// SelectArena leaderboard: a static page over the generated files in data/.
//
// data/meta.json lists every published subset; each subset folder
// data/subsets/tasks_<t>/models_<m>/budgets_<b>/ holds elo_explorer.html and leaderboard_table.html,
// which are embedded as iframes. The folder names mirror selectarena.website.subsets.Subset.rel_path.
// Every embedded page posts {saFrameHeight: <px>} to this window; the listener below resizes its iframe.
(function () {
  'use strict';

  var ALL = 'all';
  var TASK_LABELS = {
    all: 'All tasks',
    classification: 'Classification',
    binary: 'Binary',
    multiclass: 'Multiclass',
    regression: 'Regression'
  };
  var TABS = ['leaderboard', 'datasets', 'robustness', 'about'];
  var state = { tab: 'leaderboard', tasks: ALL, model: ALL, budget: ALL };
  var meta = null;
  var published = {};

  function $(id) { return document.getElementById(id); }
  function key(s) { return s.tasks + '|' + s.model + '|' + s.budget; }
  function subsetDir(s) {
    return 'data/subsets/tasks_' + s.tasks + '/models_' + s.model + '/budgets_' + s.budget + '/';
  }
  function withAxis(axis, value) {
    var s = { tasks: state.tasks, model: state.model, budget: state.budget };
    s[axis] = value;
    return s;
  }

  // 0.5 -> "0.5", 0.75 -> "0.75", 1 -> "1.0"
  function noiseLabel(value) { return Number(value).toFixed(2).replace(/0$/, ''); }

  function budgetLabel(index, total) {
    var label = 'Budget ' + (index + 1);
    if (total && index === 0) return label + ' (smallest)';
    if (total && index === total - 1) return label + ' (largest)';
    return label;
  }

  // ---- URL hash: #tab=...&tasks=...&model=...&budget=... (shareable selections) ----
  function readHash() {
    var params = new URLSearchParams(window.location.hash.slice(1));
    ['tab', 'tasks', 'model', 'budget'].forEach(function (k) {
      var v = params.get(k);
      if (v) state[k] = v;
    });
    if (TABS.indexOf(state.tab) < 0) state.tab = 'leaderboard';
  }
  function writeHash() {
    var params = new URLSearchParams();
    if (state.tab !== 'leaderboard') params.set('tab', state.tab);
    ['tasks', 'model', 'budget'].forEach(function (k) { if (state[k] !== ALL) params.set(k, state[k]); });
    var hash = params.toString();
    try {
      history.replaceState(null, '', hash ? '#' + hash : window.location.pathname + window.location.search);
    } catch (e) { /* sandboxed frame: the selection still works, it just is not in the URL */ }
  }

  // ---- iframes ----
  function setFrame(frame, src) {
    if (frame.getAttribute('src') !== src) frame.setAttribute('src', src);
  }
  window.addEventListener('message', function (event) {
    var data = event.data;
    if (!data || typeof data.saFrameHeight !== 'number') return;
    document.querySelectorAll('iframe.sa-frame').forEach(function (frame) {
      if (frame.contentWindow === event.source) frame.style.height = data.saFrameHeight + 'px';
    });
  });

  // ---- header ----
  function renderFacts() {
    var version = document.querySelector('meta[name="selectarena-version"]').getAttribute('content');
    $('current-version').textContent = 'v' + version;
    var facts = [];
    if (meta) {
      var models = Object.keys(meta.models || {}).map(function (k) { return meta.models[k]; });
      facts.push(meta.n_methods + ' methods', meta.n_datasets + ' datasets');
      if (models.length) facts.push('downstream models: ' + models.join(', '));
      facts.push('updated ' + meta.generated_at);
    }
    facts.push('v' + version);
    var list = $('facts');
    list.textContent = '';
    facts.forEach(function (text) {
      var li = document.createElement('li');
      li.textContent = text;
      list.appendChild(li);
    });
  }

  // ---- tabs ----
  function showTab(tab) {
    state.tab = tab;
    TABS.forEach(function (t) {
      $('tab-' + t).setAttribute('aria-selected', String(t === tab));
      $('tab-' + t).tabIndex = t === tab ? 0 : -1;
      $('panel-' + t).hidden = t !== tab;
    });
    if (tab === 'datasets') loadDatasets();
    if (tab === 'robustness') loadRobustness();
    writeHash();
  }
  function initTabs() {
    document.querySelectorAll('[role="tab"]').forEach(function (button) {
      button.addEventListener('click', function () { showTab(button.dataset.tab); });
      button.addEventListener('keydown', function (event) {
        var i = TABS.indexOf(button.dataset.tab);
        if (event.key === 'ArrowRight' || event.key === 'ArrowLeft') {
          var next = TABS[(i + (event.key === 'ArrowRight' ? 1 : TABS.length - 1)) % TABS.length];
          showTab(next);
          $('tab-' + next).focus();
        }
      });
    });
  }

