Implement light mode for item loading to optimize initial data fetch

Web/app.py

@@ -33,7 +33,6 @@ import ausleihung as au
 import audit_log as al
 import datetime
 from apscheduler.schedulers.background import BackgroundScheduler
-from pymongo import MongoClient
 from bson.objectid import ObjectId
 from urllib.parse import urlparse, urlunparse
 import requests
@@ -59,6 +58,7 @@ import subprocess
 # Set base directory and centralized settings
 BASE_DIR = os.path.dirname(os.path.abspath(__file__))
 import settings as cfg
+from settings import MongoClient
 
 
 app = Flask(__name__, static_folder='static')  # Correctly set static folder
@@ -2950,6 +2950,7 @@ def get_items():
         available_only = str(request.args.get('available_only', '')).strip().lower() in ('1', 'true', 'yes', 'on')
         offset_raw = request.args.get('offset')
         limit_raw = request.args.get('limit')
+        light_mode_param = str(request.args.get('light_mode', '')).strip().lower()
         pagination_requested = offset_raw is not None or limit_raw is not None
 
         if pagination_requested:
@@ -2966,6 +2967,15 @@ def get_items():
             offset = 0
             limit = None
 
+        # Light mode: minimal fields for faster initial load (auto-enabled on offset=0 unless explicitly disabled)
+        # Can be manually controlled via ?light_mode=true/false parameter
+        if light_mode_param in ('1', 'true', 'yes', 'on'):
+            light_mode = True
+        elif light_mode_param in ('0', 'false', 'no', 'off'):
+            light_mode = False
+        else:
+            light_mode = (offset == 0)  # Auto-enable light mode for first page
+
         client = MongoClient(MONGODB_HOST, MONGODB_PORT)
         db = client[MONGODB_DB]
         items_col = db['items']
@@ -2977,18 +2987,98 @@ def get_items():
 
         total_count = items_col.count_documents(base_query)
 
-        items_cur = items_col.find(base_query).sort([('Name', 1), ('_id', 1)])
+        # Light projection: essentials only for fast initial render
+        light_projection = {
+            'Name': 1,
+            'Code_4': 1,
+            'Images': 1,
+            'ThumbnailInfo': 1,
+            'Verfuegbar': 1,
+            'Filter': 1,
+            'Filter2': 1,
+            'Filter3': 1,
+            'Ort': 1,
+            'User': 1,
+            'ItemType': 1,
+        }
+
+        # Full projection: all details for detailed view
+        full_projection = {
+            'Name': 1,
+            'Ort': 1,
+            'Beschreibung': 1,
+            'Filter': 1,
+            'Filter2': 1,
+            'Filter3': 1,
+            'Code_4': 1,
+            'Images': 1,
+            'ThumbnailInfo': 1,
+            'Verfuegbar': 1,
+            'User': 1,
+            'BorrowerInfo': 1,
+            'appointments': 1,
+            'BlockedNow': 1,
+            'Reservierbar': 1,
+            'DamageReports': 1,
+            'ISBN': 1,
+            'Author': 1,
+            'Autor': 1,
+            'Anschaffungsjahr': 1,
+            'Anschaffungskosten': 1,
+            'Condition': 1,
+            'HasDamage': 1,
+            'ItemType': 1,
+            'SeriesGroupId': 1,
+            'LastUpdated': 1,
+        }
+
+        parent_projection = light_projection if light_mode else full_projection
+
+        items_cur = items_col.find(base_query, parent_projection).sort([('Name', 1), ('_id', 1)])
         if pagination_requested:
             items_cur = items_cur.skip(offset).limit(limit)
 
