for last 7 days of messages remove large messages first, then by age

chatmaild/src/chatmaild/expire.py

@@ -99,11 +99,29 @@ def scan_mailbox_messages(mbox):
     return messages
 
 
+# Within this window, large messages are deleted before small ones.
+DELETE_LARGE_FIRST_DAYS = 7
+
+
 def expire_to_target(mbox, target_bytes):
+    cutoff = time.time() - DELETE_LARGE_FIRST_DAYS * 86400
     messages = scan_mailbox_messages(mbox)
+
+    def sort_key(msg):
+        # prio 0: Older than cutoff -> remove oldest first
+        if msg.mtime < cutoff:
+            return (0, msg.mtime)
+
+        # prio 1: more recent than cutoff, large -> remove largest first
+        if msg.quota_size > 200000:
+            return (1, -msg.quota_size, msg.mtime)
+
+        # prio 2: more recent than cutoff, small -> remove oldest first
+        return (2, msg.mtime)
+
     total_size = sum(m.quota_size for m in messages)
     removed = 0
-    for entry in sorted(messages):
+    for entry in sorted(messages, key=sort_key):
         if total_size <= target_bytes:
             break
         (mbox / entry.path).unlink(missing_ok=True)

chatmaild/src/chatmaild/tests/test_expire.py

@@ -1,6 +1,7 @@
 import itertools
 import os
 import random
+import shutil
 import time
 from datetime import datetime
 from fnmatch import fnmatch
@@ -240,6 +241,33 @@ def test_expire_to_target(tmp_path):
     assert len(scan_mailbox_messages(tmp_path)) == 1
 
 
+def test_expire_to_target_prioritization(tmp_path):
+    def create_messages():
+        for sub in ("cur", "new"):
+            if (tmp_path / sub).exists():
+                shutil.rmtree(tmp_path / sub)
+        # prio 0: older than 7 days
+        _create_message(tmp_path, "cur", 5 * MB, days_old=10)
+        # prio 1: last 7 days, large (>200KB)
+        _create_message(tmp_path, "cur", 5 * MB, days_old=1)
+        # prio 2: last 7 days, small
+        _create_message(tmp_path, "cur", 1000, days_old=2)
+
+    # Shrink to 6MB: only the old message (prio 0) is removed.
+    create_messages()
+    assert expire_to_target(tmp_path, 6 * MB) == 1
+    msgs = scan_mailbox_messages(tmp_path)
+    assert len(msgs) == 2
+    assert all(m.mtime > time.time() - 7 * 86400 for m in msgs)
+
+    # Shrink to 1KB: old and recent-large removed, small survives.
+    create_messages()
+    assert expire_to_target(tmp_path, 1024) == 2
+    msgs = scan_mailbox_messages(tmp_path)
+    assert len(msgs) == 1
+    assert msgs[0].quota_size == 1000
+
+
 def test_quota_expire_main(tmp_path, capsys):
     mbox = tmp_path / "user@example.org"
     _create_message(mbox, "cur", 2 * MB, days_old=5)