Copy directly-sent e-mails to an IMAP Sent folder, with a live folder picker

A raw SMTP send has no server-side "Sent" copy on its own (unlike IMAP
drafts, which are inherently server-side) -- add an opt-in checkbox plus a
configurable target folder so directly sent Mahnungen/SEPA-info-mails still
show up in the account's Gesendet/Sent folder like a normal mail client
would leave them. Applies only to "send" delivery; drafts already live on
the server by definition.

Both the Entwürfe- and Gesendet-folder fields are now editable comboboxes:
a new "Ordnerliste laden" button fetches the real folder list from the IMAP
server (needs working credentials first) via LIST, decoding folder names
from modified UTF-7 (RFC 3501) so names like "Entwürfe" render correctly
instead of as "Entw&APw-rfe". Free text still works -- ensure_imap_folder()
creates the folder on first use if it doesn't exist yet, checked once per
batch rather than before every single message.

mail_delivery.append_to_imap_drafts() became the more general
append_message(client, content, folder=, flags=), reused for both the
\Draft and \Seen cases.

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

src/ccma/services/mail_delivery.py

@@ -1,6 +1,9 @@
 from __future__ import annotations
 
+import base64
+import binascii
 import imaplib
+import re
 import smtplib
 import ssl
 from collections.abc import Iterator
@@ -90,16 +93,127 @@ def send_via_smtp(client: smtplib.SMTP, message_bytes: bytes) -> None:
         raise RepositoryError(f"E-Mail konnte nicht versandt werden: {exc}") from exc
 
 
-def append_to_imap_drafts(client: imaplib.IMAP4, message_bytes: bytes, *, folder: str) -> None:
+def append_message(client: imaplib.IMAP4, message_bytes: bytes, *, folder: str, flags: str) -> None:
     try:
-        status, response = client.append(folder, r"(\Draft)", None, message_bytes)
+        status, response = client.append(_encode_imap_utf7(folder), flags, None, message_bytes)
     except (OSError, imaplib.IMAP4.error) as exc:
-        raise RepositoryError(f"E-Mail konnte nicht als Entwurf abgelegt werden: {exc}") from exc
+        raise RepositoryError(f"E-Mail konnte nicht in „{folder}“ abgelegt werden: {exc}") from exc
     if status != "OK":
         detail = response[0].decode("utf-8", "replace") if response and response[0] else status
         raise RepositoryError(f"IMAP-Server hat die Ablage im Ordner „{folder}“ abgelehnt: {detail}")
 