-        items = []
-        for itm in items_cur:
-            item_id_str = str(itm['_id'])
-            grouped_children = list(items_col.find({
-                'ParentItemId': item_id_str,
+        parent_items = list(items_cur)
+        parent_ids = [str(item.get('_id')) for item in parent_items if item.get('_id') is not None]
+
+        children_by_parent = {}
+        if parent_ids:
+            # Light mode: minimal child data for counting only
+            light_child_projection = {
+                '_id': 1,
+                'ParentItemId': 1,
+                'Code_4': 1,
+                'Verfuegbar': 1,
+                'Name': 1,
+            }
+            # Full mode: complete child data with all details
+            full_child_projection = {
+                '_id': 1,
+                'ParentItemId': 1,
+                'Code_4': 1,
+                'Verfuegbar': 1,
+                'Name': 1,
+                'Images': 1,
+                'ThumbnailInfo': 1,
+                'Beschreibung': 1,
+            }
+            child_projection = light_child_projection if light_mode else full_child_projection
+            
+            child_cursor = items_col.find({
+                'ParentItemId': {'$in': parent_ids},
                 'IsGroupedSubItem': True,
                 'Deleted': {'$ne': True},
-            }))
+            }, child_projection)
+            for child in child_cursor:
+                parent_id = str(child.get('ParentItemId') or '')
+                if not parent_id:
+                    continue
+                children_by_parent.setdefault(parent_id, []).append(child)
+
+        items = []
+        for itm in parent_items:
+            item_id_str = str(itm['_id'])
+            grouped_children = children_by_parent.get(item_id_str, [])
             grouped_count = 1 + len(grouped_children)
 
             grouped_units = [itm] + grouped_children
@@ -3028,6 +3118,7 @@ def get_items():
             'limit': limit if limit is not None else count,
             'count': count,
             'total': total_count,
+            'light_mode': light_mode,
             'has_more': pagination_requested and ((offset + count) < total_count)
         })
     except Exception as e:

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/settings.py

@@ -12,6 +12,7 @@ defaults for the web application and helper modules.
 """
 import os
 import json
+from pymongo import MongoClient as _PyMongoClient
 
 # Base directory of this Web package
 BASE_DIR = os.path.dirname(os.path.abspath(__file__))
@@ -173,3 +174,21 @@ 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)
+
+
+def MongoClient(*args, **kwargs):
+    """Return a lightweight MongoDB client configured from this settings module."""
+    client_kwargs = {
+        'maxPoolSize': 10,
+        'minPoolSize': 0,
+        'connectTimeoutMS': 5000,
+        'serverSelectionTimeoutMS': 5000,
+        'retryWrites': True,
+    }
+    client_kwargs.update(kwargs)
+
+    # Preserve caller-provided positional host/port arguments.
+    # If none are passed, use configured defaults.
+    if args:
+        return _PyMongoClient(*args, **client_kwargs)
+    return _PyMongoClient(MONGODB_HOST, MONGODB_PORT, **client_kwargs)

Web/templates/main.html

@@ -725,9 +725,74 @@
     let allItems = [];
 
     const MAIN_ITEMS_PAGE_SIZE = 120;
+    let mainItemsNextOffset = 0;
+    let mainItemsHasMore = false;
+    let mainItemsLoadingMore = false;
+    let mainItemsLightMode = true;  // Track if we're in light mode to gradually request full data
+    let mainItemsObserver = null;
+    let mainItemsSentinel = null;
+    let mainItemsLoadingIndicator = null;
+    let mainItemsScrollPrefetchBound = false;
+
+    function ensureMainItemsLoadingIndicator() {
+        const itemsContainer = document.querySelector('#items-container');
+        if (!itemsContainer) return null;
+
+        if (!mainItemsLoadingIndicator) {
+            mainItemsLoadingIndicator = document.createElement('div');
+            mainItemsLoadingIndicator.id = 'main-items-loading-indicator';
+            mainItemsLoadingIndicator.className = 'items-loading-indicator';
+            mainItemsLoadingIndicator.innerHTML = `
+                <div class="loading-track"><div class="loading-fill"></div></div>
+                <div class="loading-label">Weitere Objekte werden vorbereitet...</div>
+            `;
+        }
+
+        itemsContainer.appendChild(mainItemsLoadingIndicator);
+        return itemsContainer;
+    }
+
+    function updateMainItemsLoadingIndicator() {
+        const itemsContainer = ensureMainItemsLoadingIndicator();
+        if (!itemsContainer || !mainItemsLoadingIndicator) return;
+
+        const shouldShow = mainItemsHasMore || mainItemsLoadingMore;
+        mainItemsLoadingIndicator.style.display = shouldShow ? 'flex' : 'none';
+        mainItemsLoadingIndicator.classList.toggle('is-loading', mainItemsLoadingMore);
+
+        const label = mainItemsLoadingIndicator.querySelector('.loading-label');
+        if (label) {
+            label.textContent = mainItemsLoadingMore
+                ? 'Weitere Objekte werden geladen...'
+                : 'Weitere Objekte werden vorbereitet...';
+        }
+    }
+
+    function maybePrefetchMainItems() {
+        const itemsContainer = document.querySelector('#items-container');
+        if (!itemsContainer || !mainItemsHasMore || mainItemsLoadingMore) {
+            return;
+        }
+
+        const distanceToEnd = itemsContainer.scrollWidth - (itemsContainer.scrollLeft + itemsContainer.clientWidth);
+        const prefetchThreshold = Math.max(260, itemsContainer.clientWidth * 1.4);
+        if (distanceToEnd > prefetchThreshold) {
+            return;
+        }
+
+        mainItemsLoadingMore = true;
+        updateMainItemsLoadingIndicator();
+        loadItems(mainItemsNextOffset, true).finally(() => {
+            mainItemsLoadingMore = false;
+            updateMainItemsLoadingIndicator();
+        });
+    }
 
