var Search = (function() {
  var dropdownVisible = false;
  var selectedIndex = -1;
  var results = [];
  var debounceTimer = null;
  var currentInput = null;

  // Page title mapping
  var PAGE_TITLES = {
    'index.html': 'Home',
    'terminology.html': 'Terminology',
    'techniques.html': 'Techniques',
    'use-cases.html': 'Use Cases',
    'model-types.html': 'Model Types',
    'prompts.html': 'Prompt Guide',
    'math.html': 'Math & Concepts',
    'chat.html': 'Chat',
    'image-gen.html': 'Image Gen'
  };

  // Content to skip during crawling
  var SKIP_CONTENT = [
    'AI Cheat Sheet',
    'Toggle dark mode',
    'Toggle menu',
    'Send',
    'Ask me anything about AI',
    'Ask a Question',
    'Ask anything about AI',
    'Powered by your configured LLM',
    'Try AI right now',
    'Full Chat',
    'Generate',
    'Clear',
    'Image Generation',
    'Enter image prompt'
  ];

  function init() {
    var navInner = document.querySelector('.nav-inner');
    if (!navInner) return;

    var brand = navInner.querySelector('.nav-brand');
    if (!brand) return;

    // Create search wrapper
    var searchWrapper = document.createElement('div');
    searchWrapper.className = 'sidebar-search';
    searchWrapper.style.cssText = 'position:relative; margin-top:0.5rem; margin-bottom:0.25rem;';

    var searchInput = document.createElement('input');
    searchInput.type = 'text';
    searchInput.className = 'sidebar-search-input';
    searchInput.placeholder = 'Search...';
    searchInput.setAttribute('aria-label', 'Search all pages');
    searchInput.autocomplete = 'off';

    searchWrapper.appendChild(searchInput);

    // Insert after brand
    brand.parentNode.insertBefore(searchWrapper, brand.nextSibling);

    // Move results container inside search wrapper for correct absolute positioning
    var existingContainer = document.getElementById('searchResultsContainer');
    if (existingContainer) {
      searchWrapper.appendChild(existingContainer);
    }

    currentInput = searchInput;

    // Event listeners
    searchInput.addEventListener('input', function(e) {
      clearTimeout(debounceTimer);
      var query = e.target.value.trim();
      if (query.length === 0) {
        hideDropdown();
        return;
      }
      debounceTimer = setTimeout(function() {
        performSearch(query);
      }, 150);
    });

    searchInput.addEventListener('keydown', function(e) {
      if (!dropdownVisible || results.length === 0) return;

      if (e.key === 'ArrowDown') {
        e.preventDefault();
        selectedIndex = Math.min(selectedIndex + 1, results.length - 1);
        updateSelection();
      } else if (e.key === 'ArrowUp') {
        e.preventDefault();
        selectedIndex = Math.max(selectedIndex - 1, 0);
        updateSelection();
      } else if (e.key === 'Enter') {
        e.preventDefault();
        if (selectedIndex >= 0 && selectedIndex < results.length) {
          navigateToResult(results[selectedIndex]);
        } else if (results.length > 0) {
          navigateToResult(results[0]);
        }
      } else if (e.key === 'Escape') {
        e.preventDefault();
        hideDropdown();
        searchInput.blur();
      }
    });

    searchInput.addEventListener('focus', function() {
      if (results.length > 0 && currentInput.value.trim().length > 0) {
        showDropdown();
      }
    });

    // Close dropdown when clicking outside
    document.addEventListener('click', function(e) {
      if (!searchWrapper.contains(e.target)) {
        hideDropdown();
      }
    });
  }

  function crawlPage(url, callback) {
    fetch(url)
      .then(function(response) { return response.text(); })
      .then(function(html) {
        var parser = new DOMParser();
        var doc = parser.parseFromString(html, 'text/html');
        var results = [];

        // Get page title
        var pageTitle = PAGE_TITLES[doc.title.replace(' - Cheat Sheet', '').replace('AI Cheat Sheet', '').trim()] || doc.title;

        // Extract def-cards
        var defCards = doc.querySelectorAll('.def-card');
        defCards.forEach(function(card) {
          var heading = card.querySelector('h3');
          var p = card.querySelector('p');
          var example = card.querySelector('.example');
          var category = card.querySelector('.category');

          if (!heading || !p) return;

          var headingText = heading.textContent.trim();
          var defText = p.textContent.trim();
          var catText = category ? category.textContent.trim() : '';
          var exText = example ? example.textContent.trim() : '';

          var fullText = (catText + ' ' + headingText + ' ' + defText + ' ' + exText).trim();
          if (fullText.length < 10) return;

