feat: CSV-Import ueber bestehende Pipeline mit dreiwertiger Saldo-Pruefung

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

finance/app/routers/imports.py

@@ -11,7 +11,7 @@ from app.auth import require_auth
 from app.config import get_settings
 from app.db import get_session
 from app.models.tables import Statement, Transaction
-from app.services.importer import process_pdf
+from app.services.importer import process_file
 
 router = APIRouter(prefix="/api/imports", tags=["imports"],
                    dependencies=[Depends(require_auth)])
@@ -50,22 +50,22 @@ class TransactionOut(BaseModel):
 class PreviewOut(BaseModel):
     statement: StatementOut
     transactions: list[TransactionOut]
-    balance_ok: bool
+    balance_ok: bool | None
     duplicates: int
 
 
 @router.post("/upload", response_model=StatementOut, status_code=201)
 def upload(file: UploadFile, session: Session = Depends(get_session)):
     safe_name = Path(file.filename or "upload.pdf").name
-    if not safe_name or not safe_name.lower().endswith(".pdf"):
-        raise HTTPException(400, "Nur PDF-Dateien")
+    if not safe_name or not safe_name.lower().endswith((".pdf", ".csv")):
+        raise HTTPException(400, "Nur PDF- oder CSV-Dateien")
     settings = get_settings()
     inbox_dir = settings.inbox_dir
     inbox_dir.mkdir(parents=True, exist_ok=True)
     dest = inbox_dir / safe_name
     with dest.open("wb") as f:
         f.write(file.file.read())
-    stmt = process_pdf(session, dest)
+    stmt = process_file(session, dest)
     return StatementOut.model_validate(stmt)
 
 
@@ -74,9 +74,10 @@ def scan_inbox(session: Session = Depends(get_session)):
     settings = get_settings()
     inbox_dir = settings.inbox_dir
     inbox_dir.mkdir(parents=True, exist_ok=True)
+    paths = sorted(inbox_dir.glob("*.pdf")) + sorted(inbox_dir.glob("*.csv"))
     results = []
-    for path in sorted(inbox_dir.glob("*.pdf")):
-        stmt = process_pdf(session, path)
+    for path in paths:
+        stmt = process_file(session, path)
         results.append(StatementOut.model_validate(stmt))
     return results
 
@@ -96,11 +97,17 @@ def preview(statement_id: int, session: Session = Depends(get_session)):
         select(Transaction).where(Transaction.statement_id == statement_id)
         .order_by(Transaction.booking_date, Transaction.id)
     ).scalars().all()
-    balance_ok = (
-        stmt.opening_balance is not None and stmt.closing_balance is not None
-        and (stmt.opening_balance + sum((t.amount for t in txs), Decimal("0"))
-             - stmt.closing_balance) == 0
-    )
+    # Dreiwertig (Ausbaustufe 3 Task 3): manche CSV-Formate (z.B. HVB, DKB)
+    # liefern keine Saldodaten - None statt False, damit die Vorschau nicht
+    # faelschlich einen Saldo-Fehler anzeigt, wo schlicht keine Pruefung
+    # moeglich ist.
+    if stmt.opening_balance is None or stmt.closing_balance is None:
+        balance_ok = None
+    else:
+        balance_ok = (
+            stmt.opening_balance + sum((t.amount for t in txs), Decimal("0"))
+            - stmt.closing_balance
+        ) == 0
     duplicates = sum(1 for t in txs if t.is_duplicate)
     return PreviewOut(
         statement=StatementOut.model_validate(stmt),