 
+def ensure_imap_folder(client: imaplib.IMAP4, folder: str) -> None:
+    """Creates the folder on the server if it doesn't exist yet -- lets someone type
+    a not-yet-existing Entwürfe/Gesendet folder name and have it just appear, instead
+    of every append failing until it's created by hand in a separate mail client."""
+    encoded = _encode_imap_utf7(folder)
+    try:
+        status, _response = client.select(encoded, readonly=True)
+    except (OSError, imaplib.IMAP4.error) as exc:
+        raise RepositoryError(f"IMAP-Ordner „{folder}“ konnte nicht geprüft werden: {exc}") from exc
+    if status == "OK":
+        return
+    try:
+        status, response = client.create(encoded)
+    except (OSError, imaplib.IMAP4.error) as exc:
+        raise RepositoryError(f"IMAP-Ordner „{folder}“ konnte nicht angelegt werden: {exc}") from exc
+    if status != "OK":
+        detail = response[0].decode("utf-8", "replace") if response and response[0] else status
+        raise RepositoryError(f"IMAP-Ordner „{folder}“ konnte nicht angelegt werden: {detail}")
+
+
+_LIST_RESPONSE_RE = re.compile(
+    rb'^\((?P<flags>[^)]*)\)\s+(?:"(?P<qdelim>[^"]*)"|(?P<delim>\S+))\s+(?P<name>.+)$'
+)
+
+
+def list_imap_folders(settings: dict) -> list[str]:
+    """Human-readable (decoded) folder names for the Options dialog's folder picker
+    -- fetched live from the server, so it only works once credentials are entered."""
+    with imap_session(settings) as client:
+        try:
+            status, response = client.list()
+        except (OSError, imaplib.IMAP4.error) as exc:
+            raise RepositoryError(f"Ordnerliste konnte nicht abgerufen werden: {exc}") from exc
+        if status != "OK":
+            raise RepositoryError("Ordnerliste konnte nicht abgerufen werden.")
+        folders = []
+        for raw in response or []:
+            if not raw:
+                continue
+            name = _parse_list_response(raw)
+            if name:
+                folders.append(name)
+        return folders
+
+
+def _parse_list_response(raw: bytes) -> str | None:
+    match = _LIST_RESPONSE_RE.match(raw)
+    if not match:
+        return None
+    name = match.group("name").decode("utf-8", "replace").strip()
+    if name.startswith('"') and name.endswith('"') and len(name) >= 2:
+        name = name[1:-1]
+    return _decode_imap_utf7(name)
+
+
+def _decode_imap_utf7(value: str) -> str:
+    # Modified UTF-7 (RFC 3501 5.1.3): "&" takes the role of "+", and "," takes the
+    # role of "/" inside the base64 run; "&-" is a literal ampersand.
+    if "&" not in value:
+        return value
+    result: list[str] = []
+    index = 0
+    length = len(value)
+    while index < length:
+        char = value[index]
+        if char != "&":
+            result.append(char)
+            index += 1
+            continue
+        end = value.find("-", index + 1)
+        if end == -1:
+            end = length
+        chunk = value[index + 1 : end]
+        if chunk == "":
+            result.append("&")
+        else:
+            base64_chunk = chunk.replace(",", "/")
+            base64_chunk += "=" * (-len(base64_chunk) % 4)
+            try:
+                result.append(base64.b64decode(base64_chunk).decode("utf-16-be"))
+            except (binascii.Error, UnicodeDecodeError):
+                result.append("&" + chunk + "-")
+        index = end + 1
+    return "".join(result)
+
+
+def _encode_imap_utf7(value: str) -> str:
+    if "&" not in value and all(32 <= ord(char) <= 126 for char in value):
+        return value
+    result: list[str] = []
+    index = 0
+    length = len(value)
+    while index < length:
+        char = value[index]
+        if char == "&":
+            result.append("&-")
+            index += 1
+            continue
+        if 32 <= ord(char) <= 126:
+            result.append(char)
+            index += 1
+            continue
+        start = index
+        while index < length and not (32 <= ord(value[index]) <= 126):
+            index += 1
+        chunk = value[start:index]
+        encoded = base64.b64encode(chunk.encode("utf-16-be")).decode("ascii").rstrip("=")
+        result.append("&" + encoded.replace("/", ",") + "-")
+    return "".join(result)
+
+
 def test_smtp_connection(settings: dict) -> None:
     with smtp_session(settings):
         pass

src/ccma/services/reminder_mail.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 import hashlib
 import os
 import re
+from contextlib import nullcontext
 from dataclasses import dataclass
 from datetime import datetime
 from email.message import EmailMessage
@@ -12,7 +13,13 @@ from pathlib import Path
 
 from ccma.domain.contributions import claim_balance
 from ccma.domain.dates import format_date_for_display
-from ccma.services.mail_delivery import append_to_imap_drafts, imap_session, send_via_smtp, smtp_session
+from ccma.services.mail_delivery import (
+    append_message,
+    ensure_imap_folder,
+    imap_session,
+    send_via_smtp,
+    smtp_session,
+)
 from ccma.storage.repository import MemberRepository, RepositoryError
 
 
@@ -178,12 +185,20 @@ def generate_and_send_reminder_mail(
                 export_temp.unlink(missing_ok=True)
             export_path = target
         elif delivery_mode == "send":
-            with smtp_session(repository.get_email_settings()) as client:
-                send_via_smtp(client, content)
+            settings = repository.get_email_settings()
+            sent_copy = imap_session(settings) if settings["imap_sent_enabled"] else nullcontext(None)
+            with smtp_session(settings) as smtp_client, sent_copy as imap_client:
+                send_via_smtp(smtp_client, content)
+                if imap_client is not None:
+                    ensure_imap_folder(imap_client, settings["imap_sent_folder"])
+                    append_message(
+                        imap_client, content, folder=settings["imap_sent_folder"], flags=r"(\Seen)"
+                    )
         else:
             settings = repository.get_email_settings()
             with imap_session(settings) as client:
-                append_to_imap_drafts(client, content, folder=settings["imap_drafts_folder"])
+                ensure_imap_folder(client, settings["imap_drafts_folder"])
+                append_message(client, content, folder=settings["imap_drafts_folder"], flags=r"(\Draft)")
         os.replace(archive_temp, archive_path)
     finally:
         archive_temp.unlink(missing_ok=True)

src/ccma/services/sepa_mail.py

@@ -10,7 +10,13 @@ from email.policy import SMTP
 from email.utils import format_datetime, make_msgid
 from pathlib import Path
 