     function loadItems(offset = 0, append = false) {
-        fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ITEMS_PAGE_SIZE}`)
+        // Für Pages nach der ersten: Explizit vollständige Daten laden (light_mode=false)
+        // Erste Page: light_mode wird automatisch enablet
+        const lightModeParam = offset > 0 ? '&light_mode=false' : '';
+        return fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ITEMS_PAGE_SIZE}${lightModeParam}`)
             .then(response => response.json())
             .then(data => {
                 const itemsContainer = document.querySelector('#items-container');
@@ -1009,7 +1074,7 @@
                 populateFilterOptions('filter2-options', [...filter2Values].sort(), 2);
                 populateFilterOptions('filter3-options', [...filter3Values].sort(), 3);
                 
-                // Start display from leftmost position (first card, which is now Z)
+                // Start display from leftmost position on full reload only.
                 if (!append) {
                     itemsContainer.scrollLeft = 0;
                 }
@@ -1028,18 +1093,17 @@
                     rebuildFilter3Options();
                 }
 
-                if (data.has_more) {
-                    const nextOffset = (data.offset || offset) + (data.count || pageItems.length);
-                    const continueLoad = () => loadItems(nextOffset, true);
-                    if ('requestIdleCallback' in window) {
-                        requestIdleCallback(continueLoad, { timeout: 250 });
-                    } else {
-                        setTimeout(continueLoad, 0);
-                    }
-                }
+                mainItemsNextOffset = (data.offset || offset) + (data.count || pageItems.length);
+                mainItemsHasMore = Boolean(data.has_more);
+                updateMainItemsLoadingIndicator();
+                setupMainItemsLazyLoading();
+                maybePrefetchMainItems();
             })
             .catch(error => {
                 console.error('Error fetching items:', error);
+                mainItemsLoadingMore = false;
+                mainItemsHasMore = false;
+                updateMainItemsLoadingIndicator();
                 if (append) {
                     return;
                 }
@@ -1049,6 +1113,72 @@
             });
     }
 
+    function ensureMainItemsSentinel() {
+        const itemsContainer = document.querySelector('#items-container');
+        if (!itemsContainer) return null;
+
+        ensureMainItemsLoadingIndicator();
+
+        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 (!mainItemsScrollPrefetchBound) {
+            itemsContainer.addEventListener('scroll', maybePrefetchMainItems, { passive: true });
+            mainItemsScrollPrefetchBound = true;
+        }
+
+        if (!mainItemsHasMore) return;
+
+        mainItemsObserver = new IntersectionObserver(entries => {
+            if (!entries.some(entry => entry.isIntersecting)) {
+                return;
+            }
+
+            if (mainItemsLoadingMore || !mainItemsHasMore) {
+                return;
+            }
+
+            mainItemsLoadingMore = true;
+            updateMainItemsLoadingIndicator();
+            loadItems(mainItemsNextOffset, true).finally(() => {
+                mainItemsLoadingMore = false;
+                updateMainItemsLoadingIndicator();
+            });
+        }, {
+            root: itemsContainer,
+            threshold: 0.15,
+            rootMargin: '0px 900px 0px 0px'
+        });
+
+        mainItemsObserver.observe(mainItemsSentinel);
+        updateMainItemsLoadingIndicator();
+    }
+
     function searchByCode() {
         const searchInput = document.getElementById('code-search');
         const rawSearchTerm = searchInput.value;
@@ -2766,6 +2896,57 @@
         scroll-behavior: smooth;
     }
 
