Feature/activity log

sage_validation/file_validator/views.py

 """Views for the file_validator app."""
 import csv
 import io
+from typing import ClassVar
 
 from django.http import HttpRequest, HttpResponse
 from django.shortcuts import render
 from django.urls import reverse_lazy
 from django.utils import timezone
 from rest_framework import status
+from rest_framework.permissions import IsAuthenticated
 from rest_framework.request import Request
 from rest_framework.response import Response
 from rest_framework.views import APIView
 
+from sage_validation.accounts.models import UserActivityLog
 from sage_validation.file_validator.forms import CSVUploadForm
 from sage_validation.file_validator.models import MeoCostCentres, XxData
 
@@ -28,6 +31,8 @@ def upload_page_view(request: HttpRequest) -> HttpResponse:
 class CSVUploadAPIView(APIView):
     """API view for uploading a CSV file."""
 
+    permission_classes: ClassVar[list] = [IsAuthenticated]
+
     def post(self, request: Request) -> Response:
         """Handle CSV upload and validation."""
         form = CSVUploadForm(data=request.data, files=request.FILES)
@@ -48,6 +53,7 @@ class CSVUploadAPIView(APIView):
 
         updated_data = self.update_fields(csv_data)
         request.session["validated_csv"] = updated_data
+        request.session["input_file_hash"] = UserActivityLog.generate_file_hash(csv_file)
         request.session.modified = True
 
         return Response({
@@ -98,16 +104,25 @@ class CSVExportAPIView(APIView):
     def get(self, request: Request) -> Response:
         """Return processed CSV as a downloadable response."""
         csv_data: list[dict[str, str]] = request.session.get("validated_csv", [])
+        input_file_hash: str = request.session.get("input_file_hash", "")
 
         if not csv_data:
             return Response({"status": "error", "message": "No data available for export."},
                             status=status.HTTP_400_BAD_REQUEST)
-
+        file_name = f"Validated_{csv_data[0].get('TransactionReference', 'file')}.csv"
         response = HttpResponse(content_type="text/csv")
-        response["Content-Disposition"] = 'attachment; filename="updated_file.csv"'
+        response["Content-Disposition"] = f"attachment; filename={file_name}"
 
         writer = csv.DictWriter(response, fieldnames=csv_data[0].keys())
         writer.writeheader()
         writer.writerows(csv_data)
-
+        # Log the user activity
+        UserActivityLog.objects.create(
+            user=request.user,
+            action="download",
+            name=file_name,
+            input_file_hash=input_file_hash,
+            output_file_hash=UserActivityLog.generate_file_hash(csv_data),
+            timestamp=timezone.now()
+        )
         return response