-from ccma.services.mail_delivery import append_to_imap_drafts, imap_session, send_via_smtp, smtp_session
+from ccma.services.mail_delivery import (
+    append_message,
+    ensure_imap_folder,
+    imap_session,
+    send_via_smtp,
+    smtp_session,
+)
 from ccma.services.sepa import DirectDebit
 from ccma.storage.repository import MemberRepository, RepositoryError
 
@@ -105,18 +111,21 @@ def generate_debit_mails(
 ) -> tuple[list[GeneratedDebitMail], list[str]]:
     output: Path | None = None
     email_settings: dict | None = None
+    smtp_ctx = nullcontext(None)
+    imap_ctx = nullcontext(None)
     if delivery_mode == "local":
         if not output_directory:
             raise RepositoryError("Kein Zielordner für die lokale Ablage angegeben.")
         output = Path(output_directory)
         output.mkdir(parents=True, exist_ok=True)
-        session = nullcontext(None)
     elif delivery_mode == "send":
         email_settings = repository.get_email_settings()
-        session = smtp_session(email_settings)
+        smtp_ctx = smtp_session(email_settings)
+        if email_settings["imap_sent_enabled"]:
+            imap_ctx = imap_session(email_settings)
     elif delivery_mode == "drafts":
         email_settings = repository.get_email_settings()
-        session = imap_session(email_settings)
+        imap_ctx = imap_session(email_settings)
     else:
         raise RepositoryError(f"Unbekannter Versandmodus: {delivery_mode}")
 
@@ -126,9 +135,14 @@ def generate_debit_mails(
         raise RepositoryError("In den Optionen fehlt die Gläubiger-ID.")
     generated: list[GeneratedDebitMail] = []
     warnings: list[str] = []
-    # One connection is opened for the whole batch (a run can cover dozens of
-    # members) instead of reconnecting/re-authenticating per recipient.
-    with session as client:
+    # One connection (or two, for "send" with a Sent-folder copy) is opened for the
+    # whole batch -- a run can cover dozens of members -- instead of reconnecting/
+    # re-authenticating per recipient.
+    with smtp_ctx as smtp_client, imap_ctx as imap_client:
+        if delivery_mode == "drafts":
+            ensure_imap_folder(imap_client, email_settings["imap_drafts_folder"])
+        elif delivery_mode == "send" and imap_client is not None:
+            ensure_imap_folder(imap_client, email_settings["imap_sent_folder"])
         for debit in debits:
             member = repository.get_member(debit.member_id)
             if not member.email.strip():
@@ -156,9 +170,15 @@ def generate_debit_mails(
                 export_path = _available_path(output, filename)
                 export_path.write_bytes(content)
             elif delivery_mode == "send":
-                send_via_smtp(client, content)
+                send_via_smtp(smtp_client, content)
+                if imap_client is not None:
+                    append_message(
+                        imap_client, content, folder=email_settings["imap_sent_folder"], flags=r"(\Seen)"
+                    )
             else:
-                append_to_imap_drafts(client, content, folder=email_settings["imap_drafts_folder"])
+                append_message(
+                    imap_client, content, folder=email_settings["imap_drafts_folder"], flags=r"(\Draft)"
+                )
             try:
                 archive_path.write_bytes(content)
             except OSError:

src/ccma/storage/repository.py

@@ -154,6 +154,10 @@ DEFAULT_CONFIGURATION = {
         "imap_username": "",
         "imap_password": "",
         "imap_drafts_folder": "INBOX.Entwürfe",
+        # Sent-copy applies only to "send" (a direct SMTP send has no server-side
+        # "Sent" copy on its own, unlike drafts which are inherently server-side).
+        "imap_sent_enabled": False,
+        "imap_sent_folder": "INBOX.Sent",
     },
 }
 
@@ -2660,6 +2664,8 @@ class MemberRepository:
             "imap_drafts_folder": str(
                 settings.get("imap_drafts_folder", defaults["imap_drafts_folder"])
             ),
+            "imap_sent_enabled": bool(settings.get("imap_sent_enabled", defaults["imap_sent_enabled"])),
+            "imap_sent_folder": str(settings.get("imap_sent_folder", defaults["imap_sent_folder"])),
         }
 
