center fix for the edit Modal

Web/app.py

@@ -5207,55 +5207,87 @@ def upload_item():
             flash(error_msg, 'error')
             return redirect(url_for(success_redirect_endpoint))
 
-    # Check if base code is unique for single-item uploads
-    if code_4 and item_count == 1 and not it.is_code_unique(code_4[0]):
-        existing_item = it._get_items_collection().find_one({"code_4": code_4[0]})
-        if existing_item:
-            error_msg = 'Der Code wird bereits verwendet. Umleitung zum Eintrag.'
-            if is_mobile:
-                return jsonify({
-                    'success': False, 
-                    'message': error_msg,
-                    'existing_item_id': str(existing_item['_id']),
-                    'redirect_to_item': True
-                }), 400
-            
-            flash(error_msg, 'info')
-            return redirect(url_for(success_redirect_endpoint, open_item=str(existing_item['_id'])))
+    # -------------------------------------------------------------------
+    # 1. PARSE AND UNIFY CODES
+    # -------------------------------------------------------------------
+    # Assuming `code_4` might come in as a single string or a list depending on your form setup
+    primary_code_raw = request.form.get('code_4', '').strip()
+    individual_codes_raw = request.form.get('individual_codes', '').strip()
+    
+    all_item_codes = []
+    
+    if primary_code_raw:
+        all_item_codes.append(primary_code_raw)
+        
+    if individual_codes_raw:
+        # Split textarea by newlines, clean whitespace, and ignore empty lines
+        extra_codes = [c.strip() for c in individual_codes_raw.replace('\r', '').split('\n') if c.strip()]
+        
+        # Add to master list, ensuring no duplicates within the submitted list itself
+        for c in extra_codes:
+            if c not in all_item_codes:
+                all_item_codes.append(c)
+
+    # -------------------------------------------------------------------
+    # 2. OVERRIDE ITEM COUNT
+    # -------------------------------------------------------------------
+    # If the user scanned/generated codes, the amount of codes IS the item count.
+    # Otherwise, fallback to a manual item_count field if it exists.
+    if len(all_item_codes) > 0:
+        item_count = len(all_item_codes)
+    else:
+        try:
+            item_count = int(request.form.get('item_count', 1))
+        except ValueError:
+            item_count = 1
+
+    # -------------------------------------------------------------------
+    # 3. IMAGE VALIDATION
+    # -------------------------------------------------------------------
+    if upload_mode != 'library' and not is_duplicating and not images and not duplicate_images and not book_cover_image:
+        error_msg = 'Bitte laden Sie mindestens ein Bild hoch'
+        if is_mobile:
+            return jsonify({'success': False, 'message': error_msg}), 400
         else:
-            error_msg = 'Der Code wird bereits verwendet. Bitte wählen Sie einen anderen Code.'
+            flash(error_msg, 'error')
+            return redirect(url_for(success_redirect_endpoint))
+
+    # -------------------------------------------------------------------
+    # 4. UNIFIED DB UNIQUENESS VALIDATION
+    # -------------------------------------------------------------------
+    # Validate every code in our master list against the database
+    for code in all_item_codes:
+        if not it.is_code_unique(code):
+            
+            # Special case: If they only uploaded ONE item, redirect them to that existing item
+            if item_count == 1:
+                existing_item = it._get_items_collection().find_one({"code_4": code})
+                if existing_item:
+                    error_msg = 'Der Code wird bereits verwendet. Umleitung zum Eintrag.'
+                    if is_mobile:
+                        return jsonify({
+                            'success': False, 
+                            'message': error_msg,
+                            'existing_item_id': str(existing_item['_id']),
+                            'redirect_to_item': True
+                        }), 400
+                    
+                    flash(error_msg, 'info')
+                    return redirect(url_for(success_redirect_endpoint, open_item=str(existing_item['_id'])))
+            
+            # If multiple items are being uploaded, just throw a standard error
+            error_msg = f'Der Code "{code}" wird bereits von einem anderen Artikel verwendet. Bitte überprüfen Sie Ihre Eingaben.'
             if is_mobile:
                 return jsonify({'success': False, 'message': error_msg}), 400
             else:
                 flash(error_msg, 'error')
                 return redirect(url_for(success_redirect_endpoint))
 
-    # Validate optional per-item codes
-    if individual_codes:
-        if len(individual_codes) > item_count:
-            error_msg = f'Zu viele Einzelcodes angegeben ({len(individual_codes)}), erlaubt sind maximal {item_count}.'
-            if is_mobile:
-                return jsonify({'success': False, 'message': error_msg}), 400
-            flash(error_msg, 'error')
-            return redirect(url_for(success_redirect_endpoint))
-
-        if len(set(individual_codes)) != len(individual_codes):
-            error_msg = 'Doppelte Einzelcodes erkannt. Bitte alle Codes eindeutig eintragen.'
-            if is_mobile:
-                return jsonify({'success': False, 'message': error_msg}), 400
-            flash(error_msg, 'error')
-            return redirect(url_for(success_redirect_endpoint))
-
-        for specific_code in individual_codes:
-            if not it.is_code_unique(specific_code):
-                error_msg = f'Der Einzelcode "{specific_code}" wird bereits verwendet.'
-                if is_mobile:
-                    return jsonify({'success': False, 'message': error_msg}), 400
-                flash(error_msg, 'error')
-                return redirect(url_for(success_redirect_endpoint))
-
+    # -------------------------------------------------------------------
+    # 5. BATCH CODE GENERATOR (Remains mostly unchanged)
+    # -------------------------------------------------------------------
     def generate_unique_batch_code(base_code, position):
-        """Generate a unique code for every item in a batch."""
+        """Generate a unique code for every item in a batch if no specific code is provided."""
         if not base_code:
             return None
 
@@ -9376,17 +9408,137 @@ def search_word(word):
     except Exception as e:
         return jsonify({"success": False, "response": str(e)})
 