+    .items-loading-indicator {
+        display: none;
+        flex: 0 0 220px;
+        min-width: 220px;
+        max-width: 220px;
+        height: 180px;
+        align-self: center;
+        margin-right: 8px;
+        border: 1px solid #dbe3ee;
+        border-radius: 10px;
+        background: #f8fafc;
+        color: #334155;
+        justify-content: center;
+        align-items: center;
+        flex-direction: column;
+        gap: 10px;
+        scroll-snap-align: center;
+    }
+
+    .items-loading-indicator .loading-label {
+        font-size: 0.84rem;
+        text-align: center;
+        line-height: 1.3;
+        max-width: 170px;
+    }
+
+    .items-loading-indicator .loading-track {
+        width: 160px;
+        height: 8px;
+        border-radius: 999px;
+        background: #e2e8f0;
+        overflow: hidden;
+    }
+
+    .items-loading-indicator .loading-fill {
+        width: 45%;
+        height: 100%;
+        border-radius: inherit;
+        background: linear-gradient(90deg, #60a5fa, #2563eb);
+        transform: translateX(-100%);
+    }
+
+    .items-loading-indicator.is-loading .loading-fill {
+        animation: items-loader-slide 1.05s ease-in-out infinite;
+    }
+
+    @keyframes items-loader-slide {
+        0% { transform: translateX(-100%); }
+        100% { transform: translateX(260%); }
+    }
+
     .item-card {
         background-color: #fff;
         border: 1px solid #ddd;

Web/templates/main_admin.html

@@ -323,6 +323,57 @@
         scroll-behavior: smooth;
     }
 
+    .items-loading-indicator {
+        display: none;
+        flex: 0 0 220px;
+        min-width: 220px;
+        max-width: 220px;
+        height: 180px;
+        align-self: center;
+        margin-right: 8px;
+        border: 1px solid #dbe3ee;
+        border-radius: 10px;
+        background: #f8fafc;
+        color: #334155;
+        justify-content: center;
+        align-items: center;
+        flex-direction: column;
+        gap: 10px;
+        scroll-snap-align: center;
+    }
+
+    .items-loading-indicator .loading-label {
+        font-size: 0.84rem;
+        text-align: center;
+        line-height: 1.3;
+        max-width: 170px;
+    }
+
+    .items-loading-indicator .loading-track {
+        width: 160px;
+        height: 8px;
+        border-radius: 999px;
+        background: #e2e8f0;
+        overflow: hidden;
+    }
+
+    .items-loading-indicator .loading-fill {
+        width: 45%;
+        height: 100%;
+        border-radius: inherit;
+        background: linear-gradient(90deg, #60a5fa, #2563eb);
+        transform: translateX(-100%);
+    }
+
+    .items-loading-indicator.is-loading .loading-fill {
+        animation: items-loader-slide 1.05s ease-in-out infinite;
+    }
+
+    @keyframes items-loader-slide {
+        0% { transform: translateX(-100%); }
+        100% { transform: translateX(260%); }
+    }
+
     .item-card {
         background-color: #fff;
         border: 1px solid #ddd;
@@ -2966,9 +3017,9 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 if (parsedFilters.filter3) activeFilters.filter3 = parsedFilters.filter3;
                 
                 // Update UI to show selected filters
-                updateSelectedFilters(1);
-                updateSelectedFilters(2);
-                updateSelectedFilters(3);
+                updateSelectedFiltersDisplay(1);
+                updateSelectedFiltersDisplay(2);
+                updateSelectedFiltersDisplay(3);
                 
