"""Контрактный тест «схема ↔ реализация»: каждый эндпоинт сверяется со схемой из docs/openapi.yaml.

Любое расхождение (лишнее поле, неверный тип, отсутствующая обязательная ветка,
утечка writeOnly-секрета) — падение с указанием пути до поля.
"""

from __future__ import annotations

from typing import Any

import pytest
from fastapi.testclient import TestClient
from starlette.websockets import WebSocketDisconnect

from awg_api.app import create_app
from awg_api.contract import (
    ContractViolationError,
    assert_routes_match,
    response_schema,
    validator_for,
    validate_response,
)
from awg_api.state import PRIVATE_KEY_SENTINEL, PRESHARED_KEY_SENTINEL, MockState

RULE_ID_PATH = "/api/v1/routing/rules/{rule_id}"
LEAKED_KEY = "NEW-PRIVATE-KEY-MUST-NOT-LEAK"
SECRET_SENTINELS = (PRIVATE_KEY_SENTINEL, PRESHARED_KEY_SENTINEL, LEAKED_KEY)
SECRET_FIELD_NAMES = ("private_key", "preshared_key", "password")

TUNNEL_PAYLOAD: dict[str, Any] = {
    "address": "10.8.0.9/32",
    "listen_port": 51821,
    "mtu": 1420,
    "private_key": LEAKED_KEY,
    "dns": ["10.8.0.1"],
}
ROUTING_PAYLOAD: dict[str, Any] = {
    "mode": "all-vpn",
    "kill_switch": True,
    "mtu_clamping": True,
    "ipv6": "block",
    "geoip": {"source": "cache", "prefix_count": 11412, "updated_at": None},
}
RULE_PAYLOAD: dict[str, Any] = {
    "name": "Правило контрактного теста",
    "kind": "domain",
    "value": "contract.example.net",
    "action": "vpn",
}
IMPORT_PAYLOAD: dict[str, Any] = {
    "format": "amneziawg-conf",
    "content": "[Peer]\nPublicKey = abc\nPresharedKey = def\n",
}

# (метод, путь, тело) — успешный путь для каждой операции контракта.
HAPPY_PATHS: tuple[tuple[str, str, dict[str, Any] | None], ...] = (
    ("get", "/api/v1/health", None),
    ("get", "/api/v1/ready", None),
    ("get", "/metrics", None),
    ("get", "/api/v1/status", None),
    ("get", "/api/v1/config", None),
    ("put", "/api/v1/config", {"tunnel": TUNNEL_PAYLOAD}),
    ("post", "/api/v1/config/validate", {"tunnel": TUNNEL_PAYLOAD}),
    ("get", "/api/v1/routing/rules", None),
    ("post", "/api/v1/routing/rules", RULE_PAYLOAD),
    ("put", "/api/v1/routing/mode", {"mode": "dns"}),
    ("post", "/api/v1/routing/geoip/update", {"force": True}),
    ("post", "/api/v1/routing/import", IMPORT_PAYLOAD),
    ("get", "/api/v1/devices", None),
    ("get", "/api/v1/logs", None),
    ("get", "/api/v1/auth/session", None),
    ("post", "/api/v1/auth/logout", None),
    ("post", "/api/v1/auth/login", {"username": "admin", "password": "awg-dash-dev-password"}),
)

EXPECTED_STATUS: dict[tuple[str, str], int] = {("post", "/api/v1/routing/rules"): 201}


def _check(spec: dict[str, Any], method: str, path: str, response: Any) -> None:
    """Валидирует ответ против схемы контракта (JSON — как объект, иначе — как текст)."""
    content_type = response.headers.get("content-type", "")
    payload = response.json() if content_type.startswith("application/json") else response.text
    validate_response(spec, path, method, response.status_code, payload)


def test_every_spec_operation_is_implemented(spec: dict[str, Any], app: Any) -> None:
    assert_routes_match(spec, app)


def test_openapi_json_serves_the_contract(client: TestClient, spec: dict[str, Any]) -> None:
    response = client.get("/openapi.json")
    assert response.status_code == 200
    assert response.json() == spec


@pytest.mark.parametrize(("method", "path", "body"), HAPPY_PATHS)
def test_success_response_matches_spec(
    spec: dict[str, Any],
    client: TestClient,
    auth_headers: dict[str, str],
    method: str,
    path: str,
    body: dict[str, Any] | None,
) -> None:
    response = client.request(method.upper(), path, json=body, headers=auth_headers)
    expected = EXPECTED_STATUS.get((method, path), 200)
    assert response.status_code == expected, f"{method.upper()} {path}: {response.status_code} {response.text}"
    _check(spec, method, path, response)