+def _fetch_from_google_books(clean_isbn):
+    """Source 1: Google Books API (Free, No Key required for basic use)"""
+    try:
+        url = f"https://www.googleapis.com/books/v1/volumes?q=isbn:{clean_isbn}"
+        response = requests.get(url, timeout=5)
+        if response.status_code != 200:
+            return None
+        
+        data = response.json()
+        if data.get('totalItems', 0) > 0 and data.get('items'):
+            book_info = data['items'][0].get('volumeInfo', {})
+            sale_info = data['items'][0].get('saleInfo', {})
+
+            price = None
+            retail_price = sale_info.get('retailPrice', {})
+            list_price = sale_info.get('listPrice', {})
+            if retail_price and 'amount' in retail_price:
+                price = f"{retail_price['amount']} {retail_price.get('currencyCode', '€')}"
+            elif list_price and 'amount' in list_price:
+                price = f"{list_price['amount']} {list_price.get('currencyCode', '€')}"
+
+            thumbnail = book_info.get('imageLinks', {}).get('thumbnail', '')
+            if thumbnail:
+                thumbnail = thumbnail.replace('http:', 'https:')
+
+            return {
+                "title": book_info.get('title', 'Unknown Title'),
+                "authors": ', '.join(book_info.get('authors', ['Unknown Author'])),
+                "publisher": book_info.get('publisher', 'Unknown Publisher'),
+                "publishedDate": book_info.get('publishedDate', 'Unknown Date'),
+                "description": book_info.get('description', 'Keine Beschreibung verfügbar'),
+                "pageCount": book_info.get('pageCount', 'Unknown'),
+                "price": price,
+                "thumbnail": thumbnail,
+                "source": "google-books"
+            }
+    except Exception as e:
+        print(f"Google Books error: {e}")
+    return None
+
+
+def _fetch_from_lobid_germany(clean_isbn):
+    """
+    Source 2: Lobid.org (hbz Network)
+    The ultimate free, keyless fallback for German Schoolbooks and DACH literature.
+    """
+    try:
+        url = f"https://lobid.org/resources?q=isbn:{clean_isbn}&format=json"
+        response = requests.get(url, timeout=5)
+        if response.status_code != 200:
+            return None
+            
+        data = response.json()
+        if 'member' in data and len(data['member']) > 0:
+            book = data['member'][0]
+            
+            # Extract Authors (Lobid uses a nested contribution array)
+            authors = []
+            for contrib in book.get('contribution', []):
+                if 'agent' in contrib and 'label' in contrib['agent']:
+                    authors.append(contrib['agent']['label'])
+            
+            # Extract Publishers
+            publishers = []
+            for pub in book.get('publication', []):
+                if 'publishedBy' in pub:
+                    # sometimes publishedBy is a list, sometimes a string
+                    pub_data = pub['publishedBy']
+                    if isinstance(pub_data, list):
+                        publishers.extend(pub_data)
+                    else:
+                        publishers.append(pub_data)
+            
+            # Extract Date
+            pub_date = 'Unknown Date'
+            if book.get('publication'):
+                pub_date = book['publication'][0].get('startDate', 'Unknown Date')
+                
+            # Extract Pages
+            pages = book.get('extent', ['Unknown'])[0] if 'extent' in book else 'Unknown'
+            
+            return {
+                "title": book.get('title', 'Unknown Title'),
+                "authors": ', '.join(authors) if authors else 'Unknown Author',
+                "publisher": ', '.join(publishers) if publishers else 'Unknown Publisher',
+                "publishedDate": str(pub_date),
+                "description": 'Keine Beschreibung verfügbar (Schulbuch / Fachliteratur)',
+                "pageCount": pages,
+                "price": None,
+                "thumbnail": "", # Lobid rarely has covers, we will fallback to OpenLibrary cover below
+                "source": "lobid-germany"
+            }
+    except Exception as e:
+        print(f"Lobid error: {e}")
+    return None
+
+
+def _fetch_from_open_library(clean_isbn):
+    """Source 3: Open Library Search API (Free, No Key required)"""
+    try:
+        url = f"https://openlibrary.org/search.json?isbn={clean_isbn}"
+        response = requests.get(url, timeout=5)
+        if response.status_code != 200:
+            return None
+            
+        data = response.json()
+        if data.get('numFound', 0) > 0 and data.get('docs'):
+            book_info = data['docs'][0]
+            
+            return {
+                "title": book_info.get('title', 'Unknown Title'),
+                "authors": ', '.join(book_info.get('author_name', ['Unknown Author'])),
+                "publisher": ', '.join(book_info.get('publisher', ['Unknown Publisher'])),
+                "publishedDate": str(book_info.get('publish_date', ['Unknown Date'])[0]),
+                "description": 'Keine Beschreibung verfügbar',
+                "pageCount": book_info.get('number_of_pages_median', 'Unknown'),
+                "price": None,
+                "thumbnail": f"https://covers.openlibrary.org/b/isbn/{clean_isbn}-L.jpg",
+                "source": "openlibrary"
+            }
+    except Exception as e:
+        print(f"OpenLibrary Search error: {e}")
+    return None
+
 @app.route('/fetch_book_info/<isbn>')
 def fetch_book_info(isbn):
     """
-    API endpoint to fetch book information by ISBN using Google Books API
-    
-    Args:
-        isbn (str): ISBN to look up
-        
-    Returns:
-        dict: Book information or error message
+    API endpoint to fetch book information by ISBN using multiple open sources.
+    Optimized for global literature AND German educational books.
     """
+    # Authorization Checks
     if 'username' not in session or not us.check_admin(session['username']):
         return jsonify({"error": "Not authorized"}), 403
 
@@ -9394,79 +9546,33 @@ def fetch_book_info(isbn):
         return jsonify({"error": "Bibliotheks-Modul ist deaktiviert."}), 403
 
     try:
+        # Validation
         clean_isbn = normalize_and_validate_isbn(isbn)
         if not clean_isbn:
             return jsonify({"error": "Ungültige ISBN. Bitte ISBN-10 oder ISBN-13 verwenden."}), 400
 
-        # First source: Google Books
-        response = requests.get(
-            f"https://www.googleapis.com/books/v1/volumes?q=isbn:{clean_isbn}",
-            timeout=10
-        )
+        # Define the Provider Chain (Order matters: General -> German/School -> Global Fallback)
+        providers = [
+            _fetch_from_google_books,
+            _fetch_from_lobid_germany,
+            _fetch_from_open_library
+        ]
 
-        if response.status_code == 200:
-            data = response.json()
-            if data.get('totalItems', 0) > 0 and data.get('items'):
-                book_info = data['items'][0].get('volumeInfo', {})
-                sale_info = data['items'][0].get('saleInfo', {})
-
-                price = None
-                retail_price = sale_info.get('retailPrice', {})
-                list_price = sale_info.get('listPrice', {})
-                if retail_price and 'amount' in retail_price:
-                    price = f"{retail_price['amount']} {retail_price.get('currencyCode', '€')}"
-                elif list_price and 'amount' in list_price:
-                    price = f"{list_price['amount']} {list_price.get('currencyCode', '€')}"
-
-                thumbnail = book_info.get('imageLinks', {}).get('thumbnail', '')
-                if thumbnail:
-                    thumbnail = thumbnail.replace('http:', 'https:')
-
-                return jsonify({
-                    "title": book_info.get('title', 'Unknown Title'),
-                    "authors": ', '.join(book_info.get('authors', ['Unknown Author'])),
-                    "publisher": book_info.get('publisher', 'Unknown Publisher'),
-                    "publishedDate": book_info.get('publishedDate', 'Unknown Date'),
-                    "description": book_info.get('description', 'No description available'),
-                    "pageCount": book_info.get('pageCount', 'Unknown'),
-                    "price": price,
-                    "thumbnail": thumbnail,
-                    "isbn": clean_isbn,
-                    "source": "google-books"
-                })
-
-        # Fallback: OpenLibrary
-        ol_response = requests.get(
-            f"https://openlibrary.org/isbn/{clean_isbn}.json",
-            timeout=10
-        )
-        if ol_response.status_code == 200:
-            ol_data = ol_response.json()
-            author_names = []
-            for author_ref in ol_data.get('authors', []):
-                key = author_ref.get('key')
-                if not key:
-                    continue
-                try:
-                    author_resp = requests.get(f"https://openlibrary.org{key}.json", timeout=8)
-                    if author_resp.status_code == 200:
-                        author_names.append(author_resp.json().get('name'))
-                except Exception:
-                    continue
-
-            return jsonify({
-                "title": ol_data.get('title', 'Unknown Title'),
-                "authors": ', '.join([a for a in author_names if a]) if author_names else 'Unknown Author',
-                "publisher": ', '.join(ol_data.get('publishers', [])) if ol_data.get('publishers') else 'Unknown Publisher',
-                "publishedDate": ol_data.get('publish_date', 'Unknown Date'),
-                "description": (ol_data.get('description', {}).get('value') if isinstance(ol_data.get('description'), dict) else ol_data.get('description')) or 'No description available',
-                "pageCount": ol_data.get('number_of_pages', 'Unknown'),
-                "price": None,
-                "thumbnail": f"https://covers.openlibrary.org/b/isbn/{clean_isbn}-L.jpg",
-                "isbn": clean_isbn,
-                "source": "openlibrary"
-            })
+        # Iterate through providers until a book is found
+        for provider in providers:
+            book_data = provider(clean_isbn)
+            
+            if book_data:
+                # Add the ISBN back into the response payload
+                book_data["isbn"] = clean_isbn
+                
+                # If a provider found the book but had no cover, assign a default OpenLibrary cover fallback
+                if not book_data.get("thumbnail"):
+                    book_data["thumbnail"] = f"https://covers.openlibrary.org/b/isbn/{clean_isbn}-L.jpg"
+                    
+                return jsonify(book_data)
 
+        # If all providers fail
         return jsonify({"error": f"Kein Buch zu dieser ISBN gefunden: {clean_isbn}"}), 404
         
     except Exception as e:

Web/templates/base.html

@@ -1295,11 +1295,6 @@
                         </li>
                         {% endif %}
                         {% if 'username' in session %}
-                        {% if current_permissions.pages.get('my_borrowed_items', True) %}
-                        <li class="nav-item">
-                            <a class="nav-link quick-link-pill {% if current_path == url_for('my_borrowed_items') %}nav-active{% endif %}" href="{{ url_for('my_borrowed_items') }}" data-tutorial-tip="Hier sehen Sie Ihre bibliotheksbezogenen Ausleihen.">Meine Medien</a>
-                        </li>
-                        {% endif %}
                         {% if current_permissions.pages.get('tutorial_page', True) %}
                         <li class="nav-item">
                             <a class="nav-link quick-link-pill {% if current_path == url_for('tutorial_page') %}nav-active{% endif %}" href="{{ url_for('tutorial_page') }}" data-tutorial-tip="Nutzen Sie das Tutorial, um die Bibliotheksfunktionen kennenzulernen.">Tutorial</a>

Web/templates/library.html

@@ -10,24 +10,6 @@
             <h1>📚 Bibliothek</h1>
             <p class="subtitle">Bücher, CDs und weitere Medien</p>
         </div>
-        
-        <div class="header-controls">
-            <!-- Favorites Toggle -->
-            <div class="view-switch">
-                <button id="favoriteToggle" class="toggle-btn" aria-label="Favoriten anzeigen/verbergen">
-                    <span class="toggle-icon">⭐</span>
-                    <span class="toggle-label">Favoriten</span>
-                </button>
-            </div>
-
-            <!-- View Mode Toggle -->
-            <div class="view-switch">
-                <button id="viewModeToggle" class="toggle-btn" aria-label="Ansichtsmodus wechseln">
-                    <span class="toggle-icon">ㄷ</span>
-                    <span class="toggle-label">Tabelle</span>
-                </button>
-            </div>
-        </div>
     </div>
 
     <!-- Search & Filter Section -->
@@ -205,8 +187,7 @@
         </form>
     </div>
 </div>
-
-<script src="https://cdn.jsdelivr.net/npm/html5-qrcode/minified/html5-qrcode.min.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/@ericblade/quagga2/dist/quagga.js"></script>
 <script>
 // View mode persistence
 const LIBRARY_VIEW_MODE_KEY = 'inventarLibraryViewMode';
@@ -625,50 +606,80 @@ document.getElementById('clearFiltersBtn').addEventListener('click', function()
     closeAllFilters();
 });
 
-// Favorites toggle
-document.getElementById('favoriteToggle').addEventListener('click', function() {
-    this.classList.toggle('open');
-    // TODO: Implement favorites filtering
-});
-
 // Scanner toggle
-let scanner = null;
+// Scanner state tracking
+let isScanning = false; 
+
 document.getElementById('scannerBtn').addEventListener('click', function(e) {
     e.stopPropagation();
     const container = document.getElementById('qrContainer');
     const isOpen = container.style.display !== 'none';
+    const btn = this;
     
     if (isOpen) {
+        // Close the scanner
         container.style.display = 'none';
-        if (scanner) scanner.clear();
-        this.classList.remove('open');
-        this.setAttribute('aria-expanded', 'false');
-    } else {
-        container.style.display = 'block';
-        this.classList.add('open');
-        this.setAttribute('aria-expanded', 'true');
+        Quagga.stop();
+        isScanning = false;
         
-        if (!scanner) {
-            scanner = new Html5Qrcode('qr-reader');
-            scanner.start(
-                { facingMode: "environment" },
-                { fps: 10, qrbox: 250 },
-                onScanSuccess,
-                onScanError
-            );
-        }
+        btn.classList.remove('open');
+        btn.setAttribute('aria-expanded', 'false');
+    } else {
+        // Open the scanner
+        container.style.display = 'block';
+        btn.classList.add('open');
+        btn.setAttribute('aria-expanded', 'true');
+        
+        Quagga.init({
+            inputStream: {
+                name: "Live",
+                type: "LiveStream",
+                // Targets the element where the video stream will inject
+                target: document.querySelector('#qr-reader'), 
+                constraints: {
+                    width: 640,
+                    height: 480,
+                    facingMode: "environment" // Forces back camera
+                },
+            },
+            decoder: {
+                // Optimized for 1D barcodes (e.g., student IDs, member cards)
+                readers: ["code_128_reader", "ean_reader", "code_39_reader", "upc_reader"]
+            } 
+        }, function(err) {
+            if (err) {
+                console.error("Initialization error:", err);
+                alert("Kamera konnte nicht gestartet werden.");
+                return;
+            }
+            Quagga.start();
+            isScanning = true;
+        });
     }
 });
 
-function onScanSuccess(decodedText, decodedResult) {
-    const studentId = decodedText.trim();
+// Single Quagga event listener for successful scans
+Quagga.onDetected(function(data) {
+    const decodedText = data.codeResult.code;
+    const studentId = String(decodedText || '').trim();
+    
+    // Stop scanning immediately to prevent multiple triggers
+    Quagga.stop();
+    isScanning = false;
+    
+    // Reset UI states to closed
+    const container = document.getElementById('qrContainer');
+    const btn = document.getElementById('scannerBtn');
+    if (container) container.style.display = 'none';
+    if (btn) {
+        btn.classList.remove('open');
+        btn.setAttribute('aria-expanded', 'false');
+    }
+    
+    // Route the scanned data to your input
     document.getElementById('studentIdInput').value = studentId;
     alert('Ausweis gescannt: ' + studentId);
-}
-
-function onScanError(error) {
-    // Silently ignore scan errors
-}
+});
 </script>
 
 <style>

Web/templates/main.html

@@ -525,8 +525,7 @@
     
     window.isDebug = false; // Set to true only for development environment
 </script>
-
-<script src="https://unpkg.com/html5-qrcode@2.0.9/dist/html5-qrcode.min.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/@ericblade/quagga2/dist/quagga.js"></script>
 <script>
     // Global state
     const highlightItemId = (window.serverVars && window.serverVars.highlightItemId && window.serverVars.highlightItemId !== 'null')
@@ -535,51 +534,114 @@
     let codeSearchTerm = '';
     let descSearchIds = null; // Set of matching IDs or null when disabled
 
-    // QR scanner toggle setup
-    document.addEventListener('DOMContentLoaded', function() {
-        const scanButton = document.getElementById('scanButton');
+    // Keep track of the scanner state globally/outer scope
+    let isScanning = false; 
+    let activeScannerCallback = null; // Tracks which function currently owns the scanner output
+
+    function startScanner(targetCallback) {
         const qrReader = document.getElementById('qr-reader');
-        let html5QrcodeScanner = null;
+        const statusText = document.getElementById('status');
 
-        if (!scanButton || !qrReader) return;
+        // Store the custom action that should happen when a barcode is found
+        activeScannerCallback = targetCallback;
 
-        const setScannerUi = (isOpen) => {
-            scanButton.classList.toggle('is-active', isOpen);
-            scanButton.setAttribute('aria-expanded', isOpen ? 'true' : 'false');
-            scanButton.textContent = isOpen ? 'Scanner schliessen' : 'Barcode scannen';
-        };
+        // Show the container
+        if (qrReader) qrReader.style.display = 'block';
+        if (statusText) statusText.innerText = "Initializing camera...";
 
