Refactor MongoDB client imports and implement lazy loading for main items in UI

Web/ausleihung.py

@@ -25,7 +25,6 @@ Sammlungsstruktur:
    Unauthorized commercial use, SaaS hosting, or removal of branding is prohibited.
    For commercial licensing inquiries: https://github.com/AIIrondev
 '''
-from pymongo import MongoClient
 from bson.objectid import ObjectId
 import datetime
 import pytz
@@ -34,6 +33,7 @@ import os
 import json
 import shutil
 import settings as cfg
+from settings import MongoClient
 
 # Add this helper function after imports
 def ensure_timezone_aware(dt):

Web/items.py

@@ -26,10 +26,10 @@ Collection Structure:
    Unauthorized commercial use, SaaS hosting, or removal of branding is prohibited.
    For commercial licensing inquiries: https://github.com/AIIrondev
 '''
-from pymongo import MongoClient
 from bson.objectid import ObjectId
 import datetime
 import settings as cfg
+from settings import MongoClient
 
 
 LIBRARY_ITEM_TYPES = ('book', 'cd', 'dvd', 'media')

Web/requirements.txt

@@ -10,4 +10,5 @@ python-dateutil
 pytz
 requests
 reportlab
-python-barcode
+python-barcode
+openpyxl

Web/settings.py

@@ -12,6 +12,9 @@ defaults for the web application and helper modules.
 """
 import os
 import json
+from functools import lru_cache
+
+from pymongo import MongoClient as _PyMongoClient
 
 # Base directory of this Web package
 BASE_DIR = os.path.dirname(os.path.abspath(__file__))
@@ -173,3 +176,21 @@ if not os.path.isabs(BACKUP_FOLDER):
     BACKUP_FOLDER = os.path.join(PROJECT_ROOT, BACKUP_FOLDER)
 if not os.path.isabs(LOGS_FOLDER):
     LOGS_FOLDER = os.path.join(PROJECT_ROOT, LOGS_FOLDER)
+
+
+@lru_cache(maxsize=1)
+def _shared_mongo_client():
+    return _PyMongoClient(
+        MONGODB_HOST,
+        MONGODB_PORT,
+        maxPoolSize=10,
+        minPoolSize=0,
+        connectTimeoutMS=5000,
+        serverSelectionTimeoutMS=5000,
+        retryWrites=True,
+    )
+
+
+def MongoClient(*args, **kwargs):
+    """Return a shared MongoDB client configured from this settings module."""
+    return _shared_mongo_client()

Web/templates/admin_audit.html

@@ -5,6 +5,11 @@
   <h1>Audit Dashboard</h1>
   <p>Integritätsstatus der Audit-Chain und letzte Audit-Ereignisse (max. 200 Einträge).</p>
 
+  <div style="display:flex; gap:10px; flex-wrap:wrap; margin:10px 0 18px;">
+    <a class="btn btn-primary" href="{{ url_for('admin_audit_export', format='md') }}">Audit Review exportieren (Markdown)</a>
+    <a class="btn btn-outline-secondary" href="{{ url_for('admin_audit_export', format='json') }}">Audit Review exportieren (JSON)</a>
+  </div>
+
   <div style="display:grid; grid-template-columns:repeat(auto-fit,minmax(220px,1fr)); gap:12px; margin:16px 0 20px;">
     <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background:#fff;">
       <div style="font-size:0.85rem; color:#64748b;">Chain Status</div>

Web/templates/library_table.html

@@ -290,6 +290,20 @@
         color: #666;
     }
 
+    .library-load-row {
+        margin-top: 12px;
+        display: flex;
+        align-items: center;
+        justify-content: space-between;
+        gap: 12px;
+        flex-wrap: wrap;
+    }
+
+    .library-load-hint {
+        font-size: 0.9em;
+        color: #6b7280;
+    }
+
     /* Modal styles */
     .modal {
         display: none;
@@ -501,6 +515,10 @@
                 <!-- Items will be loaded here -->
             </tbody>
         </table>
+        <div id="loadMoreRow" class="library-load-row" style="display:none;">
+            <span id="loadInfo" class="library-load-hint"></span>
+            <button id="loadMoreBtn" class="button" type="button">Mehr laden</button>
+        </div>
     </div>
 
     <!-- Empty state -->
@@ -523,6 +541,24 @@
     // State
     let libraryItems = [];
     let filteredItems = [];
+    let visibleItems = [];
+    let currentSearchTerm = '';
+    let activeFilters = {
+        author: '',
+        isbn: '',
+        type: '',
+        status: ''
+    };
+    let pagingState = {
+        offset: 0,
+        total: 0,
+        hasMore: true,
+        loading: false
+    };
+    const API_PAGE_SIZE = 120;
+    const INITIAL_RENDER_COUNT = 120;
+    const RENDER_BATCH_COUNT = 120;
+    let renderedCount = INITIAL_RENDER_COUNT;
     let filterPanelOpen = false;
     let scannerInstance = null;
     let scannerRunning = false;
@@ -531,32 +567,124 @@
     let lastScanAt = 0;
     const canEditLibraryItems = (document.getElementById('libraryTableContainer')?.dataset.canEdit === '1');
 
