feat(ParticipantController, ParticipantModel, ParticipantRoutes, DiaryParticipantsPanel, i18n): implement participant status management and UI updates

- Added functionality to update participant attendance status, allowing for 'excused' and 'cancelled' states.
- Enhanced the participant model to include a default attendance status and validation for status values.
- Updated participant routes to support status updates and integrated new status handling in the participant controller.
- Modified the DiaryParticipantsPanel to visually indicate participant status and added a toggle for changing status.
- Expanded localization files to include new keys for participant status, improving accessibility for users in both English and German.

backend/controllers/participantController.js

@@ -1,13 +1,17 @@
 import Participant from '../models/Participant.js';
 import DiaryDates from '../models/DiaryDates.js';
+import DiaryMemberActivity from '../models/DiaryMemberActivity.js';
 import { devLog } from '../utils/logger.js';
 import { emitParticipantAdded, emitParticipantRemoved, emitParticipantUpdated } from '../services/socketService.js';
+
+const PARTICIPANT_ATTRIBUTES = ['id', 'diaryDateId', 'memberId', 'attendanceStatus', 'groupId', 'notes', 'createdAt', 'updatedAt'];
+
 export const getParticipants = async (req, res) => {
     try {
         const { dateId } = req.params;
         const participants = await Participant.findAll({ 
             where: { diaryDateId: dateId },
-            attributes: ['id', 'diaryDateId', 'memberId', 'groupId', 'notes', 'createdAt', 'updatedAt']
+            attributes: PARTICIPANT_ATTRIBUTES
         });
         res.status(200).json(participants);
     } catch (error) {
@@ -68,12 +72,22 @@ export const updateParticipantGroup = async (req, res) => {
 export const addParticipant = async (req, res) => {
     try {
         const { diaryDateId, memberId } = req.body;
-        const participant = await Participant.create({ diaryDateId, memberId });
+        const [participant, created] = await Participant.findOrCreate({
+            where: { diaryDateId, memberId },
+            defaults: { diaryDateId, memberId, attendanceStatus: 'present' }
+        });
+
+        participant.attendanceStatus = 'present';
+        await participant.save();
         
         // Hole DiaryDate für clubId
         const diaryDate = await DiaryDates.findByPk(diaryDateId);
         if (diaryDate?.clubId) {
-            emitParticipantAdded(diaryDate.clubId, diaryDateId, participant);
+            if (created) {
+                emitParticipantAdded(diaryDate.clubId, diaryDateId, participant);
+            } else {
+                emitParticipantUpdated(diaryDate.clubId, diaryDateId, participant);
+            }
         }
         
         res.status(201).json(participant);
@@ -90,6 +104,15 @@ export const removeParticipant = async (req, res) => {
         // Hole DiaryDate für clubId vor dem Löschen
         const diaryDate = await DiaryDates.findByPk(diaryDateId);
         const clubId = diaryDate?.clubId;
+
+        const participant = await Participant.findOne({
+            where: { diaryDateId, memberId },
+            attributes: ['id']
+        });
+
+        if (participant) {
+            await DiaryMemberActivity.destroy({ where: { participantId: participant.id } });
+        }
         
         await Participant.destroy({ where: { diaryDateId, memberId } });
         
@@ -104,3 +127,53 @@ export const removeParticipant = async (req, res) => {
         res.status(500).json({ error: 'Fehler beim Entfernen des Teilnehmers' });
     }
 };
+
+export const updateParticipantStatus = async (req, res) => {
+    try {
+        const { dateId, memberId } = req.params;
+        const { attendanceStatus } = req.body;
+
+        if (!['excused', 'cancelled'].includes(attendanceStatus)) {
+            return res.status(400).json({ error: 'Ungültiger Teilnehmerstatus' });
+        }
+
+        const diaryDate = await DiaryDates.findByPk(dateId);
+        if (!diaryDate) {
+            return res.status(404).json({ error: 'Trainingstag nicht gefunden' });
+        }
+
+        const [participant] = await Participant.findOrCreate({
+            where: {
+                diaryDateId: dateId,
+                memberId
+            },
+            defaults: {
+                diaryDateId: dateId,
+                memberId,
+                attendanceStatus
+            }
+        });
+
+        participant.attendanceStatus = attendanceStatus;
+        participant.groupId = null;
+        await participant.save();
+        await DiaryMemberActivity.destroy({ where: { participantId: participant.id } });
+
+        const updatedParticipant = await Participant.findOne({
+            where: {
+                diaryDateId: dateId,
+                memberId
+            },
+            attributes: PARTICIPANT_ATTRIBUTES
+        });
+
+        if (diaryDate.clubId && updatedParticipant) {
+            emitParticipantUpdated(diaryDate.clubId, dateId, updatedParticipant);
+        }
+
+        res.status(200).json(updatedParticipant || participant);
+    } catch (error) {
+        devLog(error);
+        res.status(500).json({ error: 'Fehler beim Aktualisieren des Teilnehmerstatus' });
+    }
+};