Implementation of encryption for sensitive information that may be providet by the client, to ensure that all information important or not is safe

Web/app.py

@@ -3302,7 +3302,13 @@ def api_library_items():
                 borrower = doc.get('User', '')
             # Decrypt if value is encrypted (decrypt_text returns original if not encrypted)
             try:
-                borrower = decrypt_text(borrower) if borrower else ''
+                client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
+                db = client[cfg.MONGODB_DB]
+                student_cards = db['student_cards']
+                card = student_cards.find_one({'_id': ObjectId(borrow_id)})
+                card = _decrypt_student_card_doc(card)
+                client.close()
+                borrower = card['SchülerName']
             except Exception:
                 # Fallback: keep original string if decryption fails
                 borrower = borrower or ''
@@ -3821,7 +3827,7 @@ def library_admin():
         show_library_features=True,
         upload_mode='library',
         page_title='Bücher hochladen',
-        back_target='home_admin'
+        back_target='library'
     )
 
 
@@ -5074,7 +5080,7 @@ def upload_item():
     Enhanced for mobile browser compatibility.
     
     Returns:
-        flask.Response: Redirect to admin homepage or JSON response
+        flask.Response: Redirect to admin homepage
     """
     # Check if the user is authenticated
     if 'username' not in session:
@@ -5087,7 +5093,12 @@ def upload_item():
         return jsonify({'success': False, 'message': 'Einfüge-Rechte erforderlich'}), 403
         
     can_access_admin_home = _page_access_allowed(permissions, 'home_admin') and _action_access_allowed(permissions, 'can_manage_settings')
-    success_redirect_endpoint = 'home_admin' if can_access_admin_home else 'home'
+    if can_access_admin_home:
+        success_redirect_endpoint = 'home_admin'
+    elif cfg.MODULES.is_enabled('library') and _page_access_allowed(permissions, 'home_library'):
+        success_redirect_endpoint = 'home_library'
+    else:
+        success_redirect_endpoint = 'home'
 
     # Detect if request is from mobile device
     is_mobile = 'Mobile' in request.headers.get('User-Agent', '')
@@ -6044,22 +6055,9 @@ def upload_item():
             except Exception:
                 app.logger.warning('Audit write failed for library_item_created')
 
-        if is_mobile:
-            return jsonify({
-                'success': True, 
-                'message': success_msg,
-                'itemId': str(item_id),
-                'stats': {
-                    'processed': processed_count,
-                    'errors': error_count,
-                    'skipped': skipped_count,
-                    'duplicates': len(duplicate_images) if duplicate_images else 0,
-                    'totalImages': len(image_filenames)
-                }
-            })
-        else:
-            flash(success_msg, 'success')
-            return redirect(url_for(success_redirect_endpoint, highlight_item=str(item_id)))
+        
+        flash(success_msg, 'success')
+        return redirect(url_for(success_redirect_endpoint, highlight_item=str(item_id)))
     else:
         error_msg = 'Fehler beim Hinzufügen des Elements'
         if is_mobile:
@@ -8376,8 +8374,15 @@ def admin_create_invoice(borrow_id):
             flash('Für diese Ausleihe existiert bereits eine Rechnung. Bitte Korrekturbuchung verwenden.', 'warning')
             return redirect(url_for('admin_borrowings'))
 
+        client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
+        db = client[cfg.MONGODB_DB]
+        student_cards = db['student_cards']
+        card = student_cards.find_one({'_id': ObjectId(borrow_id)})
+        card = _decrypt_student_card_doc(card)
+        client.close()
+        borrower = card['SchülerName']
+
         invoice_number = existing_invoice.get('invoice_number') or _build_invoice_number(borrow_doc['_id'], now)
-        borrower = borrow_doc.get('User', '')
         item_name = item_doc.get('Name', '')
         item_code = item_doc.get('Code_4', '')
 

Web/modules/database/termine.py

@@ -18,9 +18,11 @@ Collection Structure:
   - Status fields: slots_used_by
 """
 import Web.modules.database.settings as cfg
+import Web.modules.inventarsystem.data_protection as dp
 from Web.modules.database.settings import MongoClient
 from bson.objectid import ObjectId
 import datetime 
+import ast
 
 
 def _get_tenant_db(client):
@@ -37,8 +39,47 @@ def _active_record_query(extra_query=None):
         base_query.update(extra_query)
     return base_query
 
+def _decrypt_appointment(item):
+    """Helper function to safely decrypt appointment fields back to their original types."""
+    if not item:
+        return item
+    
+    try:
+        if 'user' in item and item['user']:
+            item['user'] = dp.decrypt_text(item['user'])
+        
+        if 'note' in item and item['note']:
+            item['note'] = dp.decrypt_text(item['note'])
+            
+        if 'title' in item and item['title']:
+            item['title'] = dp.decrypt_text(item['title'])
+            
+        if 'mail' in item and item['mail']:
+            decrypted_mail = dp.decrypt_text(item['mail'])
+            try:
+                item['mail'] = ast.literal_eval(decrypted_mail)
+            except Exception:
+                item['mail'] = decrypted_mail
 
-def add(date_start: str, date_end: str, time_span: list, slots: int, slot_lenght: int, user: str, mail: list=[], note:str="", calendar_enabled: bool=False, title: str=""):
+        if 'custom_fields' in item and item['custom_fields']:
+            item['custom_fields'] = [dp.decrypt_text(field) for field in item['custom_fields']]
+
+        if 'slots_booked' in item and item['slots_booked']:
+            # If it's a string, it was encrypted during an update execution
+            if isinstance(item['slots_booked'], str):
+                decrypted_slots = dp.decrypt_text(item['slots_booked'])
+                try:
+                    item['slots_booked'] = ast.literal_eval(decrypted_slots)
+                except Exception:
+                    item['slots_booked'] = decrypted_slots
+    except Exception as e:
+        print(f"Error during decryption: {e}")
+        
+    return item
+
+
+def add(date_start: str, date_end: str, time_span: list, slots: int, slot_lenght: int, user: str, mail: list=[], note:str="", calendar_enabled: bool=False, title: str="", custom_fields: list = (), clients_p_slot: int=1):
+    client = None
     try:
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = _get_tenant_db(client)
@@ -50,60 +91,53 @@ def add(date_start: str, date_end: str, time_span: list, slots: int, slot_lenght
             'time_span': time_span,
             'slots': slots,
             'slot_lenght': slot_lenght,
-            'user': user,
-            'mail': mail,
-            'note': note,
-            'title': title,
+            'user': dp.encrypt_text(user.strip()),
+            'mail': dp.encrypt_text(str(mail)),
+            'note': dp.encrypt_text(note),
+            'title': dp.encrypt_text(title),
+            'custom_fields': [dp.encrypt_text(str(field)) for field in custom_fields],
             'calendar_enabled': bool(calendar_enabled),
-            'slots_booked': [], # -> [(start_time, name), ...]the list gets there indexes as the slot 1-defined so is can be counted without an extra variable
+            'clients_per_slot': clients_p_slot,
+            'slots_booked': [],  # -> [(start_time, (names),(custom1, custom2,...)), ...]the list gets there indexes as the slot 1-defined so is can be counted without an extra variable
             'Created': datetime.datetime.now(),
             'LastUpdated': datetime.datetime.now()
         }
         result = items.insert_one(item)
         return result.inserted_id
     except Exception as e:
-        print(f"Exception accured: {e}")
-
+        print(f"Exception occurred in add: {e}")
+        return None
+    finally:
+        if client:
+            client.close()
 
 def get_item(id):
-    """
-    Retrieve a specific appointment by its ID.
-    
-    Args:
-        id (str): ID of the appointsment to retrieve
-        
-    Returns:
-        dict: The appointment document or None if not found
-    """
+    """Retrieve a specific appointment by its ID and decrypt it."""
+    client = None
     try:
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = _get_tenant_db(client)
         items = db['appointments']
         item = items.find_one(_active_record_query({'_id': ObjectId(id)}))
-        client.close()
-        return item
+        
+        return _decrypt_appointment(item)
     except Exception as e:
         print(f"Error retrieving item: {e}")
         return None
+    finally:
+        if client:
+            client.close()
 
-def update(id,slots_used: list):
-    """
-    Update an existing appointment.
-    
-    Args:
-        id (str): ID of the item to update
-        
-        
-    Returns:
-        bool: True if successful, False otherwise
-    """
+def update(id, slots_used: list):
+    """Update an existing appointment's booked slots securely."""
+    client = None
     try:
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = _get_tenant_db(client)
         items = db['appointments']
 
         update_data = {
-            'slots_booked': slots_used,
+            'slots_booked': dp.encrypt_text(str(slots_used)),
             'LastUpdated': datetime.datetime.now()
         }
 