-    // Load items
+    async function fetchLibraryPage(offset, limit) {
+        const response = await fetch(`/api/library_items?offset=${offset}&limit=${limit}`);
+        if (!response.ok) {
+            throw new Error('Failed to load library items');
+        }
+        return response.json();
+    }
+
+    // Load items progressively: first page immediately, rest in background
     async function loadLibraryItems() {
+        if (pagingState.loading) return;
+        pagingState.loading = true;
         try {
-            const response = await fetch('/api/library_items');
-            if (!response.ok) throw new Error('Failed to load library items');
-            libraryItems = await response.json();
-            displayItems(libraryItems);
+            const firstPage = await fetchLibraryPage(0, API_PAGE_SIZE);
+            libraryItems = firstPage.items || [];
+            pagingState.offset = (firstPage.offset || 0) + (firstPage.count || libraryItems.length);
+            pagingState.total = firstPage.total || libraryItems.length;
+            pagingState.hasMore = Boolean(firstPage.has_more);
+
+            applyFiltersAndSearch(true);
+
+            if (pagingState.hasMore) {
+                loadRemainingLibraryItemsInBackground();
+            }
         } catch (error) {
             console.error('Error loading library items:', error);
             document.getElementById('itemsTableBody').innerHTML = '<tr><td colspan="6" style="text-align:center; color:#999;">Fehler beim Laden der Bibliothekselemente.</td></tr>';
+        } finally {
+            pagingState.loading = false;
         }
     }
 
-    // Display items in table
-    function displayItems(items) {
+    async function loadRemainingLibraryItemsInBackground() {
+        while (pagingState.hasMore) {
+            try {
+                const page = await fetchLibraryPage(pagingState.offset, API_PAGE_SIZE);
+                const nextItems = page.items || [];
+                if (nextItems.length === 0) {
+                    pagingState.hasMore = false;
+                    break;
+                }
+
+                libraryItems = libraryItems.concat(nextItems);
+                pagingState.offset = (page.offset || pagingState.offset) + (page.count || nextItems.length);
+                pagingState.total = page.total || pagingState.total;
+                pagingState.hasMore = Boolean(page.has_more);
+
+                // Keep the current view reactive while avoiding a full rerender burst.
+                applyFiltersAndSearch(false);
+
+                if ('requestIdleCallback' in window) {
+                    await new Promise(resolve => requestIdleCallback(() => resolve(), { timeout: 250 }));
+                } else {
+                    await new Promise(resolve => setTimeout(resolve, 0));
+                }
+            } catch (error) {
+                console.error('Error loading additional library items:', error);
+                break;
+            }
+        }
+    }
+
+    function filterItems(items) {
+        const author = activeFilters.author;
+        const isbn = activeFilters.isbn;
+        const type = activeFilters.type;
+        const status = activeFilters.status;
+
+        return items.filter(item => {
+            const authorMatch = !author || (item.Autor || item.Author || '').toLowerCase().includes(author);
+            const isbnMatch = !isbn || (item.ISBN || item.Code_4 || item.Code4 || '').toLowerCase().includes(isbn);
+            const typeMatch = !type || (item.ItemType || 'book') === type;
+            const statusKey = item.LibraryDisplayStatus || (item.Verfuegbar === false ? 'borrowed' : 'available');
+            const statusMatch = !status || statusKey === status;
+            return authorMatch && isbnMatch && typeMatch && statusMatch;
+        });
+    }
+
+    function applySearch(items) {
+        if (!currentSearchTerm) return items;
+        return items.filter(item =>
+            (item.Name || '').toLowerCase().includes(currentSearchTerm) ||
+            (item.Autor || item.Author || '').toLowerCase().includes(currentSearchTerm) ||
+            (item.ISBN || item.Code_4 || item.Code4 || '').toLowerCase().includes(currentSearchTerm)
+        );
+    }
+
+    function applyFiltersAndSearch(resetRenderCount) {
+        const filteredByPanel = filterItems(libraryItems);
+        filteredItems = applySearch(filteredByPanel);
+        if (resetRenderCount) {
+            renderedCount = Math.min(INITIAL_RENDER_COUNT, filteredItems.length);
+        } else {
+            renderedCount = Math.min(Math.max(renderedCount, INITIAL_RENDER_COUNT), filteredItems.length || INITIAL_RENDER_COUNT);
+        }
+        visibleItems = filteredItems;
+        renderItems();
+    }
+
+    // Display current view with incremental rendering
+    function renderItems() {
         const tbody = document.getElementById('itemsTableBody');
         const emptyState = document.getElementById('emptyState');
+        const loadMoreRow = document.getElementById('loadMoreRow');
+        const loadInfo = document.getElementById('loadInfo');
+        const loadMoreBtn = document.getElementById('loadMoreBtn');
 
-        if (items.length === 0) {
+        if (visibleItems.length === 0) {
             tbody.innerHTML = '';
             emptyState.style.display = 'block';
+            loadMoreRow.style.display = 'none';
             return;
         }
 
