feat: implement DOM virtualization for item cards in main and admin templates

Web/app.py

@@ -8587,11 +8587,13 @@ def manage_filters():
     # Get predefined filter values
     filter1_values = it.get_predefined_filter_values(1)
     filter2_values = it.get_predefined_filter_values(2)
+    filter3_values = it.get_predefined_filter_values(3)
     
     return render_template(
         'manage_filters.html',
         filter1_values=filter1_values,
         filter2_values=filter2_values,
+        filter3_values=filter3_values,
         library_module_enabled=cfg.MODULES.is_enabled('library'),
         student_cards_module_enabled=cfg.MODULES.is_enabled('student_cards')
     )

Web/items.py

@@ -570,7 +570,10 @@ def get_primary_filters():
         items = db['items']
         filters = [f for f in items.distinct('Filter', _active_record_query(_non_library_query())) if f]
         client.close()
-        return filters
+        
+        # Add predefined values
+        predefined = get_predefined_filter_values(1)
+        return sorted(list(set(filters + predefined)))
     except Exception as e:
         print(f"Error retrieving primary filters: {e}")
         return []
@@ -589,7 +592,10 @@ def get_secondary_filters():
         items = db['items']
         filters = [f for f in items.distinct('Filter2', _active_record_query(_non_library_query())) if f]
         client.close()
-        return filters
+        
+        # Add predefined values
+        predefined = get_predefined_filter_values(2)
+        return sorted(list(set(filters + predefined)))
     except Exception as e:
         print(f"Error retrieving secondary filters: {e}")
         return []
@@ -608,7 +614,10 @@ def get_tertiary_filters():
         items = db['items']
         filters = [f for f in items.distinct('Filter3', _active_record_query(_non_library_query())) if f]
         client.close()
-        return filters
+        
+        # Add predefined values
+        predefined = get_predefined_filter_values(3)
+        return sorted(list(set(filters + predefined)))
     except Exception as e:
         print(f"Error retrieving tertiary filters: {e}")
         return []

Web/templates/main.html

@@ -751,6 +751,7 @@
     let mainItemsSentinel = null;
     let mainItemsLoadingIndicator = null;
     let mainItemsScrollPrefetchBound = false;
+    let cardVirtualizationObserver = null;
 
     function ensureMainItemsLoadingIndicator() {
         const itemsContainer = document.querySelector('#items-container');
@@ -1189,6 +1190,55 @@
             mainItemsScrollPrefetchBound = true;
         }
 
+        // Setup DOM virtualization for items
+        if (!cardVirtualizationObserver) {
+            cardVirtualizationObserver = new IntersectionObserver((entries) => {
+                entries.forEach(entry => {
+                    const card = entry.target;
+                    if (entry.isIntersecting) {
+                        if (card.dataset.deloaded === 'true') {
+                            card.innerHTML = card.dataset.savedHtml;
+                            card.dataset.deloaded = 'false';
+                            card.classList.remove('is-deloaded');
+                            const favBtn = card.querySelector('.bookmark-btn');
+                            if (favBtn) {
+                                favBtn.addEventListener('click', (ev) => {
+                                    ev.stopPropagation();
+                                    toggleFavorite(card.dataset.itemId, favBtn, card);
+                                });
+                            }
+                            const cardContent = card.querySelector('.card-content');
+                            if (cardContent) {
+                                cardContent.addEventListener('click', function(e) {
+                                    if (e.target.tagName === 'BUTTON' || e.target.tagName === 'A' || e.target.tagName === 'INPUT' ||
+                                        e.target.closest('button') || e.target.closest('a') || e.target.closest('.image-container')) return;
+                                    e.stopPropagation();
+                                    openItemQuick(card.dataset.itemId);
+                                });
+                            }
+                        }
+                    } else {
+                        if (card.dataset.deloaded !== 'true') {
+                            const rect = card.getBoundingClientRect();
+                            if (rect.height > 50) {
+                                card.style.minHeight = rect.height + 'px';
+                                card.dataset.itemId = card.querySelector('.card-content')?.dataset.itemId || '';
+                                card.dataset.savedHtml = card.innerHTML;
+                                card.innerHTML = '';
+                                card.dataset.deloaded = 'true';
+                                card.classList.add('is-deloaded');
+                            }
+                        }
+                    }
+                });
+            }, {
+                rootMargin: isMobileLayout ? '1500px 0px 1500px 0px' : '0px 2500px 0px 2500px'
+            });
+        }
+        
+        // Observe all valid cards
+        document.querySelectorAll('.item-card').forEach(card => cardVirtualizationObserver.observe(card));
+
         if (!mainItemsHasMore) return;
 
         mainItemsObserver = new IntersectionObserver(entries => {
@@ -2419,29 +2469,29 @@
     // Add these functions right after the loadFilterState() function
 
     function rebuildFilter3Options() {
-        if (!allItems || allItems.length === 0) return;
+        if (!allItems) return;
         
         // Get current filter 1 and filter 2 selections
         const filter1Selections = activeFilters.filter1;
         const filter2Selections = activeFilters.filter2;
         
