("yearFilter").addEventListener("change", filterCorpus);
    $("docSelect").addEventListener("change", function () {
      state.corpusIdx = parseInt(this.value, 10) || 0;
      renderCorpus();
    });
    $("corpusPrevBtn").addEventListener("click", function () {
      if (state.corpusIdx > 0) { state.corpusIdx--; renderCorpus(); }
    });
    $("corpusNextBtn").addEventListener("click", function () {
      if (state.corpusIdx < state.corpusView.length - 1) { state.corpusIdx++; renderCorpus(); }
    });

    // eval
    $("evalSearchBtn").addEventListener("click", filterEval);
    $("evalSearch").addEventListener("keydown", function (e) { if (e.key === "Enter") filterEval(); });
    $("evalClearBtn").addEventListener("click", function () {
      $("evalSearch").value = ""; $("datasetFilter").value = ""; filterEval();
    });
    $("datasetFilter").addEventListener("change", filterEval);
    $("qSelect").addEventListener("change", function () {
      state.evalIdx = parseInt(this.value, 10) || 0;
      renderEval();
    });
    $("evalPrevBtn").addEventListener("click", function () {
      if (state.evalIdx > 0) { state.evalIdx--; renderEval(); }
    });
    $("evalNextBtn").addEventListener("click", function () {
      if (state.evalIdx < state.evalView.length - 1) { state.evalIdx++; renderEval(); }
    });

    // keyboard arrows
    document.addEventListener("keydown", function (e) {
      var tag = (e.target.tagName || "").toLowerCase();
      if (tag === "input" || tag === "select" || tag === "textarea") return;
      if (e.key === "ArrowLeft") {
        if (state.mode === "corpus") $("corpusPrevBtn").click();
        else $("evalPrevBtn").click();
      } else if (e.key === "ArrowRight") {
        if (state.mode === "corpus") $("corpusNextBtn").click();
        else $("evalNextBtn").click();
      }
    });
  }

  /* ---------------- boot ---------------- */
  loadAll().then(function () {
    $("loading").style.display = "none";
    $("sidebarFooter").innerHTML =
      state.corpus.length + " documents · " + state.questions.length + " questions<br>" +
      '<a href="https://github.com/Zhanli-Li/MuDABench" target="_blank" rel="noopener">GitHub</a> · ' +
      '<a href="https://huggingface.co/datasets/Zhanli-Li/MuDABench" target="_blank" rel="noopener">HF dataset</a> · ' +
      '<a href="https://arxiv.org/abs/2604.22239" target="_blank" rel="noopener">arXiv</a>';
    populateCorpusFilters();
    wire();
    setMode("corpus");
    filterCorpus();
    filterEval();
  }).catch(function (err) {
    $("loading").textContent = "Failed to load data: " + err;
  });
})();