from __future__ import annotations

import json
from pathlib import Path

import pytest

from conversation_manager import ConversationManager


def test_conversation_manager_persists_history(tmp_path: Path) -> None:
    manager = ConversationManager(storage_dir=tmp_path, conversation_id="test")
    manager.append_message("user", "Hello there!")
    manager.append_message("assistant", "General Kenobi.")

    conversation_file = tmp_path / "test.json"
    assert conversation_file.exists()

    data = json.loads(conversation_file.read_text(encoding="utf-8"))
    assert len(data["messages"]) == 2
    assert data["messages"][0]["content"] == "Hello there!"

    reloaded = ConversationManager(storage_dir=tmp_path, conversation_id="test")
    assert [msg["content"] for msg in reloaded.messages] == [
        "Hello there!",
        "General Kenobi.",
    ]


def test_conversation_manager_rejects_invalid_role(tmp_path: Path) -> None:
    manager = ConversationManager(storage_dir=tmp_path, conversation_id="invalid")

    with pytest.raises(ValueError):
        manager.append_message("narrator", "This should fail.")