feat(mail): map standard IMAP folders per profile

src/govoplan_mail/backend/sending/imap.py

@@ -103,6 +103,7 @@ class ImapFolderListResult:
     security: str
     folders: list[ImapMailboxInfo]
     detected_sent_folder: str | None = None
+    detected_folder_mappings: dict[str, str] | None = None
 
 
 @dataclass(frozen=True, slots=True)
@@ -317,25 +318,47 @@ def _extract_mailbox_name(list_response_line: bytes | str) -> tuple[str, set[str
     return None
 
 
-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
+_STANDARD_FOLDER_FLAGS: dict[str, tuple[str, ...]] = {
+    "inbox": ("\\inbox",),
+    "sent": ("\\sent", "\\sentmail"),
+    "drafts": ("\\drafts",),
+    "trash": ("\\trash",),
+    "archive": ("\\archive", "\\all"),
+    "junk": ("\\junk", "\\spam"),
+}
 
-    common_names = [
-        "Sent",
-        "Sent Items",
-        "Sent Messages",
-        "Gesendet",
-        "Gesendete Elemente",
-        "INBOX.Sent",
-        "INBOX/Sent",
-    ]
-    names = {name.lower(): name for name, _ in parsed}
-    for candidate in common_names:
-        if candidate.lower() in names:
-            return names[candidate.lower()]
-    return None
+_STANDARD_FOLDER_NAMES: dict[str, tuple[str, ...]] = {
+    "inbox": ("INBOX", "Posteingang"),
+    "sent": ("Sent", "Sent Items", "Sent Messages", "Gesendet", "Gesendete Elemente", "INBOX.Sent", "INBOX/Sent"),
+    "drafts": ("Drafts", "Entwürfe", "Entwuerfe"),
+    "trash": ("Trash", "Deleted Items", "Gelöscht", "Geloescht", "Papierkorb"),
+    "archive": ("Archive", "Archives", "Archiv"),
+    "junk": ("Junk", "Spam", "Junk Email", "Unerwünscht", "Unerwuenscht"),
+}
+
+
+def _detect_standard_folder_mappings(parsed: list[tuple[str, set[str]]]) -> dict[str, str]:
+    detected: dict[str, str] = {}
+    for role, accepted_flags in _STANDARD_FOLDER_FLAGS.items():
+        for name, flags in parsed:
+            if any(flag in flags for flag in accepted_flags):
+                detected[role] = name
+                break
+
+    names = {name.casefold(): name for name, _ in parsed}
+    for role, candidates in _STANDARD_FOLDER_NAMES.items():
+        if role in detected:
+            continue
+        for candidate in candidates:
+            match = names.get(candidate.casefold())
+            if match:
+                detected[role] = match
+                break
+    return detected
+
+
+def _detect_sent_folder(parsed: list[tuple[str, set[str]]]) -> str | None:
+    return _detect_standard_folder_mappings(parsed).get("sent")
 
 
 def discover_sent_folder(client: imaplib.IMAP4) -> str | None:
@@ -402,12 +425,18 @@ def _mock_imap_folders(*, imap_config: ImapConfig) -> ImapFolderListResult:
         name = str(item["name"])
         count = sum(1 for record in records if _mock_folder_matches(record, name))
         folders.append(ImapMailboxInfo(name=name, flags=list(item.get("flags") or []), message_count=count, unseen_count=None))
+    parsed = [
+        (str(item["name"]), {str(flag).lower() for flag in item.get("flags") or []})
+        for item in MOCK_IMAP_FOLDERS
+    ]
+    detected = _detect_standard_folder_mappings(parsed)
     return ImapFolderListResult(
         host=host,
         port=port,
         security=imap_config.security.value,
         folders=folders,
-        detected_sent_folder="Sent",
+        detected_sent_folder=detected.get("sent"),
+        detected_folder_mappings=detected,
     )
 
 
@@ -438,12 +467,14 @@ def _list_imap_folders_on_client(
         )
         folders.append(ImapMailboxInfo(name=name, flags=sorted(flags), message_count=message_count, unseen_count=unseen_count))
 
+    detected = _detect_standard_folder_mappings(parsed)
     return ImapFolderListResult(
         host=host,
         port=port,
         security=security,
         folders=folders,
-        detected_sent_folder=_detect_sent_folder(parsed),
+        detected_sent_folder=detected.get("sent"),
+        detected_folder_mappings=detected,
     )