  // ---- leaderboard ----
  function axisOptions() {
    var taskTypes = meta.task_types || [ALL];
    var models = meta.models || {};
    return {
      tasks: Object.keys(TASK_LABELS)
        .filter(function (k) { return taskTypes.indexOf(k) >= 0; })
        .map(function (k) { return { value: k, label: TASK_LABELS[k] }; }),
      model: [{ value: ALL, label: 'All models' }].concat(
        Object.keys(models).map(function (k) { return { value: k, label: models[k] }; })),
      budget: [{ value: ALL, label: 'All budgets' }].concat(
        (meta.budgets || []).map(function (b) { return { value: String(b), label: budgetLabel(b, meta.total_budget) }; }))
    };
  }

  function renderChips(axis, options) {
    var container = $('chips-' + axis);
    container.textContent = '';
    options.forEach(function (option) {
      var button = document.createElement('button');
      button.type = 'button';
      button.className = 'chip';
      button.textContent = option.label;
      button.setAttribute('aria-pressed', String(option.value === state[axis]));
      var available = published[key(withAxis(axis, option.value))];
      if (!available && option.value !== state[axis]) {
        button.disabled = true;
        button.title = 'No leaderboard for this combination';
      }
      button.addEventListener('click', function () {
        state[axis] = option.value;
        renderLeaderboard();
        writeHash();
      });
      container.appendChild(button);
    });
  }

  function renderLeaderboard() {
    var options = axisOptions();
    ['tasks', 'model', 'budget'].forEach(function (axis) { renderChips(axis, options[axis]); });

    var info = published[key(state)];
    var scope = [
      TASK_LABELS[state.tasks] || state.tasks,
      state.model === ALL ? 'all downstream models' : (meta.models[state.model] || state.model),
      state.budget === ALL ? 'all budgets' : budgetLabel(Number(state.budget), meta.total_budget)
    ].join(' · ');
    var summary = $('summary');
    summary.textContent = '';
    var strong = document.createElement('strong');
    strong.textContent = scope;
    summary.appendChild(strong);
    if (!info) {
      $('subset-missing').hidden = false;
      $('subset-content').hidden = true;
      return;
    }
    summary.appendChild(document.createTextNode(
      ': ' + info.n_methods + ' methods on ' + info.n_datasets + ' datasets, ' +
      info.n_comparisons.toLocaleString('en-US') + ' method results compared.'));
    $('subset-missing').hidden = true;
    $('subset-content').hidden = false;
    var dir = subsetDir(state);
    setFrame($('frame-figure'), dir + 'elo_explorer.html');
    var table = $('frame-table');
    if (table.getAttribute('src') !== dir + 'leaderboard_table.html') {
      table.style.height = (info.n_methods * 37 + 90) + 'px';
    }
    setFrame(table, dir + 'leaderboard_table.html');
  }

  // ---- other tabs (loaded on first view) ----
  function loadDatasets() {
    if (!meta) { $('datasets-missing').hidden = false; $('frame-datasets').hidden = true; return; }
    setFrame($('frame-datasets'), 'data/per_dataset_table.html');
  }
  function loadRobustness() {
    var hasStability = !!(meta && meta.has_stability);
    $('stability-missing').hidden = hasStability;
    $('frame-stability').hidden = !hasStability;
    if (hasStability) setFrame($('frame-stability'), 'data/stability_table.html');

    // One validity table per noise level (meta.validity_tables); older data had a single table.
    var tables = (meta && meta.validity_tables) || [];
    if (!tables.length && meta && meta.has_validity) tables = [{ noise: null, path: 'validity_table.html' }];
    $('validity-missing').hidden = tables.length > 0;
    var container = $('validity-tables');
    if (!container.childElementCount) {
      tables.forEach(function (table) {
        if (table.noise != null) {
          var heading = document.createElement('h3');
          heading.textContent = 'Noise level ' + noiseLabel(table.noise) +
            (Number(table.noise) === Number(meta.validity_noise) ? ' (used on the leaderboard)' : '');
          container.appendChild(heading);
        }
        var frame = document.createElement('iframe');
        frame.className = 'frame sa-frame';
        frame.title = 'Validity per method' + (table.noise != null ? ' at noise level ' + noiseLabel(table.noise) : '');
        frame.style.height = '640px';
        frame.src = 'data/' + table.path;
        container.appendChild(frame);
      });
    }
    if (meta && meta.validity_noise != null) $('validity-noise').textContent = noiseLabel(meta.validity_noise);
  }

  // ---- start ----
  function start() {
    readHash();
    initTabs();
    fetch('data/meta.json', { cache: 'no-cache' })
      .then(function (response) {
        if (!response.ok) throw new Error('HTTP ' + response.status);
        return response.json();
      })
      .then(function (data) {
        meta = data;
        (meta.subsets || []).forEach(function (s) { published[key(s)] = s; });
        if (!published[key(state)]) { state.tasks = ALL; state.model = ALL; state.budget = ALL; }
        $('leaderboard-content').hidden = false;
        renderFacts();
        renderLeaderboard();
        showTab(state.tab);
      })
      .catch(function () {
        meta = null;
        $('no-results').hidden = false;
        renderFacts();
        showTab(state.tab);
      });
  }

  start();
})();