Vorschau erstellt

app/mailmerge/views.py

@@ -1,16 +1,21 @@
+import logging
 from pathlib import Path
 
+from django.contrib import messages
 from django.contrib.auth.decorators import login_required
 from django.http import FileResponse, Http404, HttpResponse
 from django.shortcuts import get_object_or_404, redirect, render
 from django.urls import reverse
-from django.views.decorators.http import require_http_methods
+from django.views.decorators.http import require_http_methods, require_POST
 
 from .forms import LetterTemplateForm, MailMergeJobForm
 from .models import LetterTemplate, MailMergeJob
 from .services.docx_renderer import extract_placeholders
+from .services.preview import PreviewError, build_preview
 from .tasks import run_mailmerge
 
+logger = logging.getLogger(__name__)
+
 
 @login_required
 def dashboard(request):
@@ -54,6 +59,45 @@ def job_create(request):
     return render(request, "mailmerge/job_form.html", {"form": form})
 
 
+@login_required
+@require_POST
+def job_preview(request):
+    """Rendert nur die erste CSV-Zeile gegen das gewählte Template und
+    liefert das PDF inline aus. Persistiert nichts."""
+    form = MailMergeJobForm(request.POST, request.FILES)
+    if not form.is_valid():
+        # Form-Errors zurück ins Hauptformular leiten
+        return render(request, "mailmerge/job_form.html",
+                      {"form": form, "preview_error": None})
+
+    template = form.cleaned_data["template"]
+    csv_upload = form.cleaned_data["recipients_csv"]
+
+    try:
+        result = build_preview(
+            template_path=Path(template.file.path),
+            csv_file=csv_upload,
+        )
+    except PreviewError as exc:
+        messages.error(request, str(exc))
+        return render(request, "mailmerge/job_form.html",
+                      {"form": form, "preview_error": str(exc)})
+    except Exception as exc:  # noqa: BLE001 – defensiv, breite Fehlerklasse von LibreOffice
+        logger.exception("Preview-Render fehlgeschlagen")
+        messages.error(
+            request,
+            "Vorschau konnte nicht erstellt werden: " + str(exc),
+        )
+        return render(request, "mailmerge/job_form.html",
+                      {"form": form, "preview_error": str(exc)})
+
+    response = HttpResponse(result.pdf_bytes, content_type="application/pdf")
+    response["Content-Disposition"] = 'inline; filename="vorschau.pdf"'
+    response["X-Preview-Placeholders"] = ",".join(result.placeholders)
+    response["X-Preview-Extra-Columns"] = ",".join(result.extra_columns)
+    return response
+
+
 @login_required
 def job_detail(request, pk):
     job = get_object_or_404(