/**
 * javascript/logs.js
 *
 * Logs panel: container selector sidebar + log pane, backed by
 * ajax/containers.php?action=logs. "Follow" polls on an interval rather
 * than opening a persistent stream — see javascript/terminal.js for the
 * same underlying constraint (PHP-FPM's request lifecycle) applied to a
 * different panel.
 */
(function () {
  'use strict';
  const P = window.Podman;
  let containers = [];
  let selectedId = null;
  let follow = true;
  let pollHandle = null;

  function levelClass(line) {
    if (/\berror\b/i.test(line)) return 'lvl-error';
    if (/\bwarn(ing)?\b/i.test(line)) return 'lvl-warn';
    return '';
  }

  function renderLog(text) {
    const pane = P.el('log-pane');
    const atBottom = pane.scrollTop + pane.clientHeight >= pane.scrollHeight - 20;
    const lines = text.split('\n').filter(function (l) { return l.length > 0; });
    pane.innerHTML = lines.map(function (line) {
      const cls = levelClass(line);
      return '<div class="l' + (cls ? ' ' + cls : '') + '">' + P.escapeHtml(line) + '</div>';
    }).join('') || '<div class="l podman-row-sub">(no output)</div>';
    if (atBottom) pane.scrollTop = pane.scrollHeight;
  }

  function loadLogs() {
    if (!selectedId) return Promise.resolve();
    return P.get('containers', 'logs', { id: selectedId, tail: 300 }).then(function (data) {
      renderLog(data.text);
    }).catch(function (err) {
      P.el('log-pane').innerHTML = '<div class="l podman-error">' + P.escapeHtml(err.message) + '</div>';
    });
  }

  function renderSidebar() {
    const side = P.el('logs-sidebar');
    side.innerHTML = containers.map(function (c) {
      return '<div class="item' + (c.id === selectedId ? ' active' : '') + '" data-id="' + P.escapeHtml(c.id) + '">' +
        '<span class="podman-chip ' + P.stateChipClass(c.state) + '" style="padding:2px 6px;"><span class="d"></span></span> ' +
        P.escapeHtml(c.name) + '</div>';
    }).join('');
  }

  function selectContainer(id) {
    selectedId = id;
    renderSidebar();
    loadLogs();
  }

  function setPolling(enabled) {
    follow = enabled;
    if (pollHandle) clearInterval(pollHandle);
    if (follow) {
      pollHandle = setInterval(loadLogs, 4000);
    }
  }

  function init() {
    P.el('logs-sidebar').addEventListener('click', function (e) {
      const item = e.target.closest('.item[data-id]');
      if (item) selectContainer(item.dataset.id);
    });

    document.querySelectorAll('#logs-follow-toggle button').forEach(function (btn) {
      btn.addEventListener('click', function () {
        document.querySelectorAll('#logs-follow-toggle button').forEach(function (b) { b.classList.remove('active'); });
        btn.classList.add('active');
        setPolling(btn.dataset.follow === 'true');
      });
    });

    P.el('logs-filter').addEventListener('input', function (e) {
      const term = e.target.value.toLowerCase();
      P.el('log-pane').querySelectorAll('.l').forEach(function (line) {
        line.style.display = term === '' || line.textContent.toLowerCase().includes(term) ? '' : 'none';
      });
    });

    return P.get('containers', 'list').then(function (data) {
      containers = data;
      if (containers.length > 0) {
        selectedId = containers[0].id;
      }
      renderSidebar();
      setPolling(true);
      return loadLogs();
    }).catch(function (err) {
      P.el('logs-sidebar').innerHTML = '<div class="podman-error" style="padding:14px;">' + P.escapeHtml(err.message) + '</div>';
    });
  }

  P.registerPanel('logs', { init: init, refresh: loadLogs });
})();