// ═══════════════════════════════════════════════════════════════════
// shared/sortable.js | v1.0.0 | 2026-05-10 | task N5
// Auto-attaches click-to-sort to every <table> with a <thead><tr><th>.
//
// Usage: <script src="/static/shared/sortable.js" defer></script>
// Skips:
//   • tables with [data-sort-skip] attribute
//   • tables already using the legacy sportHeader() pattern (those have
//     sort handlers wired in their <th> already; we detect them and bail)
//
// Click behavior per <th>:
//   1st click → ASC
//   2nd click → DESC
//   3rd click → unsorted (original order restored)
//
// Type detection per column (sampled from first 8 non-empty rows):
//   numeric → integers / floats / "1.234,56 €" / "12 kn"
//   date    → ISO yyyy-mm-dd or hr-HR dd.mm.yyyy
//   string  → fallback, locale-aware (hr-HR collation)
// ═══════════════════════════════════════════════════════════════════
(function(){
'use strict';

var ARROW_NEUTRAL = ' ↕';
var ARROW_ASC     = ' ▲';
var ARROW_DESC    = ' ▼';
var COLLATOR      = (typeof Intl !== 'undefined' && Intl.Collator)
  ? new Intl.Collator('hr-HR', { numeric: true, sensitivity: 'base' })
  : null;

function txt(node){ return (node.textContent || '').trim(); }

function detectType(samples){
  // Decide column type from up to 8 sample cell values
  var nNum = 0, nDate = 0, n = 0;
  for (var i = 0; i < samples.length && n < 8; i++){
    var v = samples[i];
    if (v === '' || v === '—' || v === '-' || v == null) continue;
    n++;
    if (parseHRNumber(v) !== null) nNum++;
    else if (parseDate(v))         nDate++;
  }
  if (n === 0) return 'string';
  if (nNum  / n >= 0.6) return 'numeric';
  if (nDate / n >= 0.6) return 'date';
  return 'string';
}

function parseHRNumber(s){
  // Accept: "1234", "1.234,56", "1,234.56", "1 234", "12 kn", "€ 12,5", "0.45"
  var raw = String(s).replace(/[^\d,.\- ]/g, '').trim();
  if (raw === '' || raw === '-') return null;
  // Detect decimal separator: if both . and , present, the rightmost is decimal
  var hasComma = raw.indexOf(',') >= 0, hasDot = raw.indexOf('.') >= 0;
  var cleaned;
  if (hasComma && hasDot){
    if (raw.lastIndexOf(',') > raw.lastIndexOf('.')){
      cleaned = raw.replace(/\./g, '').replace(/ /g, '').replace(',', '.');
    } else {
      cleaned = raw.replace(/,/g, '').replace(/ /g, '');
    }
  } else if (hasComma){
    // could be 1234,56 or 1,234 — treat , as decimal if exactly one and 1-2 digits after
    var parts = raw.split(',');
    if (parts.length === 2 && parts[1].replace(/ /g,'').length <= 2){
      cleaned = parts[0].replace(/ /g,'').replace(/\./g,'') + '.' + parts[1].replace(/ /g,'');
    } else {
      cleaned = raw.replace(/,/g, '').replace(/ /g, '');
    }
  } else {
    cleaned = raw.replace(/ /g, '');
  }
  var n = parseFloat(cleaned);
  return isFinite(n) ? n : null;
}

var DATE_ISO = /^\d{4}-\d{2}-\d{2}/;
var DATE_HR  = /^(\d{1,2})\.\s*(\d{1,2})\.\s*(\d{4})/;
function parseDate(s){
  s = String(s).trim();
  if (DATE_ISO.test(s)) return Date.parse(s.slice(0, 10));
  var m = s.match(DATE_HR);
  if (m) return Date.parse(m[3] + '-' + ('0'+m[2]).slice(-2) + '-' + ('0'+m[1]).slice(-2));
  return null;
}

function compare(type, a, b){
  if (type === 'numeric'){
    var na = parseHRNumber(a), nb = parseHRNumber(b);
    if (na === null && nb === null) return 0;
    if (na === null) return 1;
    if (nb === null) return -1;
    return na - nb;
  }
  if (type === 'date'){
    var da = parseDate(a), db = parseDate(b);
    if (da == null && db == null) return 0;
    if (da == null) return 1;
    if (db == null) return -1;
    return da - db;
  }
  return COLLATOR ? COLLATOR.compare(a, b) : a.localeCompare(b);
}

function sampleColumn(rows, colIdx){
  var out = [];
  for (var i = 0; i < rows.length; i++){
    var c = rows[i].cells && rows[i].cells[colIdx];
    if (c) out.push(txt(c));
  }
  return out;
}

