"""Shared test fixtures with in-memory SQLite database.

Session-based auth: tests create users and sessions directly in the DB,
matching the Better-Auth session validation flow.
"""

import secrets
import uuid
from datetime import UTC, datetime, timedelta

import pytest
from httpx import ASGITransport, AsyncClient
from sqlalchemy import String, TypeDecorator, Uuid, create_engine, event, text
from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
from sqlalchemy.orm import sessionmaker
from sqlalchemy.types import CHAR

from cartsnitch_api.config import settings as cartsnitch_settings
from cartsnitch_api.database import get_db
from cartsnitch_api.main import create_app
from cartsnitch_api.middleware import rate_limit as _rate_limit_module
from cartsnitch_api.models import Base


class _StringUUID(TypeDecorator):
    """TypeDecorator that lets Text/String/UUID columns accept uuid.UUID on bind.

    SQLite has no native UUID type — passing a ``uuid.UUID`` raises
    ``type 'UUID' is not supported``. This stores UUID values as their hex
    string in the DB, accepts either uuid.UUID or str at bind time, and
    returns uuid.UUID on read so existing test assertions like
    ``isinstance(store.id, uuid.UUID)`` still work.
    """

    impl = CHAR(36)
    cache_ok = True

    def process_bind_param(self, value, dialect):
        if value is None:
            return None
        if isinstance(value, uuid.UUID):
            return str(value)
        return str(value)

    def process_result_value(self, value, dialect):
        if value is None:
            return None
        if isinstance(value, uuid.UUID):
            return value
        return uuid.UUID(value)


def _set_timestamp_defaults(mapper, connection, target):
    """Populate created_at/updated_at and missing PK IDs for SQLite.

    SQLite can't bind ``uuid.UUID`` objects to Text/String columns, and has
    no server-side default for ``func.now()`` or ``gen_random_uuid()``. We
    strip those server_defaults elsewhere; this listener fills in
    Python-side timestamp defaults at insert time, generates IDs for PK
    columns that have no default, and populates ``func.now()`` columns
    whose server_default was stripped (e.g. ``ingested_at``). UUID values
    for non-PK columns are converted by the ``_StringUUID`` TypeDecorator.
    """
    now = datetime.now(UTC)
    for col in mapper.columns:
        key = col.key
        if key in ("created_at", "updated_at"):
            if getattr(target, key, None) is None:
                setattr(target, key, now)
            continue
        if col.primary_key and getattr(target, key, None) is None:
            setattr(target, key, str(uuid.uuid4()))
            continue
        if getattr(col, "_sqlite_default_now", False) and getattr(target, key, None) is None:
            setattr(target, key, now)


def _adapt_columns_for_sqlite():
    """Strip Postgres-only server_defaults and adapt UUID columns for SQLite.

    Must be called BEFORE ``Base.metadata.create_all`` so the DDL reflects
    the adapted column types.
    """
    for tbl in Base.metadata.tables.values():
        for col in tbl.columns.values():
            # Strip PostgreSQL-specific function server_defaults (gen_random_uuid,
            # gen_random_bytes, now()) but keep simple string-literal defaults
            # like ``server_default="false"`` since they work in SQLite.
            sd = col.server_default
            if sd is not None:
                sd_text = str(sd.arg) if hasattr(sd, "arg") else str(sd)
                sd_text = sd_text.lower()
                if any(x in sd_text for x in ["gen_random_uuid", "gen_random_bytes", "now()"]):
                    col.server_default = None
                    if "now()" in sd_text and not col.nullable:
                        col._sqlite_default_now = True  # type: ignore[attr-defined]

            # Replace UUID column types with a SQLite-compatible TypeDecorator
            if isinstance(col.type, Uuid):
                col.type = _StringUUID()

            # Text/String PK columns without a default need the _StringUUID type
            # so the before_insert listener can generate hex-string IDs.
            if col.primary_key and col.default is None and col.server_default is None:
                if not isinstance(col.type, _StringUUID):
                    col.type = _StringUUID()