     def save_email_settings(
@@ -2677,6 +2683,8 @@ class MemberRepository:
         imap_username: str,
         imap_password: str,
         imap_drafts_folder: str,
+        imap_sent_enabled: bool = False,
+        imap_sent_folder: str = "",
     ) -> None:
         if delivery_mode not in {"local", "send", "drafts", "ask"}:
             raise RepositoryError("Ungültiger Versandmodus.")
@@ -2688,6 +2696,10 @@ class MemberRepository:
             raise RepositoryError("Für den direkten Versand ist ein SMTP-Server erforderlich.")
         if delivery_mode in {"drafts", "ask"} and not imap_host.strip():
             raise RepositoryError("Für die Ablage als Entwurf ist ein IMAP-Server erforderlich.")
+        if imap_sent_enabled and not imap_host.strip():
+            raise RepositoryError(
+                "Für die Ablage im Gesendet-Ordner ist ein IMAP-Server erforderlich."
+            )
         for label, port in (("Der SMTP-Port", smtp_port), ("Der IMAP-Port", imap_port)):
             if port < 1 or port > 65535:
                 raise RepositoryError(f"{label} muss zwischen 1 und 65535 liegen.")
@@ -2705,6 +2717,8 @@ class MemberRepository:
             "imap_username": imap_username.strip(),
             "imap_password": imap_password,
             "imap_drafts_folder": imap_drafts_folder.strip() or "INBOX.Entwürfe",
+            "imap_sent_enabled": bool(imap_sent_enabled),
+            "imap_sent_folder": imap_sent_folder.strip() or "INBOX.Sent",
         }
         write_json_atomic(self.root / "repository.json", config)
 

src/ccma/ui/options_dialog.py

@@ -12,7 +12,7 @@ from ccma.services.intervals import (
     IntervalValidationError,
     normalize_anniversary_intervals,
 )
-from ccma.services.mail_delivery import test_imap_connection, test_smtp_connection
+from ccma.services.mail_delivery import list_imap_folders, test_imap_connection, test_smtp_connection
 from ccma.storage.repository import MemberRepository, RepositoryError, validate_member_number_pattern
 from ccma.ui.changelog_view import ChangelogView
 from ccma.ui.icons import IconStore
@@ -649,7 +649,7 @@ class OptionsDialog(tk.Toplevel):
             row=4, column=0, columnspan=4, sticky="w", pady=(8, 0)
         )
 
-        imap_frame = ttk.LabelFrame(parent, text="IMAP (für die Ablage als Entwurf)", padding=10)
+        imap_frame = ttk.LabelFrame(parent, text="IMAP (für Entwürfe & Gesendet)", padding=10)
         imap_frame.grid(row=3, column=0, columnspan=2, sticky="ew", pady=(16, 0))
         imap_frame.columnconfigure(1, weight=1)
         self.imap_host_var = tk.StringVar(value=email_settings["imap_host"])
@@ -660,6 +660,8 @@ class OptionsDialog(tk.Toplevel):
         self.imap_username_var = tk.StringVar(value=email_settings["imap_username"])
         self.imap_password_var = tk.StringVar(value=email_settings["imap_password"])
         self.imap_drafts_folder_var = tk.StringVar(value=email_settings["imap_drafts_folder"])
+        self.imap_sent_enabled_var = tk.BooleanVar(value=email_settings["imap_sent_enabled"])
+        self.imap_sent_folder_var = tk.StringVar(value=email_settings["imap_sent_folder"])
         ttk.Label(imap_frame, text="Server").grid(row=0, column=0, sticky="w", pady=4, padx=(0, 8))
         ttk.Entry(imap_frame, textvariable=self.imap_host_var).grid(
             row=0, column=1, sticky="ew", pady=4, padx=(0, 8)
@@ -685,12 +687,33 @@ class OptionsDialog(tk.Toplevel):
             row=3, column=1, columnspan=3, sticky="ew", pady=4
         )
         ttk.Label(imap_frame, text="Entwürfe-Ordner").grid(row=4, column=0, sticky="w", pady=4, padx=(0, 8))
-        ttk.Entry(imap_frame, textvariable=self.imap_drafts_folder_var).grid(
-            row=4, column=1, columnspan=3, sticky="ew", pady=4
-        )
-        ttk.Button(imap_frame, text="Verbindung testen", command=self._test_imap_connection).grid(
-            row=5, column=0, columnspan=4, sticky="w", pady=(8, 0)
+        self.imap_drafts_folder_combo = ttk.Combobox(imap_frame, textvariable=self.imap_drafts_folder_var)
+        self.imap_drafts_folder_combo.grid(row=4, column=1, columnspan=3, sticky="ew", pady=4)
+        ttk.Checkbutton(
+            imap_frame,
+            text="Direkt versandte Mahnungen/Info-Mails zusätzlich in einen Gesendet-Ordner ablegen",
+            variable=self.imap_sent_enabled_var,
+        ).grid(row=5, column=0, columnspan=4, sticky="w", pady=(8, 4))
+        ttk.Label(imap_frame, text="Gesendet-Ordner").grid(row=6, column=0, sticky="w", pady=4, padx=(0, 8))
+        self.imap_sent_folder_combo = ttk.Combobox(imap_frame, textvariable=self.imap_sent_folder_var)
+        self.imap_sent_folder_combo.grid(row=6, column=1, columnspan=3, sticky="ew", pady=4)
+        buttons_row = ttk.Frame(imap_frame)
+        buttons_row.grid(row=7, column=0, columnspan=4, sticky="w", pady=(8, 0))
+        ttk.Button(buttons_row, text="Verbindung testen", command=self._test_imap_connection).pack(
+            side="left", padx=(0, 8)
         )
+        ttk.Button(buttons_row, text="Ordnerliste laden", command=self._load_imap_folders).pack(side="left")
+        ttk.Label(
+            imap_frame,
+            text=(
+                "„Ordnerliste laden“ ruft die Ordner live vom Server ab (Zugangsdaten oben müssen "
+                "dafür bereits ausgefüllt sein) und füllt beide Dropdowns; freie Eingabe bleibt "
+                "möglich -- ein dabei angegebener, noch nicht vorhandener Ordner wird bei der "
+                "nächsten Ablage automatisch angelegt."
+            ),
+            style="Muted.TLabel",
+            wraplength=660,
+        ).grid(row=8, column=0, columnspan=4, sticky="w", pady=(6, 0))
 