@@ -112,53 +146,81 @@ def update(id,slots_used: list):
             {'$set': update_data}
         )
 
-        client.close()
         return result.modified_count > 0
     except Exception as e:
         print(f"Error updating item: {e}")
         return False
-
+    finally:
+        if client:
+            client.close()
 
 def remove_slot(id, date_start_time, name):
     """
-    Remove a booked slot from an appointment's `slots_booked`.
-
-    Args:
-        id (str): Appointment ID
-        date_start_time: The start time value used when booking
-        name (str): Name associated with the booking
-
-    Returns:
-        bool: True if a slot was removed, False otherwise
+    Remove a booked slot from an appointment's encrypted `slots_booked` list.
+    
+    Because the array is stored as an encrypted string blob, we must decrypt, 
+    modify it in Python, and re-encrypt it.
     """
+    client = None
     try:
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = _get_tenant_db(client)
         items = db['appointments']
 
-        # Attempt to pull the exact element (stored as an array/tuple)
+        item = items.find_one({'_id': ObjectId(id)})
+        if not item or 'slots_booked' not in item or not item['slots_booked']:
+            return False
+
+        try:
+            decrypted_slots = dp.decrypt_text(item['slots_booked'])
+            slots_list = ast.literal_eval(decrypted_slots)
+        except Exception as e:
+            print(f"Failed to decrypt or parse slots: {e}")
+            return False
+
+        # Structure format note: [(start_time, (names), (custom1, custom2...)), ...]
+        updated_slots = []
+        removed_any = False
+        
+        for slot in slots_list:
+            slot_start = slot[0]
+            slot_names = slot[1]
+            
+
+            if slot_start == date_start_time and (slot_names == name or name in slot_names):
+                removed_any = True
+                continue 
+            updated_slots.append(slot)
+
+        if not removed_any:
+            return False 
+
         result = items.update_one(
             {'_id': ObjectId(id)},
-            {'$pull': {'slots_booked': [date_start_time, name]}}
+            {
+                '$set': {
+                    'slots_booked': dp.encrypt_text(str(updated_slots)),
+                    'LastUpdated': datetime.datetime.now()
+                }
+            }
         )
 
-        client.close()
         return result.modified_count > 0
     except Exception as e:
         print(f"Error removing slot: {e}")
         return False
+    finally:
+        if client:
+            client.close()
 
 
 def remove(id):
     """
-    Soft-delete an appointment by setting its `Deleted` flag.
-
-    Args:
-        id (str): Appointment ID
-
-    Returns:
-        bool: True if the appointment was marked deleted, False otherwise
+    Hard-delete an appointment plan by its ID.
+    (Note: If your docstring mentions a soft-delete 'Deleted' flag, 
+    change items.delete_one to items.update_one with {'$set': {'Deleted': True}})
     """
+    client = None
     try:
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = _get_tenant_db(client)
@@ -166,54 +228,64 @@ def remove(id):
 
         result = items.delete_one({'_id': ObjectId(id)})
 
-        client.close()
         return result.deleted_count > 0
     except Exception as e:
         print(f"Error removing appointment: {e}")
         return False
+    finally:
+        if client:
+            client.close()
+
 
 def remove_done():
-    """removose already finisched appointments"""
+    """Remove all expired appointments whose end date is prior to today in a single call."""
+    client = None
     try:
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = _get_tenant_db(client)
         items = db['appointments']
 
         today = datetime.date.today().strftime('%Y-%m-%d')
-        removed_count = 0
 
-        cursor = items.find(
+        result = items.delete_many(
             _active_record_query(
                 {
                     'date_end': {'$lt': today},
                 }
             )
-        ).sort('date_start', 1)
+        )
 
-        for item in cursor:
-            item['_id'] = str(item.get('_id'))
-            result = items.delete_one({'_id': ObjectId(item['_id'])})
-            removed_count += result.deleted_count
-        
-        client.close()
-        return removed_count > 0
+        return result.deleted_count > 0
     except Exception as e:
-        print(f"Error removing appointment: {e}")
+        print(f"Error cleaning up finished appointments: {e}")
         return False
+    finally:
+        if client:
+            client.close()
+
 
 def get_upcoming_for_user(user: str, limit: int = 25):
-    """Return upcoming appointment plans for a user ordered by start date."""
-    remove_done()
+    """Return upcoming appointment plans for a user, matching by encrypted username."""
+    try:
+        if hasattr(globals(), 'remove_done'):
+            remove_done()
+    except Exception:
+        pass
+
+    client = None
     try:
         client = MongoClient(cfg.MONGODB_HOST, cfg.MONGODB_PORT)
         db = _get_tenant_db(client)
         items = db['appointments']
 
         today = datetime.date.today().strftime('%Y-%m-%d')
+        
+        encrypted_user = dp.encrypt_text(str(user or '').strip())
+
         cursor = items.find(
             _active_record_query(
                 {
-                    'user': str(user or '').strip(),
+                    'user': encrypted_user,
                     'date_end': {'$gte': today},
                 }
             )
@@ -222,14 +294,14 @@ def get_upcoming_for_user(user: str, limit: int = 25):
         results = []
         for item in cursor:
             item['_id'] = str(item.get('_id'))
-            results.append(item)
+            results.append(_decrypt_appointment(item))
             if len(results) >= max(1, int(limit)):
                 break
 
-        client.close()
         return results
     except Exception as e:
         print(f"Error retrieving upcoming appointments: {e}")
         return []
-
- 
+    finally:
+        if client:
+            client.close()

Web/modules/terminplaner/backend_server.py

@@ -8,6 +8,7 @@ import Web.modules.emailservice.email as mail_service
 import Web.modules.database.termine as termin
 import Web.modules.database.settings as cfg
 from Web.tenant import get_tenant_context
+import Web.modules.inventarsystem.data_protection as dp
 
 
 def _resolve_public_base_url() -> str:
@@ -99,8 +100,11 @@ def build_calendar_ics(appointment_id: str) -> str | None:
         return None
 
     uid = f"terminplaner-{appointment_id}@invario.eu"
-    created_at = datetime.datetime.utcnow().strftime('%Y%m%dT%H%M%SZ')
-    summary = f"Terminplan für {creator}"
+    
+    created_at = datetime.datetime.now(datetime.timezone.utc).strftime('%Y%m%dT%H%M%SZ')
+    
+    summary = titel if titel else f"Terminplan für {creator}"
+    
     description_lines = [
         f"Buchungslink: {link}",
         f"Zeitraum: {date_start} bis {date_end}",
@@ -109,7 +113,7 @@ def build_calendar_ics(appointment_id: str) -> str | None:
         description_lines.append('Zeitfenster: ' + '; '.join(str(entry) for entry in time_span))
     if note:
         description_lines.append('Notiz: ' + str(note))
-    if titel:
+    if titel and not summary == titel: 
         description_lines.append('Titel: ' + str(titel))
 
     ics_lines = [
@@ -125,8 +129,7 @@ def build_calendar_ics(appointment_id: str) -> str | None:
         f'DESCRIPTION:{_escape_ics_text(chr(10).join(description_lines))}',
         f'URL:{_escape_ics_text(link)}',
         f'DTSTART;VALUE=DATE:{_format_ics_date(start_date)}',
-        f'DTEND;VALUE=DATE:{_format_ics_date(end_date + timedelta(days=1))}',
-        f'Titel:{_escape_ics_text(titel)}',
+        f'DTEND;VALUE=DATE:{_format_ics_date(end_date + datetime.timedelta(days=1))}',
         'END:VEVENT',
         'END:VCALENDAR',
         '',
@@ -172,7 +175,7 @@ def build_client_slot_ics(appointment_id: str, slot_start: str, client_name: str
     ]
 
     uid = f"terminplaner-slot-{appointment_id}-{start_dt.strftime('%Y%m%d%H%M')}@invario.eu"
-    created_at = datetime.datetime.utcnow().strftime('%Y%m%dT%H%M%SZ')
+    created_at = datetime.datetime.now(datetime.timezone.utc).strftime('%Y%m%dT%H%M%SZ')
     dt_start = start_dt.strftime('%Y%m%dT%H%M%S')
     dt_end = end_dt.strftime('%Y%m%dT%H%M%S')
 
@@ -198,7 +201,7 @@ def build_client_slot_ics(appointment_id: str, slot_start: str, client_name: str
     return '\r\n'.join(ics_lines)
 
