Add damage report link to notification details

- Introduced a new audit logging system that creates a tamper-evident chain of events in MongoDB.
- Added functions for appending audit events, ensuring index integrity, and verifying the audit chain.
- Implemented soft-delete functionality for inventory and borrowing records to comply with GoBD regulations.
- Added UI components for displaying invoice corrections and audit dashboard, including mismatch reporting.
- Created a CLI utility for verifying the integrity of the audit chain.
- Enhanced invoice management by preventing overwrites and allowing correction entries with reasons and optional deltas.

.github/workflows/release-docker.yml

@@ -203,6 +203,7 @@ jobs:
               expose:
                 - "8000"
               volumes:
+                - ./config.json:/app/config.json:ro
                 - app_uploads:/app/Web/uploads
                 - app_thumbnails:/app/Web/thumbnails
                 - app_previews:/app/Web/previews
@@ -225,6 +226,7 @@ jobs:
           cp stop.sh release-bundle/stop.sh
           cp restart.sh release-bundle/restart.sh
           cp backup.sh release-bundle/backup.sh
+          cp config.json release-bundle/config.json
           cp update.sh release-bundle/update.sh
           cp init-admin.sh release-bundle/init-admin.sh
 

Dockerfile

@@ -32,4 +32,4 @@ RUN if [ "$NUITKA_BUILD" = "1" ]; then \
 WORKDIR /app/Web
 EXPOSE 8000
 
-CMD ["gunicorn", "app:app", "--bind", "0.0.0.0:8000", "--workers", "3", "--timeout", "60", "--graceful-timeout", "20", "--max-requests", "1000", "--max-requests-jitter", "100", "--log-level", "info", "--access-logfile", "-", "--error-logfile", "-"]
+CMD ["gunicorn", "app:app", "--bind", "0.0.0.0:8000", "--workers", "2", "--timeout", "30", "--graceful-timeout", "20", "--max-requests", "200", "--max-requests-jitter", "50", "--log-level", "info", "--access-logfile", "-", "--error-logfile", "-"]

Legal/GOBD_CHANGE_REPORT_2026-04-10.md

@@ -0,0 +1,180 @@
+# GoBD Hardening Change Report (2026-04-10)
+
+## Scope
+This change set implements core hardening measures for GoBD-oriented operation:
+
+1. Soft-delete instead of hard-delete for inventory and borrowing records.
+2. Tamper-evident audit log chain for critical accounting/inventory events.
+3. Invoice immutability model with correction entries instead of overwrite.
+
+## Implemented Changes
+
+### 1) Tamper-evident audit chain
+
+- New module: `Web/audit_log.py`
+- Audit entries are chained by hash (`prev_hash` -> `entry_hash`) with monotonic `chain_index`.
+- Canonical JSON serialization is used to make hashing deterministic.
+
+Current fields per audit event:
+- `event_type`
+- `actor`
+- `source`
+- `ip`
+- `payload`
+- `timestamp`
+- `created_at`
+- `prev_hash`
+- `entry_hash`
+- `chain_index`
+
+Integrated event writes in:
+- Item soft-delete flow
+- Invoice creation
+- Invoice paid marking
+- Invoice finalize+repair
+- Invoice correction entry creation
+
+### 1b) Audit operational controls (phase 2)
+
+- Added index management in `Web/audit_log.py`:
+   - Unique index on `chain_index`
+   - Additional indexes on `created_at` and `event_type`
+- Added chain verification function in `Web/audit_log.py`.
+- Added CLI verification tool: `Web/verify_audit_chain.py`.
+- Added admin verification endpoint:
+   - `GET /admin/audit/verify`
+   - Returns chain integrity result (`200` if valid, `409` on mismatch).
+- Added lazy index provisioning helper invoked in admin borrowing views.
+
+### 2) Soft-delete conversion
+
+#### Inventory items
+
+- Deletion endpoint now marks records logically deleted:
+  - `Deleted: true`
+  - `DeletedAt`
+  - `DeletedBy`
+  - `LastUpdated`
+  - `Verfuegbar: false`
+- Item-linked borrow records are also logically deleted (`Status: deleted`) instead of physically removed.
+- Image files are no longer physically deleted in this flow.
+
+#### Borrow records
+
+- `remove_ausleihung` changed to set `Status: deleted` + timestamps.
+- Retrieval helpers now exclude deleted records by default.
+
+#### Item reads
+
+- Item helper queries now exclude `Deleted: true` records.
+- Grouped item lookups and appointment queries also exclude deleted records.
+- Code uniqueness checks ignore deleted records, allowing controlled code reuse.
+
+### 3) Invoice immutability and correction flow
+
+- Invoice creation now blocks overwrite if an invoice already exists for the borrow record.
+- New lock marker on invoice creation/update path: `InvoiceLocked: true`.
+- New correction endpoint:
+  - `POST /admin/borrowings/<borrow_id>/invoice/correction`
+  - Appends entries to `InvoiceCorrections`
+  - Does not mutate existing `InvoiceData` body
+  - Requires correction reason
+  - Supports optional amount delta
+
+### 3b) UI integration for correction flow (phase 2)
+
+- Added correction action forms in:
+   - `Web/templates/admin_borrowings.html`
+   - `Web/templates/library_borrowings_admin.html`
+- Added correction count display (`invoice_corrections_count`) in both admin tables.
+
+## Detailed File-Level Review
+
+### `Web/audit_log.py`
+
+- Introduces chain-based audit persistence.
+- Uses last chain entry to calculate next `chain_index` and hash.
+- Adds explicit index provisioning and full chain verification routine.
+- Tradeoff: application-level sequencing is improved by unique index, but concurrent peak writes may still require retry logic around duplicate key conflicts.
+
+### `Web/verify_audit_chain.py`
+
+- New CLI operational tool for manual/cron verification.
+- Returns non-zero exit code on chain mismatch.
+
+### `Web/app.py`
+
+- Added `_append_audit_event(...)` helper and integrated it at critical event boundaries.
+- Inventory API routes now hide soft-deleted items.
+- `delete_item` changed from destructive deletion to soft-delete semantics.
+- Invoice route now rejects overwrite and requires correction route for changes.
+- Added correction route with immutable invoice core.
+- Added admin audit verification route and lazy audit index initialization helper.
+
+Behavioral impact:
+- Deleted items no longer disappear from DB; they are hidden from normal views.
+- Existing UI actions for delete continue to work, but now preserve evidence.
+- Invoice re-creation attempts now return warning and redirect.
+
+### `Web/items.py`
+
+- Introduced `_active_record_query(...)` and applied it across item retrieval APIs.
+- Converted `remove_item` to soft-delete update.
+- Updated maintenance reset (`unstuck_item`) to status updates instead of `delete_many`.
+
+Behavioral impact:
+- Item-level DB history is preserved.
+- Legacy scripts relying on hard delete semantics may need adaptation.
+
+### `Web/ausleihung.py`
+
+- Converted `remove_ausleihung` to soft-delete by status.
+- Default retrieval paths now exclude deleted records.
+
+Behavioral impact:
+- Borrowing history remains in DB for traceability.
+
+## Validation Performed
+
+- Static diagnostics reported no errors in modified files:
+  - `Web/app.py`
+  - `Web/items.py`
+  - `Web/ausleihung.py`
+  - `Web/audit_log.py`
+
+- Additional phase-2 checks:
+   - `python3 -m py_compile Web/app.py Web/audit_log.py Web/verify_audit_chain.py`
+   - No syntax errors
+   - Template diagnostics:
+      - `Web/templates/admin_borrowings.html` no errors
+      - `Web/templates/library_borrowings_admin.html` no errors
+
+## Residual Risks / Open Points
+
+1. Concurrency hardening for audit chain:
+   - Current chain append may produce collisions under parallel writes.
+   - Recommendation: transaction or optimistic retry with unique index on `chain_index`.
+
+2. Broader query coverage:
+   - Some direct Mongo queries outside helper paths may still need explicit `Deleted != true` filters.
+
+3. Formal GoBD process requirements beyond code:
+   - Verfahrensdokumentation must be updated.
+   - WORM/immutable storage for exported archives should be enforced externally.
+   - Operational controls (RBAC review, periodic reconciliation, restore drills) should be documented.
+
+## Recommended Next Steps
+
+1. Add retry strategy for audit write conflicts:
+   - Retry `append_audit_event` on duplicate `chain_index` key errors.
+
+2. Add admin UI page for chain status and recent audit events:
+   - Human-readable inspection view on top of `/admin/audit/verify`.
+
+3. Add policy enforcement tests:
+   - Ensure invoice overwrite is blocked.
+   - Ensure soft-deleted records are hidden in APIs.
+   - Ensure deletion endpoints never call physical delete operators.
+
+4. Infrastructure-level immutability:
+   - Push periodic audit snapshots and invoice archives to immutable/WORM storage.

README.md

@@ -1,5 +1,7 @@
 # Inventarsystem
 
+[![https://github.com/AIIrondev/legendary-octo-garbanzo](https://github.com/AIIrondev/legendary-octo-garbanzo/actions/workflows/release-docker.yml/badge.svg)](https://github.com/AIIrondev/legendary-octo-garbanzo/actions/workflows/release-docker.yml)
+
 [![wakatime](https://wakatime.com/badge/user/30b8509f-5e17-4d16-b6b8-3ca0f3f936d3/project/8a380b7f-389f-4a7e-8877-0fe9e1a4c243.svg)](https://wakatime.com/badge/user/30b8509f-5e17-4d16-b6b8-3ca0f3f936d3/project/8a380b7f-389f-4a7e-8877-0fe9e1a4c243)
 
 **Aktuelle Version: 3.2.1**

SECURITY.md

@@ -6,9 +6,10 @@ The latest version will allways be supported the rest are old version that are n
 
 | Version | Supported          |
 | ------- | ------------------ |
+| 0.2.17  | ✅                 |
 | 3.2.x   | :white_check_mark: |
 | 3.1.x   | :x:                |
-| 3.0.x   | :white_check_mark: |
+| 3.0.x   | :x: |
 | 2.6.x   | :x:                |
 | 2.4.x   | :x:                |
 | 1.8.x   | :x:                |