         emptyState.style.display = 'none';
-        tbody.innerHTML = items.map(item => `
+        const rowsToRender = visibleItems.slice(0, renderedCount);
+
+        tbody.innerHTML = rowsToRender.map(item => `
             ${(() => {
                 const statusKey = item.LibraryDisplayStatus || (item.Verfuegbar === false ? 'borrowed' : 'available');
                 const statusClass = statusKey === 'damaged' ? 'status-damaged' : (statusKey === 'borrowed' ? 'status-borrowed' : 'status-available');
@@ -567,7 +695,7 @@
             <tr>
                 <td class="table-title">${escapeHtml(item.Name || 'Untitled')}</td>
                 <td>${escapeHtml(item.Autor || item.Author || '-')}</td>
-                <td>${escapeHtml(item.ISBN || item.Code4 || '-')}</td>
+                <td>${escapeHtml(item.ISBN || item.Code_4 || item.Code4 || '-')}</td>
                 <td>${getItemTypeLabel(item.ItemType || 'book')}</td>
                 <td>
                     <span class="table-status ${statusClass}">
@@ -585,6 +713,18 @@
                 `;
             })()}
         `).join('');
+
+        const canLoadMoreRows = renderedCount < visibleItems.length;
+        if (canLoadMoreRows) {
+            loadMoreRow.style.display = 'flex';
+            loadMoreBtn.style.display = 'inline-block';
+            loadInfo.textContent = `${renderedCount} von ${visibleItems.length} angezeigt`;
+        } else {
+            const backgroundHint = pagingState.hasMore ? `Lade weitere Medien im Hintergrund (${libraryItems.length}/${pagingState.total || '?'})...` : `${visibleItems.length} Treffer`;
+            loadMoreRow.style.display = 'flex';
+            loadMoreBtn.style.display = 'none';
+            loadInfo.textContent = backgroundHint;
+        }
     }
 
     // Filter toggle
@@ -598,21 +738,11 @@
 
     // Apply filters
     document.getElementById('applyFilterBtn').addEventListener('click', () => {
-        const author = document.getElementById('filterAuthor').value.toLowerCase();
-        const isbn = document.getElementById('filterISBN').value.toLowerCase();
-        const type = document.getElementById('filterType').value;
-        const status = document.getElementById('filterStatus').value;
-
-        filteredItems = libraryItems.filter(item => {
-            const authorMatch = !author || (item.Autor || item.Author || '').toLowerCase().includes(author);
-            const isbnMatch = !isbn || (item.ISBN || item.Code4 || '').toLowerCase().includes(isbn);
-            const typeMatch = !type || (item.ItemType || 'book') === type;
-            const statusKey = item.LibraryDisplayStatus || (item.Verfuegbar === false ? 'borrowed' : 'available');
-            const statusMatch = !status || statusKey === status;
-            return authorMatch && isbnMatch && typeMatch && statusMatch;
-        });
-
-        displayItems(filteredItems);
+        activeFilters.author = document.getElementById('filterAuthor').value.toLowerCase();
+        activeFilters.isbn = document.getElementById('filterISBN').value.toLowerCase();
+        activeFilters.type = document.getElementById('filterType').value;
+        activeFilters.status = document.getElementById('filterStatus').value;
+        applyFiltersAndSearch(true);
     });
 
     // Clear filters
@@ -621,19 +751,19 @@
         document.getElementById('filterISBN').value = '';
         document.getElementById('filterType').value = '';
         document.getElementById('filterStatus').value = '';
-        displayItems(libraryItems);
+        activeFilters = { author: '', isbn: '', type: '', status: '' };
+        applyFiltersAndSearch(true);
     });
 
     // Search input
     document.getElementById('librarySearch').addEventListener('input', (e) => {
-        const searchTerm = e.target.value.toLowerCase();
-        const toSearch = filteredItems.length > 0 ? filteredItems : libraryItems;
-        const results = toSearch.filter(item =>
-            (item.Name || '').toLowerCase().includes(searchTerm) ||
-            (item.Autor || item.Author || '').toLowerCase().includes(searchTerm) ||
-            (item.ISBN || item.Code4 || '').toLowerCase().includes(searchTerm)
-        );
-        displayItems(results);
+        currentSearchTerm = (e.target.value || '').toLowerCase();
+        applyFiltersAndSearch(true);
+    });
+
+    document.getElementById('loadMoreBtn').addEventListener('click', () => {
+        renderedCount = Math.min(renderedCount + RENDER_BATCH_COUNT, visibleItems.length);
+        renderItems();
     });
 
     // Helper functions

Web/templates/main.html

@@ -724,8 +724,15 @@
     // Add this line to define allItems globally
     let allItems = [];
 
-    function loadItems() {
-        fetch("{{ url_for('get_items') }}")
+    const MAIN_ITEMS_PAGE_SIZE = 120;
+    let mainItemsNextOffset = 0;
+    let mainItemsHasMore = false;
+    let mainItemsLoadingMore = false;
+    let mainItemsObserver = null;
+    let mainItemsSentinel = null;
+
+    function loadItems(offset = 0, append = false) {
+        return fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ITEMS_PAGE_SIZE}`)
             .then(response => response.json())
             .then(data => {
                 const itemsContainer = document.querySelector('#items-container');
@@ -735,27 +742,39 @@
                 const filter3Values = new Set();
                 
                 // Store all items data globally for filter rebuilding
-                allItems = data.items || [];
+                const pageItems = data.items || [];
+                allItems = append ? allItems.concat(pageItems) : pageItems;
                 
                 // Clear the container first
-                itemsContainer.innerHTML = '';
+                if (!append) {
+                    itemsContainer.innerHTML = '';
+                }
                 
-                if (!data.items || data.items.length === 0) {
+                if (!append && (!pageItems || pageItems.length === 0)) {
                     itemsContainer.innerHTML = '<div class="no-items-message">Keine Objekte gefunden</div>';
                     return;
                 }
 