          // Skip boilerplate content
          var skip = false;
          for (var i = 0; i < SKIP_CONTENT.length; i++) {
            if (fullText.indexOf(SKIP_CONTENT[i]) === 0) { skip = true; break; }
          }
          if (skip) return;

          results.push({
            page: pageTitle,
            url: url,
            heading: headingText,
            category: catText,
            snippet: defText,
            fullText: fullText.toLowerCase()
          });
        });

        // Extract table rows
        var tables = doc.querySelectorAll('.glossary-table tbody tr');
        tables.forEach(function(row) {
          var tds = row.querySelectorAll('td');
          if (tds.length < 2) return;

          var acronym = tds[0].textContent.trim();
          var meaning = tds[1].textContent.trim();

          results.push({
            page: pageTitle,
            url: url,
            heading: acronym,
            category: 'Acronym',
            snippet: meaning,
            fullText: (acronym + ' ' + meaning).toLowerCase()
          });
        });

        // Extract section headings for pages without def-cards (like use-cases, model-types)
        var sections = doc.querySelectorAll('h2.section-title');
        sections.forEach(function(h2) {
          var sectionName = h2.textContent.trim();
          // Check if there are cards under this section
          var next = h2.nextElementSibling;
          var cards = [];
          while (next && !next.classList.contains('section-title')) {
            if (next.classList && (next.classList.contains('card') || next.classList.contains('use-card') || next.classList.contains('prompt-block') || next.classList.contains('def-card'))) {
              cards.push(next);
            }
            next = next.nextElementSibling;
          }

          cards.forEach(function(card) {
            var h3 = card.querySelector('h3');
            var p = card.querySelector('p');
            if (!h3 || !p) return;

            var headingText = h3.textContent.trim();
            var cardText = p.textContent.trim();

            // Skip if already captured as def-card
            if (card.classList.contains('def-card')) return;

            results.push({
              page: pageTitle,
              url: url,
              heading: headingText,
              category: sectionName,
              snippet: cardText,
              fullText: (sectionName + ' ' + headingText + ' ' + cardText).toLowerCase()
            });
          });
        });

        // For pages with .use-grid, extract use-cards
        var useGrid = doc.querySelector('.use-grid');
        if (useGrid) {
          var useCards = useGrid.querySelectorAll('.use-card');
          useCards.forEach(function(card) {
            var h3 = card.querySelector('h3');
            var p = card.querySelector('p');
            if (!h3 || !p) return;
            var headingText = h3.textContent.trim();
            var cardText = p.textContent.trim();

            results.push({
              page: pageTitle,
              url: url,
              heading: headingText,
              category: 'Use Case',
              snippet: cardText,
              fullText: (headingText + ' ' + cardText).toLowerCase()
            });
          });
        }

        // For prompt guide, extract prompt-blocks
        var promptBlocks = doc.querySelectorAll('.prompt-block');
        if (promptBlocks.length > 0) {
          promptBlocks.forEach(function(block) {
            var h3 = block.querySelector('h3');
            var label = block.querySelector('.label');
            var p = block.querySelector('p');

            if (!h3) return;
            var headingText = h3.textContent.trim();
            var labelText = label ? label.textContent.trim() : '';
            var cardText = p ? p.textContent.trim() : '';

            results.push({
              page: pageTitle,
              url: url,
              heading: headingText,
              category: labelText || 'Prompt',
              snippet: cardText,
              fullText: (headingText + ' ' + labelText + ' ' + cardText).toLowerCase()
            });
          });
        }

        // For math page, extract def-cards (already handled above)
        // For model-types, also grab comparison table
        var modelTables = doc.querySelectorAll('.glossary-table');
        if (modelTables.length > 0) {
          modelTables.forEach(function(table) {
            var rows = table.querySelectorAll('tbody tr');
            rows.forEach(function(row) {
              var tds = row.querySelectorAll('td');
              if (tds.length === 0) return;
              var rowText = '';
              for (var i = 0; i < tds.length; i++) {
                rowText += ' ' + tds[i].textContent.trim();
              }
              if (rowText.length < 5) return;

              results.push({
                page: pageTitle,
                url: url,
                heading: tds[0] ? tds[0].textContent.trim() : 'Table Entry',
                category: 'Comparison',
                snippet: rowText.trim(),
                fullText: rowText.toLowerCase()
              });
            });
          });
        }

        callback(results);
      })
      .catch(function() {
        callback([]);
      });
  }

  function crawlAllPages(callback) {
    var pages = [
      { url: '/index.html', title: 'Home' },
      { url: '/pages/terminology.html', title: 'Terminology' },
      { url: '/pages/techniques.html', title: 'Techniques' },
      { url: '/pages/use-cases.html', title: 'Use Cases' },
      { url: '/pages/model-types.html', title: 'Model Types' },
      { url: '/pages/prompts.html', title: 'Prompt Guide' },
      { url: '/pages/math.html', title: 'Math & Concepts' }
    ];