Web/audit_log.py

@@ -0,0 +1,149 @@
+"""
+Tamper-evident audit logging helpers.
+
+The audit chain stores each entry with a hash of the previous entry.
+Any mutation in history breaks the chain verification.
+"""
+
+import datetime
+import hashlib
+import json
+import random
+import time
+
+from pymongo.errors import DuplicateKeyError
+
+
+def _stable_json(value):
+    """Serialize dictionaries in a stable way for deterministic hashing."""
+    return json.dumps(value, sort_keys=True, separators=(",", ":"), ensure_ascii=False, default=str)
+
+
+def _entry_hash(prev_hash, payload):
+    """Build the chained entry hash from previous hash + canonical payload."""
+    base = f"{prev_hash}|{_stable_json(payload)}"
+    return hashlib.sha256(base.encode("utf-8")).hexdigest()
+
+
+def append_audit_event(db, event_type, actor, payload, request_ip=None, source="web", max_retries=5):
+    """
+    Append an audit event to a tamper-evident chain.
+
+    Args:
+        db: MongoDB database handle.
+        event_type (str): Event category.
+        actor (str): User/system who performed the action.
+        payload (dict): Event details.
+        request_ip (str, optional): Request origin.
+        source (str): Source subsystem.
+
+    Returns:
+        dict: Inserted audit entry.
+    """
+    logs = db["audit_log"]
+    attempts = 0
+
+    while attempts <= max_retries:
+        previous = logs.find_one(sort=[("chain_index", -1)])
+        prev_hash = previous.get("entry_hash", "") if previous else ""
+        chain_index = int(previous.get("chain_index", 0)) + 1 if previous else 1
+
+        timestamp = datetime.datetime.utcnow()
+        entry_payload = {
+            "event_type": event_type,
+            "actor": actor or "system",
+            "source": source,
+            "ip": request_ip or "",
+            "payload": payload or {},
+            "timestamp": timestamp.isoformat() + "Z",
+        }
+
+        entry_hash = _entry_hash(prev_hash, entry_payload)
+
+        entry = {
+            **entry_payload,
+            "created_at": timestamp,
+            "prev_hash": prev_hash,
+            "entry_hash": entry_hash,
+            "chain_index": chain_index,
+        }
+
+        try:
+            logs.insert_one(entry)
+            return entry
+        except DuplicateKeyError:
+            attempts += 1
+            if attempts > max_retries:
+                raise
+            # Exponential backoff with jitter to avoid retry storms.
+            delay = min(0.25, (0.005 * (2 ** attempts)) + random.random() * 0.01)
+            time.sleep(delay)
+
+
+def ensure_audit_indexes(db):
+    """Create indexes required for fast and safe audit operations."""
+    logs = db["audit_log"]
+    logs.create_index("chain_index", unique=True, name="audit_chain_index_unique")
+    logs.create_index("created_at", name="audit_created_at_idx")
+    logs.create_index("event_type", name="audit_event_type_idx")
+
+
+def verify_audit_chain(db):
+    """Verify hash chain integrity across all stored audit entries."""
+    logs = db["audit_log"]
+    entries = list(logs.find({}, {"_id": 1, "event_type": 1, "actor": 1, "source": 1, "ip": 1, "payload": 1, "timestamp": 1, "prev_hash": 1, "entry_hash": 1, "chain_index": 1}).sort("chain_index", 1))
+
+    previous_hash = ""
+    previous_index = 0
+    mismatches = []
+
+    for entry in entries:
+        chain_index = int(entry.get("chain_index", 0))
+        prev_hash = entry.get("prev_hash", "")
+        entry_hash = entry.get("entry_hash", "")
+
+        payload = {
+            "event_type": entry.get("event_type", ""),
+            "actor": entry.get("actor", ""),
+            "source": entry.get("source", ""),
+            "ip": entry.get("ip", ""),
+            "payload": entry.get("payload", {}),
+            "timestamp": entry.get("timestamp", ""),
+        }
+
+        expected_hash = _entry_hash(previous_hash, payload)
+
+        if chain_index != previous_index + 1:
+            mismatches.append({
+                "chain_index": chain_index,
+                "error": "chain_index_gap",
+                "expected": previous_index + 1,
+                "found": chain_index,
+            })
+
+        if prev_hash != previous_hash:
+            mismatches.append({
+                "chain_index": chain_index,
+                "error": "prev_hash_mismatch",
+                "expected": previous_hash,
+                "found": prev_hash,
+            })
+
+        if entry_hash != expected_hash:
+            mismatches.append({
+                "chain_index": chain_index,
+                "error": "entry_hash_mismatch",
+                "expected": expected_hash,
+                "found": entry_hash,
+            })
+
+        previous_hash = entry_hash
+        previous_index = chain_index
+
+    return {
+        "ok": len(mismatches) == 0,
+        "count": len(entries),
+        "last_chain_index": previous_index,
+        "last_hash": previous_hash,
+        "mismatches": mismatches,
+    }

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):
@@ -365,8 +365,7 @@ def cancel_ausleihung(id):
 
 def remove_ausleihung(id):
     """
-    Entfernt einen Ausleihungsdatensatz aus der Datenbank.
+    Markiert einen Ausleihungsdatensatz als gelöscht (Soft-Delete).
-    Hinweis: Normalerweise ist es besser, Datensätze zu markieren als sie zu löschen.
     
     Args:
         id (str): ID des zu entfernenden Ausleihungsdatensatzes
@@ -378,9 +377,17 @@ def remove_ausleihung(id):
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         ausleihungen = db['ausleihungen']
-        result = ausleihungen.delete_one({'_id': ObjectId(id)})
+        now = datetime.datetime.now()
+        result = ausleihungen.update_one(
+            {'_id': ObjectId(id), 'Status': {'$ne': 'deleted'}},
+            {'$set': {
+                'Status': 'deleted',
+                'DeletedAt': now,
+                'LastUpdated': now,
+            }}
+        )
         client.close()
-        return result.deleted_count > 0
+        return result.modified_count > 0
     except Exception as e:
         # print(f"Error removing ausleihung: {e}") # Log the error
         return False
@@ -429,14 +436,15 @@ def get_ausleihungen(status=None, start=None, end=None, date_filter='overlap'):
         collection = db['ausleihungen']
         
         # Query erstellen
-        query = {}
+        query = {'Status': {'$ne': 'deleted'}}
         
         # Status-Filter hinzufügen
         if status is not None:
             if isinstance(status, list):
-                query['Status'] = {'$in': status}
+                allowed_status = [s for s in status if s != 'deleted']
+                query['Status'] = {'$in': allowed_status}
             else:
-                query['Status'] = status
+                query['Status'] = status if status != 'deleted' else '__blocked_deleted_status__'
         
         # Datum parsen, wenn als String angegeben
         if start is not None and isinstance(start, str):
@@ -561,7 +569,7 @@ def get_ausleihung_by_user(user_id, status=None, use_client_side_verification=Tr
         db = client[cfg.MONGODB_DB]
         ausleihungen = db['ausleihungen']
         
-        query = {'User': user_id}
+        query = {'User': user_id, 'Status': {'$ne': 'deleted'}}
         
         # Wenn clientseitige Verifikation verwendet wird, holen wir ALLE Ausleihungen
         # und filtern später clientseitig
@@ -610,12 +618,12 @@ def get_ausleihung_by_user(user_id, status=None, use_client_side_verification=Tr
             
             # Status-Matching
             if isinstance(status, list):
-                if current_status in status:
+                if current_status in status and current_status != 'deleted':
                     # Status aktualisieren und zur Ergebnismenge hinzufügen
                     ausleihung['VerifiedStatus'] = current_status
                     filtered_results.append(ausleihung)
             else:
-                if current_status == status:
+                if current_status == status and current_status != 'deleted':
                     # Status aktualisieren und zur Ergebnismenge hinzufügen
                     ausleihung['VerifiedStatus'] = current_status
                     filtered_results.append(ausleihung)
@@ -644,7 +652,7 @@ def get_ausleihung_by_item(item_id, status=None, include_history=False):
         ausleihungen = db['ausleihungen']
         
         # Build query
-        query = {'Item': item_id}
+        query = {'Item': item_id, 'Status': {'$ne': 'deleted'}}
         if status and not include_history:
             query['Status'] = status
         

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')
@@ -43,6 +43,14 @@ def _non_library_query(extra_query=None):
     return base_query
 
 
+def _active_record_query(extra_query=None):
+    """Build a query that excludes logically deleted records."""
+    base_query = {'Deleted': {'$ne': True}}
+    if extra_query:
+        base_query.update(extra_query)
+    return base_query
+
+
 # === ITEM MANAGEMENT ===
 
 def add_item(name, ort, beschreibung, images=None, filter=None, filter2=None, filter3=None,
@@ -118,7 +126,7 @@ def add_item(name, ort, beschreibung, images=None, filter=None, filter2=None, fi
 
 def remove_item(id):
     """
-    Remove an item from the inventory.
+    Soft-delete an item from the inventory.
     
     Args:
         id (str): ID of the item to remove
@@ -130,9 +138,17 @@ def remove_item(id):
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        result = items.delete_one({'_id': ObjectId(id)})
+        result = items.update_one(
+            {'_id': ObjectId(id), 'Deleted': {'$ne': True}},
+            {'$set': {
+                'Deleted': True,
+                'DeletedAt': datetime.datetime.now(),
+                'LastUpdated': datetime.datetime.now(),
+                'Verfuegbar': False,
+            }}
+        )
         client.close()
-        return result.deleted_count > 0
+        return result.modified_count > 0
     except Exception as e:
         print(f"Error removing item: {e}")
         return False
@@ -155,7 +171,7 @@ def get_group_item_ids(id):
         db = client[cfg.MONGODB_DB]
         items = db['items']
 
-        base_item = items.find_one({'_id': ObjectId(id)})
+        base_item = items.find_one(_active_record_query({'_id': ObjectId(id)}))
         if not base_item:
             client.close()
             return []
@@ -165,7 +181,7 @@ def get_group_item_ids(id):
         # Prefer SeriesGroupId because it represents the full logical group.
         series_group_id = base_item.get('SeriesGroupId')
         if series_group_id:
-            for group_item in items.find({'SeriesGroupId': series_group_id}, {'_id': 1}):
+            for group_item in items.find(_active_record_query({'SeriesGroupId': series_group_id}), {'_id': 1}):
                 resolved_ids.add(str(group_item['_id']))
         else:
             resolved_ids.add(str(base_item['_id']))
@@ -173,10 +189,10 @@ def get_group_item_ids(id):
             parent_item_id = base_item.get('ParentItemId')
             if parent_item_id:
                 resolved_ids.add(str(parent_item_id))
-                for sibling in items.find({'ParentItemId': str(parent_item_id), 'IsGroupedSubItem': True}, {'_id': 1}):
+                for sibling in items.find(_active_record_query({'ParentItemId': str(parent_item_id), 'IsGroupedSubItem': True}), {'_id': 1}):
                     resolved_ids.add(str(sibling['_id']))
             else:
-                for child in items.find({'ParentItemId': str(base_item['_id']), 'IsGroupedSubItem': True}, {'_id': 1}):
+                for child in items.find(_active_record_query({'ParentItemId': str(base_item['_id']), 'IsGroupedSubItem': True}), {'_id': 1}):
                     resolved_ids.add(str(child['_id']))
 
         client.close()
@@ -342,7 +358,7 @@ def is_code_unique(code_4, exclude_id=None):
     items = db['items']
     