         ttk.Label(
             parent,
@@ -717,6 +740,8 @@ class OptionsDialog(tk.Toplevel):
             "imap_username": self.imap_username_var.get(),
             "imap_password": self.imap_password_var.get(),
             "imap_drafts_folder": self.imap_drafts_folder_var.get(),
+            "imap_sent_enabled": self.imap_sent_enabled_var.get(),
+            "imap_sent_folder": self.imap_sent_folder_var.get(),
         }
 
     def _test_smtp_connection(self) -> None:
@@ -747,6 +772,22 @@ class OptionsDialog(tk.Toplevel):
             return
         messagebox.showinfo("IMAP-Verbindung", "Verbindung und Anmeldung erfolgreich.", parent=self)
 
+    def _load_imap_folders(self) -> None:
+        settings = self._collect_email_settings()
+        try:
+            settings["imap_port"] = int(settings["imap_port"])
+        except ValueError:
+            messagebox.showerror("Ungültiger Port", "Der IMAP-Port muss eine ganze Zahl sein.", parent=self)
+            return
+        try:
+            folders = list_imap_folders(settings)
+        except RepositoryError as exc:
+            messagebox.showerror("Ordnerliste konnte nicht geladen werden", str(exc), parent=self)
+            return
+        self.imap_drafts_folder_combo.configure(values=folders)
+        self.imap_sent_folder_combo.configure(values=folders)
+        messagebox.showinfo("Ordnerliste geladen", f"{len(folders)} Ordner gefunden.", parent=self)
+
     def _choose_store(self) -> None:
         current = Path(self.store_var.get()).expanduser() if self.store_var.get().strip() else Path.home()
         initial = current if current.is_dir() else current.parent

tests/test_email_settings.py

@@ -12,6 +12,8 @@ def test_email_settings_default_to_local_delivery_for_new_repositories(tmp_path)
     assert settings["delivery_mode"] == "local"
     assert settings["smtp_host"] == ""
     assert settings["imap_host"] == ""
+    assert settings["imap_sent_enabled"] is False
+    assert settings["imap_sent_folder"] == "INBOX.Sent"
 
 
 def test_email_settings_round_trip_through_save_and_get(tmp_path) -> None:
@@ -31,6 +33,8 @@ def test_email_settings_round_trip_through_save_and_get(tmp_path) -> None:
         imap_username="board@example.org",
         imap_password="secret",
         imap_drafts_folder="INBOX.Entwürfe",
+        imap_sent_enabled=True,
+        imap_sent_folder="INBOX.Gesendet",
     )
 
