"""Tests for database-backed configuration store.

These tests require a real Postgres database. Set CENTRAL_TEST_DB_DSN
environment variable to override the default test database connection.
"""

import asyncio
import base64
import os
from pathlib import Path

import asyncpg
import pytest
import pytest_asyncio

from central.bootstrap_config import get_settings
from central.config_store import ConfigStore
from central.crypto import KEY_SIZE, clear_key_cache

# Test database DSN - uses central_test database with well-known test password.
# Override via CENTRAL_TEST_DB_DSN env var if your test DB differs.
TEST_DB_DSN = os.environ.get(
    "CENTRAL_TEST_DB_DSN",
    "postgresql://central_test:testpass@localhost/central_test",
)


@pytest.fixture(scope="session")
def master_key_path(tmp_path_factory: pytest.TempPathFactory) -> Path:
    """Create a master key file for the test session."""
    key = os.urandom(KEY_SIZE)
    key_path = tmp_path_factory.mktemp("keys") / "master.key"
    key_path.write_text(base64.b64encode(key).decode())
    return key_path


@pytest.fixture(autouse=True)
def setup_master_key(master_key_path: Path, monkeypatch: pytest.MonkeyPatch):
    """Configure master key path for all tests.

    CENTRAL_MASTER_KEY_PATH feeds Settings, which get_settings() lru-caches. An
    earlier test can warm that cache with the default /etc/central/master.key
    before this fixture runs, so the env change alone is not enough — clear
    get_settings (and the crypto key cache) AFTER setting the env so crypto
    rebuilds from the test key regardless of suite order, and again on teardown
    so the test key never leaks into a later test.
    """
    monkeypatch.setenv("CENTRAL_DB_DSN", TEST_DB_DSN)
    monkeypatch.setenv("CENTRAL_MASTER_KEY_PATH", str(master_key_path))
    monkeypatch.setenv("CENTRAL_CSRF_SECRET", "test-csrf-secret-for-testing-only-32chars")
    clear_key_cache()
    get_settings.cache_clear()
    yield
    clear_key_cache()
    get_settings.cache_clear()


@pytest_asyncio.fixture
async def db_conn() -> asyncpg.Connection:
    """Get a direct database connection for setup/teardown."""
    conn = await asyncpg.connect(TEST_DB_DSN)
    yield conn
    await conn.close()


@pytest_asyncio.fixture
async def clean_config_schema(db_conn: asyncpg.Connection) -> None:
    """Ensure config schema exists and is clean before each test."""
    # Create schema if not exists
    await db_conn.execute("CREATE SCHEMA IF NOT EXISTS config")

    # Create tables if not exist
    await db_conn.execute("""
        CREATE TABLE IF NOT EXISTS config.adapters (
            name           TEXT PRIMARY KEY,
            enabled        BOOLEAN NOT NULL DEFAULT true,
            cadence_s      INTEGER NOT NULL,
            settings       JSONB NOT NULL DEFAULT '{}'::jsonb,
            paused_at      TIMESTAMPTZ,
            updated_at     TIMESTAMPTZ NOT NULL DEFAULT now()
        )
    """)
    await db_conn.execute("""
        CREATE TABLE IF NOT EXISTS config.api_keys (
            alias            TEXT PRIMARY KEY,
            encrypted_value  BYTEA NOT NULL,
            created_at       TIMESTAMPTZ NOT NULL DEFAULT now(),
            rotated_at       TIMESTAMPTZ,
            last_used_at     TIMESTAMPTZ
        )
    """)

    # Create notify function with proper key detection
    await db_conn.execute("""
        CREATE OR REPLACE FUNCTION config.notify_config_change()
        RETURNS trigger AS $$
        DECLARE
            key_value TEXT;
        BEGIN
            IF TG_TABLE_NAME = 'adapters' THEN
                key_value := COALESCE(NEW.name, OLD.name, '');
            ELSIF TG_TABLE_NAME = 'api_keys' THEN
                key_value := COALESCE(NEW.alias, OLD.alias, '');
            ELSE
                key_value := '';
            END IF;

            PERFORM pg_notify('config_changed', TG_TABLE_NAME || ':' || key_value);
            RETURN COALESCE(NEW, OLD);
        END;
        $$ LANGUAGE plpgsql
    """)