 
-def new(date_start: str, date_end: str, time_span: list, slots, slot_length, user: str, mail: list=None, note:str="", calendar_enabled: bool=False, title: str="") -> dict:
+def new(date_start: str, date_end: str, time_span: list, slots, slot_length, user: str, mail: list=None, note:str="", calendar_enabled: bool=False, title: str="", custom_fields: list = (), clients_per_slot: int=1) -> dict:
     """
     Generates a link for the executive to send to his clients to book a time Slot
     """
@@ -207,6 +210,11 @@ def new(date_start: str, date_end: str, time_span: list, slots, slot_length, use
     except (ValueError, TypeError):
         slots_int = 0
         
+    try:
+        custom_fields.pop(-1)
+    except :
+        pass
+
     try:
         slot_length_int = int(slot_length)
     except (ValueError, TypeError):
@@ -215,7 +223,7 @@ def new(date_start: str, date_end: str, time_span: list, slots, slot_length, use
     normalized_time_span = _normalize_time_span(time_span)
     normalized_mail = _normalize_mail_list(mail or [])
     
-    id = termin.add(date_start, date_end, normalized_time_span, slots_int, slot_length_int, user, normalized_mail, note, calendar_enabled=calendar_enabled, title=title)
+    id = termin.add(date_start, date_end, normalized_time_span, slots_int, slot_length_int, user, normalized_mail, note, calendar_enabled=calendar_enabled, title=title, custom_fields=custom_fields, clients_p_slot=clients_per_slot)
     id_str = str(id)
     tenant_id = _current_tenant_id()
 
@@ -254,7 +262,7 @@ def new(date_start: str, date_end: str, time_span: list, slots, slot_length, use
     }
     
         
-def book_slot(id, date_start_time, name):
+def book_slot(id, date_start_time, name, custom: tuple = ()):
     try:
         item = termin.get_item(id)
         if not item:
@@ -264,18 +272,32 @@ def book_slot(id, date_start_time, name):
         if not isinstance(slots, list):
             slots = []
 
+        # 1. Check overall total booking capacity 
         capacity = int(item.get('slots', 0) or 0)
         if capacity and len(slots) >= capacity:
             return False
 
+        # 2. Prevent the exact same user from double-booking the exact same slot
         for existing in slots:
             if isinstance(existing, (list, tuple)) and len(existing) >= 2:
                 if existing[0] == date_start_time and existing[1] == name:
                     return False
 
-        slots.append((date_start_time, name))
+        # 3. Check concurrent capacity for this specific time slot
+        clients_per_slot = int(item.get('clients_per_slot', 1) or 1)
+        bookings_at_time = sum(
+            1 for existing in slots 
+            if isinstance(existing, (list, tuple)) and len(existing) > 0 and existing[0] == date_start_time
+        )
+        
+        if bookings_at_time >= clients_per_slot:
+            return False
+
+        # Append the new booking successfully
+        slots.append((date_start_time, name, custom))
         success = termin.update(id, slots)
         return bool(success)
+        
     except Exception as e:
         print(f"Error booking slot: {e}")
         return False
@@ -326,32 +348,46 @@ def get_available(id):
         date_end = termin_range.get('date_end')
         time_span = termin_range.get('time_span', [])
         
+        # Safe integer parsing without heavy try-except blocks
         try:
             total_slots = int(termin_range.get('slots', 0) or 0)
-        except Exception:
+        except (ValueError, TypeError):
             total_slots = 0
 
+        # Support both spellings gracefully
+        raw_length = termin_range.get('slot_length') or termin_range.get('slot_lenght') or 0
         try:
-            slot_length = int(termin_range.get('slot_length') or termin_range.get('slot_lenght') or 0)
-        except Exception:
-            slot_length = termin_range.get('slot_length') or termin_range.get('slot_lenght')
+            slot_length = int(raw_length)
+        except (ValueError, TypeError):
+            slot_length = raw_length
 
+        clients_per_slot = int(termin_range.get('clients_per_slot', 1) or 1)
         booked = termin_range.get('slots_booked', []) or []
 
+        # Normalize the bookings list safely
         normalized = []
+        bookings_by_time = {}  # Tracks how many people are in each specific time slot
+        
         for s in booked:
             if isinstance(s, (list, tuple)) and len(s) >= 2:
-                normalized.append({'start': s[0], 'name': s[1]})
+                slot_time = s[0]
+                item = {'start': slot_time, 'name': s[1]}
             elif isinstance(s, dict):
-                normalized.append(s)
+                slot_time = s.get('start')
+                item = s
             else:
-                normalized.append({'value': s})
+                slot_time = str(s)
+                item = {'value': s}
+                
+            normalized.append(item)
+            
+            # Count concurrent bookings per timestamp
+            if slot_time:
+                bookings_by_time[slot_time] = bookings_by_time.get(slot_time, 0) + 1
 
+        # Calculate remaining total capacity safely
         slots_used = len(normalized)
-        try:
-            slots_left = max(0, int(total_slots) - slots_used)
-        except Exception:
-            slots_left = max(0, slots_used - slots_used)
+        slots_left = max(0, total_slots - slots_used)
 
         return {
             'date_start': date_start,
@@ -360,8 +396,10 @@ def get_available(id):
             'slot_length': slot_length,
             'slot_lenght': slot_length,
             'slots_total': total_slots,
+            'clients_per_slot': clients_per_slot,
             'slots_booked': normalized,
             'slots_left': slots_left,
+            'bookings_by_time': bookings_by_time
         }
     except Exception as e:
         print(f"Error getting available slots: {e}")
@@ -370,7 +408,6 @@ def get_available(id):
 def get_available_user(id):
     return get_available(id)
 
-
 def get_user_upcoming_events(user: str, limit: int = 25) -> list[dict]:
     user_name = str(user or '').strip()
     if not user_name:
@@ -418,6 +455,7 @@ def get_user_upcoming_events(user: str, limit: int = 25) -> list[dict]:
                 'link': link,
                 'calendar_link': calendar_link if item.get('calendar_enabled') else None,
                 'title': str(item.get('title') or ''),
+                'custom_fields': list(item.get('custom_fields')),
             }
         )
 

Web/modules/terminplaner/blueprint.py

@@ -4,6 +4,9 @@ import Web.modules.terminplaner.backend_server as appointment_service
 import Web.modules.database.settings as cfg
 import Web.modules.database.termine as termin
 import Web.modules.database.user as us
+import csv
+import io
+from flask import make_response, flash, redirect, url_for, session
 
 # Create a blueprint instance
 appoint_bp = Blueprint('terminplaner', __name__)
@@ -34,10 +37,70 @@ def _current_tenant_id():
         pass
     return str(session.get('tenant_id', '') or '').strip()
 
+@appoint_bp.route('/client/<appointment_id>/export_csv')
+def export_csv(appointment_id):
+    """
+    Generiert einen CSV-Export aller Buchungen für den Ersteller.
+    """
+    # 1. Berechtigungsprüfung (analog zur Client-Route)
+    current_user = str(session.get('username', '') or '').strip()
+    appointment_item = termin.get_item(appointment_id) or {}
+    appointment_owner = str(appointment_item.get('user', '') or '').strip()
+    
+    can_view = False
+    if current_user:
+        try:
+            can_view = bool(us.check_admin(current_user) or current_user == appointment_owner)
+        except Exception:
+            can_view = bool(current_user == appointment_owner)
+            
+    if not can_view:
+        flash('Nicht autorisiert für diesen Export.', 'error')
+        return redirect(url_for('terminplaner.client', appointment_id=appointment_id))
+
+    custom_fields = appointment_item.get('custom_fields', [])
+    bookings = appointment_item.get('slots_booked', []) or []
+
+    # 2. CSV im Speicher erstellen
+    si = io.StringIO()
+    # Wir nutzen ein Semikolon als Trennzeichen – das öffnet Excel im deutschsprachigen Raum direkt fehlerfrei
+    cw = csv.writer(si, delimiter=';', quoting=csv.QUOTE_MINIMAL)
+    
+    # Tabellenkopf schreiben
+    headers = ['Zeitpunkt', 'Name'] + list(custom_fields)
+    cw.writerow(headers)
+    
+    # Datenzeilen schreiben
+    for booking in bookings:
+        if isinstance(booking, (list, tuple)):
+            row = [booking[0], booking[1]]
+            
+            # Antworten holen und sicherstellen, dass Lücken (falls vorhanden) mit Leerstrings gefüllt werden
+            answers = booking[2] if len(booking) > 2 else []
+            for i in range(len(custom_fields)):
+                if i < len(answers):
+                    row.append(answers[i])
+                else:
+                    row.append('')
+            cw.writerow(row)
+
+    # 3. Response vorbereiten und UTF-8-BOM für Excel mitsenden
+    response_content = si.getvalue()
+    output = make_response(response_content)
+    
+    output.data = b'\xef\xbb\xbf' + output.data
+    
+    # Dateiname generieren
+    title_slug = appointment_item.get('title', 'export').replace(' ', '_')
+    output.headers["Content-Disposition"] = f"attachment; filename=buchungen_{title_slug}.csv"
+    output.headers["Content-Type"] = "text/csv; charset=utf-8"
+    
+    return output
+
 @appoint_bp.route('/client/<appointment_id>', methods=['POST', 'GET'])
 def client(appointment_id):
     """
-    The Route for the terminplaner to work with the client
+    The Route for the terminplaner to work with the client and allow owners to manage it.
     """
     guard = _require_module_enabled()
     if guard:
@@ -50,6 +113,10 @@ def client(appointment_id):
     current_user = str(session.get('username', '') or '').strip()
     appointment_item = termin.get_item(appointment_id) or {}
     appointment_owner = str(appointment_item.get('user', '') or '').strip()
+    
+    custom_fields = appointment_item.get('custom_fields', [])
+
+    # Permissions check
     can_view_booking_names = False
     if current_user:
         try:
@@ -57,6 +124,7 @@ def client(appointment_id):
         except Exception:
             can_view_booking_names = bool(current_user == appointment_owner)
 
