/**
 * Logs page — registers the dashboard with the background to receive live log events,
 * renders a filterable/searchable log list with level filtering and auto-scroll toggle.
 * Depends on: core/utils.js ($, escapeHtml), ui/toast.js (showToast)
 */

let _logsSetup = false;

/**
 * Set up the Logs page: register for live log broadcasts, wire up filter/search/scroll controls.
 * Guarded by `_logsSetup` to prevent duplicate registration.
 */
function setupLogsEvents() {
  if (_logsSetup) return;
  _logsSetup = true;

  let logs = [];
  let autoScroll = true;
  let logFilter = '';
  let logLevel = 'all'; // 'all' | 'info' | 'warn' | 'error'

  chrome.runtime.sendMessage(
    { target: 'holesail-native', action: 'registerDashboard' },
    (response) => {
      if (response && response.logs) { logs = response.logs; updateLogsDisplay(); }
    }
  );

  function _onLogsMessage(message) {
    if (message.type === 'holesail-logs' && message.logs) {
      logs = message.logs;
      updateLogsDisplay();
    }
  }
  chrome.runtime.onMessage.addListener(_onLogsMessage);

  function getLogClass(level) {
    if (level === 'error') return 'is-error';
    if (level === 'warn') return 'is-warn';
    return '';
  }

  function updateLogsDisplay() {
    const container = $('logsContainer');
    if (!container) return;
    let filtered = logs;
    if (logFilter) {
      filtered = filtered.filter(e => (e.message || '').toLowerCase().includes(logFilter.toLowerCase()));
    }
    if (logLevel !== 'all') {
      filtered = filtered.filter(e => (e.level || 'info') === logLevel);
    }
    if (filtered.length === 0) {
      container.innerHTML = `
        <div class="empty-state">
          <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5"><polyline points="22,12 18,12 15,21 9,3 6,12 2,12"/></svg>
          <div class="empty-state-title">${(logFilter || logLevel !== 'all') ? 'No matching logs' : 'No logs yet'}</div>
          <div class="empty-state-desc">${(logFilter || logLevel !== 'all') ? 'Try a different filter' : 'Logs will appear here as the extension runs'}</div>
        </div>`;
      return;
    }
    container.innerHTML = filtered.map(entry => {
      const time = new Date(entry.timestamp).toLocaleTimeString();
      const cls = getLogClass(entry.level || 'info');
      return `<div class="log-entry">
        <span class="log-time">${time}</span>
        <span class="log-msg ${cls}">${escapeHtml(entry.message)}</span>
      </div>`;
    }).join('');
    if (autoScroll) container.scrollTop = container.scrollHeight;
  }

  $('btnClearLogs')?.addEventListener('click', () => { logs = []; updateLogsDisplay(); });

  $('btnAutoScroll')?.addEventListener('click', () => {
    autoScroll = !autoScroll;
    const btn = $('btnAutoScroll');
    if (btn) {
      const svgPart = btn.querySelector('svg')?.outerHTML || '';
      btn.innerHTML = svgPart + ' Auto-scroll: ' + (autoScroll ? 'ON' : 'OFF');
    }
  });

  $('logsFilter')?.addEventListener('input', (e) => {
    logFilter = e.target.value;
    updateLogsDisplay();
  });

  // Severity filter buttons
  document.querySelectorAll('.log-level-btn').forEach(btn => {
    btn.addEventListener('click', () => {
      document.querySelectorAll('.log-level-btn').forEach(b => b.classList.remove('active'));
      btn.classList.add('active');
      logLevel = btn.dataset.level;
      updateLogsDisplay();
    });
  });

  // Download logs as .txt
  $('btnDownloadLogs')?.addEventListener('click', () => {
    if (!logs.length) { showToast('No logs to download', 'default'); return; }
    const lines = logs.map(e => {
      const time = new Date(e.timestamp).toISOString();
      return `[${time}] ${e.message}`;
    }).join('\n');
    const blob = new Blob([lines], { type: 'text/plain' });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = 'holesail-logs-' + new Date().toISOString().slice(0, 19).replace(/:/g, '-') + '.txt';
    a.click();
    setTimeout(() => URL.revokeObjectURL(url), 5000);
    showToast('Logs downloaded', 'success');
  });

  window.addEventListener('beforeunload', () => {
    chrome.runtime.onMessage.removeListener(_onLogsMessage);
    chrome.runtime.sendMessage({ target: 'holesail-native', action: 'unregisterDashboard' }, () => {});
  }, { once: true });
}