    # Create triggers if not exist
    await db_conn.execute("""
        DROP TRIGGER IF EXISTS adapters_notify ON config.adapters;
        CREATE TRIGGER adapters_notify
            AFTER INSERT OR UPDATE OR DELETE ON config.adapters
            FOR EACH ROW EXECUTE FUNCTION config.notify_config_change()
    """)
    await db_conn.execute("""
        DROP TRIGGER IF EXISTS api_keys_notify ON config.api_keys;
        CREATE TRIGGER api_keys_notify
            AFTER INSERT OR UPDATE OR DELETE ON config.api_keys
            FOR EACH ROW EXECUTE FUNCTION config.notify_config_change()
    """)

    # Clean tables
    await db_conn.execute("DELETE FROM config.adapters")
    await db_conn.execute("DELETE FROM config.api_keys")


@pytest_asyncio.fixture
async def config_store(clean_config_schema: None) -> ConfigStore:
    """Create a ConfigStore connected to the test database."""
    store = await ConfigStore.create(TEST_DB_DSN)
    yield store
    await store.close()


class TestAdapterConfig:
    """Tests for adapter configuration operations."""

    @pytest.mark.asyncio
    async def test_upsert_and_get(self, config_store: ConfigStore) -> None:
        """Can insert and retrieve adapter config."""
        await config_store.upsert_adapter(
            name="test_adapter",
            enabled=True,
            cadence_s=120,
            settings={"key": "value"},
        )

        adapter = await config_store.get_adapter("test_adapter")

        assert adapter is not None
        assert adapter.name == "test_adapter"
        assert adapter.enabled is True
        assert adapter.cadence_s == 120
        assert adapter.settings == {"key": "value"}

    @pytest.mark.asyncio
    async def test_get_nonexistent(self, config_store: ConfigStore) -> None:
        """Getting nonexistent adapter returns None."""
        adapter = await config_store.get_adapter("does_not_exist")
        assert adapter is None

    @pytest.mark.asyncio
    async def test_list_adapters(self, config_store: ConfigStore) -> None:
        """Can list all adapters."""
        await config_store.upsert_adapter("adapter_a", True, 60, {})
        await config_store.upsert_adapter("adapter_b", False, 300, {"x": 1})

        adapters = await config_store.list_adapters()

        assert len(adapters) == 2
        names = [a.name for a in adapters]
        assert "adapter_a" in names
        assert "adapter_b" in names

    @pytest.mark.asyncio
    async def test_upsert_updates_existing(self, config_store: ConfigStore) -> None:
        """Upsert updates existing adapter."""
        await config_store.upsert_adapter("updater", True, 60, {"v": 1})
        await config_store.upsert_adapter("updater", False, 120, {"v": 2})

        adapter = await config_store.get_adapter("updater")

        assert adapter is not None
        assert adapter.enabled is False
        assert adapter.cadence_s == 120
        assert adapter.settings == {"v": 2}

    @pytest.mark.asyncio
    async def test_pause_unpause(self, config_store: ConfigStore) -> None:
        """Can pause and unpause adapter."""
        await config_store.upsert_adapter("pausable", True, 60, {})

        await config_store.pause_adapter("pausable")
        adapter = await config_store.get_adapter("pausable")
        assert adapter is not None
        assert adapter.is_paused is True

        await config_store.unpause_adapter("pausable")
        adapter = await config_store.get_adapter("pausable")
        assert adapter is not None
        assert adapter.is_paused is False


class TestApiKeys:
    """Tests for API key operations."""

    @pytest.mark.asyncio
    async def test_set_and_get_key(self, config_store: ConfigStore) -> None:
        """Can store and retrieve encrypted API key."""
        await config_store.set_api_key("test_key", "super_secret_value")

        value = await config_store.get_api_key("test_key")

        assert value == "super_secret_value"

    @pytest.mark.asyncio
    async def test_get_nonexistent_key(self, config_store: ConfigStore) -> None:
        """Getting nonexistent key returns None."""
        value = await config_store.get_api_key("does_not_exist")
        assert value is None