                 // We'll rebuild Filter 3 options after items are loaded
             } catch (e) {
@@ -3256,9 +3307,75 @@ document.addEventListener('DOMContentLoaded', ()=>{
 
     // Function to load items from server
     const MAIN_ADMIN_ITEMS_PAGE_SIZE = 120;
+    let mainAdminItemsNextOffset = 0;
+    let mainAdminItemsHasMore = false;
+    let mainAdminItemsLoadingMore = false;
+    let mainAdminLightMode = true;  // Track if we're in light mode to gradually request full data
+    let mainAdminItemsObserver = null;
+    let mainAdminItemsSentinel = null;
+    let mainAdminItemsLoadingIndicator = null;
+    let mainAdminItemsScrollPrefetchBound = false;
+    let totalItemsInSystem = 0;
+
+    function ensureMainAdminItemsLoadingIndicator() {
+        const itemsContainer = document.querySelector('#items-container');
+        if (!itemsContainer) return null;
+
+        if (!mainAdminItemsLoadingIndicator) {
+            mainAdminItemsLoadingIndicator = document.createElement('div');
+            mainAdminItemsLoadingIndicator.id = 'main-admin-items-loading-indicator';
+            mainAdminItemsLoadingIndicator.className = 'items-loading-indicator';
+            mainAdminItemsLoadingIndicator.innerHTML = `
+                <div class="loading-track"><div class="loading-fill"></div></div>
+                <div class="loading-label">Weitere Objekte werden vorbereitet...</div>
+            `;
+        }
+
+        itemsContainer.appendChild(mainAdminItemsLoadingIndicator);
+        return itemsContainer;
+    }
+
+    function updateMainAdminItemsLoadingIndicator() {
+        const itemsContainer = ensureMainAdminItemsLoadingIndicator();
+        if (!itemsContainer || !mainAdminItemsLoadingIndicator) return;
+
+        const shouldShow = mainAdminItemsHasMore || mainAdminItemsLoadingMore;
+        mainAdminItemsLoadingIndicator.style.display = shouldShow ? 'flex' : 'none';
+        mainAdminItemsLoadingIndicator.classList.toggle('is-loading', mainAdminItemsLoadingMore);
+
+        const label = mainAdminItemsLoadingIndicator.querySelector('.loading-label');
+        if (label) {
+            label.textContent = mainAdminItemsLoadingMore
+                ? 'Weitere Objekte werden geladen...'
+                : 'Weitere Objekte werden vorbereitet...';
+        }
+    }
+
+    function maybePrefetchMainAdminItems() {
+        const itemsContainer = document.querySelector('#items-container');
+        if (!itemsContainer || !mainAdminItemsHasMore || mainAdminItemsLoadingMore) {
+            return;
+        }
+
+        const distanceToEnd = itemsContainer.scrollWidth - (itemsContainer.scrollLeft + itemsContainer.clientWidth);
+        const prefetchThreshold = Math.max(260, itemsContainer.clientWidth * 1.4);
+        if (distanceToEnd > prefetchThreshold) {
+            return;
+        }
+
+        mainAdminItemsLoadingMore = true;
+        updateMainAdminItemsLoadingIndicator();
+        loadItems(mainAdminItemsNextOffset, true).finally(() => {
+            mainAdminItemsLoadingMore = false;
+            updateMainAdminItemsLoadingIndicator();
+        });
+    }
 
