from __future__ import annotations

import unittest

from govoplan_mail.backend.sending.imap import (
    _detect_sent_folder,
    _extract_mailbox_name,
    _paged_descending_sequences,
    _parse_fetch_sequence,
    _sequence_set,
)


class ImapFolderParserTests(unittest.TestCase):
    def test_extracts_quoted_mailbox_after_quoted_delimiter(self):
        self.assertEqual(
            _extract_mailbox_name(b'(\\HasNoChildren \\Sent) "/" "Sent Items"'),
            ("Sent Items", {"\\hasnochildren", "\\sent"}),
        )

    def test_extracts_atom_mailbox(self):
        self.assertEqual(
            _extract_mailbox_name('(\\HasNoChildren) "/" INBOX'),
            ("INBOX", {"\\hasnochildren"}),
        )

    def test_extracts_nil_delimiter_mailbox(self):
        self.assertEqual(
            _extract_mailbox_name('(\\HasNoChildren) NIL "INBOX.Sent"'),
            ("INBOX.Sent", {"\\hasnochildren"}),
        )

    def test_detects_sent_by_flag_before_name(self):
        self.assertEqual(
            _detect_sent_folder([("Archive", {"\\sent"}), ("Sent", set())]),
            "Archive",
        )

    def test_detects_common_sent_name(self):
        self.assertEqual(
            _detect_sent_folder([("INBOX", set()), ("Gesendet", set())]),
            "Gesendet",
        )


class ImapMessagePaginationTests(unittest.TestCase):
    def test_paginates_sequence_numbers_newest_first(self):
        self.assertEqual(
            _paged_descending_sequences(120, offset=0, limit=5),
            ["120", "119", "118", "117", "116"],
        )
        self.assertEqual(_paged_descending_sequences(120, offset=118, limit=5), ["2", "1"])
        self.assertEqual(_paged_descending_sequences(120, offset=120, limit=5), [])

    def test_compacts_contiguous_sequence_sets(self):
        self.assertEqual(_sequence_set(["5", "4", "3"]), "3:5")
        self.assertEqual(_sequence_set(["9", "7", "5"]), "5,7,9")

    def test_extracts_fetch_sequence_number(self):
        self.assertEqual(
            _parse_fetch_sequence("42 (UID 123 FLAGS (\\Seen) RFC822.SIZE 100)"),
            "42",
        )
        self.assertIsNone(_parse_fetch_sequence("UID 123 FLAGS ()"))


if __name__ == "__main__":
    unittest.main()