function attach(table){
  if (table.__sortableAttached) return;
  if (table.hasAttribute('data-sort-skip')) return;
  // skip tables using legacy sortHeader() — they already have <th onclick=...>
  var firstTh = table.querySelector('thead th, tr th');
  if (!firstTh) return;
  var legacy = !!table.querySelector('thead th[onclick*="setSort"], thead th[onclick*="_sort"]');
  if (legacy) return;

  var thead = table.tHead || (table.querySelector('tr') && table.querySelector('tr').parentNode);
  if (!thead) return;
  var headerRow = thead.querySelector('tr') || (table.rows[0] && table.rows[0].parentNode === thead ? table.rows[0] : null);
  if (!headerRow) return;
  var ths = headerRow.cells;
  if (!ths || ths.length === 0) return;

  // Snapshot original order so 3rd-click can revert
  var tbody = table.tBodies && table.tBodies[0];
  if (!tbody) return;
  var originalRows = Array.prototype.slice.call(tbody.rows);
  if (originalRows.length < 2) return;          // nothing to sort

  // State per table
  var state = { col: -1, dir: 0 };               // 0 = unsorted, 1 = asc, -1 = desc

  for (var i = 0; i < ths.length; i++){
    (function(idx, th){
      // Don't make non-data columns sortable (action icons etc.)
      if (th.hasAttribute('data-sort-skip')) return;
      var label = txt(th);
      if (label === '') return;                  // skip empty headers (icons)
      th.style.cursor = 'pointer';
      th.style.userSelect = 'none';
      th.title = 'Klikni za sort · ASC → DESC → reset';
      // Append neutral arrow if no existing sort marker
      if (!/[↕▲▼]/.test(label)){
        var span = document.createElement('span');
        span.className = '__sort-ind';
        span.style.opacity = '0.45';
        span.textContent = ARROW_NEUTRAL;
        th.appendChild(span);
      }
      th.addEventListener('click', function(){
        // Cycle: idx is current → asc; same idx asc → desc; same idx desc → reset
        if (state.col !== idx){ state.col = idx; state.dir = 1; }
        else if (state.dir === 1){ state.dir = -1; }
        else if (state.dir === -1){ state.col = -1; state.dir = 0; }
        else { state.dir = 1; }

        // Update arrow indicators on all ths
        for (var j = 0; j < ths.length; j++){
          var ind = ths[j].querySelector('.__sort-ind');
          if (!ind) continue;
          if (j === state.col){
            ind.style.opacity = '1';
            ind.textContent = state.dir === 1 ? ARROW_ASC : ARROW_DESC;
          } else {
            ind.style.opacity = '0.45';
            ind.textContent = ARROW_NEUTRAL;
          }
        }

        if (state.dir === 0){
          // Restore original order
          for (var k = 0; k < originalRows.length; k++) tbody.appendChild(originalRows[k]);
          return;
        }

        var rows = Array.prototype.slice.call(tbody.rows);
        var samples = sampleColumn(rows, idx);
        var type = detectType(samples);
        rows.sort(function(a, b){
          var av = a.cells[idx] ? txt(a.cells[idx]) : '';
          var bv = b.cells[idx] ? txt(b.cells[idx]) : '';
          var c = compare(type, av, bv);
          return state.dir === 1 ? c : -c;
        });
        for (var r = 0; r < rows.length; r++) tbody.appendChild(rows[r]);
      });
    })(i, ths[i]);
  }
  table.__sortableAttached = true;
}

function attachAll(scope){
  var root = scope || document;
  var tables = root.querySelectorAll ? root.querySelectorAll('table') : [];
  for (var i = 0; i < tables.length; i++) attach(tables[i]);
}

// Auto-init on DOMContentLoaded; also re-scan when DOM mutates (SPAs that
// re-render tables in-place).
function boot(){
  attachAll(document);
  if (typeof MutationObserver !== 'undefined'){
    var rescan = function(){ attachAll(document); };
    var obs = new MutationObserver(function(muts){
      for (var i = 0; i < muts.length; i++){
        if (muts[i].addedNodes && muts[i].addedNodes.length){
          // throttle — debounce 100ms
          if (boot._t) clearTimeout(boot._t);
          boot._t = setTimeout(rescan, 100);
          break;
        }
      }
    });
    obs.observe(document.body, { childList: true, subtree: true });
  }
}
if (document.readyState === 'loading'){
  document.addEventListener('DOMContentLoaded', boot);
} else {
  boot();
}

// Public API for explicit re-scans from app code
window.attachSortable = attachAll;
})();