"""Unit tests for `app.services.dadata.clean_address`.

Coverage:
- happy path: mocked httpx 200 → parsed DadataAddressResult
- no API key → None gracefully (no httpx call)
- network failure (TimeoutException) → None + warning log
- network failure (NetworkError) → None
- HTTP 429 quota exceeded → None
- HTTP 401 / 403 auth rejected → None
- HTTP 5xx → None
- empty response array → None
- non-list response → None
- response item missing canonical address → None
- short address (< 3 chars) → None
- credentials present but secret blank → None

NEVER calls real DaData API — все запросы mock'аются через httpx.MockTransport
(consistent с tests/test_backfill_house_coords.py + test_audit_address_mismatch.py).
"""

from __future__ import annotations

import os
import sys
from unittest.mock import MagicMock, patch

import httpx
import pytest

# DATABASE_URL required by config before any app import (см. test_cadastral_reverse.py).
os.environ.setdefault("DATABASE_URL", "postgresql+psycopg://test:test@localhost:5432/test")

# WeasyPrint stub — not installed in CI без GTK
_wp_mock = MagicMock()
sys.modules.setdefault("weasyprint", _wp_mock)


# Sample response mimics real DaData payload для «Екатеринбург, ул. Малышева, 125»
# (см. PR Q1 task description в gendesign vault meta/00_credentials.md).
SAMPLE_OK_PAYLOAD = [
    {
        "source": "Екатеринбург, улица Малышева, 125",
        "result": "г Екатеринбург, ул Малышева, д 125",
        "house_cadnum": "66:41:0704045:350",
        "house_fias_id": "74457c2f-1234-5678-90ab-cdef01234567",
        "geo_lat": "56.840851",
        "geo_lon": "60.654071",
        "qc_geo": 0,
        "qc_house": 2,
        "kladr_id": "6600000100006480117",
        "okato": "65401000000",
        "oktmo": "65701000001",
        "metro": [
            {"name": "Площадь 1905 года", "line": "Первая", "distance": 3.4},
            {"name": "Геологическая", "line": "Первая", "distance": 4.1},
        ],
    }
]


def _mock_transport_returning(
    status_code: int = 200, payload: object = SAMPLE_OK_PAYLOAD
) -> httpx.MockTransport:
    """httpx MockTransport — returns desired status + JSON payload for every request."""

    def handler(request: httpx.Request) -> httpx.Response:
        # Sanity: запрос должен идти на DaData /clean/address с правильными headers
        assert "cleaner.dadata.ru" in str(request.url)
        assert request.headers.get("Authorization", "").startswith("Token ")
        assert request.headers.get("X-Secret")
        return httpx.Response(status_code, json=payload)

    return httpx.MockTransport(handler)


# Snapshot real httpx.AsyncClient ДО любых patch'ей — фабрика ниже использует
# именно его, чтобы patch'нутый `httpx.AsyncClient` не вызывал recursion
# (см. PR Q1 — fix recursion в test mocks).
_REAL_ASYNC_CLIENT = httpx.AsyncClient


def _async_client_factory(transport: httpx.MockTransport):
    """Returns drop-in replacement for httpx.AsyncClient that uses our MockTransport.

    Принимает любые kwargs конструктора (timeout=…) и игнорирует их —
    использует _REAL_ASYNC_CLIENT с подменённым transport.
    """

    def factory(*_: object, **__: object) -> httpx.AsyncClient:
        return _REAL_ASYNC_CLIENT(transport=transport)

    return factory


def _patch_settings(token: str | None = "fake-token", secret: str | None = "fake-secret"):
    """Patch app.services.dadata.settings with given credentials."""
    fake = MagicMock()
    fake.dadata_api_token = token
    fake.dadata_api_secret = secret
    return patch("app.services.dadata.settings", fake)


def _patch_async_client(transport: httpx.MockTransport):
    """Patch the httpx.AsyncClient used inside dadata module."""
    return patch("app.services.dadata.httpx.AsyncClient", _async_client_factory(transport))