+    # Sanitize data for public/client view
     available_for_view = dict(available)
     if not can_view_booking_names:
         sanitized_bookings = []
@@ -70,31 +138,58 @@ def client(appointment_id):
         available_for_view['slots_booked'] = sanitized_bookings
 
     if request.method == 'POST':
-        start_daytime = request.form.get('start_day_time')
-        username = request.form.get('client_name')
-        if not start_daytime or not username:
-            flash('Bitte Name und gewünschte Uhrzeit angeben.', 'error')
-            return render_template(
-                'termin_client.html',
-                appointment_id=appointment_id,
-                available=available_for_view,
-                current_user=session.get('username', ''),
-                tenant_id=_current_tenant_id(),
-                can_view_booking_names=can_view_booking_names,
-            )
+        action = request.form.get('action', 'book')
 
-        if appointment_service.book_slot(appointment_id, start_daytime, username):
-            return redirect(
-                url_for(
-                    'terminplaner.client_success',
+        # Case 1: Admin/Owner cancels a booking
+        if action == 'delete' and can_view_booking_names:
+            slot_time = request.form.get('slot_time')
+            client_name = request.form.get('target_client_name')
+            
+            current_slots = appointment_item.get('slots_booked', []) or []
+            
+            # Keep everything EXCEPT the item targeted for deletion
+            updated_slots = [
+                slot for slot in current_slots 
+                if not (isinstance(slot, (list, tuple)) and slot[0] == slot_time and slot[1] == client_name)
+            ]
+            
+            if termin.update(appointment_id, updated_slots):
+                flash('Buchung wurde erfolgreich gelöscht.', 'success')
+            else:
+                flash('Fehler beim Löschen der Buchung.', 'error')
+                
+            return redirect(url_for('terminplaner.client', appointment_id=appointment_id, tenant=_current_tenant_id() or None))
+
+        # Case 2: Client books a slot
+        elif action == 'book':
+            start_daytime = request.form.get('start_day_time')
+            username = request.form.get('client_name')
+            custom_answers = tuple(request.form.getlist('custom_answers'))  # Cast to tuple for DB safety
+
+            if not start_daytime or not username:
+                flash('Bitte Name und gewünschte Uhrzeit angeben.', 'error')
+                return render_template(
+                    'termin_client.html',
                     appointment_id=appointment_id,
-                    tenant=_current_tenant_id() or None,
-                    start=start_daytime,
-                    name=username,
+                    available=available_for_view,
+                    current_user=session.get('username', ''),
+                    tenant_id=_current_tenant_id(),
+                    can_view_booking_names=can_view_booking_names,
+                    custom_fields=custom_fields 
                 )
-            )
 
-        flash('Der Termin konnte nicht gespeichert werden.', 'error')
+            if appointment_service.book_slot(appointment_id, start_daytime, username, custom=custom_answers):
+                return redirect(
+                    url_for(
+                        'terminplaner.client_success',
+                        appointment_id=appointment_id,
+                        tenant=_current_tenant_id() or None,
+                        start=start_daytime,
+                        name=username,
+                    )
+                )
+
+            flash('Der Termin konnte nicht gespeichert werden. Eventuell ist der Slot bereits voll.', 'error')
 
     return render_template(
         'termin_client.html',
@@ -103,6 +198,8 @@ def client(appointment_id):
         current_user=session.get('username', ''),
         tenant_id=_current_tenant_id(),
         can_view_booking_names=can_view_booking_names,
+        custom_fields=custom_fields,
+        appointment_item=appointment_item
     )
 
 
@@ -154,7 +251,7 @@ def delete_appointment(appointment_id):
 @appoint_bp.route('/configure', methods=['GET', 'POST'])
 def configure():
     """
-    Route for authenticated persons to configure a new appointment for them
+    Route for authenticated persons to configure a new appointment schedule
     """
     guard = _require_module_enabled()
     if guard:
@@ -169,13 +266,18 @@ def configure():
         end = request.form.get('end_date')
         time = request.form.get('time_frame')
         slots_amount = request.form.get('slots_amounts')
-        slot_length = request.form.get('slot_length') # Korrigiert: slot_length
+        slot_length = request.form.get('slot_length') 
         mail = request.form.get('mail', '')
         note = request.form.get('note', '')
         add_to_calendar = request.form.get('add_to_calendar') == 'on'
-        title = request.form.get('title', '').strip() # Korrigiert: title statt titel
+        title = request.form.get('title', '').strip()
+        custom = request.form.getlist('custom_fields')
+        
+        try:
+            clients_p_slot = int(request.form.get('clients_per_slot', 1))
+        except (ValueError, TypeError):
+            clients_p_slot = 1
 
-        # Abfrage ebenfalls auf title und slot_length angepasst
         if not start or not end or not time or not slots_amount or not slot_length or not title:
             flash('Bitte alle Pflichtfelder ausfüllen.', 'error')
             return render_template(
@@ -185,28 +287,46 @@ def configure():
                 email_service_enabled=cfg.EMAIL_ENABLED,
             )
 
-        # Variablen im Funktionsaufruf aktualisiert
-        result = appointment_service.new(start, end, time, slots_amount, slot_length, session["username"], mail, note, calendar_enabled=add_to_calendar, title=title)
+        # Call the database service function (standardized to match your underlying code)
+        inserted_id = appointment_service.new(
+            date_start=start, 
+            date_end=end, 
+            time_span=time, 
+            slots=slots_amount, 
+            slot_length=slot_length, 
+            user=session["username"], 
+            mail=mail, 
+            note=note, 
+            calendar_enabled=add_to_calendar, 
+            title=title, 
+            custom_fields=custom,
+            clients_per_slot=clients_p_slot
+        )
+
+        if not inserted_id:
+            flash('Fehler beim Erstellen des Terminplans.', 'error')
+            return redirect(url_for('terminplaner.configure'))
+
         flash('Der Terminplan wurde angelegt.', 'success')
         return render_template(
             'termin_configure.html',
             school_periods=cfg.SCHOOL_PERIODS,
-            generated_link=result['link'],
-            calendar_link=result.get('calendar_link'),
+            generated_link=inserted_id['link'],
+            calendar_link=None, 
             add_to_calendar=add_to_calendar,
             email_service_enabled=cfg.EMAIL_ENABLED,
             title=title,
         )
-    elif request.method == "GET":
-        return render_template(
-            'termin_configure.html',
-            school_periods=cfg.SCHOOL_PERIODS,
-            generated_link=None,
-            calendar_link=None,
-            add_to_calendar=False,
-            email_service_enabled=cfg.EMAIL_ENABLED,
-            title=None,
-        )
+
+    return render_template(
+        'termin_configure.html',
+        school_periods=cfg.SCHOOL_PERIODS,
+        generated_link=None,
+        calendar_link=None,
+        add_to_calendar=False,
+        email_service_enabled=cfg.EMAIL_ENABLED,
+        title=None,
+    )
 
 
 @appoint_bp.route('/calendar/<appointment_id>.ics', methods=['GET'])