     # Build query to find items with this code
-    query = {'Code_4': code_4}
+    query = {'Code_4': code_4, 'Deleted': {'$ne': True}}
     
     # If we're editing an item, exclude it from the uniqueness check
     if exclude_id:
@@ -368,7 +384,7 @@ def get_items():
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        items_return = items.find(_non_library_query())
+        items_return = items.find(_active_record_query(_non_library_query()))
         items_list = []
         for item in items_return:
             item['_id'] = str(item['_id'])
@@ -391,7 +407,7 @@ def get_available_items():
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        items_return = items.find(_non_library_query({'Verfuegbar': True}))
+        items_return = items.find(_active_record_query(_non_library_query({'Verfuegbar': True})))
         items_list = []
         for item in items_return:
             item['_id'] = str(item['_id'])
@@ -414,7 +430,7 @@ def get_borrowed_items():
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        items_return = items.find(_non_library_query({'Verfuegbar': False}))
+        items_return = items.find(_active_record_query(_non_library_query({'Verfuegbar': False})))
         items_list = []
         for item in items_return:
             item['_id'] = str(item['_id'])
@@ -440,7 +456,7 @@ def get_item(id):
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        item = items.find_one({'_id': ObjectId(id)})
+        item = items.find_one(_active_record_query({'_id': ObjectId(id)}))
         client.close()
         return item
     except Exception as e:
@@ -462,7 +478,7 @@ def get_item_by_name(name):
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        item = items.find_one({'Name': name})
+        item = items.find_one(_active_record_query({'Name': name}))
         client.close()
         return item
     except Exception as e:
@@ -486,13 +502,13 @@ def get_items_by_filter(filter_value):
         items = db['items']
         
         # Use $or to find matches in any filter field
-        query = _non_library_query({
+        query = _active_record_query(_non_library_query({
             '$or': [
                 {'Filter': filter_value},
                 {'Filter2': filter_value},
                 {'Filter3': filter_value}
             ]
-        })
+        }))
         
         results = list(items.find(query))
         client.close()
@@ -518,7 +534,7 @@ def get_filters():
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        non_library = _non_library_query()
+        non_library = _active_record_query(_non_library_query())
         filters = items.distinct('Filter', non_library)
         filters2 = items.distinct('Filter2', non_library)
         filters3 = items.distinct('Filter3', non_library)
@@ -550,7 +566,7 @@ def get_primary_filters():
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        filters = [f for f in items.distinct('Filter', _non_library_query()) if f]
+        filters = [f for f in items.distinct('Filter', _active_record_query(_non_library_query())) if f]
         client.close()
         return filters
     except Exception as e:
@@ -569,7 +585,7 @@ def get_secondary_filters():
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        filters = [f for f in items.distinct('Filter2', _non_library_query()) if f]
+        filters = [f for f in items.distinct('Filter2', _active_record_query(_non_library_query())) if f]
         client.close()
         return filters
     except Exception as e:
@@ -588,7 +604,7 @@ def get_tertiary_filters():
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        filters = [f for f in items.distinct('Filter3', _non_library_query()) if f]
+        filters = [f for f in items.distinct('Filter3', _active_record_query(_non_library_query())) if f]
         client.close()
         return filters
     except Exception as e:
@@ -610,7 +626,7 @@ def get_item_by_code_4(code_4):
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         items = db['items']
-        results = list(items.find(_non_library_query({"Code_4": code_4})))
+        results = list(items.find(_active_record_query(_non_library_query({"Code_4": code_4}))))
         
         # Convert ObjectId to string
         for item in results:
@@ -640,7 +656,14 @@ def unstuck_item(id):
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = client[cfg.MONGODB_DB]
         ausleihungen = db['ausleihungen']
-        result = ausleihungen.delete_many({'Item': id})
+        result = ausleihungen.update_many(
+            {'Item': id, 'Status': {'$nin': ['cancelled', 'deleted']}},
+            {'$set': {
+                'Status': 'cancelled',
+                'CancelledReason': 'unstuck_reset',
+                'LastUpdated': datetime.datetime.now()
+            }}
+        )
         
         # Also reset the item status
         items = db['items']
@@ -980,7 +1003,7 @@ def get_items_with_appointments():
         db = client[cfg.MONGODB_DB]
         items = db['items']
         
-        items_return = items.find({'NextAppointment': {'$exists': True}})
+        items_return = items.find({'NextAppointment': {'$exists': True}, 'Deleted': {'$ne': True}})
         items_list = []
         for item in items_return:
             item['_id'] = str(item['_id'])

Web/requirements.txt

@@ -11,3 +11,4 @@ pytz
 requests
 reportlab
 python-barcode
+openpyxl

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/admin_audit.html

@@ -0,0 +1,94 @@
+{% extends 'base.html' %}
+{% block title %}Audit Dashboard - {{ APP_VERSION }}{% endblock %}
+{% block content %}
+<div class="container" style="max-width:1400px; margin:0 auto; padding:18px;">
+  <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>
+      {% if verify_result.ok %}
+      <div style="font-size:1.35rem; font-weight:700; color:#166534;">OK</div>
+      {% else %}
+      <div style="font-size:1.35rem; font-weight:700; color:#991b1b;">FEHLER</div>
+      {% endif %}
+    </div>
+    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background:#fff;">
+      <div style="font-size:0.85rem; color:#64748b;">Einträge</div>
+      <div style="font-size:1.35rem; font-weight:700;">{{ verify_result.count }}</div>
+    </div>
+    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background:#fff;">
+      <div style="font-size:0.85rem; color:#64748b;">Letzter Index</div>
+      <div style="font-size:1.35rem; font-weight:700;">{{ verify_result.last_chain_index }}</div>
+    </div>
+    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background:#fff;">
+      <div style="font-size:0.85rem; color:#64748b;">Mismatch Count</div>
+      <div style="font-size:1.35rem; font-weight:700;">{{ verify_result.mismatches|length }}</div>
+    </div>
+  </div>
+
+  {% if verify_result.mismatches %}
+  <div style="margin-bottom:20px; border:1px solid #fecaca; background:#fff7f7; border-radius:10px; padding:12px;">
+    <h3 style="margin-top:0; color:#991b1b;">Integritätsabweichungen</h3>
+    <div style="max-height:280px; overflow:auto;">
+      <table class="table" style="width:100%; border-collapse:collapse;">
+        <thead>
+          <tr>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Index</th>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Typ</th>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Expected</th>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Found</th>
+          </tr>
+        </thead>
+        <tbody>
+          {% for m in verify_result.mismatches %}
+          <tr>
+            <td style="padding:8px; border-bottom:1px solid #eee;">{{ m.chain_index }}</td>
+            <td style="padding:8px; border-bottom:1px solid #eee;">{{ m.error }}</td>
+            <td style="padding:8px; border-bottom:1px solid #eee; font-family:monospace;">{{ m.expected }}</td>
+            <td style="padding:8px; border-bottom:1px solid #eee; font-family:monospace;">{{ m.found }}</td>
+          </tr>
+          {% endfor %}
+        </tbody>
+      </table>
+    </div>
+  </div>
+  {% endif %}
+
+  <div style="border:1px solid #e2e8f0; border-radius:10px; background:#fff; padding:12px;">
+    <h3 style="margin-top:0;">Letzte Audit-Ereignisse</h3>
+    <div style="max-height:560px; overflow:auto;">
+      <table class="table" style="width:100%; border-collapse:collapse;">
+        <thead>
+          <tr>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Index</th>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Zeit</th>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Event</th>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Actor</th>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Hash</th>
+            <th style="text-align:left; padding:8px; border-bottom:1px solid #ddd;">Payload</th>
+          </tr>
+        </thead>
+        <tbody>
+          {% for row in audit_rows %}
+          <tr>
+            <td style="padding:8px; border-bottom:1px solid #eee;">{{ row.chain_index }}</td>
+            <td style="padding:8px; border-bottom:1px solid #eee;">{{ row.timestamp or row.created_at }}</td>
+            <td style="padding:8px; border-bottom:1px solid #eee;">{{ row.event_type }}</td>
+            <td style="padding:8px; border-bottom:1px solid #eee;">{{ row.actor }}</td>
+            <td style="padding:8px; border-bottom:1px solid #eee; font-family:monospace; font-size:0.8rem;">{{ row.entry_hash }}</td>
+            <td style="padding:8px; border-bottom:1px solid #eee;"><pre style="margin:0; white-space:pre-wrap; font-size:0.8rem;">{{ row.payload }}</pre></td>
+          </tr>
+          {% endfor %}
+        </tbody>
+      </table>
+    </div>
+  </div>
+</div>
+{% endblock %}

Web/templates/admin_borrowings.html

@@ -100,6 +100,9 @@
           {% if e.invoice_number %}
             <div style="font-weight:600;">{{ e.invoice_number }}</div>
             <div style="font-size:0.85rem; color:#666;">{{ e.invoice_amount }}</div>
+            {% if e.invoice_corrections_count %}
+              <div style="font-size:0.78rem; color:#7c2d12; margin-top:4px;">{{ e.invoice_corrections_count }} Korrektur(en)</div>
+            {% endif %}
             {% if e.invoice_paid %}
               <div style="display:inline-block; margin-top:6px; padding:2px 8px; border-radius:999px; background:#dcfce7; color:#166534; font-size:0.75rem; font-weight:700;">Bezahlt</div>
               {% if e.invoice_paid_at %}
@@ -129,6 +132,13 @@
               </button>
             </form>
             {% endif %}
+            {% if e.invoice_number %}
+            <form method="post" action="{{ url_for('admin_add_invoice_correction', borrow_id=e.id) }}" onsubmit="return confirm('Korrekturbuchung hinzufügen?');">
+              <input type="text" name="correction_reason" placeholder="Korrekturgrund" required style="padding:6px; border:1px solid #ddd; border-radius:6px; min-width:160px;">
+              <input type="text" name="amount_delta" placeholder="Delta (optional)" style="padding:6px; border:1px solid #ddd; border-radius:6px; width:120px;">
+              <button type="submit" class="btn btn-outline-danger">Korrektur</button>
+            </form>
+            {% endif %}
             <form method="post" action="{{ url_for('admin_reset_borrowing', borrow_id=e.id) }}" onsubmit="return confirm('Ausleihe zurücksetzen?');">
               <button type="submit" class="btn btn-warning">Zurücksetzen</button>
             </form>