            # FK columns that may receive uuid.UUID values from test code
            if col.foreign_keys and not col.primary_key and isinstance(col.type, String):
                col.type = _StringUUID()


def _register_event_listeners():
    """Attach before_insert listener to every mapped class."""
    for cls in Base.registry._class_registry.values():
        if hasattr(cls, "__mapper__"):
            event.listen(cls, "before_insert", _set_timestamp_defaults)


TEST_JWT_SECRET = secrets.token_urlsafe(32)
TEST_SERVICE_KEY = secrets.token_urlsafe(32)
TEST_FERNET_KEY = "7reF42nmTwbdN21PBoubGp7h_FU8qSimstmlaMLoRK8="


@pytest.fixture(autouse=True)
def setup_test_settings():
    original_jwt = cartsnitch_settings.jwt_secret_key
    original_service = cartsnitch_settings.service_key
    original_fernet = cartsnitch_settings.fernet_key
    cartsnitch_settings.jwt_secret_key = TEST_JWT_SECRET
    cartsnitch_settings.service_key = TEST_SERVICE_KEY
    cartsnitch_settings.fernet_key = TEST_FERNET_KEY
    yield
    cartsnitch_settings.jwt_secret_key = original_jwt
    cartsnitch_settings.service_key = original_service
    cartsnitch_settings.fernet_key = original_fernet


TEST_DATABASE_URL = "sqlite+aiosqlite:///:memory:"


@pytest.fixture(autouse=True)
def disable_rate_limiting():
    """Disable rate limiting for all tests to prevent 429 interference.

    The rate_limit module creates its Redis client at import time when
    ``settings.rate_limit_redis_enabled`` is true. We can't undo that by
    flipping the setting inside the fixture — the client and the
    Redis-backed limiters are already constructed. So we swap them out
    for the in-memory limiters directly on the module, which also
    prevents "Event loop is closed" errors when the redis client tries
    to disconnect after the test event loop ends.
    """
    cartsnitch_settings.rate_limit_enabled = False
    cartsnitch_settings.rate_limit_redis_enabled = False
    original_public = _rate_limit_module._public_limiter
    original_auth = _rate_limit_module._auth_limiter
    original_auth_strict = _rate_limit_module._auth_strict_limiter
    _rate_limit_module._redis_client = None
    _rate_limit_module._use_redis = False
    _rate_limit_module._public_limiter = _rate_limit_module.InMemorySlidingWindow(
        cartsnitch_settings.rate_limit_requests, cartsnitch_settings.rate_limit_window_seconds
    )
    _rate_limit_module._auth_limiter = _rate_limit_module.InMemorySlidingWindow(
        cartsnitch_settings.rate_limit_requests * 5, cartsnitch_settings.rate_limit_window_seconds
    )
    _rate_limit_module._auth_strict_limiter = _rate_limit_module.InMemorySlidingWindow(
        cartsnitch_settings.rate_limit_auth_requests,
        cartsnitch_settings.rate_limit_auth_window_seconds,
    )
    yield
    cartsnitch_settings.rate_limit_enabled = True
    cartsnitch_settings.rate_limit_redis_enabled = True
    _rate_limit_module._public_limiter = original_public
    _rate_limit_module._auth_limiter = original_auth
    _rate_limit_module._auth_strict_limiter = original_auth_strict


@pytest.fixture
def engine():
    """Sync in-memory SQLite engine for model unit tests.

    Strips PostgreSQL-specific server_default expressions, replaces UUID
    column types with a SQLite-compatible TypeDecorator, and registers a
    before_insert event listener to populate timestamps.
    """
    eng = create_engine("sqlite:///:memory:")
    _adapt_columns_for_sqlite()
    _register_event_listeners()
    Base.metadata.create_all(eng)
    yield eng
    eng.dispose()


@pytest.fixture
def session(engine):
    """Sync SQLAlchemy session for model unit tests."""
    factory = sessionmaker(bind=engine)
    with factory() as sess:
        yield sess


@pytest.fixture
async def db_engine():
    engine = create_async_engine(TEST_DATABASE_URL, echo=False)

    @event.listens_for(engine.sync_engine, "connect")
    def set_sqlite_pragma(dbapi_connection, connection_record):
        cursor = dbapi_connection.cursor()
        cursor.execute("PRAGMA foreign_keys=ON")
        cursor.close()