Web/templates/termin_client.html

@@ -39,13 +39,19 @@
     <div class="row justify-content-center">
         <div class="col-12 col-xxl-11">
             <div class="row g-4">
+                
                 <div class="col-12 col-lg-4">
                     <div class="card border-0 shadow-lg rounded-4 h-100">
                         <div class="card-body p-4 p-md-5">
                             <p class="text-uppercase text-muted fw-semibold mb-2">Terminplaner</p>
-                            <h1 class="h3 fw-bold mb-3">Termin buchen - {{ available.title }}</h1>
-                            <p class="text-muted mb-4">Wählen Sie im Kalender einen freien Slot aus. Den gewählten Termin können Sie danach direkt wie in einem Kalender-Block verschieben.</p>
-
+                            {% if can_view_booking_names %}
+                                <h1 class="h3 fw-bold mb-3">Termin Übersicht - {{ available.title }}</h1>
+                                <p class="text-muted mb-4">Hier können Sie alle Buchungen, die bereits eingegangen sind, einsehen und verwalten.</p>
+                            {% else %}
+                                <h1 class="h3 fw-bold mb-3">Termin buchen - {{ available.title }}</h1>
+                                <p class="text-muted mb-4">Wählen Sie im Kalender einen freien Slot aus. Den gewählten Termin können Sie danach direkt wie in einem Kalender-Block verschieben.</p>
+                            {% endif %}
+                            
                             <div class="p-3 rounded-3 bg-light mb-3">
                                 <div class="fw-semibold">Zeitraum</div>
                                 <div>{{ available.date_start }} bis {{ available.date_end }}</div>
@@ -58,23 +64,24 @@
                                 <div class="fw-semibold">Slot-Länge</div>
                                 <div>{{ available.slot_lenght }} Minuten</div>
                             </div>
-
+                            
+                            {% if not can_view_booking_names %}
                             <div class="p-3 rounded-3 bg-light mb-3">
                                 <div class="fw-semibold mb-2">Gewählter Termin</div>
                                 <div id="selected-slot-badge" class="text-muted small">Noch kein Slot ausgewählt.</div>
                             </div>
+                            {% endif %}
 
                             {% if available.slots_booked %}
                             <div class="p-3 rounded-3 bg-light">
                                 <div class="fw-semibold mb-2">Bereits gebucht</div>
-                                <ul class="mb-0 small">
+                                <ul class="mb-0 small text-muted">
                                     {% for booking in available.slots_booked %}
                                     <li>
-                                        {{ booking.start }}
-                                        {% if can_view_booking_names and booking.name %}
-                                        - {{ booking.name }}
+                                        {% if booking is mapping %}
+                                            {{ booking.get('start', '') }} - Belegt
                                         {% else %}
-                                        - Belegt
+                                            {{ booking[0] }} - {% if can_view_booking_names %}<span class="fw-semibold text-dark">{{ booking[1] }}</span>{% else %}Belegt{% endif %}
                                         {% endif %}
                                     </li>
                                     {% endfor %}
@@ -84,39 +91,161 @@
                         </div>
                     </div>
                 </div>
+
                 <div class="col-12 col-lg-8">
                     <div class="card border-0 shadow-lg rounded-4 h-100">
                         <div class="card-body p-4 p-md-5 bg-white">
-                            <h2 class="h4 fw-bold mb-3">Termin im Kalender auswählen</h2>
-
-                            <div class="day-slider-wrap mb-3">
-                                <div class="d-flex justify-content-between align-items-center gap-2 mb-2">
-                                    <span class="small text-muted">Tag wählen</span>
-                                    <strong id="day-slider-label" class="small"></strong>
+                            
+                            {% if can_view_booking_names %}
+                                <!-- ADMIN / AUTOREN ANSICHT -->
+                                <div class="d-flex flex-column flex-md-row justify-content-between align-items-md-center gap-3 mb-4">
+                                    <div>
+                                        <h2 class="h4 fw-bold mb-0">Eingegangene Buchungen</h2>
+                                        <div class="text-muted small">Verwalten Sie die Termine Ihrer Klienten</div>
+                                    </div>
+                                    <div class="d-flex gap-2 align-self-start align-self-md-center">
+                                        <!-- Neuer CSV Export Button -->
+                                        <a href="{{ url_for('terminplaner.export_csv', appointment_id=appointment_id) }}" class="btn btn-outline-success rounded-3 d-inline-flex align-items-center gap-2">
+                                            <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-download" viewBox="0 0 16 16">
+                                                <path d="M.5 9.9a.5.5 0 0 1 .5.5v2.5a1 1 0 0 0 1 1h12a1 1 0 0 0 1-1v2.5a.5.5 0 0 1 1 0v2.5a2 2 0 0 1-2 2H2a2 2 0 0 1-2-2v2.5a.5.5 0 0 1 .5-.5"/>
+                                                <path d="M7.646 11.854a.5.5 0 0 0 .708 0l3-3a.5.5 0 0 0-.708-.708L8.5 10.293V1.5a.5.5 0 0 0-1 0v8.793L5.354 8.146a.5.5 0 1 0-.708.708z"/>
+                                            </svg>
+                                            Excel / CSV Export
+                                        </a>
+                                        <span class="badge bg-primary rounded-pill fs-6 px-3 d-flex align-items-center">
+                                            {{ available.slots_total - available.slots_left }} von {{ available.slots_total }} belegt
+                                        </span>
+                                    </div>
                                 </div>
-                                <input id="day-slider" type="range" class="form-range m-0" min="0" max="0" value="0">
-                            </div>
-
-                            <div id="client-slot-calendar" class="mb-4"></div>
-
-                            <form id="client-booking-form" method="post" action="{{ url_for('terminplaner.client', appointment_id=appointment_id, tenant=tenant_id) }}" class="vstack gap-3">
-                                <div>
-                                    <label for="start_day_time" class="form-label fw-semibold">Gewünschter Zeitpunkt</label>
-                                    <input type="text" id="start_day_time" name="start_day_time" class="form-control form-control-lg" placeholder="Bitte im Kalender auswählen" readonly required>
-                                    <div class="form-text">Klicken Sie auf einen freien Slot oder verschieben Sie den gewählten Block.</div>
+                                <div class="bg-light p-3 rounded-3 mb-4">
+                                    <div class="row g-2 align-items-center">
+                                        <div class="col-12 col-md-8">
+                                            <label for="table-search" class="form-label small fw-semibold text-muted mb-1">Live-Filter (Name, Uhrzeit, Zusatzfelder...)</label>
+                                            <input type="text" id="table-search" class="form-control form-control-lg bg-white border" placeholder="Suchbegriff eingeben...">
+                                        </div>
+                                        <div class="col-12 col-md-4 d-flex align-items-end h-100 mt-md-4">
+                                            <button type="button" id="clear-filter-btn" class="btn btn-outline-secondary w-100 btn-lg">Filter zurücksetzen</button>
+                                        </div>
+                                    </div>
                                 </div>
-                                <div>
-                                    <label for="client_name" class="form-label fw-semibold">Ihr Name</label>
-                                    <input type="text" id="client_name" name="client_name" class="form-control form-control-lg" placeholder="Vor- und Nachname" required>
+
+                                {% if available.slots_booked %}
+                                <div class="table-responsive">
+                                    <table class="table table-hover align-middle border-top" id="admin-booking-table">
+                                        <thead class="table-light">
+                                            <tr>
+                                                <th scope="col" class="py-3">Zeitpunkt</th>
+                                                <th scope="col" class="py-3">Name</th>
+                                                <!-- Spaltenüberschriften für Custom Fields -->
+                                                {% for field_label in custom_fields %}
+                                                <th scope="col" class="py-3">{{ field_label }}</th>
+                                                {% endfor %}
+                                                <th scope="col" class="py-3 text-end">Aktion</th>
+                                            </tr>
+                                        </thead>
+                                        <tbody id="booking-table-body">
+                                            {# Wir loopen jetzt über die rohen DB-Daten statt über die beschnittene Service-Funktion #}
+                                            {% for booking in appointment_item.get('slots_booked', []) %}
+                                            <tr>
+                                                <!-- 1. ZEITPUNKT -->
+                                                <td class="fw-semibold text-primary py-3 text-nowrap">
+                                                    {{ booking[0] }}
+                                                </td>
+                                            
+                                                <!-- 2. CLIENT NAME -->
+                                                <td>
+                                                    <span class="fw-bold text-dark">{{ booking[1] }}</span>
+                                                </td>
+
+                                                <!-- 3. CUSTOM FIELDS (Präziser Index-Abgleich gegen Spaltenkopf) -->
+                                                {% for field in custom_fields %}
+                                                    <td>
+                                                        {# Prüft ob für dieses Feld eine Antwort am exakt gleichen Index existiert #}
+                                                        {% if booking|length > 2 and booking[2] and booking[2]|length > loop.index0 %}
+                                                            {% set answer = booking[2][loop.index0] %}
+                                                            {{ answer if answer else '<span class="text-muted small">-</span>'|safe }}
+                                                        {% else %}
+                                                            <span class="text-muted small">-</span>
+                                                        {% endif %}
+                                                    </td>
+                                                {% endfor %}
+                                                
+                                                <!-- 4. AKTION (LÖSCHEN) -->
+                                                <td class="text-end">
+                                                    <form method="post" action="{{ url_for('terminplaner.client', appointment_id=appointment_id, tenant=tenant_id) }}" onsubmit="return confirm('Möchten Sie diesen Termin wirklich löschen?');" class="d-inline">
+                                                        <input type="hidden" name="action" value="delete">
+                                                        <input type="hidden" name="slot_time" value="{{ booking[0] }}">
+                                                        <input type="hidden" name="target_client_name" value="{{ booking[1] }}">
+
+                                                        <button type="submit" class="btn btn-sm btn-outline-danger px-3 rounded-3">
+                                                            Löschen
+                                                        </button>
+                                                    </form>
+                                                </td>
+                                            </tr>
+                                            {% endfor %}
+                                        </tbody>
+                                    </table>
                                 </div>
-                                <div class="d-flex flex-column flex-sm-row gap-2 pt-2">
-                                    <button type="submit" class="btn btn-primary btn-lg">Termin buchen</button>
+                                
+                                <div id="no-results-msg" class="text-center py-4 text-muted d-none">
+                                    Keine Buchungen entsprechen Ihrem Filter.
+                                </div>
+                                {% else %}
+                                <div class="text-center py-5 text-muted">
+                                    <p class="mb-0">Bisher sind noch keine Buchungen für diesen Terminplaner eingegangen.</p>
+                                </div>
+                                {% endif %}
+                                
+                                <div class="pt-4 border-top mt-4">
                                     <a class="btn btn-outline-secondary btn-lg" href="{{ url_for('terminplaner.main', tenant=tenant_id) }}">Zur Übersicht</a>
                                 </div>
-                            </form>
+
+                            {% else %}
+                                <h2 class="h4 fw-bold mb-3">Termin im Kalender auswählen</h2>
+
+                                <div class="day-slider-wrap mb-3">
+                                    <div class="d-flex justify-content-between align-items-center gap-2 mb-2">
+                                        <span class="small text-muted">Tag wählen</span>
+                                        <strong id="day-slider-label" class="small"></strong>
+                                    </div>
+                                    <input id="day-slider" type="range" class="form-range m-0" min="0" max="0" value="0">
+                                </div>
+
+                                <div id="client-slot-calendar" class="mb-4"></div>
+
+                                <form id="client-booking-form" method="post" action="{{ url_for('terminplaner.client', appointment_id=appointment_id, tenant=tenant_id) }}" class="vstack gap-3">
+                                    <div>
+                                        <label for="start_day_time" class="form-label fw-semibold">Gewünschter Zeitpunkt</label>
+                                        <input type="text" id="start_day_time" name="start_day_time" class="form-control form-control-lg" placeholder="Bitte im Kalender auswählen" readonly required>
+                                        <div class="form-text">Klicken Sie auf einen freien Slot oder verschieben Sie den gewählten Block.</div>
+                                    </div>
+                                    <div>
+                                        <label for="client_name" class="form-label fw-semibold">Ihr Name</label>
+                                        <input type="text" id="client_name" name="client_name" class="form-control form-control-lg" placeholder="Vor- und Nachname" required>
+                                    </div>
+                                
+                                    {% if custom_fields %}
+                                        {% for field_label in custom_fields %}
+                                        <div>
+                                            <label class="form-label fw-semibold">{{ field_label }}</label>
+                                            <input type="text" name="custom_answers" class="form-control form-control-lg" placeholder="{{ field_label }} eingeben" required>
+                                        </div>
+                                        {% endfor %}
+                                    {% endif %}
+                                    
+                                    <div class="d-flex flex-column flex-sm-row gap-2 pt-2">
+                                        <input type="hidden" name="action" value="book">
+                                        <button type="submit" class="btn btn-primary btn-lg">Termin buchen</button>
+                                        <a class="btn btn-outline-secondary btn-lg" href="{{ url_for('terminplaner.main', tenant=tenant_id) }}">Zur Übersicht</a>
+                                    </div>
+                                </form>
+                            {% endif %}
+
                         </div>
                     </div>
                 </div>
+                
             </div>
         </div>
     </div>
@@ -142,11 +271,58 @@
     </div>
 </div>
 
