// localtime.js - Converts UTC <time> elements to the user's local timezone.
//
// Usage: <time datetime="2026-01-14T10:30:00Z" data-localtime="datetime">fallback</time>
//
// Supported data-localtime values:
//   "date"      → "Mon 2 Jan 2026"
//   "time"      → "3:04 PM"
//   "datetime"  → "Mon 2 Jan 2026 at 3:04 PM"
//   "short"     → "Mon 2 Jan 3:04 PM"
//   "histdate"  → "2 Jan 2006 15:04"

(function () {
  const SHORT_DAYS = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'];
  const SHORT_MONTHS = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
    'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];

  function pad(n) { return n < 10 ? '0' + n : '' + n; }

  function formatTime12(d) {
    let h = d.getHours();
    const m = pad(d.getMinutes());
    const ampm = h >= 12 ? 'PM' : 'AM';
    h = h % 12 || 12;
    return h + ':' + m + ' ' + ampm;
  }

  function formatDate(d) {
    return SHORT_DAYS[d.getDay()] + ' ' + d.getDate() + ' ' +
      SHORT_MONTHS[d.getMonth()] + ' ' + d.getFullYear();
  }

  function formatLocalTime(el) {
    const iso = el.getAttribute('datetime');
    if (!iso) return;
    const d = new Date(iso);
    if (isNaN(d.getTime())) return;

    const fmt = el.getAttribute('data-localtime');
    let text;
    switch (fmt) {
      case 'date':
        text = formatDate(d);
        break;
      case 'time':
        text = formatTime12(d);
        break;
      case 'datetime':
        text = formatDate(d) + ' at ' + formatTime12(d);
        break;
      case 'short':
        text = SHORT_DAYS[d.getDay()] + ' ' + d.getDate() + ' ' +
          SHORT_MONTHS[d.getMonth()] + ' ' + formatTime12(d);
        break;
      case 'histdate':
        text = d.getDate() + ' ' + SHORT_MONTHS[d.getMonth()] + ' ' +
          d.getFullYear() + ' ' + pad(d.getHours()) + ':' + pad(d.getMinutes());
        break;
      default:
        text = formatDate(d) + ' at ' + formatTime12(d);
    }
    el.textContent = text;

    // Add timezone tooltip so users know the displayed time is in their local timezone
    var tz = Intl.DateTimeFormat().resolvedOptions().timeZone;
    el.title = 'Displayed in your local timezone (' + tz + ')';
  }

  function processAll(root) {
    const els = (root || document).querySelectorAll('time[data-localtime]');
    els.forEach(formatLocalTime);
  }

  // Process on page load
  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', function () { processAll(); });
  } else {
    processAll();
  }

  // Re-process after HTMX swaps
  document.addEventListener('htmx:afterSettle', function (evt) {
    processAll(evt.detail.elt);
  });
})();