    @pytest.mark.asyncio
    async def test_key_rotation(self, config_store: ConfigStore) -> None:
        """Updating key sets rotated_at."""
        await config_store.set_api_key("rotate_me", "value1")
        await config_store.set_api_key("rotate_me", "value2")

        value = await config_store.get_api_key("rotate_me")
        assert value == "value2"

    @pytest.mark.asyncio
    async def test_delete_key(self, config_store: ConfigStore) -> None:
        """Can delete API key."""
        await config_store.set_api_key("delete_me", "value")

        deleted = await config_store.delete_api_key("delete_me")
        assert deleted is True

        value = await config_store.get_api_key("delete_me")
        assert value is None

    @pytest.mark.asyncio
    async def test_delete_nonexistent(self, config_store: ConfigStore) -> None:
        """Deleting nonexistent key returns False."""
        deleted = await config_store.delete_api_key("never_existed")
        assert deleted is False


class TestNotifications:
    """Tests for LISTEN/NOTIFY functionality."""

    @pytest.mark.asyncio
    async def test_notify_on_adapter_change(self, config_store: ConfigStore) -> None:
        """NOTIFY fires when adapter is changed."""
        notifications: list[tuple[str, str]] = []
        notification_received = asyncio.Event()

        async def callback(table: str, key: str) -> None:
            notifications.append((table, key))
            notification_received.set()

        # Start listener in background
        listen_task = asyncio.create_task(config_store.listen_for_changes(callback))

        try:
            # Give listener time to subscribe
            await asyncio.sleep(0.1)

            # Trigger a change
            await config_store.upsert_adapter("notify_test", True, 60, {})

            # Wait for notification (with timeout)
            try:
                await asyncio.wait_for(notification_received.wait(), timeout=5.0)
            except asyncio.TimeoutError:
                pytest.fail("Notification not received within timeout")

            assert len(notifications) >= 1
            assert notifications[0][0] == "adapters"
            assert notifications[0][1] == "notify_test"

        finally:
            listen_task.cancel()
            try:
                await listen_task
            except asyncio.CancelledError:
                pass

    @pytest.mark.asyncio
    async def test_notify_on_api_key_change(self, config_store: ConfigStore) -> None:
        """NOTIFY fires when API key is changed."""
        notifications: list[tuple[str, str]] = []
        notification_received = asyncio.Event()

        async def callback(table: str, key: str) -> None:
            notifications.append((table, key))
            notification_received.set()

        listen_task = asyncio.create_task(config_store.listen_for_changes(callback))

        try:
            await asyncio.sleep(0.1)
            await config_store.set_api_key("notify_key", "secret")

            try:
                await asyncio.wait_for(notification_received.wait(), timeout=5.0)
            except asyncio.TimeoutError:
                pytest.fail("Notification not received within timeout")

            assert len(notifications) >= 1
            assert notifications[0][0] == "api_keys"
            assert notifications[0][1] == "notify_key"

        finally:
            listen_task.cancel()
            try:
                await listen_task
            except asyncio.CancelledError:
                pass


class TestListenerReconnect:
    """Tests for listener reconnection on connection loss."""

    @pytest.mark.asyncio
    async def test_listener_cancellation_propagates(
        self, config_store: ConfigStore
    ) -> None:
        """Cancellation cleanly stops the listener without reconnect loop."""
        async def callback(table: str, key: str) -> None:
            pass

        listen_task = asyncio.create_task(config_store.listen_for_changes(callback))

        # Give listener time to start
        await asyncio.sleep(0.1)

        # Cancel and verify it stops
        listen_task.cancel()
        try:
            await asyncio.wait_for(listen_task, timeout=2.0)
        except asyncio.CancelledError:
            pass  # Expected
        except asyncio.TimeoutError:
            pytest.fail("Listener did not stop after cancellation")

        assert listen_task.cancelled() or listen_task.done()


def test_master_key_path_is_isolated(master_key_path: Path) -> None:
    """Contract: after setup_master_key runs, get_settings() resolves the master
    key to the per-session test key — never the production /etc/central path —
    regardless of suite order. Fails on the pre-fix code in a full-suite run
    where get_settings was warmed with the default path by an earlier test.
    """
    assert get_settings().master_key_path == master_key_path
    assert get_settings().master_key_path != Path("/etc/central/master.key")