+<script>
+document.addEventListener('DOMContentLoaded', function () {
+    const searchInput = document.getElementById('table-search');
+    const clearBtn = document.getElementById('clear-filter-btn');
+    const tableBody = document.getElementById('booking-table-body');
+    const noResultsMsg = document.getElementById('no-results-msg');
+
+    if (searchInput && tableBody) {
+        const rows = tableBody.querySelectorAll('tr');
+
+        searchInput.addEventListener('input', function () {
+            const query = this.value.toLowerCase().trim();
+            let visibleRowsCount = 0;
+
+            rows.forEach(row => {
+                // Liest den Textinhalt aller Spalten der Zeile aus
+                const rowText = row.textContent.toLowerCase();
+                
+                if (rowText.includes(query)) {
+                    row.classList.remove('d-none');
+                    visibleRowsCount++;
+                } else {
+                    row.classList.add('d-none');
+                }
+            });
+
+            // Falls kein Filterergebnis gefunden wurde, Nachricht einblenden
+            if (visibleRowsCount === 0 && query !== '') {
+                noResultsMsg.classList.remove('d-none');
+            } else {
+                noResultsMsg.classList.add('d-none');
+            }
+        });
+
+        // Filter zurücksetzen Button
+        if (clearBtn) {
+            clearBtn.addEventListener('click', function () {
+                searchInput.value = '';
+                rows.forEach(row => row.classList.remove('d-none'));
+                noResultsMsg.classList.add('d-none');
+                searchInput.focus();
+            });
+        }
+    }
+});
+</script>
 <script src="https://cdn.jsdelivr.net/npm/fullcalendar@6.1.15/index.global.min.js"></script>
 <script>
     (function () {
         const available = {{ available|tojson }};
         const appointmentId = {{ appointment_id|tojson }};
+        const canViewBookingNames = {{ can_view_booking_names|tojson }}; // Injected from Flask
         const slider = document.getElementById('day-slider');
         const sliderLabel = document.getElementById('day-slider-label');
         const sliderWrap = slider ? slider.closest('.day-slider-wrap') : null;
@@ -160,10 +336,10 @@
         const confirmBookingWithIcsBtn = document.getElementById('confirm-booking-with-ics');
         const modal = modalEl ? new bootstrap.Modal(modalEl) : null;
 
-        const slotLength = Number.parseInt(available.slot_lenght, 10) || 45;
-        const bookedStarts = new Set((available.slots_booked || []).map(function (entry) {
-            return String(entry.start || '').trim();
-        }).filter(Boolean));
+        // Fallback for both spellings of slot length
+        const slotLength = Number.parseInt(available.slot_length || available.slot_lenght, 10) || 45;
+        const clientsPerSlot = Number.parseInt(available.clients_per_slot, 10) || 1;
+        const bookingsByTime = available.bookings_by_time || {};
 
         function formatDateForInput(dateObj) {
             const y = dateObj.getFullYear();
@@ -227,6 +403,8 @@
             return null;
         }
 
+        const fullyBookedSlots = [];
+
         function buildCandidateSlots() {
             const slots = [];
             const allowedDates = dateRangeInclusive(String(available.date_start || ''), String(available.date_end || ''));
@@ -234,9 +412,7 @@
 
             spans.forEach(function (entry) {
                 const parsed = parseTimeSpanEntry(entry);
-                if (!parsed) {
-                    return;
-                }
+                if (!parsed) return;
 
                 const targetDates = parsed.date ? [parsed.date] : allowedDates;
                 targetDates.forEach(function (date) {
@@ -249,10 +425,19 @@
                     let cursor = new Date(from);
                     while (addMinutes(cursor, slotLength) <= to) {
                         const slotStart = formatDateForInput(cursor);
-                        if (!bookedStarts.has(slotStart)) {
+                        const currentBookingsCount = bookingsByTime[slotStart] || 0;
+                        
+                        // Check if the current individual timestamp still has capacity left
+                        if (currentBookingsCount < clientsPerSlot) {
                             slots.push({
                                 start: slotStart,
                                 end: formatDateForInput(addMinutes(cursor, slotLength)),
+                                bookingsCount: currentBookingsCount
+                            });
+                        } else {
+                            fullyBookedSlots.push({
+                                start: slotStart,
+                                end: formatDateForInput(addMinutes(cursor, slotLength))
                             });
                         }
                         cursor = addMinutes(cursor, slotLength);
@@ -267,27 +452,8 @@
         const slotStartSet = new Set(candidateSlots.map(function (slot) { return slot.start; }));
         const allDays = dateRangeInclusive(String(available.date_start || ''), String(available.date_end || ''));
 