-        scanButton.addEventListener('click', function() {
-            if (qrReader.style.display !== 'block') {
-                qrReader.style.display = 'block';
-                
-                html5QrcodeScanner = new Html5QrcodeScanner(
-                    'qr-reader', { fps: 10, qrbox: 250 }
-                );
-                
-                html5QrcodeScanner.render((decodedText) => {
-                    html5QrcodeScanner.clear();
-                    qrReader.style.display = 'none';
-                    
-                    // Put scanned code into the search box and trigger search
-                    const searchInput = document.getElementById('code-search');
-                    if (searchInput) {
-                        searchInput.value = decodedText;
-                        searchByCode();
-                    }
-
-                    setScannerUi(false);
-                });
-
-                setScannerUi(true);
-            } else {
-                if (html5QrcodeScanner) {
-                    html5QrcodeScanner.clear();
-                }
-                qrReader.style.display = 'none';
-                setScannerUi(false);
+        Quagga.init({
+            inputStream: {
+                name: "Live",
+                type: "LiveStream",
+                // Make sure this targets your correct HTML container element 
+                target: document.querySelector('#scanner-container'), 
+                constraints: {
+                    width: 640,
+                    height: 480,
+                    facingMode: "environment" // Force rear camera
+                },
+            },
+            decoder: {
+                // Your required formats mapped to Quagga2 reader strings
+                readers: ["code_128_reader", "ean_reader", "code_39_reader", "upc_reader"]
+            } 
+        }, function(err) {
+            if (err) {
+                console.error("Initialization error:", err);
+                if (statusText) statusText.innerText = "Camera Error";
+                return;
             }
+
+            Quagga.start();
+            isScanning = true;
+
+            // If we are using the main search button, manage its UI state
+            if (!targetCallback) {
+                setScannerUi(true);
+            }
+
+            if (statusText) statusText.innerText = "Scanning...";
         });
+    }
+
+    function stopScanner() {
+        Quagga.stop();
+        isScanning = false;
+        activeScannerCallback = null; // Reset the callback routing
+
+        const qrReader = document.getElementById('qr-reader');
+        if (qrReader) qrReader.style.display = 'none';
+
+        setScannerUi(false);
+    }
+
+    function setScannerUi(isOpen) {
+        const scanBtn = document.getElementById('scanButton');
+        if (!scanBtn) return;
+
+        scanBtn.classList.toggle('is-active', isOpen);
+        scanBtn.setAttribute('aria-expanded', isOpen ? 'true' : 'false');
+        scanBtn.textContent = isOpen ? 'Scanner schliessen' : 'Barcode scannen';
+    }
+
+    // Unified global reader callback
+    Quagga.onDetected(function(data) {
+        const barcode = String(data.codeResult.code || '').trim();
+        console.log("Barcode detected:", barcode);
+
+        // Keep a local reference to the active callback before shutting down the engine
+        const currentCallback = activeScannerCallback;
+
+        // Critical: Stop scanning immediately to prevent multiple triggers
+        stopScanner();
+
+        // Route data based on who opened the scanner
+        if (typeof currentCallback === "function") {
+            // Send data directly to the specific edit field's logic
+            currentCallback(barcode);
+        } else {
+            // Fallback Default: Main search box logic
+            const resultText = document.getElementById('barcode-result');
+            if (resultText) resultText.innerText = barcode;
+
+            const searchInput = document.getElementById('code-search');
+            if (searchInput) {
+                searchInput.value = barcode;
+                if (typeof searchByCode === "function") {
+                    searchByCode();
+                }
+            }
+        }
+    });
+
+    // Event Listener for the main standalone search button
+    document.getElementById('scanButton')?.addEventListener('click', function() {
+        if (!isScanning) {
+            // Pass null so it defaults to filling the standard search box
+            startScanner(null); 
+        } else {
+            stopScanner();
+        }
     });
 
     // Return preferred primary and fallback image URLs based on extension

Web/templates/main_admin.html

@@ -2436,7 +2436,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
         <div class="qr-container">
             <button id="scanButton" class="scan-button" aria-controls="qr-reader" aria-expanded="false">Barcode scannen</button>
             <div id="qr-reader" style="display: none;">
-                <h3>Status: <span id="status">Ready</span></h3>
+                <h3>Status: <span id="status">Bereit</span></h3>
                 <div id="scanner-container"></div>
             </div>
         </div>
@@ -2733,7 +2733,6 @@ document.addEventListener('DOMContentLoaded', ()=>{
     window.isDebug = false; // Set to true only for development environment
 </script>
 <script src="https://cdn.jsdelivr.net/npm/@ericblade/quagga2/dist/quagga.js"></script>
-<script src="/static/js/scanner.js"></script>
 <script>
     // Function to check if a file is a video
     function isVideoFile(filename) {
@@ -2771,14 +2770,18 @@ document.addEventListener('DOMContentLoaded', ()=>{
         // No-op in production
         return;
     }
-    
+
     // Keep track of the scanner state globally/outer scope
     let isScanning = false; 
+    let activeScannerCallback = null; // Tracks which function currently owns the scanner output
 
-    function startScanner() {
+    function startScanner(targetCallback) {
         const qrReader = document.getElementById('qr-reader');
         const statusText = document.getElementById('status');
 
+        // Store the custom action that should happen when a barcode is found
+        activeScannerCallback = targetCallback;
+
         // Show the container
         if (qrReader) qrReader.style.display = 'block';
         if (statusText) statusText.innerText = "Initializing camera...";
@@ -2808,7 +2811,12 @@ document.addEventListener('DOMContentLoaded', ()=>{
 
             Quagga.start();
             isScanning = true;
-            setScannerUi(true);
+
+            // If we are using the main search button, manage its UI state
+            if (!targetCallback) {
+                setScannerUi(true);
+            }
+
             if (statusText) statusText.innerText = "Scanning...";
         });
     }
@@ -2816,6 +2824,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
     function stopScanner() {
         Quagga.stop();
         isScanning = false;
+        activeScannerCallback = null; // Reset the callback routing
 
         const qrReader = document.getElementById('qr-reader');
         if (qrReader) qrReader.style.display = 'none';
@@ -2832,37 +2841,46 @@ document.addEventListener('DOMContentLoaded', ()=>{
         scanBtn.textContent = isOpen ? 'Scanner schliessen' : 'Barcode scannen';
     }
 
-    // 4. Quagga event listener for successful scans
+    // Unified global reader callback
     Quagga.onDetected(function(data) {
-        const barcode = data.codeResult.code;
+        const barcode = String(data.codeResult.code || '').trim();
         console.log("Barcode detected:", barcode);
 
+        // Keep a local reference to the active callback before shutting down the engine
+        const currentCallback = activeScannerCallback;
+
         // Critical: Stop scanning immediately to prevent multiple triggers
         stopScanner();
 
-        // Update your results display if you have them
-        const resultText = document.getElementById('barcode-result');
-        if (resultText) resultText.innerText = barcode;
+        // Route data based on who opened the scanner
+        if (typeof currentCallback === "function") {
+            // Send data directly to the specific edit field's logic
+            currentCallback(barcode);
+        } else {
+            // Fallback Default: Main search box logic
+            const resultText = document.getElementById('barcode-result');
+            if (resultText) resultText.innerText = barcode;
 
-        // Put the scanned code in the search box
-        const searchInput = document.getElementById('code-search');
-        if (searchInput) {
-            searchInput.value = barcode;
-            // Trigger your automatic search
-            if (typeof searchByCode === "function") {
-                searchByCode();
+            const searchInput = document.getElementById('code-search');
+            if (searchInput) {
+                searchInput.value = barcode;
+                if (typeof searchByCode === "function") {
+                    searchByCode();
+                }
             }
         }
     });
 
-    // 5. Wire up your Toggle Button click event
-    document.getElementById('scanButton').addEventListener('click', function() {
+    // Event Listener for the main standalone search button
+    document.getElementById('scanButton')?.addEventListener('click', function() {
         if (!isScanning) {
-            startScanner();
+            // Pass null so it defaults to filling the standard search box
+            startScanner(null); 
         } else {
             stopScanner();
         }
     });
+
     function scanIntoEditCode() {
         const qrReader = document.getElementById('qr-reader');
         const editCodeInput = document.getElementById('edit-code4');
@@ -2871,37 +2889,21 @@ document.addEventListener('DOMContentLoaded', ()=>{
             return;
         }
 
-        if (qrReader.style.display !== 'none') {
-            if (hybridScanner) {
-                hybridScanner.stop();
-                hybridScanner = null;
-            }
-            qrReader.style.display = 'none';
+        // Toggle close if it's already running
+        if (isScanning && qrReader.style.display !== 'none') {
+            stopScanner();
             scanEditBtn.textContent = 'Barcode scannen';
             return;
         }
 