def test_rule_crud_cycle_matches_spec(spec: dict[str, Any], client: TestClient, auth_headers: dict[str, str]) -> None:
    created = client.post("/api/v1/routing/rules", json=RULE_PAYLOAD, headers=auth_headers)
    assert created.status_code == 201, created.text
    _check(spec, "post", "/api/v1/routing/rules", created)
    rule_id = created.json()["id"]

    fetched = client.get(f"/api/v1/routing/rules/{rule_id}", headers=auth_headers)
    assert fetched.status_code == 200
    _check(spec, "get", RULE_ID_PATH, fetched)

    updated = client.put(f"/api/v1/routing/rules/{rule_id}", json={"enabled": False}, headers=auth_headers)
    assert updated.status_code == 200
    assert updated.json()["enabled"] is False
    _check(spec, "put", RULE_ID_PATH, updated)

    deleted = client.delete(f"/api/v1/routing/rules/{rule_id}", headers=auth_headers)
    assert deleted.status_code == 204
    assert deleted.content == b""


def test_rules_list_filters_match_spec(spec: dict[str, Any], client: TestClient, auth_headers: dict[str, str]) -> None:
    response = client.get("/api/v1/routing/rules", params={"enabled": "true", "kind": "cidr"}, headers=auth_headers)
    assert response.status_code == 200
    payload = response.json()
    assert all(rule["kind"] == "cidr" and rule["enabled"] for rule in payload["items"])
    _check(spec, "get", "/api/v1/routing/rules", response)


def test_logs_pagination_matches_spec(spec: dict[str, Any], client: TestClient, auth_headers: dict[str, str]) -> None:
    first = client.get("/api/v1/logs", params={"limit": 2}, headers=auth_headers)
    assert first.status_code == 200
    payload = first.json()
    assert len(payload["items"]) == 2
    assert payload["next_cursor"] is not None
    _check(spec, "get", "/api/v1/logs", first)

    second = client.get(
        "/api/v1/logs",
        params={"limit": 2, "cursor": payload["next_cursor"], "level": "info"},
        headers=auth_headers,
    )
    assert second.status_code == 200
    assert all(entry["level"] == "info" for entry in second.json()["items"])
    _check(spec, "get", "/api/v1/logs", second)


@pytest.mark.parametrize(
    ("method", "path", "body", "expected_status", "expected_code"),
    (
        ("get", "/api/v1/status", None, 401, "unauthorized"),
        ("get", "/api/v1/config", None, 401, "unauthorized"),
        ("get", "/api/v1/routing/rules", None, 401, "unauthorized"),
        ("get", "/api/v1/devices", None, 401, "unauthorized"),
        ("get", "/api/v1/logs", None, 401, "unauthorized"),
        ("post", "/api/v1/routing/rules", {"name": "x", "kind": "domain", "value": "x", "action": "vpn"}, 401, "unauthorized"),
        (
            "put",
            "/api/v1/config",
            {"tunnel": {**TUNNEL_PAYLOAD, "unknown_field": 1}},
            422,
            "validation_failed",
        ),
        ("post", "/api/v1/config/validate", {"tunnel": {"address": "10.8.0.2/32", "listen_port": 99999}}, 422, "validation_failed"),
        ("post", "/api/v1/routing/rules", {"name": "", "kind": "nope", "value": "x"}, 422, "validation_failed"),
        ("put", "/api/v1/routing/mode", {"mode": "turbo"}, 422, "validation_failed"),
        ("post", "/api/v1/auth/login", {"username": "admin", "password": "wrong"}, 401, "unauthorized"),
        ("post", "/api/v1/auth/login", {"username": "", "password": ""}, 422, "validation_failed"),
        ("get", "/api/v1/logs", None, 422, "validation_failed"),
    ),
)
def test_error_response_matches_error_schema(
    spec: dict[str, Any],
    client: TestClient,
    auth_headers: dict[str, str],
    method: str,
    path: str,
    body: dict[str, Any] | None,
    expected_status: int,
    expected_code: str,
) -> None:
    headers = dict(auth_headers)
    params: dict[str, Any] = {}
    if expected_status == 401 and path != "/api/v1/auth/login":
        headers = {}
    if path == "/api/v1/logs" and expected_status == 422:
        params = {"cursor": "not-a-number"}
    response = client.request(method.upper(), path, json=body, headers=headers, params=params)
    assert response.status_code == expected_status, response.text
    payload = response.json()
    assert payload["code"] == expected_code
    assert set(payload) == {"code", "message", "details"}
    _check(spec, method, path, response)


def test_not_found_rule_matches_error_schema(
    spec: dict[str, Any], client: TestClient, auth_headers: dict[str, str]
) -> None:
    missing = "00000000-0000-4000-8000-000000000000"
    url = f"/api/v1/routing/rules/{missing}"
    responses = [
        ("get", client.get(url, headers=auth_headers)),
        ("put", client.put(url, json={"enabled": True}, headers=auth_headers)),
        ("delete", client.delete(url, headers=auth_headers)),
    ]
    for method, response in responses:
        assert response.status_code == 404, response.text
        assert response.json()["code"] == "not_found"
        _check(spec, method, RULE_ID_PATH, response)