Web/templates/admin_damaged_items.html

@@ -0,0 +1,121 @@
+{% extends "base.html" %}
+
+{% block title %}Defekte Items verwalten{% endblock %}
+
+{% block content %}
+<div class="container" style="max-width: 1250px; margin: 18px auto 32px;">
+  <div style="display:flex; justify-content:space-between; align-items:flex-start; gap:12px; flex-wrap:wrap; margin-bottom:16px;">
+    <div>
+      <h1 style="margin:0;">Defekte Items</h1>
+      <p style="margin:6px 0 0; color:#64748b;">Eigenes Verwaltungsfenster fuer gemeldete Defekte mit schneller Reparatur-Funktion.</p>
+    </div>
+    <div style="display:flex; gap:8px; flex-wrap:wrap;">
+      <a class="btn btn-outline-secondary" href="{{ url_for('admin_borrowings') }}">Ausleihen</a>
+      {% if library_module_enabled %}
+      <a class="btn btn-outline-secondary" href="{{ url_for('library_loans_admin') }}">Bibliothek</a>
+      {% endif %}
+    </div>
+  </div>
+
+  <div style="background:#fff; border:1px solid #e2e8f0; border-radius:14px; padding:14px; margin-bottom:12px;">
+    <input id="damage-search" type="text" placeholder="Suche nach Name, Code, Typ, Benutzer oder Schaden..." style="width:100%; padding:10px 12px; border:1px solid #d1d5db; border-radius:10px;">
+  </div>
+
+  <div style="background:#fff; border:1px solid #e2e8f0; border-radius:14px; padding:0; overflow:hidden;">
+    <table id="damage-table" style="width:100%; border-collapse:collapse;">
+      <thead>
+        <tr style="background:#f8fafc;">
+          <th style="text-align:left; padding:11px; border-bottom:1px solid #e5e7eb;">Item</th>
+          <th style="text-align:left; padding:11px; border-bottom:1px solid #e5e7eb;">Status</th>
+          <th style="text-align:left; padding:11px; border-bottom:1px solid #e5e7eb;">Letzte Meldung</th>
+          <th style="text-align:left; padding:11px; border-bottom:1px solid #e5e7eb;">Ausleihe</th>
+          <th style="text-align:left; padding:11px; border-bottom:1px solid #e5e7eb;">Aktion</th>
+        </tr>
+      </thead>
+      <tbody>
+        {% for item in damaged_items %}
+        <tr class="damage-row" data-search="{{ (item.name ~ ' ' ~ item.code ~ ' ' ~ item.item_type ~ ' ' ~ item.borrow_user ~ ' ' ~ item.latest_damage_description)|lower }}">
+          <td style="padding:11px; border-bottom:1px solid #eef2f7; vertical-align:top;">
+            <div style="font-weight:700;">{{ item.name }}</div>
+            <div style="font-size:0.86rem; color:#64748b;">{{ item.code or '-' }} | {{ item.item_type or '-' }}</div>
+            {% if item.author %}<div style="font-size:0.82rem; color:#64748b;">{{ item.author }}</div>{% endif %}
+            {% if item.isbn %}<div style="font-size:0.82rem; color:#64748b;">ISBN: {{ item.isbn }}</div>{% endif %}
+          </td>
+          <td style="padding:11px; border-bottom:1px solid #eef2f7; vertical-align:top;">
+            <div style="display:inline-block; padding:3px 9px; border-radius:999px; background:#fee2e2; color:#991b1b; font-size:0.75rem; font-weight:700;">Defekt</div>
+            <div style="font-size:0.84rem; color:#475569; margin-top:6px;">Meldungen: {{ item.damage_count }}</div>
+            <div style="font-size:0.84rem; color:#475569;">Condition: {{ item.condition or '-' }}</div>
+            <div style="font-size:0.84rem; color:#475569;">Verfuegbar: {{ 'Ja' if item.available else 'Nein' }}</div>
+          </td>
+          <td style="padding:11px; border-bottom:1px solid #eef2f7; vertical-align:top;">
+            <div style="font-size:0.9rem; color:#1f2937;">{{ item.latest_damage_description or '-' }}</div>
+            <div style="font-size:0.82rem; color:#64748b; margin-top:4px;">
+              Gemeldet von {{ item.latest_damage_by or '-' }}
+              {% if item.latest_damage_at %} am {{ item.latest_damage_at.strftime('%d.%m.%Y %H:%M') }}{% endif %}
+            </div>
+          </td>
+          <td style="padding:11px; border-bottom:1px solid #eef2f7; vertical-align:top;">
+            {% if item.active_borrow %}
+            <div style="display:inline-block; padding:3px 9px; border-radius:999px; background:#dbeafe; color:#1d4ed8; font-size:0.75rem; font-weight:700;">Aktiv/Geplant</div>
+            <div style="font-size:0.84rem; color:#475569; margin-top:6px;">User: {{ item.active_borrow.User or item.borrow_user or '-' }}</div>
+            {% if item.active_borrow.End %}
+            <div style="font-size:0.84rem; color:#475569;">Ende: {{ item.active_borrow.End.strftime('%d.%m.%Y %H:%M') }}</div>
+            {% endif %}
+            {% else %}
+            <div style="display:inline-block; padding:3px 9px; border-radius:999px; background:#dcfce7; color:#166534; font-size:0.75rem; font-weight:700;">Keine offene Ausleihe</div>
+            {% endif %}
+          </td>
+          <td style="padding:11px; border-bottom:1px solid #eef2f7; vertical-align:top;">
+            <button class="btn btn-success btn-sm" onclick="repairDamage('{{ item.id }}', this)">Als repariert markieren</button>
+          </td>
+        </tr>
+        {% endfor %}
+      </tbody>
+    </table>
+
+    {% if not damaged_items %}
+    <div style="padding:24px; color:#64748b; text-align:center;">Keine defekten Items vorhanden.</div>
+    {% endif %}
+  </div>
+</div>
+
+<script>
+(function() {
+  const searchInput = document.getElementById('damage-search');
+  if (searchInput) {
+    searchInput.addEventListener('input', function() {
+      const q = (searchInput.value || '').toLowerCase();
+      document.querySelectorAll('.damage-row').forEach(function(row) {
+        const text = row.getAttribute('data-search') || '';
+        row.style.display = text.includes(q) ? '' : 'none';
+      });
+    });
+  }
+})();
+
+function repairDamage(itemId, button) {
+  if (!itemId) return;
+  if (!confirm('Alle offenen Defektmeldungen fuer dieses Item als repariert markieren?')) {
+    return;
+  }
+
+  button.disabled = true;
+  fetch('/mark_damage_repaired/' + itemId, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({})
+  })
+    .then(function(res) { return res.json(); })
+    .then(function(data) {
+      if (!data.success) {
+        throw new Error(data.message || 'Reparatur fehlgeschlagen');
+      }
+      window.location.reload();
+    })
+    .catch(function(err) {
+      button.disabled = false;
+      alert(err.message || 'Fehler beim Markieren als repariert.');
+    });
+}
+</script>
+{% endblock %}

Web/templates/base.html

@@ -7,7 +7,7 @@
    For commercial licensing inquiries: https://github.com/AIIrondev
 -->
 <!DOCTYPE html>
-<html lang="en" data-module="inventory">
+<html lang="en" data-module="{{ CURRENT_MODULE }}">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=5.0, user-scalable=yes">
@@ -20,8 +20,8 @@
     <link rel="preconnect" href="https://fonts.googleapis.com">
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
     <link href="https://fonts.googleapis.com/css2?family=Manrope:wght@400;500;600;700;800&display=swap" rel="stylesheet">
-    <link rel="stylesheet" href="{{ url_for('static', filename='css/styles.css', v=APP_VERSION) }}">
+    <link rel="stylesheet" href="{{ url_for('static', filename='css/styles.css', v=ASSET_VERSION) }}">
-    <link rel="stylesheet" href="{{ url_for('static', filename='css/planned_appointments.css', v=APP_VERSION) }}">
+    <link rel="stylesheet" href="{{ url_for('static', filename='css/planned_appointments.css', v=ASSET_VERSION) }}">
     <link rel="icon" href="{{ url_for('static', filename='favicon.ico') }}">
     <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0-alpha1/dist/js/bootstrap.bundle.min.js"></script>
     <style>
@@ -369,7 +369,7 @@
         <span class="module-label">Module:</span>
         <div class="module-tabs">
             <a href="{{ url_for('home') }}" 
-               class="module-tab" 
+               class="module-tab {% if CURRENT_MODULE == 'inventory' %}active{% endif %}" 
                id="inventoryModule" 
                data-module="inventory">
                📦 Inventarsystem
@@ -377,7 +377,7 @@
             {% if library_module_enabled %}
             <div class="module-separator"></div>
             <a href="{{ url_for('library_view') }}" 
-               class="module-tab" 
+               class="module-tab {% if CURRENT_MODULE == 'library' %}active{% endif %}" 
                id="libraryModule" 
                data-module="library">
                📚 Bibliothek
@@ -386,48 +386,7 @@
         </div>
     </div>
     {% endif %}
-
+    {% if CURRENT_MODULE != 'library' %}
-    <script>
-        (function() {
-            // Detect current module based on URL and update data-module attribute
-            const currentPath = window.location.pathname;
-            const htmlTag = document.documentElement;
-            
-            // Detect module and pages
-            const isLibraryModule = currentPath.includes('/library') || 
-                                   currentPath.includes('/library_admin') ||
-                                   currentPath.includes('/library_loans') ||
-                                   currentPath.includes('/student_cards');
-            
-            const currentModule = isLibraryModule ? 'library' : 'inventory';
-            htmlTag.setAttribute('data-module', currentModule);
-            
-            // Update module selector tabs
-            const invModule = document.getElementById('inventoryModule');
-            const libModule = document.getElementById('libraryModule');
-
-            if (currentModule === 'library') {
-                if (libModule) libModule.classList.add('active');
-                if (invModule) invModule.classList.remove('active');
-            } else {
-                if (invModule) invModule.classList.add('active');
-                if (libModule) libModule.classList.remove('active');
-            }
-            
-            // Show/hide appropriate navbar based on current module
-            const invNavbar = document.getElementById('inventoryNavbar');
-            const libNavbar = document.getElementById('libraryNavbar');
-
-            if (currentModule === 'library') {
-                if (invNavbar) invNavbar.style.display = 'none';
-                if (libNavbar) libNavbar.style.display = '';
-            } else {
-                if (invNavbar) invNavbar.style.display = '';
-                if (libNavbar) libNavbar.style.display = 'none';
-            }
-        })();
-    </script>
-
     <nav class="navbar navbar-expand-lg navbar-dark" id="inventoryNavbar">
         <div class="container-fluid">
             <a class="navbar-brand" href="{{ url_for('home') }}" data-icon="📦">Inventarsystem</a>
@@ -459,6 +418,8 @@
                             <li><a class="dropdown-item" href="{{ url_for('manage_filters') }}">Filter verwalten</a></li>
                             <li><a class="dropdown-item" href="{{ url_for('manage_locations') }}">Orte verwalten</a></li>
                             <li><a class="dropdown-item" href="{{ url_for('admin_borrowings') }}">Ausleihen</a></li>
+                            <li><a class="dropdown-item" href="{{ url_for('admin_damaged_items') }}">Defekte Items</a></li>
+                            <li><a class="dropdown-item" href="{{ url_for('admin_audit_dashboard') }}">Audit Dashboard</a></li>
                             <li><a class="dropdown-item" href="{{ url_for('logs') }}">Logs</a></li>
                             <li><hr class="dropdown-divider"></li>
                             <li><h6 class="dropdown-header">System</h6></li>
@@ -475,11 +436,14 @@
                 <div class="d-flex">
                     {% if 'username' in session %}
                         <span class="navbar-text text-light me-3">{{ session['username'] }}</span>
-                        <div class="dropdown me-2">
+                        <div class="dropdown me-2 user-menu-wrap">
-                            <button class="btn btn-secondary dropdown-toggle" type="button" id="invUserMenuDropdown" data-bs-toggle="dropdown" aria-expanded="false">
+                            <button class="btn btn-secondary dropdown-toggle user-menu-btn" type="button" id="invUserMenuDropdown" data-bs-toggle="dropdown" aria-expanded="false" data-notification-button="true">
                                 👤
+                                <span class="user-notification-dot {% if unread_notification_count and unread_notification_count > 0 %}visible{% endif %}" aria-hidden="true"></span>
                             </button>
                             <ul class="dropdown-menu dropdown-menu-end" aria-labelledby="invUserMenuDropdown">
+                                <li><a class="dropdown-item" href="{{ url_for('notifications_view') }}">Benachrichtigungen</a></li>
+                                <li><hr class="dropdown-divider"></li>
                                 <li><a class="dropdown-item" href="{{ url_for('change_password') }}">Passwort ändern</a></li>
                                 <li><hr class="dropdown-divider"></li>
                                 <li><a class="dropdown-item" href="{{ url_for('logout') }}">Logout</a></li>
@@ -490,9 +454,10 @@
             </div>
         </div>
     </nav>
+    {% endif %}
 