-        qrReader.style.display = 'block';
         scanEditBtn.textContent = 'Scanner schließen';
-        hybridScanner = new HybridScanner({
-            videoId: 'qr-reader-video',
-            canvasId: 'qr-reader-canvas',
-            formats: ['CODE_128', 'CODE_39', 'QR_CODE'],
-            fps: 10,
-            facingMode: 'environment',
-            onSuccess: function(decodedText) {
-                hybridScanner.stop();
-                qrReader.style.display = 'none';
-                editCodeInput.value = String(decodedText || '').trim();
-                validateCodeField(editCodeInput, document.getElementById('edit-item-id')?.value || null);
-                scanEditBtn.textContent = 'Barcode scannen';
-            },
-            onError: function(error) {
-                console.error('Scanner error:', error);
-            }
+
+        // Start scanner with custom logic mapping to the Code input field
+        startScanner(function(decodedText) {
+            editCodeInput.value = decodedText;
+            validateCodeField(editCodeInput, document.getElementById('edit-item-id')?.value || null);
+            scanEditBtn.textContent = 'Barcode scannen';
         });
-        
-        hybridScanner.start();
     }
 
     function scanIntoEditIsbn() {
@@ -2912,39 +2914,23 @@ document.addEventListener('DOMContentLoaded', ()=>{
             return;
         }
 
-        if (qrReader.style.display !== 'none') {
-            if (hybridScanner) {
-                hybridScanner.stop();
-                hybridScanner = null;
-            }
-            qrReader.style.display = 'none';
+        // Toggle close if it's already running
+        if (isScanning && qrReader.style.display !== 'none') {
+            stopScanner();
             scanIsbnBtn.textContent = 'ISBN scannen';
             return;
         }
 
-        qrReader.style.display = 'block';
         scanIsbnBtn.textContent = 'Scanner schließen';
-        hybridScanner = new HybridScanner({
-            videoId: 'qr-reader-video',
-            canvasId: 'qr-reader-canvas',
-            formats: ['ISBN', 'EAN_13', 'EAN_8', 'QR_CODE'],
-            fps: 10,
-            facingMode: 'environment',
-            onSuccess: function(decodedText) {
-                hybridScanner.stop();
-                qrReader.style.display = 'none';
-                editIsbnInput.value = String(decodedText || '').trim();
-                scanIsbnBtn.textContent = 'ISBN scannen';
-                if (typeof fetchBookInfo === 'function') {
-                    fetchBookInfo('edit');
-                }
-            },
-            onError: function(error) {
-                console.error('Scanner error:', error);
+
+        // Start scanner with custom logic mapping to the ISBN input field
+        startScanner(function(decodedText) {
+            editIsbnInput.value = decodedText;
+            scanIsbnBtn.textContent = 'ISBN scannen';
+            if (typeof fetchBookInfo === 'function') {
+                fetchBookInfo('edit');
             }
         });
-        
-        hybridScanner.start();
     }
 
     function rebuildFilter3Options() {

Web/templates/upload_admin.html

@@ -831,7 +831,7 @@
                             <!-- Options will be loaded by JavaScript -->
                         </select>
                     </div>
-                    <div class="form-group">
+                    <div class="formupload_admin-group">
                         <label for="filter2-4">Wert 4:</label>
                         <select id="filter2-4" name="filter2" class="filter-dropdown-select">
                             <option value="">-- Optional --</option>
@@ -869,25 +869,41 @@
                 <label for="anschaffungskosten">Anschaffungskosten (€)</label>
                 <input id="anschaffungskosten" name="anschaffungskosten">
             </div>
-            <div class="form-group">
-                <label for="code_4">Code</label>
-                <div style="display:flex; gap:8px; flex-wrap:wrap; align-items:center;">
-                    <input id="code_4" name="code_4">
-                    <button type="button" id="scan-code4-btn" class="fetch-isbn-button">Barcode scannen</button>
+           <div class="form-group">
+                <label for="scan_mode">Erfassungs-Modus:</label>
+                <select id="scan_mode" name="scan_mode" class="form-control" onchange="toggleScanMode()">
+                    <option value="single">Einzel-Code (Scanner stoppt nach 1 Scan)</option>
+                    <option value="continuous">Fortlaufend scannen (Mehrere Codes nacheinander)</option>
+                    <option value="range">Code-Bereich generieren (z.B. ABC-001 bis ABC-010)</option>
+                </select>
+            </div>
+
+            <div id="range_generator_group" class="form-group" style="display:none; background: #f9f9f9; padding: 15px; border-radius: 5px; border: 1px solid #ddd; margin-bottom: 15px;">
+                <label style="font-weight: bold;">Code-Bereich automatisch generieren:</label>
+                <div style="display: flex; gap: 10px; margin-bottom: 10px; align-items: center;">
+                    <input type="text" id="range_prefix" placeholder="Präfix (z.B. IT-)" class="form-control" style="flex: 2;">
+                    <input type="number" id="range_start" placeholder="Start (z.B. 1)" class="form-control" style="flex: 1;">
+                    <span style="font-weight: bold;">bis</span>
+                    <input type="text" id="range_end" placeholder="Ende (z.B. 020)" class="form-control" style="flex: 1;">
                 </div>
-                <small style="display:block; color:#666;">Einzelcode manuell setzen oder per Scanner erfassen.</small>
-                <div id="code4-scanner" style="width:100%; max-width:520px; display:none; margin-top:10px;"></div>
-                <small id="code4-scan-status" style="display:block; color:#666; margin-top:6px;"></small>
+                <small style="display:block; color:#666; margin-bottom: 10px;">Tipp: Die Anzahl der Ziffern im "Ende"-Feld bestimmt die führenden Nullen (z.B. Ende "050" macht aus Start "1" einen "001").</small>
+                <button type="button" class="btn btn-secondary" onclick="generateCodeRange()">Bereich generieren & einfügen</button>
             </div>
-            <div class="form-group">
-                <label for="item_count">Anzahl dieser Sorte</label>
-                <input type="number" id="item_count" name="item_count" min="1" max="100" value="1">
-                <small style="display:block; color:#666;">Es werden eigene Items erstellt, aber in der Übersicht als ein Artikel gebündelt angezeigt.</small>
+
+            <div class="form-group" id="primary_code_group">
+                <label for="code_4">Basis-Code</label>
+                <div style="display: flex; gap: 10px;">
+                    <input type="text" id="code_4" name="code_4" class="form-control" placeholder="Haupt-Barcode" required>
+                    <button type="button" id="scan-code4-btn" class="btn btn-primary">Barcode scannen</button>
+                </div>
+                <div id="code4-scanner" style="display:none; margin-top: 10px;"></div>
+                <small id="code4-scan-status" class="form-text text-muted"></small>
             </div>
-            <div class="form-group">
-                <label for="individual_codes">Einzelcodes (optional, je Zeile ein Code)</label>
-                <textarea id="individual_codes" name="individual_codes" rows="4" placeholder="z.B.\nABC-001\nABC-002"></textarea>
-                <small style="display:block; color:#666;">Bei Anzahl > 1 können hier individuelle Codes pro Item gesetzt werden. Der Scanner setzt immer zuerst den Basis-Code im Feld oben; weitere Einzelcodes können hier bei Bedarf manuell ergänzt werden.</small>
+
+            <div class="form-group" id="individual_codes_group">
+                <label for="individual_codes">Weitere Einzelcodes (je Zeile ein Code)</label>
+                <textarea id="individual_codes" name="individual_codes" rows="6" placeholder="z.B.&#10;ABC-001&#10;ABC-002" class="form-control"></textarea>
+                <small style="display:block; color:#666; margin-top: 5px;">Bei Anzahl > 1 können hier individuelle Codes pro Item gesetzt werden. Der Scanner setzt immer zuerst den Basis-Code im Feld oben; weitere Einzelcodes werden hier angehängt.</small>
             </div>
             <!-- Image upload (hidden for library mode) -->
             <div class="form-group" {% if show_library_features %}style="display:none;"{% endif %}>
@@ -970,8 +986,7 @@
         document.getElementById('csv-help-modal').style.display = 'none';
     }
 </script>
-
-<script src="https://unpkg.com/html5-qrcode@2.0.9/dist/html5-qrcode.min.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/@ericblade/quagga2/dist/quagga.js"></script>
 <script>
     const libraryModuleEnabled = {{ 'true' if library_module_enabled else 'false' }};
 