-        // Show the requested UI time window from 08:15 to 20:00 and highlight available slots
-        let slotMinTime = '08:15:00';
+        let slotMinTime = '08:00:00';
         let slotMaxTime = '20:00:00';
-        if (candidateSlots.length > 0) {
-            const starts = candidateSlots.map(function (slot) {
-                return new Date(slot.start.replace(' ', 'T') + ':00');
-            }).filter(function (d) { return !Number.isNaN(d.getTime()); });
-            const ends = candidateSlots.map(function (slot) {
-                return new Date(slot.end.replace(' ', 'T') + ':00');
-            }).filter(function (d) { return !Number.isNaN(d.getTime()); });
-
-            // Keep the computed min/max for gap calculations below
-            var computedMinStart = null;
-            var computedMaxEnd = null;
-            if (starts.length > 0 && ends.length > 0) {
-                computedMinStart = starts[0];
-                computedMaxEnd = ends[0];
-                starts.forEach(function (d) { if (d < computedMinStart) computedMinStart = d; });
-                ends.forEach(function (d) { if (d > computedMaxEnd) computedMaxEnd = d; });
-            }
-        }
 
         const visibleStart = allDays[0] || String(available.date_start || '');
         const visibleEndExclusive = allDays.length > 0
@@ -322,14 +488,8 @@
             slotMinTime: slotMinTime,
             slotMaxTime: slotMaxTime,
             nowIndicator: true,
-            validRange: {
-                start: visibleStart,
-                end: visibleEndExclusive,
-            },
-            visibleRange: {
-                start: visibleStart,
-                end: visibleEndExclusive,
-            },
+            validRange: { start: visibleStart, end: visibleEndExclusive },
+            visibleRange: { start: visibleStart, end: visibleEndExclusive },
             headerToolbar: {
                 left: '',
                 center: 'title',
@@ -337,28 +497,22 @@
             },
             events: [],
             eventDrop: function (info) {
-                if (info.event.id !== 'selected-slot') {
-                    return;
-                }
+                if (info.event.id !== 'selected-slot') return;
                 const droppedStart = formatDateForInput(info.event.start);
                 if (!slotStartSet.has(droppedStart)) {
                     info.revert();
-                    window.alert('Dieser Zeitpunkt ist nicht als freier Slot verfügbar.');
+                    window.alert('Dieser Zeitpunkt ist ausgebucht oder nicht verfügbar.');
                     return;
                 }
                 applySelectedSlot(droppedStart);
             },
             eventClick: function (info) {
                 const slotType = info.event.extendedProps ? info.event.extendedProps.slotType : '';
-                if (slotType !== 'free') {
-                    return;
-                }
+                if (slotType !== 'free') return;
                 applySelectedSlot(info.event.extendedProps.slotStart || '');
             }
         });
 
-        // No background greying: show full calendar skeleton and only mark possible slots
-
         function updateSliderLabel() {
             const dateList = dateRangeInclusive(String(available.date_start || ''), String(available.date_end || ''));
             const idx = Number.parseInt(slider.value, 10) || 0;
@@ -377,9 +531,7 @@
                 selectedEvent = null;
             }
 
-            if (!selectedSlot) {
-                return;
-            }
+            if (!selectedSlot) return;
 
             const start = new Date(selectedSlot.replace(' ', 'T') + ':00');
             const end = addMinutes(start, slotLength);
@@ -398,13 +550,9 @@
         function getIcsDownloadUrl() {
             const base = {{ url_for('terminplaner.client_slot_calendar_export', appointment_id=appointment_id, tenant=tenant_id)|tojson }};
             const url = new URL(base, window.location.origin);
-            if (selectedSlot) {
-                url.searchParams.set('start', selectedSlot);
-            }
+            if (selectedSlot) url.searchParams.set('start', selectedSlot);
             const name = String(clientNameInput.value || '').trim();
-            if (name) {
-                url.searchParams.set('name', name);
-            }
+            if (name) url.searchParams.set('name', name);
             return url.toString();
         }
 
@@ -415,14 +563,19 @@
             }
         }
 
-        // No background gaps: keep full skeleton/grid visible
-
-        // Add candidate free slots (blue)
+        // Render Active/Available Slots with Live Seat Counts
         candidateSlots.forEach(function (slot) {
             const start = new Date(slot.start.replace(' ', 'T') + ':00');
             const end = new Date(slot.end.replace(' ', 'T') + ':00');
+            
+            let displayTitle = 'Freier Slot';
+            if (clientsPerSlot > 1) {
+                const remainingSeats = clientsPerSlot - slot.bookingsCount;
+                displayTitle += ' (' + remainingSeats + '/' + clientsPerSlot + ' frei)';
+            }
+
             calendar.addEvent({
-                title: 'Freier Slot',
+                title: displayTitle,
                 start: start,
                 end: end,
                 color: '#0d6efd',
@@ -435,46 +588,54 @@
             });
         });
 
-        (available.slots_booked || []).forEach(function (booking) {
-            const startStr = String(booking.start || '').trim();
-            if (!startStr) {
-                return;
-            }
-            const start = new Date(startStr.replace(' ', 'T') + ':00');
-            const end = addMinutes(start, slotLength);
+        // Client View Optimization: Render solid red events ONLY if a slot is 100% full
+        fullyBookedSlots.forEach(function (slot) {
+            const start = new Date(slot.start.replace(' ', 'T') + ':00');
+            const end = new Date(slot.end.replace(' ', 'T') + ':00');
             calendar.addEvent({
-                title: 'Gebucht' + (booking.name ? ' - ' + booking.name : ''),
+                title: 'Ausgebucht',
                 start: start,
                 end: end,
                 color: '#dc3545',
                 editable: false,
-                display: 'block',
+                display: 'block'
             });
         });
 
+        // Admin Management View: Render detailed name blocks exclusively for management interaction
+        if (canViewBookingNames) {
+            (available.slots_booked || []).forEach(function (booking) {
+                const startStr = String(booking.start || '').trim();
+                if (!startStr) return;
+                const start = new Date(startStr.replace(' ', 'T') + ':00');
+                const end = addMinutes(start, slotLength);
+                calendar.addEvent({
+                    title: 'Belegt: ' + (booking.name || 'Anonym'),
+                    start: start,
+                    end: end,
+                    color: '#9e9e9e',
+                    editable: false,
+                    display: 'block',
+                });
+            });
+        }
+
+        // Event Listeners and Setup
         form.addEventListener('submit', function (ev) {
             if (!selectedSlotInput.value) {
                 ev.preventDefault();
                 window.alert('Bitte zuerst im Kalender einen freien Slot auswählen.');
                 return;
             }
-
-            if (allowImmediateSubmit) {
-                return;
-            }
-
+            if (allowImmediateSubmit) return;
             ev.preventDefault();
-            if (modal) {
-                modal.show();
-            }
+            if (modal) modal.show();
         });
 
         if (confirmBookingOnlyBtn) {
             confirmBookingOnlyBtn.addEventListener('click', function () {
                 allowImmediateSubmit = true;
-                if (modal) {
-                    modal.hide();
-                }
+                if (modal) modal.hide();
                 form.submit();
             });
         }
@@ -482,13 +643,9 @@
         if (confirmBookingWithIcsBtn) {
             confirmBookingWithIcsBtn.addEventListener('click', function () {
                 const icsUrl = confirmBookingWithIcsBtn.getAttribute('data-ics-url') || getIcsDownloadUrl();
-                if (icsUrl) {
-                    window.open(icsUrl, '_blank');
-                }
+                if (icsUrl) window.open(icsUrl, '_blank');
                 allowImmediateSubmit = true;
-                if (modal) {
-                    modal.hide();
-                }
+                if (modal) modal.hide();
                 form.submit();
             });
         }
@@ -509,10 +666,8 @@
         slider.addEventListener('input', function () {
             const idx = Number.parseInt(slider.value, 10) || 0;
             updateSliderLabel();
-            if (allDays[idx]) {
-                if (calendar.view.type === 'timeGridDay') {
-                    calendar.gotoDate(allDays[idx]);
-                }
+            if (allDays[idx] && calendar.view.type === 'timeGridDay') {
+                calendar.gotoDate(allDays[idx]);
             }
         });
 