                 // Sort items by name in ascending order (A-Z)
-                data.items.sort((a, b) => {
+                pageItems.sort((a, b) => {
                     const nameA = a.Name ? a.Name.toLowerCase() : '';
                     const nameB = b.Name ? b.Name.toLowerCase() : '';
                     return nameA.localeCompare(nameB); // Ascending order
                 });
+
+                allItems.forEach(itemForFilters => {
+                    const f1 = Array.isArray(itemForFilters.Filter) ? itemForFilters.Filter : (itemForFilters.Filter ? [itemForFilters.Filter] : []);
+                    const f2 = Array.isArray(itemForFilters.Filter2) ? itemForFilters.Filter2 : (itemForFilters.Filter2 ? [itemForFilters.Filter2] : []);
+                    const f3 = Array.isArray(itemForFilters.Filter3) ? itemForFilters.Filter3 : (itemForFilters.Filter3 ? [itemForFilters.Filter3] : []);
+                    f1.forEach(value => { if (value && typeof value === 'string' && value.trim() !== '') filter1Values.add(value); });
+                    f2.forEach(value => { if (value && typeof value === 'string' && value.trim() !== '') filter2Values.add(value); });
+                    f3.forEach(value => { if (value && typeof value === 'string' && value.trim() !== '') filter3Values.add(value); });
+                });
                 
                 const favoriteIds = new Set(data.favorites || []);
                 window.currentFavorites = favoriteIds;
                 try { sessionStorage.setItem('favoritesCache', JSON.stringify(Array.from(favoriteIds))); } catch(e){}
-                data.items.forEach(item => {
+                pageItems.forEach(item => {
                     try {
                         const card = document.createElement('div');
                         card.classList.add('item-card');
@@ -995,8 +1014,10 @@
                 populateFilterOptions('filter2-options', [...filter2Values].sort(), 2);
                 populateFilterOptions('filter3-options', [...filter3Values].sort(), 3);
                 
-                // Start display from leftmost position (first card, which is now Z)
-                itemsContainer.scrollLeft = 0;
+                // Start display from leftmost position on full reload only.
+                if (!append) {
+                    itemsContainer.scrollLeft = 0;
+                }
                 
                 // Apply filters
                 applyFilters();
@@ -1011,15 +1032,78 @@
                 if (activeFilters.filter1.length > 0 || activeFilters.filter2.length > 0) {
                     rebuildFilter3Options();
                 }
+
+                mainItemsNextOffset = (data.offset || offset) + (data.count || pageItems.length);
+                mainItemsHasMore = Boolean(data.has_more);
+                setupMainItemsLazyLoading();
             })
             .catch(error => {
                 console.error('Error fetching items:', error);
+                if (append) {
+                    return;
+                }
                 const itemsContainer = document.querySelector('#items-container');
                 itemsContainer.innerHTML = 
                     '<div class="error-message">Fehler beim Laden der Objekte. Bitte versuchen Sie es später erneut.</div>';
             });
     }
 
+    function ensureMainItemsSentinel() {
+        const itemsContainer = document.querySelector('#items-container');
+        if (!itemsContainer) return null;
+
+        if (!mainItemsSentinel) {
+            mainItemsSentinel = document.createElement('div');
+            mainItemsSentinel.id = 'main-items-sentinel';
+            mainItemsSentinel.style.flex = '0 0 1px';
+            mainItemsSentinel.style.width = '1px';
+            mainItemsSentinel.style.minWidth = '1px';
+            mainItemsSentinel.style.height = '1px';
+            mainItemsSentinel.style.pointerEvents = 'none';
+        }
+
+        if (!mainItemsSentinel.parentNode) {
+            itemsContainer.appendChild(mainItemsSentinel);
+        } else {
+            itemsContainer.appendChild(mainItemsSentinel);
+        }
+
+        return itemsContainer;
+    }
+
+    function setupMainItemsLazyLoading() {
+        const itemsContainer = ensureMainItemsSentinel();
+        if (!itemsContainer) return;
+
+        if (mainItemsObserver) {
+            mainItemsObserver.disconnect();
+            mainItemsObserver = null;
+        }
+
+        if (!mainItemsHasMore) return;
+
+        mainItemsObserver = new IntersectionObserver(entries => {
+            if (!entries.some(entry => entry.isIntersecting)) {
+                return;
+            }
+
+            if (mainItemsLoadingMore || !mainItemsHasMore) {
+                return;
+            }
+
+            mainItemsLoadingMore = true;
+            loadItems(mainItemsNextOffset, true).finally(() => {
+                mainItemsLoadingMore = false;
+            });
+        }, {
+            root: itemsContainer,
+            threshold: 0.15,
+            rootMargin: '0px 220px 0px 0px'
+        });
+
+        mainItemsObserver.observe(mainItemsSentinel);
+    }
+
     function searchByCode() {
         const searchInput = document.getElementById('code-search');
         const rawSearchTerm = searchInput.value;