-    {% if library_module_enabled %}
+    {% if library_module_enabled and CURRENT_MODULE == 'library' %}
-    <nav class="navbar navbar-expand-lg navbar-dark" id="libraryNavbar" style="display: none;">
+    <nav class="navbar navbar-expand-lg navbar-dark" id="libraryNavbar">
         <div class="container-fluid">
             <a class="navbar-brand" href="{{ url_for('library_view') }}" data-icon="📚">Bibliothek</a>
             <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#libraryNavContent">
@@ -521,8 +486,9 @@
                             {% if 'username' in session and (session.get('admin', False) or is_admin) %}
                             <li><h6 class="dropdown-header">Bibliotheks-Verwaltung</h6></li>
                             <li><a class="dropdown-item" href="{{ url_for('library_loans_admin') }}">Ausleihen</a></li>
+                            <li><a class="dropdown-item" href="{{ url_for('admin_damaged_items') }}">Defekte Items</a></li>
                             {% if student_cards_module_enabled %}
-                            <li><a class="dropdown-item" href="{{ url_for('student_cards_admin') }}">Schülerausweise</a></li>
+                            <li><a class="dropdown-item" href="{{ url_for('student_cards_admin') }}">Bibliotheksausweis</a></li>
                             {% endif %}
                             <li><hr class="dropdown-divider"></li>
                             <li><h6 class="dropdown-header">System</h6></li>
@@ -539,11 +505,14 @@
                 <div class="d-flex">
                     {% if 'username' in session %}
                         <span class="navbar-text text-light me-3">{{ session['username'] }}</span>
-                        <div class="dropdown me-2">
+                        <div class="dropdown me-2 user-menu-wrap">
-                            <button class="btn btn-secondary dropdown-toggle" type="button" id="libUserMenuDropdown" data-bs-toggle="dropdown" aria-expanded="false">
+                            <button class="btn btn-secondary dropdown-toggle user-menu-btn" type="button" id="libUserMenuDropdown" data-bs-toggle="dropdown" aria-expanded="false" data-notification-button="true">
                                 👤
+                                <span class="user-notification-dot {% if unread_notification_count and unread_notification_count > 0 %}visible{% endif %}" aria-hidden="true"></span>
                             </button>
                             <ul class="dropdown-menu dropdown-menu-end" aria-labelledby="libUserMenuDropdown">
+                                <li><a class="dropdown-item" href="{{ url_for('notifications_view') }}">Benachrichtigungen</a></li>
+                                <li><hr class="dropdown-divider"></li>
                                 <li><a class="dropdown-item" href="{{ url_for('change_password') }}">Passwort ändern</a></li>
                                 <li><hr class="dropdown-divider"></li>
                                 <li><a class="dropdown-item" href="{{ url_for('logout') }}">Logout</a></li>
@@ -555,23 +524,6 @@
         </div>
     </nav>
     {% endif %}
-
-    <script>
-        (function() {
-            // Show/hide appropriate navbar based on current module
-            const currentPath = window.location.pathname;
-            const invNavbar = document.getElementById('inventoryNavbar');
-            const libNavbar = document.getElementById('libraryNavbar');
-
-            if (currentPath.includes('/library')) {
-                if (invNavbar) invNavbar.style.display = 'none';
-                if (libNavbar) libNavbar.style.display = '';
-            } else {
-                if (invNavbar) invNavbar.style.display = '';
-                if (libNavbar) libNavbar.style.display = 'none';
-            }
-        })();
-    </script>
     <div class="container">
         {% with messages = get_flashed_messages(with_categories=true) %}
             {% if messages %}
@@ -653,6 +605,73 @@
             text-transform: uppercase;
             letter-spacing: 0.04em;
         }
+
+        .notif-badge {
+            display: inline-flex;
+            align-items: center;
+            justify-content: center;
+            min-width: 20px;
+            height: 20px;
+            border-radius: 999px;
+            background: #dc2626;
+            color: #fff;
+            font-size: 0.72rem;
+            font-weight: 800;
+            padding: 0 6px;
+            margin-left: 8px;
+            line-height: 1;
+        }
+
+        .user-menu-wrap {
+            position: relative;
+        }
+
+        .user-menu-btn {
+            position: relative;
+        }
+
+        .user-notification-dot {
+            position: absolute;
+            top: 6px;
+            right: 10px;
+            width: 10px;
+            height: 10px;
+            border-radius: 50%;
+            background: #2563eb;
+            border: 2px solid #ffffff;
+            box-shadow: 0 0 0 1px rgba(37, 99, 235, 0.35);
+            display: none;
+        }
+
+        .user-notification-dot.visible {
+            display: block;
+        }
+
+        .notification-toast {
+            position: fixed;
+            right: 16px;
+            bottom: 18px;
+            z-index: 2300;
+            max-width: 360px;
+            background: #0f172a;
+            color: #fff;
+            border-radius: 10px;
+            border: 1px solid rgba(148, 163, 184, 0.35);
+            box-shadow: 0 18px 35px rgba(2, 6, 23, 0.4);
+            padding: 12px 14px;
+            font-size: 0.9rem;
+            line-height: 1.35;
+            display: none;
+        }
+
+        .notification-toast strong {
+            display: block;
+            margin-bottom: 2px;
+        }
+
+        .notification-toast.show {
+            display: block;
+        }
     </style>
     <div id="cookie-banner" role="dialog" aria-live="polite" aria-label="Cookie-Hinweis">
         <div class="cb-inner">
@@ -680,6 +699,11 @@
         </div>
     </div>
 
+    <div id="notification-toast" class="notification-toast" role="status" aria-live="polite">
+        <strong id="notification-toast-title">Neue Benachrichtigung</strong>
+        <span id="notification-toast-message"></span>
+    </div>
+
     <script>
         (function(){
             function getCookie(name){
@@ -713,8 +737,111 @@
             const username = {{ (session['username'] if 'username' in session else '')|tojson }};
             const isTutorialPage = window.location.pathname === {{ url_for('tutorial_page')|tojson }};
             const isLoginPage = window.location.pathname === {{ url_for('login')|tojson }};
+            const notificationsPagePath = {{ url_for('notifications_view')|tojson }};
             const onboardingKey = username ? ('inventarsystem_tutorial_prompt_v1_' + username) : null;
             const onboardingOverlay = document.getElementById('onboarding-overlay');
+            const notificationButtons = Array.from(document.querySelectorAll('[data-notification-button="true"]'));
+            const notificationToast = document.getElementById('notification-toast');
+            const notificationToastTitle = document.getElementById('notification-toast-title');
+            const notificationToastMessage = document.getElementById('notification-toast-message');
+            let lastUnreadCount = Number({{ unread_notification_count|default(0)|int }});
+
+            function updateNotificationDots(unreadCount) {
+                const hasUnread = Number(unreadCount) > 0;
+                notificationButtons.forEach(function(btn) {
+                    const dot = btn.querySelector('.user-notification-dot');
+                    if (!dot) {
+                        return;
+                    }
+                    if (hasUnread) {
+                        dot.classList.add('visible');
+                    } else {
+                        dot.classList.remove('visible');
+                    }
+                });
+            }
+
+            function showInAppNotification(title, message) {
+                if (!notificationToast || !notificationToastTitle || !notificationToastMessage) {
+                    return;
+                }
+                notificationToastTitle.textContent = title || 'Neue Benachrichtigung';
+                notificationToastMessage.textContent = message || '';
+                notificationToast.classList.add('show');
+                window.setTimeout(function() {
+                    notificationToast.classList.remove('show');
+                }, 5000);
+            }
+
+            function showBrowserNotification(title, message) {
+                if (!('Notification' in window)) {
+                    showInAppNotification(title, message);
+                    return;
+                }
+                if (Notification.permission === 'granted') {
+                    new Notification(title || 'Neue Benachrichtigung', {
+                        body: message || '',
+                    });
+                    return;
+                }
+                if (Notification.permission === 'default') {
+                    Notification.requestPermission().then(function(permission) {
+                        if (permission === 'granted') {
+                            new Notification(title || 'Neue Benachrichtigung', {
+                                body: message || '',
+                            });
+                        } else {
+                            showInAppNotification(title, message);
+                        }
+                    }).catch(function() {
+                        showInAppNotification(title, message);
+                    });
+                    return;
+                }
+                showInAppNotification(title, message);
+            }
+
+            function pollNotificationStatus() {
+                if (!username) {
+                    return;
+                }
+
+                fetch('/notifications/unread_status', {
+                    method: 'GET',
+                    headers: {
+                        'Accept': 'application/json'
+                    }
+                })
+                    .then(function(response) {
+                        if (!response.ok) {
+                            throw new Error('status request failed');
+                        }
+                        return response.json();
+                    })
+                    .then(function(data) {
+                        if (!data || !data.ok) {
+                            return;
+                        }
+
+                        const unreadCount = Number(data.unread_count || 0);
+                        updateNotificationDots(unreadCount);
+
+                        if (unreadCount > lastUnreadCount && window.location.pathname !== notificationsPagePath) {
+                            const latest = data.latest_unread || {};
+                            showBrowserNotification(latest.title || 'Neue Nachricht', latest.message || 'Es gibt neue Benachrichtigungen.');
+                        }
+
+                        lastUnreadCount = unreadCount;
+                    })
+                    .catch(function() {
+                        // Silent fail; polling retries automatically.
+                    });
+            }
+
+            updateNotificationDots(lastUnreadCount);
+            if (username) {
+                window.setInterval(pollNotificationStatus, 30000);
+            }
 
             function showOnboarding(){
                 if (onboardingOverlay) {

Web/templates/library_borrowings_admin.html

@@ -282,6 +282,9 @@
             {% if e.invoice_number %}
               <div class="mono">{{ e.invoice_number }}</div>
               <div class="muted">{{ e.invoice_amount }}</div>
+              {% if e.invoice_corrections_count %}
+                <div class="muted" style="color:#7c2d12;">{{ e.invoice_corrections_count }} Korrektur(en)</div>
+              {% endif %}
               <div style="margin-top:6px;">
                 <a class="btn btn-outline-primary btn-sm" href="{{ url_for('admin_view_invoice_pdf', borrow_id=e.id) }}" target="_blank" rel="noopener">PDF öffnen</a>
               </div>
@@ -326,6 +329,14 @@
               </form>
               {% endif %}
 