@@ -984,12 +999,12 @@
 
     // Global variable to store fetched book data
     let currentBookData = null;
-    let code4ScannerInstance = null;
-    let code4ScannerRunning = false;
+    
+    // Quagga2 engine state management properties
+    let scannerRunning = false;
+    let activeScannerCallback = null; // Dynamically handles routing data to the active caller field
     let code4LastScanned = '';
     let code4LastScannedAt = 0;
-    let isbnScannerInstance = null;
-    let isbnScannerRunning = false;
 
     function setCode4ScanStatus(message, isError = false) {
         const statusEl = document.getElementById('code4-scan-status');
@@ -1042,58 +1057,240 @@
         statusEl.style.color = '#b00020';
     }
 
-    function startCode4Scanner() {
-        const scannerBox = document.getElementById('code4-scanner');
-        const scanButton = document.getElementById('scan-code4-btn');
-        const codeField = document.getElementById('code_4');
-        if (!scannerBox || !scanButton || !codeField) return;
-
-        // Stop ISBN scanner if currently running to avoid camera conflicts.
-        if (isbnScannerRunning && isbnScannerInstance) {
-            isbnScannerInstance.clear().catch(() => {});
-            const isbnScannerBox = document.getElementById('isbn-scanner');
-            const isbnScanButton = document.getElementById('scan-isbn-btn');
-            if (isbnScannerBox) isbnScannerBox.style.display = 'none';
-            if (isbnScanButton) isbnScanButton.textContent = 'ISBN scannen';
-            isbnScannerRunning = false;
+    // Centered Quagga2 Engine Initialization Pattern
+    function runEngineInitialization(targetSelector, activeCallback, completionMsg, errorStatusSetter) {
+        if (scannerRunning) {
+            Quagga.stop();
+            scannerRunning = false;
         }
 
-        if (code4ScannerRunning && code4ScannerInstance) {
-            code4ScannerInstance.clear().catch(() => {});
-            scannerBox.style.display = 'none';
-            scanButton.textContent = 'Barcode scannen';
-            code4ScannerRunning = false;
-            setCode4ScanStatus('Scanner gestoppt.');
-            return;
-        }
+        activeScannerCallback = activeCallback;
 
-        scannerBox.style.display = 'block';
-        scanButton.textContent = 'Scanner stoppen';
-        code4ScannerInstance = new Html5QrcodeScanner('code4-scanner', { 
-            fps: 10, 
-            qrbox: 250,
-            rememberLastUsedCamera: true
-        });
-        code4ScannerRunning = true;
-        setCode4ScanStatus('Scanner läuft. Der Scan wird im Basis-Codefeld übernommen.');
-
-        code4ScannerInstance.render((decodedText) => {
-            const scannedCode = String(decodedText || '').trim();
-            if (!scannedCode) return;
-
-            const now = Date.now();
-            if (scannedCode === code4LastScanned && (now - code4LastScannedAt) < 1500) {
+        Quagga.init({
+            inputStream: {
+                name: "Live",
+                type: "LiveStream",
+                target: document.querySelector(targetSelector), 
+                constraints: {
+                    width: 640,
+                    height: 480,
+                    facingMode: "environment" // Force rear camera lenses
+                },
+            },
+            decoder: {
+                readers: ["code_128_reader", "ean_reader", "code_39_reader", "upc_reader"]
+            } 
+        }, function(err) {
+            if (err) {
+                console.error("Initialization error:", err);
+                errorStatusSetter("Kamera konnte nicht gestartet werden.", true);
                 return;
             }
-            code4LastScanned = scannedCode;
-            code4LastScannedAt = now;
 
-            codeField.value = scannedCode;
-            validateCodeField(codeField);
-            setCode4ScanStatus(`Code_4 gesetzt: ${scannedCode}`);
-        }, () => {});
+            Quagga.start();
+            scannerRunning = true;
+            errorStatusSetter(completionMsg, false);
+        });
     }
 