Web/templates/main_admin.html

@@ -26,6 +26,106 @@
         font-weight: 600;
     }
 
+    .bulk-delete-inline-wrap {
+        display: inline-flex;
+    }
+
+    .bulk-delete-drawer-toggle {
+        position: static;
+        transform: none;
+        z-index: 2;
+    }
+
+    .bulk-delete-drawer-toggle .drawer-icon {
+        display: inline-block;
+        margin-right: 4px;
+    }
+
+    .bulk-delete-drawer-toggle:hover {
+        box-shadow: 0 10px 20px rgba(13, 110, 253, 0.3);
+    }
+
+    .bulk-delete-drawer-toggle:active {
+        transform: scale(0.98);
+    }
+
+    .bulk-delete-drawer {
+        display: none;
+        width: 100%;
+        max-width: 980px;
+        margin: 0 auto 18px;
+        border: 1px solid #dbe3ee;
+        background: #ffffff;
+        border-radius: 10px;
+        padding: 14px;
+        box-shadow: 0 8px 18px rgba(15, 23, 42, 0.08);
+    }
+
+    .bulk-delete-drawer.open {
+        display: flex;
+        flex-wrap: wrap;
+        justify-content: space-between;
+        gap: 14px;
+    }
+
+    .bulk-delete-content {
+        flex: 1 1 380px;
+    }
+
+    .bulk-delete-drawer strong {
+        display: block;
+        margin-bottom: 2px;
+    }
+
+    .bulk-delete-summary {
+        color: #334155;
+        font-size: 0.92rem;
+        margin-top: 4px;
+    }
+
+    .bulk-delete-drawer small {
+        color: #64748b;
+        display: block;
+        margin-top: 2px;
+        line-height: 1.35;
+    }
+
+    .bulk-delete-actions {
+        display: flex;
+        flex-wrap: wrap;
+        gap: 8px;
+        margin-top: 4px;
+        align-items: center;
+        flex: 0 1 auto;
+    }
+
+    .bulk-delete-actions button {
+        border: 1px solid #dbe3ee;
+        border-radius: 8px;
+        padding: 9px 12px;
+        cursor: pointer;
+        background: #f8fafc;
+        color: #1e293b;
+        font-weight: 600;
+        text-align: center;
+    }
+
+    .bulk-delete-actions button:hover {
+        background: #eef4ff;
+        border-color: #bfdbfe;
+    }
+
+    .bulk-delete-actions .danger {
+        background: #dc3545;
+        color: #fff;
+        border-color: #c82333;
+    }
+
+    .bulk-delete-actions .danger:hover {
+        background: #c82333;
+        border-color: #b21f2d;
+    }
+
     /* Filter styles */
     .filter-container {
         display: flex;
@@ -237,6 +337,12 @@
         position: relative;
     }
 
+    .item-card.bulk-selected {
+        border-color: #dc3545;
+        box-shadow: 0 0 0 2px rgba(220, 53, 69, 0.18), 0 0 10px rgba(0, 0, 0, 0.1);
+        background: #fffdfd;
+    }
+
     .item-card:hover {
         transform: translateY(-5px);
         box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
@@ -257,6 +363,45 @@
         margin: 10px 0;
     }
 