     settings = repository.get_email_settings()
@@ -39,6 +43,31 @@ def test_email_settings_round_trip_through_save_and_get(tmp_path) -> None:
     assert settings["smtp_port"] == 587
     assert settings["smtp_password"] == "secret"
     assert settings["imap_drafts_folder"] == "INBOX.Entwürfe"
+    assert settings["imap_sent_enabled"] is True
+    assert settings["imap_sent_folder"] == "INBOX.Gesendet"
+
+
+def test_email_settings_sent_copy_requires_imap_host_even_in_send_only_mode(tmp_path) -> None:
+    repository = MemberRepository(tmp_path)
+    repository.initialize()
+
+    with pytest.raises(RepositoryError, match="Gesendet-Ordner ist ein IMAP-Server erforderlich"):
+        repository.save_email_settings(
+            delivery_mode="send",
+            smtp_host="mail.example.org",
+            smtp_port=587,
+            smtp_security="starttls",
+            smtp_username="",
+            smtp_password="",
+            imap_host="",
+            imap_port=993,
+            imap_security="ssl",
+            imap_username="",
+            imap_password="",
+            imap_drafts_folder="",
+            imap_sent_enabled=True,
+            imap_sent_folder="",
+        )
 
 
 @pytest.mark.parametrize(

tests/test_mail_delivery.py

@@ -33,6 +33,7 @@ class _FakeSmtpClient:
 
 class _FakeImapClient:
     instances: list["_FakeImapClient"] = []
+    default_list_result: tuple = ("OK", [])
     error = Exception
 
     def __init__(self, host, port, **kwargs):
@@ -43,6 +44,11 @@ class _FakeImapClient:
         self.login_args: tuple | None = None
         self.appended: list[tuple] = []
         self.append_result = ("OK", [b"APPEND completed"])
+        self.selected: list[str] = []
+        self.select_result = ("OK", [b"1"])
+        self.created: list[str] = []
+        self.create_result = ("OK", [b"CREATE completed"])
+        self.list_result = _FakeImapClient.default_list_result
         _FakeImapClient.instances.append(self)
 
     def starttls(self, *args, **kwargs):
@@ -57,6 +63,20 @@ class _FakeImapClient:
         self.calls.append("append")
         return self.append_result
 
+    def select(self, folder, readonly=False):
+        self.selected.append(folder)
+        self.calls.append("select")
+        return self.select_result
+
+    def create(self, folder):
+        self.created.append(folder)
+        self.calls.append("create")
+        return self.create_result
+
+    def list(self):
+        self.calls.append("list")
+        return self.list_result
+
     def logout(self):
         self.calls.append("logout")
 
@@ -65,6 +85,7 @@ class _FakeImapClient:
 def _reset_fakes():
     _FakeSmtpClient.instances.clear()
     _FakeImapClient.instances.clear()
+    _FakeImapClient.default_list_result = ("OK", [])
     yield
 
 
@@ -118,23 +139,85 @@ def test_send_via_smtp_logs_in_and_sends_reusing_one_connection(monkeypatch) ->
     assert len(fake.sent_messages) == 2
 
 
-def test_append_to_imap_drafts_uses_configured_folder(monkeypatch) -> None:
+def test_append_message_uses_configured_folder_and_flags(monkeypatch) -> None:
     _patch_imap(monkeypatch)
     with mail_delivery.imap_session(IMAP_SETTINGS) as client:
-        mail_delivery.append_to_imap_drafts(client, MESSAGE, folder="INBOX.Entwürfe")
+        mail_delivery.append_message(client, MESSAGE, folder="INBOX.Entwürfe", flags=r"(\Draft)")
 
     fake = _FakeImapClient.instances[0]
     assert fake.login_args == ("board@example.org", "secret")
-    assert fake.appended == [("INBOX.Entwürfe", r"(\Draft)", None, MESSAGE)]
+    # The folder name travels the wire in modified UTF-7, not raw UTF-8.
+    assert fake.appended == [("INBOX.Entw&APw-rfe", r"(\Draft)", None, MESSAGE)]
     assert fake.calls == ["login", "append", "logout"]
 