    var allResults = [];
    var completed = 0;

    if (pages.length === 0) {
      callback(allResults);
      return;
    }

    pages.forEach(function(page) {
      crawlPage(page.url, function(results) {
        allResults = allResults.concat(results);
        completed++;
        if (completed === pages.length) {
          callback(allResults);
        }
      });
    });
  }

  function performSearch(query) {
    var q = query.toLowerCase().trim();
    if (q.length === 0) { hideDropdown(); return; }

    crawlAllPages(function(allResults) {
      searchResults(allResults, q);
    });
  }

  function searchResults(allResults, q) {
    var qWords = q.split(/\s+/).filter(function(w) { return w.length > 0; });
    var scored = [];

    for (var i = 0; i < allResults.length; i++) {
      var item = allResults[i];
      var text = item.fullText || '';
      var score = 0;

      if (text.indexOf(q) !== -1) score += 100;

      for (var j = 0; j < qWords.length; j++) {
        if (text.indexOf(qWords[j]) !== -1) score += 10;
        if (item.heading && item.heading.toLowerCase().indexOf(qWords[j]) === 0) score += 20;
        if (item.category && item.category.toLowerCase().indexOf(qWords[j]) !== -1) score += 5;
      }

      if (score > 0) {
        scored.push({ item: item, score: score });
      }
    }

    scored.sort(function(a, b) { return b.score - a.score; });
    var topResults = scored.slice(0, 10).map(function(s) { return s.item; });
    displayResults(topResults, q);
  }

  function highlightText(text, query) {
    if (!text || !query) return escapeHTML(text);
    var escaped = escapeHTML(text);
    var qWords = query.toLowerCase().split(/\s+/).filter(function(w) { return w.length > 0; });

    for (var i = 0; i < qWords.length; i++) {
      var word = qWords[i];
      var regex = new RegExp('(' + escapeRegex(word) + ')', 'gi');
      escaped = escaped.replace(regex, '<mark class="search-highlight">$1</mark>');
    }

    return escaped;
  }

  function escapeRegex(str) {
    return str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
  }

  function escapeHTML(str) {
    var div = document.createElement('div');
    div.textContent = str;
    return div.innerHTML;
  }

  function displayResults(foundResults, query) {
    results = foundResults;
    selectedIndex = -1;

    if (results.length === 0) {
      showDropdown();
      var container = document.getElementById('searchResultsContainer');
      if (container) {
        container.innerHTML = '<div class="search-no-results">No results found for "' + escapeHTML(query) + '"</div>';
      }
      return;
    }

    var container = document.getElementById('searchResultsContainer');
    var html = '';
    for (var i = 0; i < results.length; i++) {
      var r = results[i];
      var categoryLabel = r.category ? '<span class="search-result-category">' + escapeHTML(r.category) + '</span>' : '';
      var highlightedSnippet = highlightText(r.snippet, query);

      html += '<div class="search-result-item" data-index="' + i + '" data-url="' + escapeHTML(r.url) + '">';
      html += '<div class="search-result-title">';
      html += '<span class="search-result-page">' + escapeHTML(r.page) + '</span>';
      html += categoryLabel;
      html += '</div>';
      html += '<div class="search-result-heading">' + highlightText(r.heading, query) + '</div>';
      html += '<div class="search-result-snippet">' + highlightedSnippet + '</div>';
      html += '</div>';
    }
    container.innerHTML = html;
    showDropdown();

    // Attach click handlers
    var items = container.querySelectorAll('.search-result-item');
    for (var j = 0; j < items.length; j++) {
      items[j].addEventListener('click', function() {
        var url = this.getAttribute('data-url');
        navigateToResult({ url: url });
      });
      items[j].addEventListener('mouseenter', function() {
        var idx = parseInt(this.getAttribute('data-index'), 10);
        selectedIndex = idx;
        updateSelection();
      });
    }
  }

  function updateSelection() {
    var items = document.querySelectorAll('.search-result-item');
    for (var i = 0; i < items.length; i++) {
      if (i === selectedIndex) {
        items[i].classList.add('active');
        items[i].scrollIntoView({ block: 'nearest' });
      } else {
        items[i].classList.remove('active');
      }
    }
  }

  function showDropdown() {
    var container = document.getElementById('searchResultsContainer');
    if (container) {
      container.style.display = 'block';
      dropdownVisible = true;
    }
  }

  function hideDropdown() {
    var container = document.getElementById('searchResultsContainer');
    if (container) {
      container.style.display = 'none';
    }
    dropdownVisible = false;
    selectedIndex = -1;
  }

  function navigateToResult(result) {
    hideDropdown();
    if (currentInput) currentInput.blur();
    window.location.href = result.url;
  }

  return {
    init: init
  };
})();