# ── happy path ────────────────────────────────────────────────────────────────


async def test_clean_address_happy_path_returns_parsed_result() -> None:
    """Mocked 200 → DadataAddressResult с canonical/cadnum/lat/lon/metro."""
    from app.services import dadata

    transport = _mock_transport_returning(200, SAMPLE_OK_PAYLOAD)
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Екатеринбург, ул. Малышева, 125")

    assert result is not None
    assert result.canonical_address == "г Екатеринбург, ул Малышева, д 125"
    assert result.house_cadnum == "66:41:0704045:350"
    assert result.house_fias_id == "74457c2f-1234-5678-90ab-cdef01234567"
    assert result.lat is not None
    assert abs(result.lat - 56.840851) < 1e-6
    assert result.lon is not None
    assert abs(result.lon - 60.654071) < 1e-6
    assert result.qc_geo == 0
    assert result.qc_house == 2
    assert result.kladr_id == "6600000100006480117"
    assert result.okato == "65401000000"
    assert result.oktmo == "65701000001"
    assert len(result.metro) == 2
    assert result.metro[0]["name"] == "Площадь 1905 года"
    # raw payload preserved для debugging
    assert result.raw["house_cadnum"] == "66:41:0704045:350"


# ── credentials missing → graceful None ─────────────────────────────────────


async def test_clean_address_returns_none_when_token_missing() -> None:
    """DADATA_API_TOKEN не задан → None, никакого httpx-вызова."""
    from app.services import dadata

    with _patch_settings(token=None, secret="fake-secret"):
        # Не используем mock_transport — если код всё-таки попробует httpx,
        # это упадёт на конкретной сети (мы это поймаем в assert ниже).
        with patch("app.services.dadata.httpx.AsyncClient") as mock_client:
            result = await dadata.clean_address("Малышева 125")

    assert result is None
    mock_client.assert_not_called()


async def test_clean_address_returns_none_when_secret_missing() -> None:
    """DADATA_API_SECRET пустая строка → None."""
    from app.services import dadata

    with _patch_settings(token="fake-token", secret=""):
        with patch("app.services.dadata.httpx.AsyncClient") as mock_client:
            result = await dadata.clean_address("Малышева 125")

    assert result is None
    mock_client.assert_not_called()


async def test_clean_address_returns_none_when_address_too_short() -> None:
    """Адрес < 3 символов → None, никакого вызова DaData."""
    from app.services import dadata

    with _patch_settings():
        with patch("app.services.dadata.httpx.AsyncClient") as mock_client:
            result = await dadata.clean_address("a")
            assert result is None
            result_blank = await dadata.clean_address("")
            assert result_blank is None
    mock_client.assert_not_called()


# ── network failures → None ─────────────────────────────────────────────────


async def test_clean_address_returns_none_on_timeout() -> None:
    """httpx TimeoutException → None gracefully."""
    from app.services import dadata

    def handler(request: httpx.Request) -> httpx.Response:
        raise httpx.TimeoutException("read timed out")

    transport = httpx.MockTransport(handler)
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Малышева 125")

    assert result is None


async def test_clean_address_returns_none_on_network_error() -> None:
    """httpx NetworkError (DNS / connection refused) → None."""
    from app.services import dadata

    def handler(request: httpx.Request) -> httpx.Response:
        raise httpx.NetworkError("connection refused")

    transport = httpx.MockTransport(handler)
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Малышева 125")

    assert result is None


# ── HTTP errors → None ──────────────────────────────────────────────────────


@pytest.mark.parametrize("status", [429, 401, 403, 500, 502, 503])
async def test_clean_address_returns_none_on_http_error(status: int) -> None:
    """Любая 4xx/5xx → None (gracefully degrade)."""
    from app.services import dadata

    transport = _mock_transport_returning(status, {"error": "rejected"})
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Малышева 125")

    assert result is None


# ── bad response shapes → None ──────────────────────────────────────────────


async def test_clean_address_returns_none_when_response_is_empty_array() -> None:
    """[] → None."""
    from app.services import dadata

