const pickerFrame = document.querySelector('#selector-picker');
const loadPicker = document.querySelector('#load-picker');
const pickerStatus = document.querySelector('#picker-status');
const pickerSelection = document.querySelector('#picker-selection');
const pickedSelector = document.querySelector('#picked-selector');
const pickedText = document.querySelector('#picked-text');
const pickedCount = document.querySelector('#picked-count');
const pickedContainer = document.querySelector('#picked-container');
const pickedRelative = document.querySelector('#picked-relative');
const applySelector = document.querySelector('#apply-selector');
const resetPicker = document.querySelector('#reset-picker');
const pickerSteps = document.querySelector('#picker-steps');
const pickerWorkspace = document.querySelector('#picker-workspace');
const pickerContainerCount = document.querySelector('#picker-container-count');
const pickerWarning = document.querySelector('#picker-warning');
const pickerPreviewEmpty = document.querySelector('#picker-preview-empty');
const pickerPreviewRows = document.querySelector('#picker-preview-rows');
const guidedTargets = ['item_selector', 'title_selector', 'date_selector', 'time_selector'];
const targetLabels = { item_selector: 'event container', title_selector: 'title', date_selector: 'date or range', time_selector: 'time' };
let currentSelection = null;
let pickerStep = 0;
let containerSelector = '';
let fieldSelectors = {};

function currentTarget() { return guidedTargets[Math.min(pickerStep, guidedTargets.length - 1)]; }
function renderPickerSteps() {
  pickerSteps?.querySelectorAll('li').forEach((step, index) => {
    step.classList.toggle('active', index === pickerStep);
    step.classList.toggle('complete', index < pickerStep);
  });
}
function sendPickerConfig() {
  pickerFrame?.contentWindow?.postMessage({ type: 'what2do-picker-config', containerSelector, fieldSelectors }, location.origin);
}
function resetPickerState() {
  currentSelection = null; pickerStep = 0; containerSelector = ''; fieldSelectors = {};
  pickerSelection.hidden = true; pickerWarning.hidden = true; pickerPreviewRows.replaceChildren(); pickerPreviewEmpty.hidden = false;
  pickerContainerCount.textContent = ''; pickerStatus.textContent = 'Step 1: click one complete event container.';
  renderPickerSteps(); sendPickerConfig();
}

if (loadPicker && pickerFrame) loadPicker.addEventListener('click', async () => {
  const url = document.querySelector('input[name="url"]')?.value.trim();
  if (!url) { pickerStatus.textContent = 'Enter a page URL first.'; return; }
  loadPicker.disabled = true; pickerStatus.textContent = 'Downloading and sanitizing page…';
  try {
    const body = new FormData(); body.append('url', url);
    const response = await fetch('/picker/snapshots', { method: 'POST', body });
    const result = await response.json();
    if (!response.ok) throw new Error(result.error || 'Unable to create preview');
    pickerFrame.src = result.preview_url; pickerWorkspace.hidden = false; pickerSteps.hidden = false; resetPicker.hidden = false;
    resetPickerState();
  } catch (error) { pickerStatus.textContent = error.message; }
  finally { loadPicker.disabled = false; }
});
if (resetPicker) resetPicker.addEventListener('click', resetPickerState);
if (pickerFrame) pickerFrame.addEventListener('load', sendPickerConfig);

window.addEventListener('message', event => {
  if (!pickerFrame || event.source !== pickerFrame.contentWindow) return;
  if (event.data?.type === 'what2do-selector') {
    if (pickerStep >= guidedTargets.length) return;
    currentSelection = event.data;
    const target = currentTarget();
    pickedSelector.textContent = target === 'item_selector' ? (event.data.containerSelector || event.data.generalizedSelector) : event.data.relativeSelector;
    pickedCount.textContent = target === 'item_selector' ? `${event.data.containerCount || event.data.generalizedCount} matching containers` : 'Corresponding field selector';
    pickedContainer.textContent = target === 'item_selector' ? (event.data.containerSelector || event.data.generalizedSelector) : containerSelector;
    pickedRelative.textContent = target === 'item_selector' ? 'All matches will be highlighted.' : event.data.relativeSelector;
    pickedText.textContent = event.data.text || event.data.tag;
    applySelector.disabled = target !== 'item_selector' && !event.data.withinConfiguredContainer;
    applySelector.textContent = `Use as ${targetLabels[target]}`;
    pickerSelection.hidden = false;
    pickerStatus.textContent = applySelector.disabled ? 'Pick a field inside one of the highlighted event containers.' : `Review this ${targetLabels[target]}, then confirm.`;
  }
  if (event.data?.type === 'what2do-picker-preview') renderExtractionPreview(event.data);
});

function updateSelectorField(target, selector) {
  const input = document.querySelector(`[name="${target}"]`);
  if (input) input.value = selector;
  try {
    const strategy = JSON.parse(strategyJson.value || '{}');
    if ((strategy.mode || 'html') === 'html') {
      strategy[target] = selector;
      strategyJson.value = JSON.stringify(strategy, null, 2);
    }
  } catch (_) {}
}