+              {% if e.invoice_number %}
+              <form method="post" action="{{ url_for('admin_add_invoice_correction', borrow_id=e.id) }}" onsubmit="return confirm('Korrekturbuchung hinzufügen?');">
+                <input type="text" name="correction_reason" placeholder="Korrekturgrund" required style="padding:6px; border:1px solid #ddd; border-radius:6px; min-width:140px;">
+                <input type="text" name="amount_delta" placeholder="Delta optional" style="padding:6px; border:1px solid #ddd; border-radius:6px; width:120px;">
+                <button type="submit" class="btn btn-outline-danger btn-sm">Korrektur</button>
+              </form>
+              {% endif %}
+
               {% if e.status in ['active', 'planned'] %}
               <form method="post" action="{{ url_for('admin_reset_borrowing', borrow_id=e.id) }}" onsubmit="return confirm('Ausleihe zurücksetzen?');">
                 <button type="submit" class="btn btn-warning btn-sm">Zurücksetzen</button>

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');
+            const firstPage = await fetchLibraryPage(0, API_PAGE_SIZE);
-            if (!response.ok) throw new Error('Failed to load library items');
+            libraryItems = firstPage.items || [];
-            libraryItems = await response.json();
+            pagingState.offset = (firstPage.offset || 0) + (firstPage.count || libraryItems.length);
-            displayItems(libraryItems);
+            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
+    async function loadRemainingLibraryItemsInBackground() {
-    function displayItems(items) {
+        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();
+        activeFilters.author = document.getElementById('filterAuthor').value.toLowerCase();
-        const isbn = document.getElementById('filterISBN').value.toLowerCase();
+        activeFilters.isbn = document.getElementById('filterISBN').value.toLowerCase();
-        const type = document.getElementById('filterType').value;
+        activeFilters.type = document.getElementById('filterType').value;
-        const status = document.getElementById('filterStatus').value;
+        activeFilters.status = document.getElementById('filterStatus').value;
-
+        applyFiltersAndSearch(true);
-        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);
     });
 
     // 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();
+        currentSearchTerm = (e.target.value || '').toLowerCase();
-        const toSearch = filteredItems.length > 0 ? filteredItems : libraryItems;
+        applyFiltersAndSearch(true);
-        const results = toSearch.filter(item =>
+    });
-            (item.Name || '').toLowerCase().includes(searchTerm) ||
+
-            (item.Autor || item.Author || '').toLowerCase().includes(searchTerm) ||
+    document.getElementById('loadMoreBtn').addEventListener('click', () => {
-            (item.ISBN || item.Code4 || '').toLowerCase().includes(searchTerm)
+        renderedCount = Math.min(renderedCount + RENDER_BATCH_COUNT, visibleItems.length);
-        );
+        renderItems();
-        displayItems(results);
     });
 
     // Helper functions

Web/templates/main.html

@@ -724,8 +724,75 @@
     // Add this line to define allItems globally
     let allItems = [];
 
-    function loadItems() {
+    const MAIN_ITEMS_PAGE_SIZE = 120;
-        fetch("{{ url_for('get_items') }}")
+    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) {
+        // 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');
@@ -735,27 +802,39 @@
                 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 +1074,10 @@
                 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.
-                itemsContainer.scrollLeft = 0;
+                if (!append) {
+                    itemsContainer.scrollLeft = 0;
+                }
                 
                 // Apply filters
                 applyFilters();
@@ -1011,15 +1092,93 @@
                 if (activeFilters.filter1.length > 0 || activeFilters.filter2.length > 0) {
                     rebuildFilter3Options();
                 }
+
+                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;
+                }
                 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;
+
+        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;
@@ -1923,6 +2082,42 @@
         applyFilters();
     }
 
+    function bulkToggleFilterOptions(filterNum, shouldSelect) {
+        const filterKey = `filter${filterNum}`;
+        const checkboxes = Array.from(document.querySelectorAll(`#filter${filterNum}-options input[type="checkbox"]`));
+        if (checkboxes.length === 0) {
+            return;
+        }
+
+        const nextValues = new Set(activeFilters[filterKey]);
+
+        checkboxes.forEach(checkbox => {
+            const value = checkbox.value;
+            const group = checkbox.dataset.group || '';
+            const filterValue = group ? `${group}:${value}` : value;
+            checkbox.checked = shouldSelect;
+
+            if (shouldSelect) {
+                nextValues.add(filterValue);
+            } else {
+                nextValues.delete(filterValue);
+            }
+        });
+
+        activeFilters[filterKey] = Array.from(nextValues);
+        updateSelectedFilters(filterNum);
+
+        if (filterNum === 1) {
+            rebuildFilter2Options();
+            rebuildFilter3Options();
+        } else if (filterNum === 2) {
+            rebuildFilter3Options();
+        }
+
+        saveFilterState();
+        applyFilters();
+    }
+
     function populateFilterOptions(containerId, filterValues, filterNum) {
         const container = document.getElementById(containerId);
         if (!container) {
@@ -1932,6 +2127,27 @@
         
         container.innerHTML = ''; // Clear previous options
         
+        const bulkActions = document.createElement('div');
+        bulkActions.style.display = 'flex';
+        bulkActions.style.gap = '8px';
+        bulkActions.style.marginBottom = '10px';
+
+        const selectAllBtn = document.createElement('button');
+        selectAllBtn.type = 'button';
+        selectAllBtn.className = 'clear-filter';
+        selectAllBtn.textContent = 'Alle wählen';
+        selectAllBtn.onclick = () => bulkToggleFilterOptions(filterNum, true);
+
+        const clearAllBtn = document.createElement('button');
+        clearAllBtn.type = 'button';
+        clearAllBtn.className = 'clear-filter';
+        clearAllBtn.textContent = 'Alle abwählen';
+        clearAllBtn.onclick = () => bulkToggleFilterOptions(filterNum, false);
+
+        bulkActions.appendChild(selectAllBtn);
+        bulkActions.appendChild(clearAllBtn);
+        container.appendChild(bulkActions);
+
         // First group values by category/prefix if they exist
         const groupedValues = {};
         
@@ -2680,6 +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

@@ -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;
@@ -223,6 +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;
@@ -237,6 +388,12 @@
         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 +414,49 @@
         margin: 10px 0;
     }
 
+    .bulk-delete-row {
+        display: none;
+        justify-content: flex-start;
+        align-items: center;
+        margin-bottom: 8px;
+        gap: 8px;
+    }
+
+    .bulk-delete-mode-active .bulk-delete-row {
+        display: flex;
+    }
+
+    .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 +2309,26 @@ 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 +2709,8 @@ 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) }};
@@ -2802,9 +3021,9 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 if (parsedFilters.filter3) activeFilters.filter3 = parsedFilters.filter3;
                 
                 // Update UI to show selected filters
-                updateSelectedFilters(1);
+                updateSelectedFiltersDisplay(1);
-                updateSelectedFilters(2);
+                updateSelectedFiltersDisplay(2);
-                updateSelectedFilters(3);
+                updateSelectedFiltersDisplay(3);
                 
                 // We'll rebuild Filter 3 options after items are loaded
             } catch (e) {
@@ -2823,6 +3042,139 @@ document.addEventListener('DOMContentLoaded', ()=>{
         };
     }
 
+    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');
+        const itemsContainer = document.querySelector('#items-container');
+        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';
+        }
+        // Toggle checkbox visibility: show checkboxes only when bulk delete mode is active
+        if (itemsContainer) {
+            itemsContainer.classList.toggle('bulk-delete-mode-active', bulkDeleteDrawerOpen);
+        }
+    }
+
+    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 ${selectedIds.length} ausgewählte Elemente revisionssicher deaktivieren?`)) {
+            return;
+        }
+
+        fetch('{{ url_for('bulk_delete_items') }}', {
+            method: 'POST',
+            headers: {
+                'Content-Type': 'application/json',
+                'Accept': 'application/json'
+            },
+            body: JSON.stringify({ item_ids: selectedIds })
+        })
+        .then(async response => {
+            const data = await response.json().catch(() => ({}));
+            if (!response.ok || !data.success) {
+                throw new Error(data.message || 'Fehler beim Sammellöschen.');
+            }
+            clearBulkSelection();
+            alert(data.message || 'Auswahl gelöscht.');
+            loadItems();
+        })
+        .catch(error => {
+            alert(error.message || 'Fehler beim Sammellöschen.');
+        });
+    }
+    
     // Load predefined filter values for dropdowns
     function loadPredefinedFilterValues(filterNumber) {
         fetch(`/get_predefined_filter_values/${filterNumber}`)
@@ -2848,6 +3200,11 @@ document.addEventListener('DOMContentLoaded', ()=>{
                             select.removeChild(select.lastChild);
                         }
 
+                        const allOption = document.createElement('option');
+                        allOption.value = '__ALL__';
+                        allOption.textContent = '-- Alle auswählen --';
+                        select.appendChild(allOption);
+                        
                         // Add new options - data.values contains the array
                         data.values.forEach(filter => {
                             if (filter && filter.trim() !== '') {
@@ -2958,8 +3315,76 @@ document.addEventListener('DOMContentLoaded', ()=>{
     });
 
