added backends, improved templating, rbac

server/app/mailer/sending/imap.py

@@ -26,6 +26,29 @@ class ImapAppendError(RuntimeError):
         self.temporary = temporary
 
 
+@dataclass(frozen=True, slots=True)
+class ImapLoginTestResult:
+    host: str
+    port: int
+    security: str
+    authenticated: bool
+
+
+@dataclass(frozen=True, slots=True)
+class ImapMailboxInfo:
+    name: str
+    flags: list[str]
+
+
+@dataclass(frozen=True, slots=True)
+class ImapFolderListResult:
+    host: str
+    port: int
+    security: str
+    folders: list[ImapMailboxInfo]
+    detected_sent_folder: str | None = None
+
+
 @dataclass(frozen=True, slots=True)
 class ImapAppendResult:
     host: str
@@ -83,43 +106,57 @@ def _decode_item(item: bytes | str | None) -> str:
     return item
 
 
-def _extract_mailbox_name(list_response_line: bytes | str) -> tuple[str, set[str]] | None:
-    """Best-effort parser for IMAP LIST response lines.
+def _unquote_imap_token(value: str) -> str:
+    value = value.strip()
+    if len(value) >= 2 and value[0] == '"' and value[-1] == '"':
+        value = value[1:-1]
+        value = value.replace('\\"', '"').replace('\\\\', '\\')
+    return value
 
-    Example lines:
-      (\\HasNoChildren \\Sent) "/" "Sent"
-      (\\HasNoChildren) "/" "Sent Items"
+
+def _extract_mailbox_name(list_response_line: bytes | str) -> tuple[str, set[str]] | None:
+    r"""Best-effort parser for IMAP LIST response lines.
+
+    RFC 3501 LIST responses contain attributes, hierarchy delimiter, then mailbox
+    name. Some servers quote both delimiter and mailbox::
+
+      (\HasNoChildren \Sent) "/" "Sent"
+
+    Others quote only the delimiter and leave the mailbox as an atom::
+
+      (\HasNoChildren \Sent) "/" Sent
+
+    The parser must therefore parse the delimiter token separately instead of
+    blindly taking the last quoted value.
     """
 
     line = _decode_item(list_response_line).strip()
-    flags_match = re.match(r"^\((?P<flags>[^)]*)\)\s+", line)
-    flags = set()
-    if flags_match:
-        flags = {part.lower() for part in flags_match.group("flags").split()}
+    match = re.match(
+        r'^\((?P<flags>[^)]*)\)\s+'
+        r'(?P<delimiter>"(?:[^"\\]|\\.)*"|NIL|[^\s]+)\s+'
+        r'(?P<mailbox>.+?)\s*$',
+        line,
+        re.IGNORECASE,
+    )
+    if match:
+        flags = {part.lower() for part in match.group("flags").split()}
+        mailbox = _unquote_imap_token(match.group("mailbox"))
+        if mailbox:
+            return mailbox, flags
+        return None
 
-    quoted = re.findall(r'"((?:[^"\\]|\\.)*)"', line)
-    if quoted:
-        # Usually: delimiter, mailbox. Take the last quoted token.
-        return quoted[-1].replace(r'\"', '"'), flags
-
-    # Fallback for unquoted final atom.
-    parts = line.split()
-    if parts:
-        return parts[-1], flags
+    # Fallback for non-standard server lines: prefer the final token.
+    parts = line.split(maxsplit=2)
+    if len(parts) >= 3:
+        flags_text = parts[0].strip("()")
+        flags = {part.lower() for part in flags_text.split()}
+        mailbox = _unquote_imap_token(parts[2])
+        if mailbox:
+            return mailbox, flags
     return None
 
 
-def discover_sent_folder(client: imaplib.IMAP4) -> str | None:
-    typ, data = client.list()
-    if typ != "OK" or not data:
-        return None
-
-    parsed: list[tuple[str, set[str]]] = []
-    for item in data:
-        extracted = _extract_mailbox_name(item)
-        if extracted:
-            parsed.append(extracted)
-
+def _detect_sent_folder(parsed: list[tuple[str, set[str]]]) -> str | None:
     for name, flags in parsed:
         if "\\sent" in flags or "\\sentmail" in flags:
             return name
@@ -140,6 +177,20 @@ def discover_sent_folder(client: imaplib.IMAP4) -> str | None:
     return None
 
 
+def discover_sent_folder(client: imaplib.IMAP4) -> str | None:
+    typ, data = client.list()
+    if typ != "OK" or not data:
+        return None
+
+    parsed: list[tuple[str, set[str]]] = []
+    for item in data:
+        extracted = _extract_mailbox_name(item)
+        if extracted:
+            parsed.append(extracted)
+
+    return _detect_sent_folder(parsed)
+
+
 def _effective_sent_folder(*, config: ImapConfig, requested_folder: str | None, client: imaplib.IMAP4) -> str:
     if requested_folder and requested_folder != "auto":
         return requested_folder
@@ -151,6 +202,63 @@ def _effective_sent_folder(*, config: ImapConfig, requested_folder: str | None,
     raise ImapConfigurationError("Could not discover Sent folder; configure delivery.imap_append_sent.folder or server.imap.sent_folder")
 
 
+def test_imap_login(*, imap_config: ImapConfig) -> ImapLoginTestResult:
+    """Open an IMAP connection and authenticate if credentials are configured.
+
+    This is a side-effect-free connection test for the WebUI. It does not select
+    a mailbox and does not append any message.
+    """
+
+    host, port = _require_imap_config(imap_config)
+    client = _open_imap(imap_config)
+    try:
+        return ImapLoginTestResult(
+            host=host,
+            port=port,
+            security=imap_config.security.value,
+            authenticated=bool(imap_config.username and imap_config.password),
+        )
+    finally:
+        try:
+            client.logout()
+        except Exception:
+            pass
+
+
+def list_imap_folders(*, imap_config: ImapConfig) -> ImapFolderListResult:
+    """Return folders visible through IMAP LIST and the best sent-folder guess."""
+
+    host, port = _require_imap_config(imap_config)
+    client = _open_imap(imap_config)
+    try:
+        typ, data = client.list()
+        if typ != "OK":
+            raise ImapAppendError(f"IMAP folder listing failed: {data!r}", temporary=True)
+
+        parsed: list[tuple[str, set[str]]] = []
+        folders: list[ImapMailboxInfo] = []
+        for item in data or []:
+            extracted = _extract_mailbox_name(item)
+            if not extracted:
+                continue
+            name, flags = extracted
+            parsed.append((name, flags))
+            folders.append(ImapMailboxInfo(name=name, flags=sorted(flags)))
+
+        return ImapFolderListResult(
+            host=host,
+            port=port,
+            security=imap_config.security.value,
+            folders=folders,
+            detected_sent_folder=_detect_sent_folder(parsed),
+        )
+    finally:
+        try:
+            client.logout()
+        except Exception:
+            pass
+
+
 def append_message_to_sent(
     message_bytes: bytes,
     *,