function renderExtractionPreview(data) {
  pickerContainerCount.textContent = data.containerCount ? `${data.containerCount} containers` : '';
  pickerPreviewRows.replaceChildren();
  data.rows.forEach(row => {
    const item = document.createElement('div');
    item.className = 'picker-preview-row';
    const title = document.createElement('strong'); title.textContent = row.title_selector || `Container ${row.index}`; item.append(title);
    const details = [row.date_selector, row.time_selector].filter(Boolean).join(' · ');
    if (details) { const meta = document.createElement('span'); meta.textContent = details; item.append(meta); }
    pickerPreviewRows.append(item);
  });
  pickerPreviewEmpty.hidden = data.rows.length > 0;
  if (data.inconsistencies.length) {
    pickerWarning.textContent = data.inconsistencies.map(issue => `${targetLabels[issue.target] || issue.target}: exactly one match in ${issue.present}/${issue.total} containers${issue.multiple ? `; multiple matches in ${issue.multiple}` : ''}`).join(' ');
    pickerWarning.hidden = false;
  } else pickerWarning.hidden = true;
}

if (applySelector) applySelector.addEventListener('click', () => {
  if (!currentSelection) return;
  const target = currentTarget();
  if (target === 'item_selector') {
    containerSelector = currentSelection.containerSelector || currentSelection.generalizedSelector;
    if (!containerSelector) return;
    updateSelectorField(target, containerSelector);
  } else {
    if (!currentSelection.withinConfiguredContainer) return;
    fieldSelectors[target] = currentSelection.relativeSelector;
    updateSelectorField(target, currentSelection.relativeSelector);
  }
  pickerStep += 1; currentSelection = null; pickerSelection.hidden = true; sendPickerConfig(); renderPickerSteps();
  if (pickerStep < guidedTargets.length) pickerStatus.textContent = `Step ${pickerStep + 1}: pick the ${targetLabels[currentTarget()]} inside a highlighted container.`;
  else pickerStatus.textContent = 'Guided setup complete. Review the preview and any consistency warnings.';
});

const strategyTemplates = {
  html: { mode: 'html', request_url: 'https://example.org/events', method: 'GET', item_selector: '.event-card', title_selector: '.title', date_selector: '.date', time_selector: '.time', link_selector: 'a', link_attribute: 'href', description_selector: '.description', location_selector: '.venue', date_format: '' },
  json: { mode: 'json', request_url: 'https://example.org/api/events', method: 'GET', items_path: 'results', title_path: 'title', date_path: 'startDate', end_path: 'endDate', description_path: 'description', location_path: 'location.address', link_path: 'url', disabled_path: 'disabled' },
  json_join: { mode: 'json', request_url: 'https://example.org/api/sessions', method: 'GET', items_path: '', date_path: 'startDate', link_path: 'url', join_item_key: 'itemId', join_title_path: 'name', join_description_path: 'description', join_duration_path: 'duration', join: { request_url: 'https://example.org/api/items', method: 'GET', items_path: '', key_path: 'id' } },
  html_fragment: { mode: 'html_fragment', request_url: 'https://example.org/ajax', method: 'POST', body: { action: 'events' }, html_path: 'html', item_selector: '.event-card', title_selector: '.title', date_selector: '.date', link_selector: 'a', link_attribute: 'href', page_parameter: 'page', page_start: 1, max_pages: 10, total_pages_path: 'pages_total' }
};
const strategyTemplate = document.querySelector('#strategy-template');
const strategyJson = document.querySelector('#strategy-json');
if (strategyTemplate && strategyJson) strategyTemplate.addEventListener('change', () => {
  const template = strategyTemplates[strategyTemplate.value];
  if (template) strategyJson.value = JSON.stringify(template, null, 2);
});

const addressInput = document.querySelector('#venue-address');
const addressOptions = document.querySelector('#address-options');
const latitudeInput = document.querySelector('#venue-latitude');
const longitudeInput = document.querySelector('#venue-longitude');
let addressTimer;

if (addressInput && addressOptions) {
  addressInput.addEventListener('input', () => {
    clearTimeout(addressTimer);
    latitudeInput.value = '';
    longitudeInput.value = '';
    const query = addressInput.value.trim();
    if (query.length < 3) { addressOptions.hidden = true; return; }
    addressTimer = setTimeout(async () => {
      try {
        const response = await fetch(`/api/addresses?q=${encodeURIComponent(query)}`);
        const addresses = await response.json();
        addressOptions.replaceChildren();
        addresses.forEach(address => {
          const button = document.createElement('button');
          button.type = 'button';
          button.textContent = address.label;
          button.addEventListener('click', () => {
            addressInput.value = address.label;
            latitudeInput.value = address.latitude;
            longitudeInput.value = address.longitude;
            addressOptions.hidden = true;
          });
          addressOptions.append(button);
        });
        addressOptions.hidden = addresses.length === 0;
      } catch (_) { addressOptions.hidden = true; }
    }, 300);
  });
  document.addEventListener('click', event => {
    if (!event.target.closest('.address-field')) addressOptions.hidden = true;
  });
}