+    .bulk-delete-row {
+        display: flex;
+        justify-content: flex-start;
+        align-items: center;
+        margin-bottom: 8px;
+        gap: 8px;
+    }
+
+    .bulk-delete-toggle {
+        display: inline-flex;
+        align-items: center;
+        gap: 6px;
+        font-size: 0.9rem;
+        color: #475569;
+        cursor: pointer;
+        user-select: none;
+    }
+
+    .bulk-delete-toggle input {
+        width: 16px;
+        height: 16px;
+        accent-color: #dc3545;
+        cursor: pointer;
+    }
+
+    @media (max-width: 768px) {
+        .bulk-delete-drawer.open {
+            flex-direction: column;
+        }
+
+        .bulk-delete-actions {
+            width: 100%;
+        }
+
+        .bulk-delete-actions button {
+            width: 100%;
+        }
+    }
+
     .item-card .item-image {
         width: 100%;
         height: auto;
@@ -2109,9 +2254,26 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 <button id="toggle-favorites-view" class="view-toggle-btn" title="Nur Merkliste anzeigen">
                     <span id="favorites-view-icon">🔖</span>
                 </button>
+                <div class="bulk-delete-inline-wrap">
+                    <button type="button" id="bulk-delete-drawer-toggle" class="view-toggle-btn bulk-delete-drawer-toggle" aria-expanded="false" title="Massenlöschung" onclick="toggleBulkDeleteDrawer()">
+                        <span class="drawer-icon">⚙</span>
+                    </button>
+                </div>
             </div>
         </h1>
         <div id="items-indicator" class="items-indicator">Objekte im System: 0</div>
+        <div id="bulk-delete-drawer" class="bulk-delete-drawer" aria-hidden="true">
+            <div class="bulk-delete-content">
+                <strong>Massenlöschung nach Kriterien</strong>
+                <div class="bulk-delete-summary" id="bulk-delete-summary">0 Elemente ausgewählt</div>
+                <small>Filter zuerst setzen, dann alle sichtbaren Elemente markieren oder einzelne Karten per Checkbox auswählen.</small>
+            </div>
+            <div class="bulk-delete-actions">
+                <button type="button" onclick="selectVisibleItems()">Alle sichtbaren auswählen</button>
+                <button type="button" onclick="clearBulkSelection()">Auswahl leeren</button>
+                <button type="button" id="bulk-delete-button" class="danger" onclick="deleteSelectedItems()" disabled>Auswahl löschen</button>
+            </div>
+        </div>
         <div class="filter-container">
             <div class="filter-group">
                 <div class="filter-header">
@@ -2492,6 +2654,8 @@ document.addEventListener('DOMContentLoaded', ()=>{
     let descSearchIds = null; // Set of matching IDs or null when disabled
     let currentUsername = '';
     let allItems = []; // Cache for all items
+    let bulkDeleteSelection = new Set();
+    let bulkDeleteDrawerOpen = false;
     const studentCardsModuleEnabled = {{ 'true' if student_cards_module_enabled else 'false' }};
     const studentDefaultBorrowDays = {{ student_default_borrow_days|default(14) }};
     const studentMaxBorrowDays = {{ student_max_borrow_days|default(365) }};
@@ -2822,6 +2986,134 @@ document.addEventListener('DOMContentLoaded', ()=>{
             filter3: []
         };
     }
+
+    function updateBulkDeleteSummary() {
+        const summary = document.getElementById('bulk-delete-summary');
+        const button = document.getElementById('bulk-delete-button');
+        const count = bulkDeleteSelection.size;
+
+        if (summary) {
+            summary.textContent = `${count} ${count === 1 ? 'Element' : 'Elemente'} ausgewählt`;
+        }
+        if (button) {
+            button.disabled = count === 0;
+            button.textContent = count === 0 ? 'Auswahl löschen' : `Auswahl löschen (${count})`;
+        }
+    }
+
+    function setBulkDeleteDrawer(open) {
+        bulkDeleteDrawerOpen = Boolean(open);
+        const drawer = document.getElementById('bulk-delete-drawer');
+        const toggle = document.getElementById('bulk-delete-drawer-toggle');
+        if (drawer) {
+            drawer.classList.toggle('open', bulkDeleteDrawerOpen);
+            drawer.setAttribute('aria-hidden', bulkDeleteDrawerOpen ? 'false' : 'true');
+        }
+        if (toggle) {
+            toggle.setAttribute('aria-expanded', bulkDeleteDrawerOpen ? 'true' : 'false');
+            toggle.innerHTML = bulkDeleteDrawerOpen ? '<span class="drawer-icon">✕</span>' : '<span class="drawer-icon">⚙</span>';
+            toggle.title = bulkDeleteDrawerOpen ? 'Massenlöschung schließen' : 'Massenlöschung öffnen';
+        }
+    }
+
+    function toggleBulkDeleteDrawer() {
+        setBulkDeleteDrawer(!bulkDeleteDrawerOpen);
+    }
+
+    function setBulkDeleteSelection(itemId, checked) {
+        const normalizedId = String(itemId || '').trim();
+        if (!normalizedId) {
+            return;
+        }
+
+        if (checked) {
+            bulkDeleteSelection.add(normalizedId);
+        } else {
+            bulkDeleteSelection.delete(normalizedId);
+        }
+
+        document.querySelectorAll(`.item-card[data-item-id='${normalizedId}']`).forEach(card => {
+            card.classList.toggle('bulk-selected', checked);
+            const checkbox = card.querySelector('.bulk-delete-checkbox');
+            if (checkbox && checkbox.checked !== checked) {
+                checkbox.checked = checked;
+            }
+        });
+
+        updateBulkDeleteSummary();
+    }
+
+    function selectVisibleItems() {
+        document.querySelectorAll('.item-card').forEach(card => {
+            if (card.style.display === 'none') {
+                return;
+            }
+            const itemId = String(card.dataset.itemId || '').trim();
+            if (!itemId) {
+                return;
+            }
+            bulkDeleteSelection.add(itemId);
+            card.classList.add('bulk-selected');
+            const checkbox = card.querySelector('.bulk-delete-checkbox');
+            if (checkbox) {
+                checkbox.checked = true;
+            }
+        });
+
+        updateBulkDeleteSummary();
+    }
+
+    function clearBulkSelection() {
+        bulkDeleteSelection.clear();
+        document.querySelectorAll('.item-card.bulk-selected').forEach(card => {
+            card.classList.remove('bulk-selected');
+            const checkbox = card.querySelector('.bulk-delete-checkbox');
+            if (checkbox) {
+                checkbox.checked = false;
+            }
+        });
+
+        updateBulkDeleteSummary();
+    }
+
+    document.addEventListener('keydown', function(event) {
+        if (event.key === 'Escape' && bulkDeleteDrawerOpen) {
+            setBulkDeleteDrawer(false);
+        }
+    });
+
+    function deleteSelectedItems() {
+        const selectedIds = [...bulkDeleteSelection];
+        if (selectedIds.length === 0) {
+            alert('Bitte zuerst mindestens ein Element auswählen.');
+            return;
+        }
+
+        if (!confirm(`Wirklich ${selectedIds.length} ausgewählte Elemente revisionssicher deaktivieren?`)) {
+            return;
+        }
+
+        fetch('{{ url_for('bulk_delete_items') }}', {
+            method: 'POST',
+            headers: {
+                'Content-Type': 'application/json',
+                'Accept': 'application/json'
+            },
+            body: JSON.stringify({ item_ids: selectedIds })
+        })
+        .then(async response => {
+            const data = await response.json().catch(() => ({}));
+            if (!response.ok || !data.success) {
+                throw new Error(data.message || 'Fehler beim Sammellöschen.');
+            }
+            clearBulkSelection();
+            alert(data.message || 'Auswahl gelöscht.');
+            loadItems();
+        })
+        .catch(error => {
+            alert(error.message || 'Fehler beim Sammellöschen.');
+        });
+    }
     