    _adapt_columns_for_sqlite()
    _register_event_listeners()

    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)
        await conn.execute(
            text("""
            CREATE TABLE IF NOT EXISTS sessions (
                id TEXT PRIMARY KEY,
                token TEXT NOT NULL UNIQUE,
                user_id TEXT NOT NULL,
                expires_at TIMESTAMP NOT NULL,
                ip_address TEXT,
                user_agent TEXT,
                created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL,
                updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL
            )
        """)
        )
        await conn.execute(
            text("""
            CREATE TABLE IF NOT EXISTS accounts (
                id TEXT PRIMARY KEY,
                user_id TEXT NOT NULL,
                account_id TEXT NOT NULL,
                provider_id TEXT NOT NULL,
                access_token TEXT,
                refresh_token TEXT,
                access_token_expires_at TIMESTAMP,
                refresh_token_expires_at TIMESTAMP,
                scope TEXT,
                id_token TEXT,
                password TEXT,
                created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL,
                updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL
            )
        """)
        )
        await conn.execute(
            text("""
            CREATE TABLE IF NOT EXISTS verifications (
                id TEXT PRIMARY KEY,
                identifier TEXT NOT NULL,
                value TEXT NOT NULL,
                expires_at TIMESTAMP NOT NULL,
                created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL,
                updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL
            )
        """)
        )

    yield engine

    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.drop_all)

    await engine.dispose()


@pytest.fixture
async def db_session(db_engine):
    factory = async_sessionmaker(db_engine, class_=AsyncSession, expire_on_commit=False)
    async with factory() as session:
        yield session


@pytest.fixture
async def client(db_engine):
    factory = async_sessionmaker(db_engine, class_=AsyncSession, expire_on_commit=False)

    async def override_get_db():
        async with factory() as session:
            yield session

    app = create_app()
    app.dependency_overrides[get_db] = override_get_db

    transport = ASGITransport(app=app)
    async with AsyncClient(transport=transport, base_url="http://test") as ac:
        yield ac

    app.dependency_overrides.clear()


async def _create_test_user_and_session(
    client: AsyncClient, db_engine, **user_overrides
) -> tuple[dict, str]:
    """Create a test user and a valid session directly in the DB.

    Returns (user_dict, session_token).  Better-Auth stores the raw token
    in the DB, so we insert it as-is.
    """
    user_id = str(uuid.uuid4())
    email = user_overrides.get("email", "test@example.com")
    display_name = user_overrides.get("display_name", "Test User")
    session_token = secrets.token_urlsafe(32)
    session_id = str(uuid.uuid4())
    now = datetime.now(UTC).isoformat()
    expires = (datetime.now(UTC) + timedelta(days=7)).isoformat()

    async with db_engine.begin() as conn:
        await conn.execute(
            text(
                "INSERT INTO users (id, email, hashed_password, display_name, "
                "email_verified, email_inbound_token, created_at, updated_at) "
                "VALUES (:id, :email, :hashed_password, :display_name, "
                ":email_verified, :email_inbound_token, :created_at, :updated_at)"
            ),
            {
                "id": user_id,
                "email": email,
                "hashed_password": "not-used-with-better-auth",
                "display_name": display_name,
                "email_verified": False,
                "email_inbound_token": secrets.token_urlsafe(16),
                "created_at": now,
                "updated_at": now,
            },
        )
        await conn.execute(
            text(
                "INSERT INTO sessions (id, token, user_id, expires_at, created_at, updated_at) "
                "VALUES (:id, :token, :user_id, :expires_at, :created_at, :updated_at)"
            ),
            {
                "id": session_id,
                "token": session_token,
                "user_id": user_id,
                "expires_at": expires,
                "created_at": now,
                "updated_at": now,
            },
        )

    return {"id": user_id, "email": email, "display_name": display_name}, session_token


@pytest.fixture
async def auth_headers(client, db_engine):
    """Create a test user with a valid session and return auth headers."""
    _, session_token = await _create_test_user_and_session(client, db_engine)
    return {"Cookie": f"better-auth.session_token={session_token}"}