+    function killScannerHardware() {
+        if (!scannerRunning) return;
+        Quagga.stop();
+        scannerRunning = false;
+        activeScannerCallback = null;
+    }
+
+    // Unified tracking capture listener
+    Quagga.onDetected(function(data) {
+        if (!data || !data.codeResult || !data.codeResult.code) return;
+        
+        const rawBarcode = String(data.codeResult.code || '').trim();
+        const currentTargetCallback = activeScannerCallback;
+
+        if (typeof currentTargetCallback === "function") {
+            currentTargetCallback(rawBarcode);
+        }
+    });
+
+    // Globale Variablen für den Scanner-Status (falls nicht schon woanders definiert)
+let code4LastScanned = '';
+let code4LastScannedAt = 0;
+
+/**
+ * Schaltet das UI basierend auf dem ausgewählten Modus um
+ */
+function toggleScanMode() {
+    const mode = document.getElementById('scan_mode').value;
+    const rangeGroup = document.getElementById('range_generator_group');
+    const scanButton = document.getElementById('scan-code4-btn');
+    const scannerBox = document.getElementById('code4-scanner');
+    
+    // Scanner stoppen, falls der Modus gewechselt wird und er noch läuft
+    if (scannerBox && scannerBox.style.display !== 'none') {
+        if (typeof killScannerHardware === 'function') killScannerHardware();
+        scannerBox.style.display = 'none';
+        if (scanButton) scanButton.textContent = 'Barcode scannen';
+    }
+
+    if (mode === 'range') {
+        rangeGroup.style.display = 'block';
+        if(scanButton) scanButton.style.display = 'none'; // Verstecke Scanner im Range-Modus
+    } else {
+        rangeGroup.style.display = 'none';
+        if(scanButton) scanButton.style.display = 'inline-block';
+    }
+}
+
+/**
+ * Generiert eine Liste von Codes basierend auf den Eingaben
+ */
+function generateCodeRange() {
+    const prefix = document.getElementById('range_prefix').value.trim();
+    const startStr = document.getElementById('range_start').value.trim();
+    const endStr = document.getElementById('range_end').value.trim();
+    
+    const start = parseInt(startStr, 10);
+    const end = parseInt(endStr, 10);
+    
+    // Die Länge des End-Wertes bestimmt das Padding (die führenden Nullen)
+    // Beispiel: Ende = "050" -> Länge 3 -> "001", "002", etc.
+    const paddingLength = endStr.length; 
+
+    if (isNaN(start) || isNaN(end) || start > end) {
+        alert("Bitte gültige Zahlen für Start und Ende eingeben. Der Startwert darf nicht größer als der Endwert sein.");
+        return;
+    }
+
+    let generatedCodes = [];
+    for (let i = start; i <= end; i++) {
+        // Nullen auffüllen
+        let numStr = i.toString().padStart(paddingLength, '0');
+        generatedCodes.push(`${prefix}${numStr}`);
+    }
+
+    const codeField = document.getElementById('code_4');
+    const individualCodesArea = document.getElementById('individual_codes');
+
+    if (generatedCodes.length > 0) {
+        // 1. Basis-Code setzen (falls leer oder wenn wir komplett neu generieren)
+        if (!codeField.value || confirm("Soll der aktuelle Basis-Code überschrieben werden?")) {
+            codeField.value = generatedCodes[0];
+            if (typeof validateCodeField === 'function') validateCodeField(codeField);
+            generatedCodes.shift(); // Den ersten aus dem Array entfernen, da er im Basis-Feld steht
+        }
+        
+        // 2. Den Rest in die Textarea einfügen
+        if (generatedCodes.length > 0) {
+            let existing = individualCodesArea.value.trim();
+            // Wenn schon was drin steht, machen wir einen Zeilenumbruch, sonst nicht
+            individualCodesArea.value = existing ? existing + '\n' + generatedCodes.join('\n') : generatedCodes.join('\n');
+        }
+        
+        // Visuelles Feedback
+        alert(`Bereich erfolgreich generiert! (${end - start + 1} Codes)`);
+    }
+}
+
+/**
+ * Scanner-Funktion (Single & Continuous Modus)
+ */
+function startCode4Scanner() {
+    const scannerBox = document.getElementById('code4-scanner');
+    const scanButton = document.getElementById('scan-code4-btn');
+    const codeField = document.getElementById('code_4');
+    const individualCodesArea = document.getElementById('individual_codes');
+    const scanMode = document.getElementById('scan_mode').value;
+
+    if (!scannerBox || !scanButton || !codeField) return;
+
+    // Beende evtl. laufenden ISBN Scanner
+    const isbnScannerBox = document.getElementById('isbn-scanner');
+    if (isbnScannerBox && isbnScannerBox.style.display !== 'none') {
+        if (typeof killScannerHardware === 'function') killScannerHardware();
+        isbnScannerBox.style.display = 'none';
+        const isbnScanButton = document.getElementById('scan-isbn-btn');
+        if (isbnScanButton) isbnScanButton.textContent = 'ISBN scannen';
+        if (typeof setIsbnScanStatus === 'function') setIsbnScanStatus('Scanner gestoppt.');
+    }
+
+    // Scanner ausschalten, wenn er bereits läuft
+    if (scannerBox.style.display !== 'none') {
+        if (typeof killScannerHardware === 'function') killScannerHardware();
+        scannerBox.style.display = 'none';
+        scanButton.textContent = 'Barcode scannen';
+        if (typeof setCode4ScanStatus === 'function') setCode4ScanStatus('Scanner gestoppt.');
+        return;
+    }
+
+    // Scanner starten
+    scannerBox.style.display = 'block';
+    scanButton.textContent = scanMode === 'continuous' ? 'Fortlaufenden Scan stoppen' : 'Scanner stoppen';
+    if (typeof setCode4ScanStatus === 'function') setCode4ScanStatus('Scanner initialisiert. Richte die Kamera auf den Barcode...');
+
+    if (typeof runEngineInitialization === 'function') {
+        runEngineInitialization(
+            '#code4-scanner', 
+            function(decodedText) {
+                const now = Date.now();
+                // Verhindere Doppel-Scans desselben Codes innerhalb von 1.5 Sekunden
+                if (decodedText === code4LastScanned && (now - code4LastScannedAt) < 1500) {
+                    return;
+                }
+                code4LastScanned = decodedText;
+                code4LastScannedAt = now;
+
+                if (scanMode === 'single') {
+                    // VERHALTEN: Einzel-Scan
+                    if (typeof killScannerHardware === 'function') killScannerHardware();
+                    scannerBox.style.display = 'none';
+                    scanButton.textContent = 'Barcode scannen';
+
+                    codeField.value = decodedText;
+                    if (typeof validateCodeField === 'function') validateCodeField(codeField);
+                    if (typeof setCode4ScanStatus === 'function') setCode4ScanStatus(`Code gesetzt: ${decodedText}`);
+                    
+                } else if (scanMode === 'continuous') {
+                    // VERHALTEN: Fortlaufender Scan
+                    let currentAreaCodes = individualCodesArea.value.split('\n').map(c => c.trim()).filter(c => c !== '');
+                    
+                    if (!codeField.value) {
+                        // Basis-Code setzen, falls noch leer
+                        codeField.value = decodedText;
+                        if (typeof validateCodeField === 'function') validateCodeField(codeField);
+                        if (typeof setCode4ScanStatus === 'function') setCode4ScanStatus(`Basis-Code gesetzt: ${decodedText}`);
+                    } else if (!currentAreaCodes.includes(decodedText) && codeField.value !== decodedText) {
+                        // In Textarea anhängen, falls Code noch nicht existiert
+                        individualCodesArea.value += (individualCodesArea.value ? '\n' : '') + decodedText;
+                        if (typeof setCode4ScanStatus === 'function') setCode4ScanStatus(`Zusatz-Code erfasst: ${decodedText}`);
+                        
+                        // Audio-Feedback für kontinuierliches Scannen (optional, aber sehr hilfreich)
+                        try {
+                            const audioCtx = new (window.AudioContext || window.webkitAudioContext)();
+                            const oscillator = audioCtx.createOscillator();
+                            const gainNode = audioCtx.createGain();
+                            oscillator.connect(gainNode);
+                            gainNode.connect(audioCtx.destination);
+                            oscillator.type = 'sine';
+                            oscillator.frequency.value = 800; // Hoher Beep
+                            gainNode.gain.setValueAtTime(0.1, audioCtx.currentTime);
+                            oscillator.start();
+                            oscillator.stop(audioCtx.currentTime + 0.1);
+                        } catch (e) {
+                            console.log("Audio feedback not supported");
+                        }
+                    } else {
+                        if (typeof setCode4ScanStatus === 'function') setCode4ScanStatus(`Code ${decodedText} wurde bereits gescannt.`);
+                    }
+                }
+            },
+            'Scanner läuft. Richte die Kamera auf den Barcode.',
+            setCode4ScanStatus
+        );
+    } else {
+        console.error("runEngineInitialization is not defined. Ensure your scanner script is loaded.");
+    }
+}
+
     function startIsbnScanner() {
         if (!libraryModuleEnabled) {
             setIsbnScanStatus('Bibliotheks-Modul ist deaktiviert.', true);
@@ -1104,59 +1301,49 @@
         const isbnField = document.getElementById('isbn');
         if (!scannerBox || !scanButton || !isbnField) return;
 
-        // Stop Code_4 scanner if currently running to avoid camera conflicts.
-        if (code4ScannerRunning && code4ScannerInstance) {
-            code4ScannerInstance.clear().catch(() => {});
-            const codeScannerBox = document.getElementById('code4-scanner');
-            const codeScanButton = document.getElementById('scan-code4-btn');
+        // Automatically clean up running Base Code_4 scanner to prevent track multi-binding
+        const codeScannerBox = document.getElementById('code4-scanner');
+        const codeScanButton = document.getElementById('scan-code4-btn');
+        if (codeScannerBox && codeScannerBox.style.display !== 'none') {
+            killScannerHardware();
             if (codeScannerBox) codeScannerBox.style.display = 'none';
             if (codeScanButton) codeScanButton.textContent = 'Barcode scannen';
-            code4ScannerRunning = false;
             setCode4ScanStatus('Scanner gestoppt.');
         }
 
-        if (isbnScannerRunning && isbnScannerInstance) {
-            isbnScannerInstance.clear().catch(() => {});
+        if (scannerBox.style.display !== 'none') {
+            killScannerHardware();
             scannerBox.style.display = 'none';
             scanButton.textContent = 'ISBN scannen';
-            isbnScannerRunning = false;
             setIsbnScanStatus('Scanner gestoppt.');
             return;
         }
 
         scannerBox.style.display = 'block';
         scanButton.textContent = 'Scanner stoppen';
-        isbnScannerInstance = new Html5QrcodeScanner('isbn-scanner', {
-            fps: 10,
-            qrbox: 250,
-            rememberLastUsedCamera: true
-        });
-        isbnScannerRunning = true;
-        setIsbnScanStatus('Scanner läuft. Bitte ISBN-Code erfassen.');
 
-        isbnScannerInstance.render((decodedText) => {
-            const scannedCode = String(decodedText || '').trim();
-            if (!scannedCode) return;
+        runEngineInitialization(
+            '#isbn-scanner',
+            function(decodedText) {
+                killScannerHardware();
+                scannerBox.style.display = 'none';
+                scanButton.textContent = 'ISBN scannen';
 
-            const normalizedIsbn = normalizeIsbnClient(scannedCode);
-            isbnField.value = normalizedIsbn || scannedCode;
-            updateIsbnLiveValidation();
-            if (normalizedIsbn) {
-                setIsbnScanStatus(`ISBN gesetzt: ${normalizedIsbn}`);
-            } else {
-                setIsbnScanStatus('Kein gültiges ISBN-Format erkannt, der gescannte Wert bleibt aber im Feld.', true);
-            }
+                const normalizedIsbn = normalizeIsbnClient(decodedText);
+                isbnField.value = normalizedIsbn || decodedText;
+                updateIsbnLiveValidation();
 