def test_conflict_on_duplicate_rule_matches_error_schema(
    spec: dict[str, Any],
    client: TestClient,
    auth_headers: dict[str, str],
) -> None:
    first = client.post("/api/v1/routing/rules", json=RULE_PAYLOAD, headers=auth_headers)
    assert first.status_code == 201
    duplicate = client.post("/api/v1/routing/rules", json=RULE_PAYLOAD, headers=auth_headers)
    assert duplicate.status_code == 409
    assert duplicate.json()["code"] == "conflict"
    _check(spec, "post", "/api/v1/routing/rules", duplicate)


def test_ready_503_matches_error_schema(spec: dict[str, Any], token: str) -> None:
    app = create_app(state=MockState(ready=False), token=token)
    with TestClient(app) as client:
        response = client.get("/api/v1/ready")
        assert response.status_code == 503
        assert response.json()["code"] == "agent_unavailable"
        _check(spec, "get", "/api/v1/ready", response)
        health = client.get("/api/v1/health")
        assert health.status_code == 200
        assert health.json()["status"] == "degraded"
        _check(spec, "get", "/api/v1/health", health)


def test_validate_endpoint_reports_issues_without_applying(
    spec: dict[str, Any],
    client: TestClient,
    auth_headers: dict[str, str],
) -> None:
    response = client.post(
        "/api/v1/config/validate",
        json={"tunnel": {"address": "10.8.0.2", "listen_port": 51820, "mtu": 1500, "private_key": "k"}},
        headers=auth_headers,
    )
    assert response.status_code == 200, response.text
    payload = response.json()
    assert payload["valid"] is False
    assert {issue["code"] for issue in payload["errors"]} == {"invalid_cidr"}
    assert {issue["severity"] for issue in payload["warnings"]} == {"warning"}
    _check(spec, "post", "/api/v1/config/validate", response)


def test_metrics_endpoint_returns_prometheus_text(
    spec: dict[str, Any],
    client: TestClient,
) -> None:
    response = client.get("/metrics")
    assert response.status_code == 200
    assert response.headers["content-type"].startswith("text/plain")
    assert "awg_dash_tunnel_up 1" in response.text
    _check(spec, "get", "/metrics", response)


def test_responses_contain_no_secret_material(
    spec: dict[str, Any],
    client: TestClient,
    auth_headers: dict[str, str],
) -> None:
    """AC: в ответах нет приватных ключей — ни значений, ни имён полей."""
    responses = [
        client.get("/api/v1/config", headers=auth_headers),
        client.put("/api/v1/config", json={"tunnel": TUNNEL_PAYLOAD}, headers=auth_headers),
        client.get("/api/v1/status", headers=auth_headers),
        client.get("/api/v1/devices", headers=auth_headers),
        client.get("/api/v1/logs", headers=auth_headers),
        client.get("/api/v1/auth/session", headers=auth_headers),
        client.post("/api/v1/auth/logout", headers=auth_headers),
    ]
    for response in responses:
        body = response.text
        for sentinel in SECRET_SENTINELS:
            assert sentinel not in body, f"утечка секрета {sentinel} в {response.request.url}"
        for field in SECRET_FIELD_NAMES:
            assert field not in body, f"поле {field} присутствует в ответе {response.request.url}"


def test_websocket_frames_match_spec(spec: dict[str, Any], client: TestClient, token: str) -> None:
    frame_schema = spec["components"]["schemas"]["WsFrame"]
    metrics_schema = spec["components"]["schemas"]["MetricsSample"]
    frame_validator = validator_for(frame_schema, spec)
    data_validator = validator_for(metrics_schema, spec)
    with client.websocket_connect(f"/api/v1/metrics/stream?token={token}&interval_ms=250") as websocket:
        frame = websocket.receive_json()
    assert list(frame_validator.iter_errors(frame)) == []
    assert frame["type"] == "metrics"
    assert list(data_validator.iter_errors(frame["data"])) == []


def test_websocket_requires_token(client: TestClient) -> None:
    with pytest.raises(WebSocketDisconnect), client.websocket_connect("/api/v1/metrics/stream") as websocket:
        websocket.receive_json()


def test_response_schema_lookup_fails_for_unknown_response(spec: dict[str, Any], client: TestClient) -> None:
    """Неописанный в контракте ответ — ошибка контракта, не молчаливый пропуск."""
    response = client.get("/api/v1/health")
    with pytest.raises(ContractViolationError):
        validate_response(spec, "/api/v1/health", "get", 418, response.json())
    assert response_schema(spec, "/api/v1/health", "get", 418) is None