 
-def test_append_to_imap_drafts_raises_on_rejected_status(monkeypatch) -> None:
+def test_append_message_raises_on_rejected_status(monkeypatch) -> None:
     _patch_imap(monkeypatch)
     with mail_delivery.imap_session(IMAP_SETTINGS) as client:
         client.append_result = ("NO", [b"Mailbox does not exist"])
         with pytest.raises(RepositoryError, match="Mailbox does not exist"):
-            mail_delivery.append_to_imap_drafts(client, MESSAGE, folder="Missing")
+            mail_delivery.append_message(client, MESSAGE, folder="Missing", flags=r"(\Seen)")
+
+
+def test_ensure_imap_folder_skips_creation_when_folder_already_exists(monkeypatch) -> None:
+    _patch_imap(monkeypatch)
+    with mail_delivery.imap_session(IMAP_SETTINGS) as client:
+        mail_delivery.ensure_imap_folder(client, "INBOX.Sent")
+
+    fake = _FakeImapClient.instances[0]
+    assert fake.selected == ["INBOX.Sent"]
+    assert fake.created == []
+
+
+def test_ensure_imap_folder_creates_missing_folder(monkeypatch) -> None:
+    _patch_imap(monkeypatch)
+    with mail_delivery.imap_session(IMAP_SETTINGS) as client:
+        client.select_result = ("NO", [b"Mailbox does not exist"])
+        mail_delivery.ensure_imap_folder(client, "Archiv.Neu")
+
+    fake = _FakeImapClient.instances[0]
+    assert fake.selected == ["Archiv.Neu"]
+    assert fake.created == ["Archiv.Neu"]
+
+
+def test_ensure_imap_folder_raises_when_creation_fails(monkeypatch) -> None:
+    _patch_imap(monkeypatch)
+    with mail_delivery.imap_session(IMAP_SETTINGS) as client:
+        client.select_result = ("NO", [b"no such mailbox"])
+        client.create_result = ("NO", [b"Permission denied"])
+        with pytest.raises(RepositoryError, match="Permission denied"):
+            mail_delivery.ensure_imap_folder(client, "Verboten")
+
+
+@pytest.mark.parametrize(
+    ("plain", "wire"),
+    [
+        ("INBOX", "INBOX"),
+        ("Entwürfe", "Entw&APw-rfe"),
+        ("INBOX.Entwürfe", "INBOX.Entw&APw-rfe"),
+        ("Test & Foo", "Test &- Foo"),
+    ],
+)
+def test_imap_utf7_round_trips(plain, wire) -> None:
+    assert mail_delivery._encode_imap_utf7(plain) == wire
+    assert mail_delivery._decode_imap_utf7(wire) == plain
+
+
+def test_list_imap_folders_parses_and_decodes_list_response(monkeypatch) -> None:
+    _patch_imap(monkeypatch)
+    _FakeImapClient.default_list_result = (
+        "OK",
+        [
+            rb'(\HasNoChildren) "." INBOX',
+            rb'(\HasNoChildren) "." INBOX.Entw&APw-rfe',
+            rb'(\HasNoChildren) "." "INBOX.Gesendete Objekte"',
+        ],
+    )
+
+    folders = mail_delivery.list_imap_folders(IMAP_SETTINGS)
+
+    assert folders == ["INBOX", "INBOX.Entwürfe", "INBOX.Gesendete Objekte"]
+    assert _FakeImapClient.instances[0].calls == ["login", "list", "logout"]
 
 
 def test_smtp_session_wraps_connection_errors(monkeypatch) -> None:

tests/test_reminder_mail.py

@@ -137,3 +137,66 @@ def test_reminder_mail_send_mode_delivers_via_smtp_without_local_file(tmp_path,
     assert len(sent) == 1
     data = repository.get_contributions(member.member_id)
     assert data.reminders[0]["status"] == "sent"
+
+
+def test_reminder_mail_send_mode_also_copies_to_sent_folder_when_enabled(tmp_path, monkeypatch):
+    import ccma.services.reminder_mail as reminder_mail_module
+
+    repository, member = _overdue_claim_repository(tmp_path / "store")
+    member.email = "reminder@example.org"
+    repository.save_member(member)
+    repository.save_email_settings(
+        delivery_mode="send",
+        smtp_host="mail.example.org",
+        smtp_port=587,
+        smtp_security="none",
+        smtp_username="",
+        smtp_password="",
+        imap_host="mail.example.org",
+        imap_port=993,
+        imap_security="ssl",
+        imap_username="",
+        imap_password="",
+        imap_drafts_folder="",
+        imap_sent_enabled=True,
+        imap_sent_folder="INBOX.Gesendet",
+    )
+    reminder = repository.create_reminder_draft(
+        member.member_id,
+        "claim-1",
+        level=1,
+        name="Zahlungserinnerung",
+        payment_deadline_days=14,
+    )
+
+    monkeypatch.setattr(
+        reminder_mail_module, "smtp_session", contextmanager(lambda settings: iter(["smtp-client"]))
+    )
+    monkeypatch.setattr(reminder_mail_module, "send_via_smtp", lambda client, content: None)
+    monkeypatch.setattr(
+        reminder_mail_module, "imap_session", contextmanager(lambda settings: iter(["imap-client"]))
+    )
+    ensured = []
+    appended = []
+    monkeypatch.setattr(
+        reminder_mail_module, "ensure_imap_folder", lambda client, folder: ensured.append((client, folder))
+    )
+    monkeypatch.setattr(
+        reminder_mail_module,
+        "append_message",
+        lambda client, content, *, folder, flags: appended.append((client, folder, flags)),
+    )
+
+    generate_and_send_reminder_mail(
+        repository,
+        member.member_id,
+        "claim-1",
+        reminder["reminder_id"],
+        delivery_mode="send",
+        sender_name="Verwaltung C3MA",
+        sender_email="verwaltung@example.org",
+        signature="Der Vorstand",
+    )
+
+    assert ensured == [("imap-client", "INBOX.Gesendet")]
+    assert appended == [("imap-client", "INBOX.Gesendet", r"(\Seen)")]