-        // If both filters are empty, show all filter3 values
+        // If both filters are empty, show all filter3 values from server
         if (filter1Selections.length === 0 && filter2Selections.length === 0) {
-            // Get all unique filter3 values
-            const allFilter3Values = new Set();
+            // Include dynamically added ones from loaded items too, just in case
+            const combinedFilter3Values = new Set(typeof allFilter3Values !== 'undefined' ? [...allFilter3Values] : []);
             allItems.forEach(item => {
                 const filter3Array = Array.isArray(item.Filter3) ? item.Filter3 : 
                                    (item.Filter3 ? [item.Filter3] : []);
                 
                 filter3Array.forEach(value => {
                     if (value && typeof value === 'string' && value.trim() !== '') {
-                        allFilter3Values.add(value);
+                        combinedFilter3Values.add(value);
                     }
                 });
             });
             
             // Populate filter 3 dropdown with all values
-            populateFilterOptions('filter3-options', [...allFilter3Values].sort(), 3);
+            populateFilterOptions('filter3-options', [...combinedFilter3Values].sort(), 3);
             return;
         }
         
@@ -3114,6 +3164,8 @@
         cursor: pointer;
         transition: transform 0.2s, box-shadow 0.2s;
         position: relative;
+        content-visibility: auto;
+        contain-intrinsic-size: 300px 450px;
     }
     .item-card:hover {
         transform: translateY(-5px);

Web/templates/main_admin.html

@@ -403,6 +403,8 @@
         cursor: pointer;
         transition: transform 0.2s, box-shadow 0.2s;
         position: relative;
+        content-visibility: auto;
+        contain-intrinsic-size: 300px 450px;
     }
 
     .item-card.bulk-selected {
@@ -2876,30 +2878,29 @@ document.addEventListener('DOMContentLoaded', ()=>{
     }
 
     function rebuildFilter3Options() {
-        if (!allItems || allItems.length === 0) return;
+        if (!allItems) return;
         
         // Get current filter 1 and filter 2 selections
         const filter1Selections = activeFilters.filter1;
         const filter2Selections = activeFilters.filter2;
         
-        // If both filters are empty, show all filter3 values
+        // If both filters are empty, show all filter3 values from server
         if (filter1Selections.length === 0 && filter2Selections.length === 0) {
-            // Get all unique filter3 values
-            const allFilter3Values = new Set();
+            // Include dynamically added ones from loaded items too, just in case
+            const combinedFilter3Values = new Set(typeof allFilter3Values !== 'undefined' ? [...allFilter3Values] : []);
             allItems.forEach(item => {
                 const filter3Array = Array.isArray(item.Filter3) ? item.Filter3 : 
-                                     (item.Filter3 ? [item.Filter3] : []);
+                                   (item.Filter3 ? [item.Filter3] : []);
                 
                 filter3Array.forEach(value => {
                     if (value && typeof value === 'string' && value.trim() !== '') {
-                        allFilter3Values.add(value);
+                        combinedFilter3Values.add(value);
                     }
                 });
             });
             
             // Populate filter 3 dropdown with all values
-            populateFilterOptions('filter3-options', [...allFilter3Values].sort(), 3);
-            return;
+            populateFilterOptions('filter3-options', [...combinedFilter3Values].sort(), 3);
         }
         
         // Filter items based on filter1 and filter2 selections
@@ -3356,6 +3357,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
     let mainAdminItemsLoadingIndicator = null;
     let mainAdminItemsScrollPrefetchBound = false;
     let totalItemsInSystem = 0;
+    let cardVirtualizationObserver = null;
 
     function ensureMainAdminItemsLoadingIndicator() {
         const itemsContainer = document.querySelector('#items-container');
@@ -3783,6 +3785,56 @@ document.addEventListener('DOMContentLoaded', ()=>{
             mainAdminItemsScrollPrefetchBound = true;
         }
 
+        // Setup DOM virtualization for items
+        if (!cardVirtualizationObserver) {
+            cardVirtualizationObserver = new IntersectionObserver((entries) => {
+                entries.forEach(entry => {
+                    const card = entry.target;
+                    if (entry.isIntersecting) {
+                        if (card.dataset.deloaded === 'true') {
+                            card.innerHTML = card.dataset.savedHtml;
+                            card.dataset.deloaded = 'false';
+                            card.classList.remove('is-deloaded');
+                            const favBtn = card.querySelector('.bookmark-btn');
+                            if (favBtn) {
+                                favBtn.addEventListener('click', (ev) => {
+                                    ev.stopPropagation();
+                                    toggleFavorite(card.dataset.itemId, favBtn, card);
+                                });
+                            }
+                            const cardContent = card.querySelector('.card-content');
+                            if (cardContent) {
+                                cardContent.addEventListener('click', function(e) {
+                                    if (e.target.tagName === 'BUTTON' || e.target.tagName === 'A' || e.target.tagName === 'INPUT' ||
+                                        e.target.closest('button') || e.target.closest('a') || e.target.closest('.image-container') ||
+                                        e.target.closest('.bulk-delete-toggle') || e.target.closest('label')) return;
+                                    e.stopPropagation();
+                                    openItemQuick(card.dataset.itemId);
+                                });
+                            }
+                        }
+                    } else {
+                        if (card.dataset.deloaded !== 'true') {
+                            const rect = card.getBoundingClientRect();
+                            if (rect.height > 50) {
+                                card.style.minHeight = rect.height + 'px';
+                                card.dataset.itemId = card.querySelector('.card-content')?.dataset.itemId || '';
+                                card.dataset.savedHtml = card.innerHTML;
+                                card.innerHTML = '';
+                                card.dataset.deloaded = 'true';
+                                card.classList.add('is-deloaded');
+                            }
+                        }
+                    }
+                });
+            }, {
+                rootMargin: isMobileLayout ? '1500px 0px 1500px 0px' : '0px 2500px 0px 2500px'
+            });
+        }
+        
+        // Observe all valid cards
+        document.querySelectorAll('.item-card').forEach(card => cardVirtualizationObserver.observe(card));
+
         if (!mainAdminItemsHasMore) return;
 
         mainAdminItemsObserver = new IntersectionObserver(entries => {

Web/templates/manage_filters.html

@@ -15,16 +15,16 @@
     <h1 class="mb-4">Filterwerte verwalten</h1>
     
     <div class="row">
-        <!-- Filter 1: Unterrichtsfach -->
-        <div class="col-md-6">
+        <!-- Filter 1 -->
+        <div class="col-md-4">
             <div class="card mb-4">
                 <div class="card-header">
-                    <h2 class="card-title h5 mb-0">Unterrichtsfach (Filter 1)</h2>
+                    <h2 class="card-title h5 mb-0">Fach/Kategorie (Filter 1)</h2>
                 </div>
                 <div class="card-body">
                     <form method="POST" action="{{ url_for('add_filter_value', filter_num=1) }}" class="mb-4">
                         <div class="input-group">
-                            <input type="text" name="value" class="form-control" placeholder="Neues Unterrichtsfach..." required>
+                            <input type="text" name="value" class="form-control" placeholder="Neuer Wert..." required>
                             <button type="submit" class="btn btn-primary">Hinzufügen</button>
                         </div>
                     </form>
@@ -51,16 +51,16 @@
             </div>
         </div>
         
-        <!-- Filter 2: Jahrgangsstufe -->
-        <div class="col-md-6">
+        <!-- Filter 2 -->
+        <div class="col-md-4">
             <div class="card mb-4">
                 <div class="card-header">
-                    <h2 class="card-title h5 mb-0">Jahrgangsstufe (Filter 2)</h2>
+                    <h2 class="card-title h5 mb-0">System/Bereich (Filter 2)</h2>
                 </div>
                 <div class="card-body">
                     <form method="POST" action="{{ url_for('add_filter_value', filter_num=2) }}" class="mb-4">
                         <div class="input-group">
-                            <input type="text" name="value" class="form-control" placeholder="Neue Jahrgangsstufe..." required>
+                            <input type="text" name="value" class="form-control" placeholder="Neuer Wert..." required>
                             <button type="submit" class="btn btn-primary">Hinzufügen</button>
                         </div>
                     </form>
@@ -86,6 +86,42 @@
                 </div>
             </div>
         </div>
+
+        <!-- Filter 3 -->
+        <div class="col-md-4">
+            <div class="card mb-4">
+                <div class="card-header">
+                    <h2 class="card-title h5 mb-0">Typ/Art (Filter 3)</h2>
+                </div>
+                <div class="card-body">
+                    <form method="POST" action="{{ url_for('add_filter_value', filter_num=3) }}" class="mb-4">
+                        <div class="input-group">
+                            <input type="text" name="value" class="form-control" placeholder="Neuer Wert..." required>
+                            <button type="submit" class="btn btn-primary">Hinzufügen</button>
+                        </div>
+                    </form>
+                    
+                    <h5 class="mb-3">Vorhandene Werte</h5>
+                    {% if filter3_values %}
+                    <div class="list-group">
+                        {% for value in filter3_values %}
+                        <div class="list-group-item d-flex justify-content-between align-items-center">
+                            {{ value }}
+                            <form method="POST" action="{{ url_for('remove_filter_value', filter_num=3, value=value) }}" class="d-inline">
+                                <button type="submit" class="btn btn-sm btn-danger"
+                                        onclick="return confirm('Sind Sie sicher, dass Sie den Wert \"' + '{{ value }}'.replace(/'/g, '\\\'') + '\" löschen möchten?');">
+                                    Entfernen
+                                </button>
+                            </form>
+                        </div>
+                        {% endfor %}
+                    </div>
+                    {% else %}
+                    <div class="alert alert-info">Keine Werte definiert.</div>
+                    {% endif %}
+                </div>
+            </div>
+        </div>
     </div>
     
     <div class="alert alert-warning">