     // Function to load items from server
-    function loadItems() {
+    const MAIN_ADMIN_ITEMS_PAGE_SIZE = 120;
-        fetch("{{ url_for('get_items') }}")
+    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) {
+        // 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');
@@ -2969,9 +3394,13 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 const filter1Values = new Set();
                 const filter2Values = new Set();
                 const filter3Values = new Set();
-                allItems = data.items || [];
+                const pageItems = data.items || [];
-                itemsContainer.innerHTML = '';
+                allItems = append ? allItems.concat(pageItems) : pageItems;
-                if (!data.items || data.items.length === 0) {
+                totalItemsInSystem = Number(data.total || totalItemsInSystem || pageItems.length || 0);
+                if (!append) {
+                    itemsContainer.innerHTML = '';
+                }
+                if (!append && (!pageItems || pageItems.length === 0)) {
                     itemsContainer.innerHTML = `
                         <div class="no-items-message">
                             <div>Keine Objekte gefunden</div>
@@ -2984,15 +3413,25 @@ document.addEventListener('DOMContentLoaded', ()=>{
                     return;
                 }
                 if (itemsIndicator) {
-                    itemsIndicator.textContent = `Objekte im System: ${data.items.length}`;
+                    itemsIndicator.textContent = `Objekte im System: ${totalItemsInSystem}${data.has_more ? ' (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');
@@ -3143,6 +3582,12 @@ 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 ? `
@@ -3218,8 +3663,11 @@ 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();
@@ -3232,9 +3680,21 @@ document.addEventListener('DOMContentLoaded', ()=>{
                     rebuildFilter3Options();
                 }
                 /* favorites render count removed */
+
+                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;
+                }
                 const itemsContainer = document.querySelector('#items-container');
                 const itemsIndicator = document.getElementById('items-indicator');
                 itemsContainer.innerHTML = 
@@ -3245,6 +3705,67 @@ 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;
@@ -3339,7 +3860,7 @@ 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)) {
@@ -3528,7 +4049,11 @@ document.addEventListener('DOMContentLoaded', ()=>{
 
                 // Display existing images
                 const existingImagesContainer = document.getElementById('edit-existing-images');
+                const editForm = document.getElementById('edit-item-form');
                 existingImagesContainer.innerHTML = '';
+                if (editForm) {
+                    editForm.querySelectorAll('input[name="existing_images"], input[name="removed_images"]').forEach(input => input.remove());
+                }
                 if (item.Images && Array.isArray(item.Images)) {
                     item.Images.forEach((image, index) => {
                         const isVideo = isVideoFile(image);
@@ -3543,22 +4068,46 @@ document.addEventListener('DOMContentLoaded', ()=>{
                                 image : 
                                 `{{ url_for('uploaded_file', filename='') }}${image}`);
 
+                        const row = document.createElement('div');
+                        row.style.display = 'flex';
+                        row.style.gap = '8px';
+                        row.style.alignItems = 'center';
+
                         if (isVideo) {
-                            imageDiv.innerHTML = `
+                            const video = document.createElement('video');
-                                <div style="display:flex; gap:8px; align-items:center;">
+                            video.src = imageSrc;
-                                    <video src="${imageSrc}" style="max-width:100px; max-height:100px; object-fit:contain;" controls></video>
+                            video.style.maxWidth = '100px';
-                                    <button type="button" class="delete-image-button" onclick="deleteExistingImage('${item._id}', ${index})">Löschen</button>
+                            video.style.maxHeight = '100px';
-                                </div>
+                            video.style.objectFit = 'contain';
-                            `;
+                            video.controls = true;
+                            row.appendChild(video);
                         } else {
-                            imageDiv.innerHTML = `
+                            const img = document.createElement('img');
-                                <div style="display:flex; gap:8px; align-items:center;">
+                            img.src = imageSrc;
-                                    <img src="${imageSrc}" style="max-width:100px; max-height:100px; object-fit:contain;" alt="Existierendes Bild ${index + 1}">
+                            img.style.maxWidth = '100px';
-                                    <button type="button" class="delete-image-button" onclick="deleteExistingImage('${item._id}', ${index})">Löschen</button>
+                            img.style.maxHeight = '100px';
-                                </div>
+                            img.style.objectFit = 'contain';
-                            `;
+                            img.alt = `Existierendes Bild ${index + 1}`;
+                            row.appendChild(img);
                         }
+
+                        const deleteButton = document.createElement('button');
+                        deleteButton.type = 'button';
+                        deleteButton.className = 'delete-image-button';
+                        deleteButton.textContent = 'Löschen';
+                        deleteButton.addEventListener('click', () => removeExistingImage(image, deleteButton));
+                        row.appendChild(deleteButton);
+
+                        imageDiv.appendChild(row);
                         existingImagesContainer.appendChild(imageDiv);
+
+                        if (editForm) {
+                            const hiddenInput = document.createElement('input');
+                            hiddenInput.type = 'hidden';
+                            hiddenInput.name = 'existing_images';
+                            hiddenInput.value = image;
+                            editForm.appendChild(hiddenInput);
+                        }
                     });
                 }
 
@@ -4401,6 +4950,42 @@ document.addEventListener('DOMContentLoaded', ()=>{
         applyFilters();
     }
 
+    function bulkToggleFilterOptions(filterNum, shouldSelect) {
+        const filterKey = `filter${filterNum}`;
+        const checkboxes = Array.from(document.querySelectorAll(`#filter${filterNum}-options input[type="checkbox"]`));
+        if (checkboxes.length === 0) {
+            return;
+        }
+
+        const nextValues = new Set(activeFilters[filterKey]);
+
+        checkboxes.forEach(checkbox => {
+            const value = checkbox.value;
+            const group = checkbox.dataset.group || '';
+            const filterValue = group ? `${group}:${value}` : value;
+            checkbox.checked = shouldSelect;
+
+            if (shouldSelect) {
+                nextValues.add(filterValue);
+            } else {
+                nextValues.delete(filterValue);
+            }
+        });
+
+        activeFilters[filterKey] = Array.from(nextValues);
+        updateSelectedFiltersDisplay(filterNum);
+
+        if (filterNum === 1) {
+            rebuildFilter2Options();
+            rebuildFilter3Options();
+        } else if (filterNum === 2) {
+            rebuildFilter3Options();
+        }
+
+        saveFilterState();
+        applyFilters();
+    }
+
     function populateFilterOptions(containerId, filterValues, filterNum) {
         const container = document.getElementById(containerId);
         if (!container) {
@@ -4409,6 +4994,27 @@ document.addEventListener('DOMContentLoaded', ()=>{
         
         container.innerHTML = '';
 
+        const bulkActions = document.createElement('div');
+        bulkActions.style.display = 'flex';
+        bulkActions.style.gap = '8px';
+        bulkActions.style.marginBottom = '10px';
+
+        const selectAllBtn = document.createElement('button');
+        selectAllBtn.type = 'button';
+        selectAllBtn.className = 'clear-filter';
+        selectAllBtn.textContent = 'Alle wählen';
+        selectAllBtn.onclick = () => bulkToggleFilterOptions(filterNum, true);
+
+        const clearAllBtn = document.createElement('button');
+        clearAllBtn.type = 'button';
+        clearAllBtn.className = 'clear-filter';
+        clearAllBtn.textContent = 'Alle abwählen';
+        clearAllBtn.onclick = () => bulkToggleFilterOptions(filterNum, false);
+
+        bulkActions.appendChild(selectAllBtn);
+        bulkActions.appendChild(clearAllBtn);
+        container.appendChild(bulkActions);
+        
         const groupedValues = {};
         
         filterValues.forEach(value => {

Web/templates/notifications.html

@@ -0,0 +1,86 @@
+{% extends "base.html" %}
+
+{% block title %}Benachrichtigungen{% endblock %}
+
+{% block content %}
+<div class="container" style="max-width: 1080px; margin: 18px auto 32px;">
+  <div style="display:flex; justify-content:space-between; gap:12px; align-items:center; margin-bottom:16px; flex-wrap:wrap;">
+    <div>
+      <h1 style="margin:0;">Benachrichtigungen</h1>
+      <p style="margin:6px 0 0; color:#64748b;">Rueckgabe-Erinnerungen und wichtige Hinweise fuer Benutzer und Verwaltung.</p>
+    </div>
+    <form method="post" action="{{ url_for('mark_all_notifications_read') }}">
+      <button class="btn btn-outline-secondary" type="submit">Alle als gelesen markieren</button>
+    </form>
+  </div>
+
+  <div style="display:grid; grid-template-columns:1fr; gap:14px;">
+    <section style="background:#fff; border:1px solid #e2e8f0; border-radius:14px; padding:16px;">
+      <h2 style="margin:0 0 12px; font-size:1.15rem;">Meine Benachrichtigungen</h2>
+      {% if user_notifications %}
+      <div style="display:grid; gap:10px;">
+        {% for n in user_notifications %}
+        <article style="border:1px solid #e5e7eb; border-left:5px solid {% if n.severity == 'danger' %}#dc2626{% elif n.severity == 'warning' %}#d97706{% else %}#2563eb{% endif %}; border-radius:10px; padding:12px 12px 10px; background:{% if n.is_read %}#f8fafc{% else %}#ffffff{% endif %};">
+          <div style="display:flex; justify-content:space-between; gap:10px; align-items:flex-start; flex-wrap:wrap;">
+            <div>
+              <div style="font-weight:800; color:#0f172a;">{{ n.title }}</div>
+              <div style="font-size:0.9rem; color:#475569; margin-top:2px;">{{ n.message }}</div>
+              {% if n.type == 'damage_reported' %}
+              <div style="margin-top:8px;">
+                <a class="btn btn-sm btn-outline-danger" href="{{ url_for('admin_damaged_items') }}">Zu Defekte-Items Verwaltung</a>
+              </div>
+              {% endif %}
+              <div style="font-size:0.78rem; color:#64748b; margin-top:6px;">
+                {% if n.created_at %}{{ n.created_at.strftime('%d.%m.%Y %H:%M') }}{% else %}-{% endif %}
+              </div>
+            </div>
+            {% if not n.is_read %}
+            <form method="post" action="{{ url_for('mark_notification_read', notification_id=n.id) }}">
+              <button class="btn btn-sm btn-primary" type="submit">Als gelesen</button>
+            </form>
+            {% else %}
+            <span style="font-size:0.8rem; color:#16a34a; font-weight:700;">Gelesen</span>
+            {% endif %}
+          </div>
+        </article>
+        {% endfor %}
+      </div>
+      {% else %}
+      <p style="color:#64748b; margin:0;">Keine Benachrichtigungen vorhanden.</p>
+      {% endif %}
+    </section>
+
+    {% if is_admin_user %}
+    <section style="background:#fff; border:1px solid #e2e8f0; border-radius:14px; padding:16px;">
+      <h2 style="margin:0 0 12px; font-size:1.15rem;">Admin-Benachrichtigungen</h2>
+      {% if admin_notifications %}
+      <div style="display:grid; gap:10px;">
+        {% for n in admin_notifications %}
+        <article style="border:1px solid #e5e7eb; border-left:5px solid {% if n.severity == 'danger' %}#dc2626{% elif n.severity == 'warning' %}#d97706{% else %}#2563eb{% endif %}; border-radius:10px; padding:12px 12px 10px; background:{% if n.is_read %}#f8fafc{% else %}#ffffff{% endif %};">
+          <div style="display:flex; justify-content:space-between; gap:10px; align-items:flex-start; flex-wrap:wrap;">
+            <div>
+              <div style="font-weight:800; color:#0f172a;">{{ n.title }}</div>
+              <div style="font-size:0.9rem; color:#475569; margin-top:2px;">{{ n.message }}</div>
+              <div style="font-size:0.78rem; color:#64748b; margin-top:6px;">
+                {% if n.created_at %}{{ n.created_at.strftime('%d.%m.%Y %H:%M') }}{% else %}-{% endif %}
+              </div>
+            </div>
+            {% if not n.is_read %}
+            <form method="post" action="{{ url_for('mark_notification_read', notification_id=n.id) }}">
+              <button class="btn btn-sm btn-primary" type="submit">Als gelesen</button>
+            </form>
+            {% else %}
+            <span style="font-size:0.8rem; color:#16a34a; font-weight:700;">Gelesen</span>
+            {% endif %}
+          </div>
+        </article>
+        {% endfor %}
+      </div>
+      {% else %}
+      <p style="color:#64748b; margin:0;">Keine Admin-Benachrichtigungen vorhanden.</p>
+      {% endif %}
+    </section>
+    {% endif %}
+  </div>
+</div>
+{% endblock %}