     function loadItems(offset = 0, append = false) {
-        fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ADMIN_ITEMS_PAGE_SIZE}`)
+        // Für Pages nach der ersten: Explizit vollständige Daten laden (light_mode=false)
+        // Erste Page: light_mode wird automatisch enablet
+        const lightModeParam = offset > 0 ? '&light_mode=false' : '';
+        return fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ADMIN_ITEMS_PAGE_SIZE}${lightModeParam}`)
             .then(response => response.json())
             .then(data => {
                 const itemsContainer = document.querySelector('#items-container');
@@ -3270,6 +3387,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 const filter3Values = new Set();
                 const pageItems = data.items || [];
                 allItems = append ? allItems.concat(pageItems) : pageItems;
+                totalItemsInSystem = Number(data.total || totalItemsInSystem || pageItems.length || 0);
                 if (!append) {
                     itemsContainer.innerHTML = '';
                 }
@@ -3286,9 +3404,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                     return;
                 }
                 if (itemsIndicator) {
-                    const shownCount = allItems.length;
-                    const totalCount = Number(data.total || shownCount);
-                    itemsIndicator.textContent = `Objekte im System: ${shownCount}${data.has_more ? ` / ${totalCount} (lädt...)` : ''}`;
+                    itemsIndicator.textContent = `Objekte im System: ${totalItemsInSystem}${data.has_more ? ' (lädt...)' : ''}`;
                 }
                 pageItems.sort((a, b) => {
                     const nameA = a.Name ? a.Name.toLowerCase() : '';
@@ -3556,18 +3672,17 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 }
                 /* favorites render count removed */
 
-                if (data.has_more) {
-                    const nextOffset = (data.offset || offset) + (data.count || pageItems.length);
-                    const continueLoad = () => loadItems(nextOffset, true);
-                    if ('requestIdleCallback' in window) {
-                        requestIdleCallback(continueLoad, { timeout: 250 });
-                    } else {
-                        setTimeout(continueLoad, 0);
-                    }
-                }
+                mainAdminItemsNextOffset = (data.offset || offset) + (data.count || pageItems.length);
+                mainAdminItemsHasMore = Boolean(data.has_more);
+                updateMainAdminItemsLoadingIndicator();
+                setupMainAdminItemsLazyLoading();
+                maybePrefetchMainAdminItems();
             })
             .catch(error => {
                 console.error('Error fetching items:', error);
+                mainAdminItemsLoadingMore = false;
+                mainAdminItemsHasMore = false;
+                updateMainAdminItemsLoadingIndicator();
                 if (append) {
                     return;
                 }
@@ -3581,6 +3696,67 @@ document.addEventListener('DOMContentLoaded', ()=>{
             });
     }
 
+    function ensureMainAdminItemsSentinel() {
+        const itemsContainer = document.querySelector('#items-container');
+        if (!itemsContainer) return null;
+
+        ensureMainAdminItemsLoadingIndicator();
+
+        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 (!mainAdminItemsScrollPrefetchBound) {
+            itemsContainer.addEventListener('scroll', maybePrefetchMainAdminItems, { passive: true });
+            mainAdminItemsScrollPrefetchBound = true;
+        }
+
+        if (!mainAdminItemsHasMore) return;
+
+        mainAdminItemsObserver = new IntersectionObserver(entries => {
+            if (!entries.some(entry => entry.isIntersecting)) {
+                return;
+            }
+
+            if (mainAdminItemsLoadingMore || !mainAdminItemsHasMore) {
+                return;
+            }
+
+            mainAdminItemsLoadingMore = true;
+            updateMainAdminItemsLoadingIndicator();
+            loadItems(mainAdminItemsNextOffset, true).finally(() => {
+                mainAdminItemsLoadingMore = false;
+                updateMainAdminItemsLoadingIndicator();
+            });
+        }, {
+            root: itemsContainer,
+            threshold: 0.15,
+            rootMargin: '0px 900px 0px 0px'
+        });
+
+        mainAdminItemsObserver.observe(mainAdminItemsSentinel);
+        updateMainAdminItemsLoadingIndicator();
+    }
+
     function searchByCode() {
         const searchInput = document.getElementById('code-search');
         const rawSearchTerm = searchInput.value;
@@ -3675,7 +3851,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
         });
 
         if (itemsIndicator) {
-            itemsIndicator.textContent = `Objekte im System: ${allItems.length} | Angezeigt: ${visibleCount}`;
+            itemsIndicator.textContent = `Objekte im System: ${totalItemsInSystem || allItems.length} | Angezeigt: ${visibleCount}`;
         }
         
         if (isCodeSearch && visibleCount > 0 && (codeMatchCount > 0 || exactMatchCount > 0)) {

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):