Web/templates/termin_configure.html

@@ -70,6 +70,10 @@
                                 <label for="slot_length" class="form-label fw-semibold">Slot-Länge in Minuten</label>
                                 <input type="number" id="slot_length" name="slot_length" class="form-control form-control-lg" min="1" value="45">
                             </div>
+                            <div>
+                                <label class="form-label fw-semibold text-primary">Nutzer pro Slot</label>
+                                <input type="number" id="clients_per_slot" name="clients_per_slot" value="1">
+                            </div>
                             <div class="col-12 col-md-6">
                                 <label class="form-label fw-semibold text-primary">Automatisch berechnete Slots</label>
                                 <div id="slots_amounts_display" class="form-control form-control-lg bg-primary-subtle text-primary fw-bold d-flex align-items-center">0</div>
@@ -77,6 +81,16 @@
                                 <div class="form-text">Wird aus der gebuchten Zeit (abzüglich Pausen) und der Slot-Länge berechnet.</div>
                             </div>
                         </div>
+                        <div id="custom-fields-container" class="mt-4">
+                            <h3 class="mb-3">Benutzerdefinierte Felder</h3>
+
+                            <div class="mb-3 custom-field-row">
+                                <input type="text" 
+                                       name="custom_fields" 
+                                       class="form-control form-control-lg custom-dynamic-input" 
+                                       placeholder="Zusatzfeld hinzufügen (z.B. Firma, Kundennummer...)">
+                            </div>
+                        </div>
 
                         {% if mail_service_enabled %}
                             <div>
@@ -139,6 +153,7 @@
     const defaultPauseEndInput = document.getElementById('default_pause_end');
     
     const slotLengthInput = document.getElementById('slot_length');
+    const clientsperslot = document.getElementById('clients_per_slot')
     const slotsAmountsInput = document.getElementById('slots_amounts');
     const slotsAmountsDisplay = document.getElementById('slots_amounts_display'); // Neu: Anzeige-Element
 
@@ -188,16 +203,31 @@
         if (slotsAmountsDisplay) slotsAmountsDisplay.innerText = totalSlots + " Slots gesamt";
     }
 
+    // Helper utility in case your timeToMinutes handler doesn't catch empty strings safely
+    function safeTimeToMinutes(timeString) {
+        if (!timeString || typeof timeString !== 'string' || !timeString.includes(':')) {
+            return 0; // Return 0 instead of NaN for empty or missing values
+        }
+        const parts = timeString.split(':');
+        const hours = parseInt(parts[0], 10);
+        const minutes = parseInt(parts[1], 10);
+        if (isNaN(hours) || isNaN(minutes)) return 0;
+        return (hours * 60) + minutes;
+    }
+
     // Berechnet die Slots basierend auf den konfigurierten Zeiten & Pausen
     function calculateSlots() {
-        if (!slotLengthInput || !slotsAmountsInput) return;
-        
+        if (!slotLengthInput || !slotsAmountsInput || !clientsperslot) return;
+
         const slotLength = parseInt(slotLengthInput.value, 10);
         if (isNaN(slotLength) || slotLength <= 0) {
             updateSlotsDisplay(0);
             return;
         }
 
+        // FIX 1: Make sure we parse the input VALUE, defaulting to 1 if empty or invalid
+        const multiplier = parseInt(clientsperslot.value, 10) || 1;
+
         let totalSlots = 0;
         const rows = Array.from(daysContainer.querySelectorAll('[data-day-row]'));
 
@@ -209,19 +239,20 @@
 
             if (!startTime || !endTime) return;
 
-            const startMins = timeToMinutes(startTime);
-            const endMins = timeToMinutes(endTime);
-            const pauseStartMins = timeToMinutes(pauseStart);
-            const pauseEndMins = timeToMinutes(pauseEnd);
+            // Using safety parsing to prevent missing values from generating NaN
+            const startMins = safeTimeToMinutes(startTime);
+            const endMins = safeTimeToMinutes(endTime);
+            const pauseStartMins = safeTimeToMinutes(pauseStart);
+            const pauseEndMins = safeTimeToMinutes(pauseEnd);
 
-            if (endMins <= startMins) return; // Ungültige Zeit
+            if (isNaN(startMins) || isNaN(endMins) || endMins <= startMins) return;
 
             // Wenn eine gültige Pause innerhalb der Start/Endzeit existiert
             if (pauseStartMins > 0 && pauseEndMins > 0 && pauseStartMins < pauseEndMins && pauseStartMins > startMins && pauseStartMins < endMins) {
                 // Segment 1 (Vor der Pause)
                 const segment1 = pauseStartMins - startMins;
                 totalSlots += Math.floor(segment1 / slotLength);
-                
+
                 // Segment 2 (Nach der Pause)
                 const effectivePauseEnd = Math.min(pauseEndMins, endMins);
                 const segment2 = endMins - effectivePauseEnd;
@@ -234,7 +265,11 @@
             }
         });
 
-        updateSlotsDisplay(totalSlots);
+        // FIX 2: Multiply by our safely parsed input value scalar
+        const totalSlotscomplete = totalSlots * multiplier;
+
+        // Safety check: if anything went wrong anyway, fallback to 0 instead of displaying NaN
+        updateSlotsDisplay(isNaN(totalSlotscomplete) ? 0 : totalSlotscomplete);
     }
 
     // Synchronisiert das Textfeld und fügt den Break-Cut hinzu
@@ -351,6 +386,39 @@
         syncTextarea();
     }
 
+    document.addEventListener('DOMContentLoaded', function () {
+        const container = document.getElementById('custom-fields-container');
+
+        // Monitor inputs inside the container using event delegation
+        container.addEventListener('input', function (event) {
+            // Only trigger if the user is typing inside our dynamic inputs
+            if (event.target.classList.contains('custom-dynamic-input')) {
+                const allInputs = container.querySelectorAll('.custom-dynamic-input');
+                const lastInput = allInputs[allInputs.length - 1];
+
+                // If the user typed something into the absolute last input field, spawn a new one
+                if (lastInput.value.trim() !== '') {
+                    createNewFieldRow(container);
+                }
+            }
+        });
+
+        // Helper function to generate and append a clean new input row
+        function createNewFieldRow(targetContainer) {
+            const rowDiv = document.createElement('div');
+            rowDiv.className = 'mb-3 custom-field-row';
+
+            rowDiv.innerHTML = `
+                <input type="text" 
+                       name="custom_fields" 
+                       class="form-control form-control-lg custom-dynamic-input" 
+                       placeholder="Nächstes Zusatzfeld...">
+            `;
+
+            targetContainer.appendChild(rowDiv);
+        }
+    });
+
     // Event Listeners Registration
     buildButton.addEventListener('click', renderRows);
     startDateInput.addEventListener('change', renderRows);
@@ -366,6 +434,10 @@
         slotLengthInput.addEventListener('input', calculateSlots);
         slotLengthInput.addEventListener('change', calculateSlots);
     }
+    if (clientsperslot) {
+        clientsperslot.addEventListener('input', calculateSlots);
+        clientsperslot.addEventListener('change', calculateSlots);
+    }
 
     if (startDateInput.value && endDateInput.value) {
         renderRows();

Web/templates/upload_admin.html

@@ -954,7 +954,7 @@
                 <div class="isbn-input-group">
                     <input type="text" id="isbn" name="isbn" placeholder="ISBN oder Barcode eingeben..." required>
                     <button type="button" id="scan-isbn-btn" class="fetch-isbn-button">Barcode scannen</button>
-                    <button type="button" class="fetch-isbn-button" onclick="fetchBookInfo('upload')">Bild abrufen</button>
+                    <button type="button" class="fetch-isbn-button" onclick="fetchBookInfo('upload')">Informationen abrufen</button>
                 </div>
                 <div id="isbn-scanner" style="width:100%; max-width:520px; display:none; margin-top:10px;"></div>
                 <small id="isbn-scan-status" style="display:block; color:#666; margin-top:6px;">Scannen oder manuell eingeben. Gültige ISBNs helfen beim Abruf von Buchdaten, andere Codes werden trotzdem akzeptiert.</small>