"""Reset a corrupt last_consolidated offset instead of hiding history (#4066)."""

import json
from pathlib import Path

from nanobot.session.manager import Session, SessionManager


def _session(count: int, last_consolidated: object) -> Session:
    msgs = [{"role": "user", "content": f"msg{i}"} for i in range(count)]
    return Session(key="chan:chat", messages=msgs, last_consolidated=last_consolidated)


def test_out_of_range_offset_is_reset():
    assert _session(10, 999).last_consolidated == 0
    assert _session(3, -5).last_consolidated == 0


def test_non_integer_offset_is_reset():
    for offset in ("999", None, 0.5, True):
        assert _session(3, offset).last_consolidated == 0


def test_loaded_corrupt_offset_keeps_messages(tmp_path: Path):
    offsets = {
        "string": "999",
        "null": None,
        "float": 0.5,
        "bool": True,
    }

    for name, offset in offsets.items():
        manager = SessionManager(tmp_path / name)
        path = manager._get_session_path("chan:chat")
        path.parent.mkdir(parents=True, exist_ok=True)
        message = {"role": "user", "content": f"survived {name}"}
        path.write_text(
            "\n".join([
                json.dumps({
                    "_type": "metadata",
                    "key": "chan:chat",
                    "metadata": {},
                    "last_consolidated": offset,
                }),
                json.dumps(message),
            ]) + "\n",
            encoding="utf-8",
        )

        session = manager.get_or_create("chan:chat")

        assert session.messages == [message]
        assert session.last_consolidated == 0
        assert session.get_history(max_messages=10) == [message]


def test_valid_offset_is_preserved():
    session = _session(10, 4)
    assert session.last_consolidated == 4
    assert len(session.get_history()) == 6