Implement newsletter scheduling features

- Added a background scheduler to manage newsletter dispatch based on user-defined settings.
- Enhanced the SMTP settings to include scheduling options such as frequency, time, and specific weekdays.
- Updated the dashboard UI to allow users to configure scheduling preferences for automated newsletter sending.
- Modified the newsletter generation logic to accommodate new scheduling parameters and ensure proper content delivery.

app/services/smtp_sender.py

@@ -20,11 +20,53 @@ def get_smtp_settings(db: Session) -> dict[str, str]:
         "from_email": get_config(db, "smtp.from_email", ""),
         "use_tls": get_config(db, "smtp.use_tls", "true"),
         "recipients": get_config(db, "smtp.recipients", ""),
+        # Zeitplan
+        "schedule_enabled": get_config(db, "smtp.schedule_enabled", "false"),
+        "schedule_frequency": get_config(db, "smtp.schedule_frequency", "monthly"),
         "schedule_time": get_config(db, "smtp.schedule_time", "08:00"),
+        "schedule_weekdays": get_config(db, "smtp.schedule_weekdays", "0"),
+        "schedule_dom": get_config(db, "smtp.schedule_dom", "1"),
         "last_scheduled_date": get_config(db, "smtp.last_scheduled_date", ""),
+        # Generierungs-Vorgaben für den geplanten Versand
+        "gen_period": get_config(db, "smtp.gen_period", "last_month"),
+        "gen_days": get_config(db, "smtp.gen_days", "30"),
+        "gen_article_type": get_config(db, "smtp.gen_article_type", "new"),
+        "gen_category": get_config(db, "smtp.gen_category", ""),
     }
 
 
+def schedule_is_due(settings: dict[str, str], now: datetime) -> bool:
+    """Prüft, ob laut Zeitplan jetzt ein Versand fällig ist (mit Tages-Dedupe)."""
+    if settings["enabled"].lower() != "true":
+        return False
+    if (settings.get("schedule_enabled") or "false").lower() != "true":
+        return False
+    freq = (settings.get("schedule_frequency") or "off").lower()
+    if freq == "off":
+        return False
+
+    schedule_time = settings.get("schedule_time") or "08:00"
+    if now.strftime("%H:%M") < schedule_time:
+        return False
+
+    today = now.strftime("%Y-%m-%d")
+    if settings.get("last_scheduled_date") == today:
+        return False
+
+    if freq == "daily":
+        return True
+    if freq == "weekly":
+        weekdays = {d.strip() for d in (settings.get("schedule_weekdays") or "").split(",") if d.strip() != ""}
+        return str(now.weekday()) in weekdays
+    if freq == "monthly":
+        try:
+            dom = int(settings.get("schedule_dom") or "1")
+        except ValueError:
+            dom = 1
+        return now.day == max(1, min(dom, 28))
+    return False
+
+
 def send_newsletter(
     db: Session,
     subject: str,
@@ -67,22 +109,10 @@ def send_newsletter(
         return "failed", detail
 
 
-def run_scheduled_send_if_due(db: Session, subject: str, html_content: str, text_content: str) -> None:
-    settings = get_smtp_settings(db)
-    if settings["enabled"].lower() != "true":
-        return
-    now = datetime.now()
-    schedule_time = settings["schedule_time"] or "08:00"
-    if now.strftime("%H:%M") < schedule_time:
-        return
-    today = now.strftime("%Y-%m-%d")
-    if settings["last_scheduled_date"] == today:
-        return
-    recipients = [r.strip() for r in settings["recipients"].split(",") if r.strip()]
-    send_newsletter(db, subject, html_content, text_content, recipients, scheduled=True)
+def mark_scheduled_sent(db: Session, now: datetime) -> None:
     from app.services.config_store import set_config
 
-    set_config(db, "smtp.last_scheduled_date", today)
+    set_config(db, "smtp.last_scheduled_date", now.strftime("%Y-%m-%d"))
 
 
 def _log(db: Session, subject: str, recipients: Sequence[str], status: str, detail: str, scheduled: bool) -> None: