"""Integration tests for src/my_deepagent/persistence/checkpointer.py.

v0.2 PR #1: rewritten for AsyncPostgresSaver (LangGraph Postgres checkpointer).
The legacy SqliteSaver / Path-based API is removed.

Requires the docker-compose `devflow-postgres` container; the ``pg_db_url``
fixture from ``tests/conftest.py`` creates a fresh DB per test.
"""

from __future__ import annotations

import pytest

from my_deepagent.persistence.checkpointer import _to_psycopg_dsn, get_checkpointer_ctx


class TestToPsycopgDsn:
    """Pure-function tests for the SQLAlchemy → libpq DSN converter."""

    def test_strips_asyncpg_prefix(self) -> None:
        url = "postgresql+asyncpg://u:p@h:1/d"
        assert _to_psycopg_dsn(url) == "postgresql://u:p@h:1/d"

    def test_strips_psycopg_prefix(self) -> None:
        url = "postgresql+psycopg://u:p@h:1/d"
        assert _to_psycopg_dsn(url) == "postgresql://u:p@h:1/d"

    def test_bare_postgres_url_passes_through(self) -> None:
        url = "postgresql://u:p@h:1/d"
        assert _to_psycopg_dsn(url) == url

    def test_non_postgres_url_passes_through(self) -> None:
        url = "sqlite:///x"
        assert _to_psycopg_dsn(url) == url


@pytest.mark.integration
class TestGetCheckpointerCtx:
    """Tests for the async get_checkpointer_ctx context manager."""

    @pytest.mark.asyncio
    async def test_ctx_yields_saver(self, pg_db_url: str) -> None:
        """Entering the async context yields a non-None saver."""
        async with get_checkpointer_ctx(pg_db_url) as saver:
            assert saver is not None

    @pytest.mark.asyncio
    async def test_setup_is_idempotent(self, pg_db_url: str) -> None:
        """``saver.setup()`` is invoked on entry; entering twice must not error."""
        async with get_checkpointer_ctx(pg_db_url) as first:
            assert first is not None
        # A second open against the same DB must not raise — setup() is idempotent.
        async with get_checkpointer_ctx(pg_db_url) as second:
            assert second is not None

    @pytest.mark.asyncio
    async def test_accepts_sqlalchemy_url(self, pg_db_url: str) -> None:
        """SQLAlchemy-style ``postgresql+asyncpg://`` URLs are accepted."""
        assert pg_db_url.startswith("postgresql+asyncpg://")
        async with get_checkpointer_ctx(pg_db_url) as saver:
            assert saver is not None