     // Load predefined filter values for dropdowns
     function loadPredefinedFilterValues(filterNumber) {
@@ -2963,8 +3255,15 @@ document.addEventListener('DOMContentLoaded', ()=>{
     });
 
     // Function to load items from server
-    function loadItems() {
-        fetch("{{ url_for('get_items') }}")
+    const MAIN_ADMIN_ITEMS_PAGE_SIZE = 120;
+    let mainAdminItemsNextOffset = 0;
+    let mainAdminItemsHasMore = false;
+    let mainAdminItemsLoadingMore = false;
+    let mainAdminItemsObserver = null;
+    let mainAdminItemsSentinel = null;
+
+    function loadItems(offset = 0, append = false) {
+        return fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ADMIN_ITEMS_PAGE_SIZE}`)
             .then(response => response.json())
             .then(data => {
                 const itemsContainer = document.querySelector('#items-container');
@@ -2974,9 +3273,12 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 const filter1Values = new Set();
                 const filter2Values = new Set();
                 const filter3Values = new Set();
-                allItems = data.items || [];
-                itemsContainer.innerHTML = '';
-                if (!data.items || data.items.length === 0) {
+                const pageItems = data.items || [];
+                allItems = append ? allItems.concat(pageItems) : pageItems;
+                if (!append) {
+                    itemsContainer.innerHTML = '';
+                }
+                if (!append && (!pageItems || pageItems.length === 0)) {
                     itemsContainer.innerHTML = `
                         <div class="no-items-message">
                             <div>Keine Objekte gefunden</div>
@@ -2989,15 +3291,27 @@ document.addEventListener('DOMContentLoaded', ()=>{
                     return;
                 }
                 if (itemsIndicator) {
-                    itemsIndicator.textContent = `Objekte im System: ${data.items.length}`;
+                    const shownCount = allItems.length;
+                    const totalCount = Number(data.total || shownCount);
+                    itemsIndicator.textContent = `Objekte im System: ${shownCount}${data.has_more ? ` / ${totalCount} (lädt...)` : ''}`;
                 }
-                data.items.sort((a, b) => {
+                pageItems.sort((a, b) => {
                     const nameA = a.Name ? a.Name.toLowerCase() : '';
                     const nameB = a.Name ? a.Name.toLowerCase() : '';
                     return nameA.localeCompare(nameB);
                 });
+
+                allItems.forEach(itemForFilters => {
+                    const f1 = Array.isArray(itemForFilters.Filter) ? itemForFilters.Filter : (itemForFilters.Filter ? [itemForFilters.Filter] : []);
+                    const f2 = Array.isArray(itemForFilters.Filter2) ? itemForFilters.Filter2 : (itemForFilters.Filter2 ? [itemForFilters.Filter2] : []);
+                    const f3 = Array.isArray(itemForFilters.Filter3) ? itemForFilters.Filter3 : (itemForFilters.Filter3 ? [itemForFilters.Filter3] : []);
+                    f1.forEach(value => { if (value && typeof value === 'string' && value.trim() !== '') filter1Values.add(value); });
+                    f2.forEach(value => { if (value && typeof value === 'string' && value.trim() !== '') filter2Values.add(value); });
+                    f3.forEach(value => { if (value && typeof value === 'string' && value.trim() !== '') filter3Values.add(value); });
+                });
+
                 const favoriteIds = new Set(data.favorites || []);
-                data.items.forEach(item => {
+                pageItems.forEach(item => {
                     try {
                         const card = document.createElement('div');
                         card.classList.add('item-card');
@@ -3148,6 +3462,12 @@ document.addEventListener('DOMContentLoaded', ()=>{
                                 ${appointmentBadge}
                             </div>
                             <div class="actions">
+                                <div class="bulk-delete-row">
+                                    <label class="bulk-delete-toggle">
+                                        <input type="checkbox" class="bulk-delete-checkbox" data-item-id="${item._id}" ${bulkDeleteSelection.has(String(item._id)) ? 'checked' : ''} onchange="setBulkDeleteSelection('${item._id}', this.checked)">
+                                        Für Löschung markieren
+                                    </label>
+                                </div>
                                 ${isAvailableForBorrow && !item.BlockedNow ? 
                                     `<form method="POST" action="{{ url_for('ausleihen', id='') }}${item._id}">
                                         ${isGroupedItem ? `
@@ -3223,8 +3543,11 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 populateFilterOptions('filter2-options', [...filter2Values].sort(), 2);
                 populateFilterOptions('filter3-options', [...filter3Values].sort(), 3);
                 
-                itemsContainer.scrollLeft = 0;
+                if (!append) {
+                    itemsContainer.scrollLeft = 0;
+                }
                 applyFilters();
+                updateBulkDeleteSummary();
                 
                 // Setup proper image display for all cards
                 setupCardImagesDisplay();
@@ -3237,9 +3560,16 @@ document.addEventListener('DOMContentLoaded', ()=>{
                     rebuildFilter3Options();
                 }
                 /* favorites render count removed */
+
+                mainAdminItemsNextOffset = (data.offset || offset) + (data.count || pageItems.length);
+                mainAdminItemsHasMore = Boolean(data.has_more);
+                setupMainAdminItemsLazyLoading();
             })
             .catch(error => {
                 console.error('Error fetching items:', error);
+                if (append) {
+                    return;
+                }
                 const itemsContainer = document.querySelector('#items-container');
                 const itemsIndicator = document.getElementById('items-indicator');
                 itemsContainer.innerHTML = 
@@ -3250,6 +3580,57 @@ document.addEventListener('DOMContentLoaded', ()=>{
             });
     }
 