Web/templates/student_card_barcode_print.html

@@ -124,12 +124,12 @@
     <div class="container">
         <div class="icon">📇</div>
         <h1>Schülerausweis-Download</h1>
-        <p>Generieren Sie eine PDF mit Barcodes aller Schülerausweise zum direkten Drucken</p>
+        <p>Generieren Sie eine PDF mit Barcodes aller Bibliotheksausweise zum direkten Drucken</p>
 
         <div class="info-box">
             <strong>📌 Was wird heruntergeladen?</strong>
             <p>Eine druckfertige PDF mit:</p>
-            <p>✓ Alle Schülerausweise</p>
+            <p>✓ Alle Bibliotheksausweise</p>
             <p>✓ Scanbare CODE128 Barcodes</p>
             <p>✓ Optimiert für A4-Druck (2 Karten pro Seite)</p>
             <p>✓ Professionelle Qualität</p>

Web/templates/student_cards_admin.html

@@ -8,7 +8,7 @@
 -->
 {% extends "base.html" %}
 
-{% block title %}Schülerausweise - Inventarsystem{% endblock %}
+{% block title %}Bibliotheksausweise - Inventarsystem{% endblock %}
 
 {% block content %}
 <style>
@@ -229,7 +229,7 @@
 <div class="container">
     <div class="student-card-header">
         <div>
-            <h1>📚 Schülerausweise (Bibliotek)</h1>
+            <h1>📚 Bibliotheksausweise (Bibliotek)</h1>
         </div>
         <div class="export-buttons">
             <a href="{{ url_for('student_card_barcode_download') }}" class="btn-print" style="background: #28a745;">📥 Alle Ausweise (PDF)</a>
@@ -342,7 +342,7 @@
             </table>
         {% else %}
             <div class="empty-state">
-                <p>Keine Schülerausweise registriert.</p>
+                <p>Keine Bibliotheksausweise registriert.</p>
                 <p>Fügen Sie ein neues Ausweis oben hinzu.</p>
             </div>
         {% endif %}

Web/templates/upload_admin.html

@@ -711,6 +711,28 @@
 <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>
         <form method="POST" action="{{ url_for('upload_item') }}" enctype="multipart/form-data">
@@ -1115,8 +1137,16 @@
                             select.removeChild(select.lastChild);
                         }
 
+                        const allOption = document.createElement('option');
+                        allOption.value = '__ALL__';
+                        allOption.textContent = '-- Alle auswählen --';
+                        select.appendChild(allOption);
+                        
                         // Add new options - data.values contains the array
                         data.values.forEach(value => {
+                            if (!value || String(value).trim() === '') {
+                                return;
+                            }
                             const option = document.createElement('option');
                             option.value = value;
                             option.textContent = value;

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):

Web/verify_audit_chain.py

@@ -0,0 +1,31 @@
+#!/usr/bin/env python3
+"""CLI utility to verify the tamper-evident audit chain."""
+
+import json
+import sys
+
+from pymongo import MongoClient
+
+import settings as cfg
+import audit_log as al
+
+
+def main():
+    client = None
+    try:
+        client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
+        db = client[cfg.MONGODB_DB]
+        al.ensure_audit_indexes(db)
+        result = al.verify_audit_chain(db)
+        print(json.dumps(result, ensure_ascii=False, indent=2, default=str))
+        return 0 if result.get("ok") else 2
+    except Exception as exc:
+        print(json.dumps({"ok": False, "error": str(exc)}, ensure_ascii=False))
+        return 1
+    finally:
+        if client:
+            client.close()
+
+
+if __name__ == "__main__":
+    sys.exit(main())

docker-compose.yml

@@ -42,6 +42,7 @@ services:
     expose:
       - "8000"
     volumes:
+      - ./config.json:/app/config.json:ro
       - ./Web:/app/Web
       - app_uploads:/app/Web/uploads
       - app_thumbnails:/app/Web/thumbnails

requirements.txt

@@ -10,3 +10,4 @@ pytz
 requests
 reportlab
 python-barcode
+openpyxl

start.sh

@@ -290,6 +290,44 @@ EOF
     fi
 }
 
+ensure_runtime_config_json() {
+        local config_path backup_path
+        config_path="$SCRIPT_DIR/config.json"
+
+        if [ -d "$config_path" ]; then
+                backup_path="${config_path}.dir.$(date +%Y%m%d-%H%M%S).bak"
+                mv "$config_path" "$backup_path"
+                echo "Warning: moved unexpected directory $config_path to $backup_path"
+        fi
+
+        if [ ! -f "$config_path" ]; then
+                cat > "$config_path" <<'EOF'
+{
+    "ver": "2.6.5",
+    "dbg": false,
+    "host": "0.0.0.0",
+    "port": 443,
+    "mongodb": {
+        "host": "mongodb",
+        "port": 27017,
+        "db": "Inventarsystem"
+    },
+    "modules": {
+        "library": {
+            "enabled": false
+        },
+        "student_cards": {
+            "enabled": false,
+            "default_borrow_days": 14,
+            "max_borrow_days": 365
+        }
+    }
+}
+EOF
+                echo "Created default runtime config at $config_path"
+        fi
+}
+
 ensure_app_image_loaded() {
     if docker image inspect "$APP_IMAGE_VALUE" >/dev/null 2>&1; then
         return 0
@@ -558,6 +596,7 @@ ensure_runtime_dependencies
 setup_boot_autostart_service
 ensure_tls_certificates
 ensure_nginx_config_mount_source
+ensure_runtime_config_json
 setup_scheduled_jobs
 configure_nuitka_mode
 resolve_app_image

update.sh

@@ -234,10 +234,26 @@ load_release_image() {
     log_message "Loading app image from release asset $image_asset"
     curl -fL "$image_url" -o "$archive"
     docker load -i "$archive" >> "$LOG_FILE" 2>&1
+    docker tag "$APP_IMAGE_REPO:$tag" "$APP_IMAGE_REPO:latest" >> "$LOG_FILE" 2>&1 || true
 
     trap - RETURN
 }
 
+refresh_runtime_scripts_from_main() {
+    local start_url stop_url restart_url update_url
+    start_url="https://raw.githubusercontent.com/$REPO_SLUG/main/start.sh"
+    stop_url="https://raw.githubusercontent.com/$REPO_SLUG/main/stop.sh"
+    restart_url="https://raw.githubusercontent.com/$REPO_SLUG/main/restart.sh"
+    update_url="https://raw.githubusercontent.com/$REPO_SLUG/main/update.sh"
+
+    curl -fsSL "$start_url" -o "$PROJECT_DIR/start.sh" || log_message "WARNING: Could not refresh start.sh from main"
+    curl -fsSL "$stop_url" -o "$PROJECT_DIR/stop.sh" || log_message "WARNING: Could not refresh stop.sh from main"
+    curl -fsSL "$restart_url" -o "$PROJECT_DIR/restart.sh" || log_message "WARNING: Could not refresh restart.sh from main"
+    curl -fsSL "$update_url" -o "$PROJECT_DIR/update.sh" || log_message "WARNING: Could not refresh update.sh from main"
+
+    chmod +x "$PROJECT_DIR/start.sh" "$PROJECT_DIR/stop.sh" "$PROJECT_DIR/restart.sh" "$PROJECT_DIR/update.sh"
+}
+
 find_local_dist_image_archive() {
     local tag="$1"
     local archive
@@ -277,6 +293,7 @@ load_local_dist_image() {
 
     log_message "Loading app image from local dist artifact: $archive"
     if docker load -i "$archive" >> "$LOG_FILE" 2>&1; then
+        docker tag "$APP_IMAGE_REPO:$tag" "$APP_IMAGE_REPO:latest" >> "$LOG_FILE" 2>&1 || true
         return 0
     fi
 
@@ -308,6 +325,11 @@ download_and_extract_bundle() {
         cp -f "$tmp_dir/update.sh" "$PROJECT_DIR/update.sh"
     fi
 
+    if [ ! -f "$PROJECT_DIR/config.json" ] && [ -f "$tmp_dir/config.json" ]; then
+        cp -f "$tmp_dir/config.json" "$PROJECT_DIR/config.json"
+        log_message "Installed default config.json from release bundle"
+    fi
+
     chmod +x "$PROJECT_DIR/start.sh" "$PROJECT_DIR/stop.sh" "$PROJECT_DIR/restart.sh" "$PROJECT_DIR/update.sh" "$PROJECT_DIR/backup.sh"
 }
 
@@ -342,6 +364,7 @@ EOF
 
     docker compose --env-file "$ENV_FILE" pull nginx mongodb >> "$LOG_FILE" 2>&1
     docker compose --env-file "$ENV_FILE" up -d --remove-orphans >> "$LOG_FILE" 2>&1
+    docker tag "$app_image" "$APP_IMAGE_REPO:latest" >> "$LOG_FILE" 2>&1 || true
 }
 
 verify_stack_health() {
@@ -460,6 +483,7 @@ main() {
 
     log_message "Updating from release $latest_tag"
     download_and_extract_bundle "$bundle_url" "$tmp_dir"
+    refresh_runtime_scripts_from_main
     deploy "$latest_tag" "$meta_file"
     if ! verify_stack_health; then
         log_message "ERROR: Updated stack failed health check"