'use strict';

/**
 * Entry point for the Exit Metrics Visualization Dashboard.
 * This module initializes the UI, fetches metric data, and attaches events.
 */

import { fetchMetrics } from './api.js';
import { renderDashboard, updateDashboardFilters } from './ui.js';

/**
 * Registers event listeners for user interactions.
 * @returns {void}
 */
function attachEventListeners() {
  const filterPinned = document.querySelector('#filter-pinned');
  const filterUnpinned = document.querySelector('#filter-unpinned');
  const setupSelector = document.querySelector('#setup-fingerprint');

  // Defensive checks for elements
  if (filterPinned) {
    filterPinned.addEventListener('click', async () => {
      await refreshMetrics({ filter: 'pinned' });
    });
  }

  if (filterUnpinned) {
    filterUnpinned.addEventListener('click', async () => {
      await refreshMetrics({ filter: 'unpinned' });
    });
  }

  if (setupSelector) {
    setupSelector.addEventListener('change', async (e) => {
      const setupId = e.target.value.trim();
      await refreshMetrics({ setup_fingerprint: setupId || undefined });
    });
  }

  window.addEventListener('resize', () => {
    renderDashboard(window.__metricsData || []);
  });
}

/**
 * Fetches metrics and updates the dashboard.
 * @param {object} [params] Optional query params for filtering.
 */
async function refreshMetrics(params = {}) {
  try {
    const data = await fetchMetrics(params);
    if (Array.isArray(data)) {
      window.__metricsData = data;
      renderDashboard(data);
      updateDashboardFilters(params);
    } else {
      console.warn('Unexpected API response format:', data);
    }
  } catch (error) {
    console.error('Failed to refresh metrics:', error);
  }
}

/**
 * Initializes the app after DOMContentLoaded.
 * Fetches initial metrics and sets up UI interactions.
 */
async function initApp() {
  try {
    await refreshMetrics();
    attachEventListeners();
  } catch (error) {
    console.error('Initialization failed:', error);
  }
}

window.addEventListener('load', initApp);

export { initApp, attachEventListeners };