+    function ensureMainAdminItemsSentinel() {
+        const itemsContainer = document.querySelector('#items-container');
+        if (!itemsContainer) return null;
+
+        if (!mainAdminItemsSentinel) {
+            mainAdminItemsSentinel = document.createElement('div');
+            mainAdminItemsSentinel.id = 'main-admin-items-sentinel';
+            mainAdminItemsSentinel.style.flex = '0 0 1px';
+            mainAdminItemsSentinel.style.width = '1px';
+            mainAdminItemsSentinel.style.minWidth = '1px';
+            mainAdminItemsSentinel.style.height = '1px';
+            mainAdminItemsSentinel.style.pointerEvents = 'none';
+        }
+
+        itemsContainer.appendChild(mainAdminItemsSentinel);
+        return itemsContainer;
+    }
+
+    function setupMainAdminItemsLazyLoading() {
+        const itemsContainer = ensureMainAdminItemsSentinel();
+        if (!itemsContainer) return;
+
+        if (mainAdminItemsObserver) {
+            mainAdminItemsObserver.disconnect();
+            mainAdminItemsObserver = null;
+        }
+
+        if (!mainAdminItemsHasMore) return;
+
+        mainAdminItemsObserver = new IntersectionObserver(entries => {
+            if (!entries.some(entry => entry.isIntersecting)) {
+                return;
+            }
+
+            if (mainAdminItemsLoadingMore || !mainAdminItemsHasMore) {
+                return;
+            }
+
+            mainAdminItemsLoadingMore = true;
+            loadItems(mainAdminItemsNextOffset, true).finally(() => {
+                mainAdminItemsLoadingMore = false;
+            });
+        }, {
+            root: itemsContainer,
+            threshold: 0.15,
+            rootMargin: '0px 220px 0px 0px'
+        });
+
+        mainAdminItemsObserver.observe(mainAdminItemsSentinel);
+    }
+
     function searchByCode() {
         const searchInput = document.getElementById('code-search');
         const rawSearchTerm = searchInput.value;

Web/templates/upload_admin.html

@@ -710,6 +710,28 @@
 
 <div class="upload-container">
     <a href="{{ url_for(back_target|default('home_admin')) }}" class="nav-back-button">← Zurück zur Artikelübersicht</a>
+
+    {% if show_library_features %}
+    <div style="border:1px solid #dbe4ee; border-radius:8px; padding:14px; margin-bottom:16px; background:#f8fbff;">
+        <h3 style="margin:0 0 8px 0;">Excel-Import Bibliothek (Mehrere Bücher)</h3>
+        <p style="margin:0 0 10px 0; color:#555;">Laden Sie eine <strong>.xlsx</strong>-Datei hoch. Spalten werden automatisch erkannt (z.B. Name, Ort, Beschreibung, ISBN, Code, Anzahl). Für den Bibliotheksimport ist eine gültige ISBN je Zeile erforderlich.</p>
+        <form method="POST" action="{{ url_for('upload_library_excel') }}" enctype="multipart/form-data" style="display:flex; gap:10px; flex-wrap:wrap; align-items:center;">
+            <input type="file" name="library_excel" accept=".xlsx" required>
+            <button type="submit" class="btn btn-secondary" name="excel_action" value="validate">Nur validieren</button>
+            <button type="submit" class="btn btn-primary" name="excel_action" value="import">Bibliothek importieren</button>
+        </form>
+    </div>
+    {% else %}
+    <div style="border:1px solid #dbe4ee; border-radius:8px; padding:14px; margin-bottom:16px; background:#f8fbff;">
+        <h3 style="margin:0 0 8px 0;">Excel-Import Inventar (Mehrere Artikel)</h3>
+        <p style="margin:0 0 10px 0; color:#555;">Laden Sie eine <strong>.xlsx</strong>-Datei hoch. Spalten werden automatisch erkannt (z.B. Name, Ort, Beschreibung, Filter1/2/3, Kosten, Jahr, Code, Anzahl).</p>
+        <form method="POST" action="{{ url_for('upload_inventory_excel') }}" enctype="multipart/form-data" style="display:flex; gap:10px; flex-wrap:wrap; align-items:center;">
+            <input type="file" name="inventory_excel" accept=".xlsx" required>
+            <button type="submit" class="btn btn-secondary" name="excel_action" value="validate">Nur validieren</button>
+            <button type="submit" class="btn btn-primary" name="excel_action" value="import">Inventar importieren</button>
+        </form>
+    </div>
+    {% endif %}
     
     <div class="upload-form">
         <h1>{{ page_title|default('Artikel hochladen') }}</h1>

Web/user.py

@@ -10,10 +10,10 @@ Provides methods for creating, validating, and retrieving user information.
    Unauthorized commercial use, SaaS hosting, or removal of branding is prohibited.
    For commercial licensing inquiries: https://github.com/AIIrondev
 '''
-from pymongo import MongoClient
 import hashlib
 from bson.objectid import ObjectId
 import settings as cfg
+from settings import MongoClient
 
 
 def normalize_student_card_id(card_id):

requirements.txt

@@ -9,4 +9,5 @@ python-dateutil
 pytz
 requests
 reportlab
-python-barcode
+python-barcode
+openpyxl