made changes in chat

backend/blueprints/chat/__init__.py

@@ -1,66 +1,142 @@
-from flask import Blueprint, request, jsonify
-from uuid import UUID
-from db.model import db, User, Course, Enrollment
+from flask import Blueprint, request, jsonify, current_app, g
+from db.model import User, Course, Enrollment, Chat, db
+import uuid
+from sqlalchemy import select, and_
+from datetime import datetime
 
 chat = Blueprint('chat', __name__)
 
-@chat.route('/course/<uuid:course_id>/users', methods=['POST'])
-def get_users_assigned_to_course(course_id: UUID):
+@chat.route('/<uuid:course_id>/messages', methods=['GET'])
+def get_course_messages(course_id: uuid.UUID):
     """
-    Fetch all users assigned to a specific course.
-    :param course_id: ID of the course to fetch users for (UUID).
-    :return: JSON response with users assigned to the course.
+    Fetch chat messages for a specific course.
+    Only enrolled users can access the messages.
     """
     try:
-        # Query the course to ensure it exists
-        course = Course.query.get(course_id)
-        if not course:
-            return jsonify({"error": "Course not found."}), 404
-
-        # Get the list of users assigned to the course
-        users = User.query.filter(User.enrollments.any(course_id=course_id)).all()
-
-        # Prepare the response data
-        user_data = [
-            {
-                "id": user.id,
-                "email": user.email,
-                "username": user.username,
-                "firstName": user.firstName,
-                "lastName": user.lastName,
-            }
-            for user in users
-        ]
-
-        return jsonify({"course": course.name, "users": user_data}), 200
-    except Exception as e:
-        return jsonify({"error": f"An error occurred: {str(e)}"}), 500
+        current_user: User = g.current_user
+        
+        # Verify user's enrollment
+        enrollment = db.session.execute(
+            select(Enrollment).where(
+                and_(
+                    Enrollment.courseID == course_id,
+                    Enrollment.userID == current_user.id
+                )
+            )
+        ).scalar()
+        
+        if not enrollment:
+            return jsonify({'message': 'You are not enrolled in this course'}), 401
+            
+        # Get chat messages for the course
+        messages = db.session.execute(
+            select(Chat)
+            .where(Chat.courseID == course_id)
+            .order_by(Chat.chatDate.desc())
+        ).scalars()
+        
+        # Format messages
+        chat_messages = [{
+            'id': str(msg.id),
+            'text': msg.textContent,
+            'userId': str(msg.userID),
+            'username': msg.user.username,
+            'timestamp': msg.chatDate.isoformat()
+        } for msg in messages]
+        
+        return jsonify({'messages': chat_messages}), 200
         
+    except Exception as e:
+        return jsonify({'message': f'An error occurred: {str(e)}'}), 500
 
-@chat.route('/course/<uuid:course_id>/chat', methods=['POST'])
-def join_chat(course_id: UUID):
+@chat.route('/<uuid:course_id>/send', methods=['POST'])
+def send_message(course_id: uuid.UUID):
     """
-    Allow users to join the chat only if they are enrolled in the course.
-    :param course_id: ID of the course (UUID).
-    :return: JSON response indicating whether the user can join or not.
+    Send a new chat message in a course.
+    Only enrolled users can send messages.
     """
     try:
-        # Get the user from the request (assume user_id is passed in the request body)
-        user_id = request.json.get('user_id')
-        if not user_id:
-            return jsonify({"error": "User ID is required."}), 400
-
-        # Query the user and ensure they exist
-        user = User.query.get(user_id)
-        if not user:
-            return jsonify({"error": "User not found."}), 404
-
-        # Check if the user is enrolled in the course
-        enrollment = Enrollment.query.filter_by(userID=user_id, courseID=course_id).first()
+        current_user: User = g.current_user
+        message_text = request.json.get('message')
+        
+        if not message_text or not message_text.strip():
+            return jsonify({'message': 'Message content is required'}), 400
+            
+        # Verify user's enrollment
+        enrollment = db.session.execute(
+            select(Enrollment).where(
+                and_(
+                    Enrollment.courseID == course_id,
+                    Enrollment.userID == current_user.id
+                )
+            )
+        ).scalar()
+        
         if not enrollment:
-            return jsonify({"error": "User is not enrolled in this course."}), 403
+            return jsonify({'message': 'You are not enrolled in this course'}), 401
+            
+        # Create new chat message
+        new_message = Chat(
+            textContent=message_text,
+            userID=current_user.id,
+            courseID=course_id,
+            chatDate=datetime.now()
+        )
+        
+        db.session.add(new_message)
+        
+        # Update last activity in enrollment
+        enrollment.lastActivity = datetime.now()
+        
+        db.session.commit()
+        
+        return jsonify({
+            'message': 'Message sent successfully',
+            'messageId': str(new_message.id),
+            'timestamp': new_message.chatDate.isoformat()
+        }), 201
+        
+    except Exception as e:
+        db.session.rollback()
+        return jsonify({'message': f'An error occurred: {str(e)}'}), 500
+
+@chat.route('/<uuid:course_id>/participants', methods=['GET'])
+def get_chat_participants(course_id: uuid.UUID):
+    """
+    Get list of active participants in a course chat.
+    Returns only enrolled users with recent activity.
+    """
+    try:
+        current_user: User = g.current_user
+        
+        # Verify requesting user's enrollment
+        user_enrollment = db.session.execute(
+            select(Enrollment).where(
+                and_(
+                    Enrollment.courseID == course_id,
+                    Enrollment.userID == current_user.id
+                )
+            )
+        ).scalar()
+        
+        if not user_enrollment:
+            return jsonify({'message': 'You are not enrolled in this course'}), 401
+            
+        # Get enrolled users
+        enrollments = db.session.execute(
+            select(Enrollment)
+            .where(Enrollment.courseID == course_id)
+            .join(User)
+        ).scalars()
+        
+        # Return participant information
+        participants = [{
+            'id': str(enrollment.userID),
+            'username': enrollment.user.username,
+            'lastActivity': enrollment.lastActivity.isoformat()
+        } for enrollment in enrollments]
+        
+        return jsonify({'participants': participants}), 200
         
-        # If enrolled, allow the user to join the chat
-        return jsonify({"message": f"User {user.username} is enrolled in the course and can join the chat."}), 200
     except Exception as e:
-        return jsonify({"error": f"An error occurred: {str(e)}"}), 500
+        return jsonify({'message': f'An error occurred: {str(e)}'}), 500