tests/test_sepa.py

@@ -290,3 +290,101 @@ def test_generated_mail_send_mode_reuses_one_smtp_connection_for_batch(tmp_path,
     assert generated[0].archive_path.is_file()
     assert len(connections_opened) == 1, "one connection should be reused for the whole batch"
     assert len(sent) == len(debits)
+
+
+def test_generated_mail_send_mode_copies_to_sent_folder_reusing_one_imap_connection(
+    tmp_path, monkeypatch
+):
+    import ccma.services.sepa_mail as sepa_mail_module
+
+    repository, ada = _repository(tmp_path)
+    second = repository.create_member(first_name="Grace", last_name="Hopper", member_number="C3-43")
+    second.status = "active"
+    second.email = "grace@example.org"
+    second.account_holder = "Grace Hopper"
+    second.iban = "DE89370400440532013000"
+    second.bic = "COBADEFFXXX"
+    second.mandate_reference = "MANDAT-43"
+    second.mandate_signed_at = "2025-01-10"
+    second.mandate_active = True
+    repository.save_member(second)
+    repository.save_contributions(
+        second.member_id,
+        ContributionData(
+            claims=[
+                {
+                    "claim_id": "due",
+                    "title": "Mitgliedsbeitrag 2026",
+                    "amount": "150.00",
+                    "due_date": "2026-01-31",
+                    "status": "open",
+                }
+            ]
+        ),
+    )
+    organization = repository.get_configuration()["organization"]
+    organization.update(
+        {
+            "name": "Chaos Computer Club Mannheim e.V.",
+            "email": "verwaltung@example.org",
+            "iban": "DE89370400440532013000",
+            "bic": "COBADEFFXXX",
+            "creditor_id": "DE98ZZZ09999999999",
+        }
+    )
+    repository.save_organization(organization)
+    repository.save_email_settings(
+        delivery_mode="send",
+        smtp_host="mail.example.org",
+        smtp_port=587,
+        smtp_security="none",
+        smtp_username="",
+        smtp_password="",
+        imap_host="mail.example.org",
+        imap_port=993,
+        imap_security="ssl",
+        imap_username="",
+        imap_password="",
+        imap_drafts_folder="",
+        imap_sent_enabled=True,
+        imap_sent_folder="INBOX.Gesendet",
+    )
+    debits, _warnings = pending_direct_debits(repository, due_until=date(2026, 12, 31))
+    assert len(debits) == 2
+
+    monkeypatch.setattr(
+        sepa_mail_module, "smtp_session", contextmanager(lambda settings: iter(["smtp-client"]))
+    )
+    monkeypatch.setattr(sepa_mail_module, "send_via_smtp", lambda client, content: None)
+    imap_connections = []
+
+    @contextmanager
+    def fake_imap_session(settings):
+        imap_connections.append(settings)
+        yield "imap-client"
+
+    monkeypatch.setattr(sepa_mail_module, "imap_session", fake_imap_session)
+    ensured = []
+    appended = []
+    monkeypatch.setattr(
+        sepa_mail_module, "ensure_imap_folder", lambda client, folder: ensured.append(folder)
+    )
+    monkeypatch.setattr(
+        sepa_mail_module,
+        "append_message",
+        lambda client, content, *, folder, flags: appended.append((client, folder, flags)),
+    )
+
+    generate_debit_mails(
+        repository,
+        debits,
+        collection_date=date(2026, 8, 3),
+        delivery_mode="send",
+        sender_name="Verwaltung C3MA",
+        sender_email="verwaltung@example.org",
+        signature="Der Vorstand",
+    )
+
+    assert len(imap_connections) == 1, "one IMAP connection should be reused for the whole batch"
+    assert ensured == ["INBOX.Gesendet"]
+    assert appended == [("imap-client", "INBOX.Gesendet", r"(\Seen)")] * 2