-            isbnScannerInstance.clear().catch(() => {});
-            scannerBox.style.display = 'none';
-            scanButton.textContent = 'ISBN scannen';
-            isbnScannerRunning = false;
-
-            if (normalizedIsbn) {
-                // Automatically load book metadata after a valid ISBN scan.
-                fetchBookInfo('upload');
-            }
-        }, () => {});
+                if (normalizedIsbn) {
+                    setIsbnScanStatus(`ISBN gesetzt: ${normalizedIsbn}`);
+                    // Automatically load book metadata after a valid ISBN scan.
+                    fetchBookInfo('upload');
+                } else {
+                    setIsbnScanStatus('Kein gültiges ISBN-Format erkannt, der gescannte Wert bleibt aber im Feld.', true);
+                }
+            },
+            'Scanner läuft. Bitte ISBN-Code erfassen.',
+            setIsbnScanStatus
+        );
     }
 
     // Load predefined filter values for dropdowns
@@ -1558,6 +1745,7 @@
         }, 10000);
     }
 
+    // Exported function for use within parent layout fields
     function validateCodeField(input, excludeId = null) {
         const code = input.value.trim();
         
@@ -1732,188 +1920,11 @@
             if (typeof duplicateData.images === 'string') {
                 try {
                     duplicateData.images = JSON.parse(duplicateData.images);
-                    console.log("Parsed images from string:", duplicateData.images);
                 } catch (e) {
-                    console.warn("Failed to parse images string, using as single item:", duplicateData.images);
-                    duplicateData.images = [duplicateData.images];
+                    console.error("Error parsing duplicate images array:", e);
                 }
             }
-            console.log(`Final duplicateData.images (${Array.isArray(duplicateData.images) ? 'array' : typeof duplicateData.images}):`, duplicateData.images);
-        }
-    }
-    
-    // Then check for sessionStorage data (takes priority)
-    const sessionData = sessionStorage.getItem('duplicateItemData');
-    if (sessionData) {
-        try {
-            duplicateData = JSON.parse(sessionData);
-            sessionStorage.removeItem('duplicateItemData'); // Clean up
-            console.log("Session storage duplicate data:", duplicateData);
-        } catch (e) {
-            console.error('Error parsing session duplicate data:', e);
-        }
-    }
-    
-    // Function to prefill form with duplicate data
-    function prefillFormWithDuplicateData() {
-        if (!duplicateData) return;
-        
-        // Fill basic fields
-        const nameField = document.getElementById('name');
-        if (nameField && duplicateData.name) nameField.value = duplicateData.name;
-        
-        const descField = document.getElementById('beschreibung');
-        if (descField && duplicateData.description) descField.value = duplicateData.description;
-        
-        const yearField = document.getElementById('anschaffungsjahr');
-        if (yearField && duplicateData.year) yearField.value = duplicateData.year;
-        
-        const costField = document.getElementById('anschaffungskosten');
-        if (costField && duplicateData.cost) costField.value = duplicateData.cost;
-        
-        // Fill location dropdown
-        const locationField = document.getElementById('ort');
-        if (locationField && duplicateData.location) {
-            // Wait for locations to load, then set value
-            setTimeout(() => {
-                locationField.value = duplicateData.location;
-            }, 100);
-        }
-        
-        // Fill filter arrays - handle up to 4 values per filter type
-        setTimeout(() => {
-            // Filter 1 (Unterrichtsfach)
-            if (duplicateData.filter1 && Array.isArray(duplicateData.filter1)) {
-                for (let j = 1; j <= Math.min(4, duplicateData.filter1.length); j++) {
-                    const filterField = document.getElementById(`filter1-${j}`);
-                    if (filterField && duplicateData.filter1[j-1]) {
-                        filterField.value = duplicateData.filter1[j-1];
-                    }
-                }
-            }
-            
-            // Filter 2 (Jahrgangsstufe)
-            if (duplicateData.filter2 && Array.isArray(duplicateData.filter2)) {
-                for (let j = 1; j <= Math.min(4, duplicateData.filter2.length); j++) {
-                    const filterField = document.getElementById(`filter2-${j}`);
-                    if (filterField && duplicateData.filter2[j-1]) {
-                        filterField.value = duplicateData.filter2[j-1];
-                    }
-                }
-            }
-            
-            // Filter 3 (Thema) - text inputs
-            if (duplicateData.filter3 && Array.isArray(duplicateData.filter3)) {
-                for (let j = 1; j <= Math.min(4, duplicateData.filter3.length); j++) {
-                    const filterField = document.getElementById(`filter3-${j}`);
-                    if (filterField && duplicateData.filter3[j-1]) {
-                        filterField.value = duplicateData.filter3[j-1];
-                    }
-                }
-            }
-        }, 200); // Wait for filter options to load
-        
-        // Handle images - add hidden inputs for duplicate images
-        if (duplicateData.images && duplicateData.images.length > 0) {
-            console.log("Duplicate images data:", duplicateData.images);
-            const form = document.querySelector('form[action*="upload_item"]');
-            if (form) {
-                // Add hidden field to indicate duplication
-                const isDuplicatingField = document.createElement('input');
-                isDuplicatingField.type = 'hidden';
-                isDuplicatingField.name = 'is_duplicating';
-                isDuplicatingField.value = 'true';
-                form.appendChild(isDuplicatingField);
-                
-                // Add each image as a duplicate image
-                const images = duplicateData.images || [];
-                console.log(`Adding ${images.length} images as hidden fields`);
-                
-                if (Array.isArray(images)) {
-                    images.forEach((imageName, index) => {
-                        if (imageName) {
-                            console.log(`Adding duplicate image ${index}: ${imageName}`);
-                            const imageField = document.createElement('input');
-                            imageField.type = 'hidden';
-                            imageField.name = 'duplicate_images';
-                            imageField.value = imageName;
-                            form.appendChild(imageField);
-                        }
-                    });
-                } else {
-                    console.warn("Images is not an array:", images);
-                    // Try to handle as single item if it's a string
-                    if (typeof images === 'string' && images) {
-                        console.log("Adding single image:", images);
-                        const imageField = document.createElement('input');
-                        imageField.type = 'hidden';
-                        imageField.name = 'duplicate_images';
-                        imageField.value = images;
-                        form.appendChild(imageField);
-                    }
-                }
-                
-                // Show image preview
-                showDuplicateImagePreview(duplicateData.images);
-            }
-        }
-    }
-    
-    // Function to show preview of duplicate images
-    function showDuplicateImagePreview(images) {
-        const previewContainer = document.getElementById('image-preview-container');
-        if (!previewContainer) return;
-        
-        console.log("showDuplicateImagePreview called with:", images);
-        
-        // Make sure images is treated as an array
-        if (!Array.isArray(images)) {
-            if (typeof images === 'string') {
-                // Try to parse if it's a JSON string
-                try {
-                    images = JSON.parse(images);
-                } catch (e) {
-                    // If parsing fails, wrap the single string in an array
-                    images = [images];
-                }
-            } else {
-                console.error("Invalid images data:", images);
-                return;
-            }
-        }
-        
-        previewContainer.innerHTML = '';
-        console.log(`Processing ${images.length} images for preview`);
-        
-        images.forEach((imageName, index) => {
-            console.log(`Processing image ${index}:`, imageName);
-            const preview = document.createElement('div');
-            preview.className = 'image-preview-item';
-            preview.innerHTML = `
-                <img src="/uploads/${imageName}" alt="Duplicate Image ${index + 1}" class="duplicate-image-preview">
-                <div class="image-controls">
-                    <span>Von Original übernommen</span>
-                    <button type="button" onclick="removeDuplicateImage('${imageName}', this)" class="remove-duplicate-image-button">Entfernen</button>
-                </div>
-            `;
-            previewContainer.appendChild(preview);
-        });
-    }
-    
-    // Function to remove a duplicate image
-    function removeDuplicateImage(imageName, button) {
-        // Remove the hidden input
-        const hiddenInputs = document.querySelectorAll('input[name="duplicate_images"]');
-        hiddenInputs.forEach(input => {
-            if (input.value === imageName) {
-                input.remove();
-            }
-        });
-        
-        // Remove the preview
-        const previewItem = button.closest('.image-preview-item');
-        if (previewItem) {
-            previewItem.remove();
+            console.log("Parsed duplicate images successfully.");
         }
     }
 </script>