    transport = _mock_transport_returning(200, [])
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Малышева 125")

    assert result is None


async def test_clean_address_returns_none_when_response_is_dict_not_list() -> None:
    """Dict вместо list → None (DaData всегда отдаёт list)."""
    from app.services import dadata

    transport = _mock_transport_returning(200, {"result": "wrong shape"})
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Малышева 125")

    assert result is None


async def test_clean_address_returns_none_when_item_is_not_dict() -> None:
    """[\"string\"] вместо [{...}] → None."""
    from app.services import dadata

    transport = _mock_transport_returning(200, ["not a dict"])
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Малышева 125")

    assert result is None


async def test_clean_address_returns_none_when_canonical_address_missing() -> None:
    """DaData отдал shape, но result=None → не распознан, None."""
    from app.services import dadata

    payload = [{"result": None, "qc_geo": 5, "qc_house": None}]
    transport = _mock_transport_returning(200, payload)
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("какая-то ерунда")

    assert result is None


async def test_clean_address_returns_none_on_invalid_json() -> None:
    """Сервер ответил 200, но body не JSON → None."""
    from app.services import dadata

    def handler(request: httpx.Request) -> httpx.Response:
        return httpx.Response(200, content=b"<html>not json</html>")

    transport = httpx.MockTransport(handler)
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Малышева 125")

    assert result is None


# ── partial payload handling ─────────────────────────────────────────────────


async def test_clean_address_handles_partial_payload_without_cadnum() -> None:
    """Адрес распознан (есть `result`), но дома нет в ФИАС → cadnum=None, всё равно success."""
    from app.services import dadata

    partial = [
        {
            "result": "г Екатеринбург, ул Несуществующая, д 999",
            "house_cadnum": None,
            "house_fias_id": None,
            "geo_lat": "56.84",
            "geo_lon": "60.65",
            "qc_geo": 1,  # only street found
            "qc_house": 5,  # дом не найден
            "metro": None,
        }
    ]
    transport = _mock_transport_returning(200, partial)
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Несуществующая 999")

    assert result is not None
    assert result.canonical_address == "г Екатеринбург, ул Несуществующая, д 999"
    assert result.house_cadnum is None
    assert result.house_fias_id is None
    assert result.qc_geo == 1
    assert result.qc_house == 5
    # metro=None coerce'нулся в пустой список
    assert result.metro == []


async def test_clean_address_coerces_string_quality_codes_to_int() -> None:
    """Иногда DaData отдаёт qc_geo строкой '0' → должно стать int."""
    from app.services import dadata

    payload = [
        {
            "result": "г Екатеринбург, ул Малышева, д 125",
            "qc_geo": "0",
            "qc_house": "2",
            "geo_lat": "56.84",
            "geo_lon": "60.65",
        }
    ]
    transport = _mock_transport_returning(200, payload)
    with _patch_settings(), _patch_async_client(transport):
        result = await dadata.clean_address("Малышева 125")

    assert result is not None
    assert result.qc_geo == 0
    assert result.qc_house == 2


async def test_clean_address_sends_proper_request_body() -> None:
    """Тело запроса — array из одного элемента: [address]. Содержит правильный текст."""
    from app.services import dadata

    captured: dict[str, object] = {}

    def handler(request: httpx.Request) -> httpx.Response:
        import json as _json

        captured["body"] = _json.loads(request.content.decode("utf-8"))
        captured["auth"] = request.headers.get("Authorization")
        captured["secret"] = request.headers.get("X-Secret")
        return httpx.Response(200, json=SAMPLE_OK_PAYLOAD)

    transport = httpx.MockTransport(handler)
    with _patch_settings(token="my-token", secret="my-secret"), _patch_async_client(transport):
        result = await dadata.clean_address("  Екатеринбург, Малышева 125  ")

    assert result is not None
    assert captured["body"] == ["Екатеринбург, Малышева 125"]  # trimmed
    assert captured["auth"] == "Token my-token"
    assert captured["secret"] == "my-secret"