"""Тесты аналитики: каталог событий, буферизация и деградация без ClickHouse.

Тесты не требуют ни ClickHouse, ни aiogram: клиент подменяется фейком, а
``clickhouse_connect`` импортируется лениво внутри клиента.
"""

from __future__ import annotations

import logging
import re
from datetime import datetime
from pathlib import Path
from typing import Any

import pytest

from common.analytics import ALL_EVENT_TYPES, EventType, close_analytics, get_analytics, init_analytics, record
from common.analytics.client import PAYLOAD_MAX_LENGTH, AnalyticsClient
from common.config import Settings
from common.version import __version__

_DOCS_PATH = Path(__file__).resolve().parents[1] / "docs" / "events.md"

#: Строка каталога событий: первый столбец в обратных кавычках.
_EVENT_ROW = re.compile(r"^\|\s*`([a-z_]+)`\s*\|", re.MULTILINE)


class FakeClickHouse:
    """Заглушка клиента ClickHouse: пишет в список или падает."""

    def __init__(self, *, fail: bool = False) -> None:
        self.rows: list[list[Any]] = []
        self.table: str | None = None
        self.columns: list[str] | None = None
        self.closed = False
        self._fail = fail

    async def insert(self, table: str, data: list[list[Any]], column_names: list[str]) -> None:
        if self._fail:
            raise RuntimeError("ClickHouse недоступен")
        self.table = table
        self.columns = list(column_names)
        self.rows.extend(data)

    async def close(self) -> None:
        self.closed = True


def _settings(**overrides: Any) -> Settings:
    return Settings(_env_file=None, bot_token="1:a", **overrides)


@pytest.fixture(autouse=True)
async def _clean_singleton():
    """Тесты не должны оставлять активный singleton аналитики."""
    await close_analytics()
    yield
    await close_analytics()


def _client(**overrides: Any) -> tuple[AnalyticsClient, FakeClickHouse]:
    fake = FakeClickHouse()
    return AnalyticsClient(_settings(**overrides), client=fake), fake


# --- каталог событий ---


def test_event_types_are_unique_and_nonempty() -> None:
    assert len(ALL_EVENT_TYPES) == len(EventType)
    assert ALL_EVENT_TYPES


def test_event_types_match_documentation() -> None:
    documented = set(_EVENT_ROW.findall(_DOCS_PATH.read_text(encoding="utf-8")))
    assert documented == set(ALL_EVENT_TYPES), "Список событий в common/analytics/events.py и docs/events.md разошёлся"


# --- буферизация и запись ---


async def test_record_without_init_is_noop() -> None:
    assert get_analytics() is None
    record(EventType.MESSAGE, user_id=1, chat_id=2, payload={"a": 1})  # не должно бросать


async def test_client_buffers_and_flushes_rows() -> None:
    client, fake = _client()
    client.record(EventType.MESSAGE, user_id=11, username="vasya", chat_id=100, payload={"message_id": 5})
    client.record(EventType.COMMAND, user_id=11, username="vasya", chat_id=100, payload={"command": "/инфо"})

    assert client.pending == 2

    await client.flush()

    assert client.pending == 0
    assert fake.table == "analytics.events"
    assert fake.columns == [
        "event_time",
        "event_type",
        "user_id",
        "username",
        "chat_id",
        "payload",
        "bot_version",
        "prod",
    ]
    assert len(fake.rows) == 2

    row = fake.rows[0]
    assert isinstance(row[0], datetime)
    assert row[1] == "message"
    assert row[2] == 11
    assert row[3] == "vasya"
    assert row[4] == 100
    assert '"message_id": 5' in row[5]
    assert row[6] == __version__
    assert row[7] == 0


async def test_remember_user_enriches_username() -> None:
    client, fake = _client()
    client.remember_user(42, "nickname")
    client.record(EventType.PURIFICATION, user_id=42, chat_id=1)

    await client.flush()

    assert fake.rows[0][3] == "nickname"


async def test_record_triggers_flush_at_batch_size() -> None:
    client, _ = _client(analytics_batch_size=3)

    client.record(EventType.MESSAGE, user_id=1)
    client.record(EventType.MESSAGE, user_id=1)
    assert not client._flush_now.is_set()

    client.record(EventType.MESSAGE, user_id=1)
    assert client._flush_now.is_set()


async def test_overflow_drops_oldest_events() -> None:
    client, _ = _client(analytics_buffer_max=2, analytics_batch_size=100)

    for user_id in range(1, 5):
        client.record(EventType.MESSAGE, user_id=user_id)

    assert client.pending == 2
    assert [row[2] for row in client._rows] == [3, 4]


async def test_disabled_analytics_ignores_events() -> None:
    client, fake = _client(clickhouse_enabled=False)

    client.record(EventType.MESSAGE, user_id=1)
    await client.flush()

    assert client.pending == 0
    assert fake.rows == []


# --- деградация без ClickHouse ---


async def test_flush_failure_logs_fallback_and_drops(caplog: pytest.LogCaptureFixture) -> None:
    fake = FakeClickHouse(fail=True)
    client = AnalyticsClient(_settings(), client=fake)
    client.record(EventType.MESSAGE, user_id=1, username="vasya", chat_id=100)

    with caplog.at_level(logging.WARNING):
        await client.flush()  # не должно бросать

    assert client.pending == 0
    assert any("Fallback" in message for message in caplog.messages)


async def test_unavailable_client_falls_back_to_log(caplog: pytest.LogCaptureFixture) -> None:
    settings = _settings(clickhouse_host="127.0.0.1", clickhouse_port=1, clickhouse_password="x")
    client = AnalyticsClient(settings)
    client.record(EventType.BOT_START, payload={"app_env": "dev"})

    with caplog.at_level(logging.WARNING):
        await client.flush()

    assert client.pending == 0
    assert any("Fallback" in message for message in caplog.messages)


async def test_payload_is_truncated() -> None:
    client, fake = _client()
    client.record(EventType.MESSAGE, user_id=1, payload={"text": "x" * (PAYLOAD_MAX_LENGTH * 2)})

    await client.flush()

    assert len(fake.rows[0][5]) == PAYLOAD_MAX_LENGTH


# --- жизненный цикл ---


async def test_init_and_close_flush_pending_events() -> None:
    fake = FakeClickHouse()
    client = await init_analytics(_settings(), client=fake)

    record(EventType.BOT_START, payload={"app_env": "dev"})
    record(EventType.BOT_STOP, payload={"app_env": "dev"})

    assert get_analytics() is client
    assert client.pending == 2

    await close_analytics()

    assert get_analytics() is None
    assert len(fake.rows) == 2
    assert fake.closed is True