"""Offline NaPTAN import, spatial lookup and API regression tests."""

from __future__ import annotations

import csv
from pathlib import Path

import pytest
import responses

from uk_bus_stops import core
from uk_bus_stops.app import create_app
from uk_bus_stops.naptan import NaptanError, NaptanStore, import_csv


@pytest.fixture()
def csv_file(tmp_path: Path) -> Path:
    """Write representative stop records, including grid-only and invalid data."""
    path = tmp_path / "Stops.csv"
    fields = ["ATCOCode", "CommonName", "StopType", "Status", "Latitude", "Longitude", "Easting", "Northing", "GridType", "Bearing", "Indicator"]
    records = [
        ["0100BRP90317", "Temple Meads Stn", "BCT", "active", "51.44827", "-2.58302", "359581", "172304", "UKOS", "SE", "T1"],
        ["0100GRID001", "Gare café", "RSE", "active", "", "", "359581", "172304", "", "", ""],
        ["0100INACTIVE", "Closed", "BCT", "inactive", "51.448", "-2.583", "", "", "", "", ""],
        ["0100INVALID", "Invalid", "BCT", "active", "nan", "0", "", "", "", "", ""],
        ["0100CORNER", "Outside radius", "FER", "active", "51.456", "-2.571", "", "", "", "", ""],
        ["0100EAST001", "East", "BCT", "active", "51.44827", "-2.57302", "", "", "", "", ""],
        ["0100NORTH01", "North", "BCT", "active", "51.45627", "-2.58302", "", "", "", "", ""],
    ]
    with path.open("w", encoding="utf-8-sig", newline="") as stream:
        writer = csv.writer(stream)
        writer.writerow(fields)
        writer.writerows(records)
    return path


@pytest.fixture()
def database(csv_file: Path, tmp_path: Path) -> Path:
    """Import an isolated database shared by query and API tests."""
    path = tmp_path / "naptan.sqlite3"
    assert import_csv(csv_file, path) == {"imported": 5, "inactive": 1, "invalid": 1, "converted": 1}
    return path


def test_import_and_exact_lookup(database: Path) -> None:
    """Preserve codes, accents, transport metadata and converted grid positions."""
    store = NaptanStore(database)
    stop = store.find_atco_code("0100brp90317")[0]
    assert stop["id"] == "0100BRP90317"
    assert stop["source"] == "NaPTAN"
    assert stop["bearing"] == "SE"
    assert stop["indicator"] == "T1"
    grid = store.find_atco_code("0100GRID001")[0]
    assert grid["name"] == "Gare café"
    assert grid["transport_type"] == "Railway station entrance"
    assert grid["lat"] == pytest.approx(stop["lat"], abs=0.0001)
    assert grid["lon"] == pytest.approx(stop["lon"], abs=0.0001)
    assert store.find_atco_code("0100INACTIVE") == []
    assert store.find_atco_code("' OR 1=1 --") == []


def test_spatial_search(database: Path) -> None:
    """Radius excludes box corners and orders longitude distances correctly."""
    store = NaptanStore(database)
    nearby = store.nearby_stops(51.44827, -2.58302)
    assert [stop["id"] for stop in nearby][-2:] == ["0100EAST001", "0100NORTH01"]
    assert "0100CORNER" not in {stop["id"] for stop in nearby}
    assert len(store.stops_in_bounds(51.448, -2.584, 51.449, -2.582)) == 2
    assert store.stops_in_bounds(51.44828, -2.583021, 51.44829, -2.583019) == []
    assert store.nearby_stops(0, 0) == []


def test_atomic_refresh_and_failed_import(database: Path, csv_file: Path) -> None:
    """Invalid refreshes preserve the old database; valid refreshes replace it."""
    original = csv_file.read_text(encoding="utf-8-sig")
    csv_file.write_text("invalid\n")
    with pytest.raises(NaptanError):
        import_csv(csv_file, database)
    store = NaptanStore(database)
    assert store.find_atco_code("0100BRP90317")[0]["name"] == "Temple Meads Stn"
    csv_file.write_text(original.replace("Temple Meads Stn", "Updated name"))
    import_csv(csv_file, database)
    assert store.find_atco_code("0100BRP90317")[0]["name"] == "Updated name"
    assert not list(database.parent.glob(".naptan-*"))


@responses.activate
def test_naptan_api_needs_no_network(database: Path) -> None:
    """Coordinate, viewport, code and shared stop requests all use local data."""
    client = create_app({"TESTING": True, "STOP_SOURCE": "naptan", "NAPTAN_DATABASE": str(database)}).test_client()
    for url in (
        "/api/search?q=0100brp90317",
        "/api/search?q=51.44827,-2.58302",
        "/api/stops?lat=51.44827&lon=-2.58302",
        "/api/stops/in-bounds?south=51.448&west=-2.584&north=51.449&east=-2.582",
    ):
        response = client.get(url)
        assert response.status_code == 200
        assert response.json["stops"][0]["source"] == "NaPTAN"
    response = client.get("/api/stop/naptan/0100brp90317")
    assert response.status_code == 200
    assert response.json["stop"]["id"] == "0100BRP90317"
    assert client.get("/api/stop/naptan/missing").status_code == 404
    assert len(responses.calls) == 0


def test_missing_database(tmp_path: Path) -> None:
    """An unconfigured installation explains how to import instead of creating a DB."""
    database = tmp_path / "missing.sqlite3"
    client = create_app({"TESTING": True, "NAPTAN_DATABASE": str(database), "STOP_SOURCE": "naptan"}).test_client()
    response = client.get("/api/stops?lat=51.45&lon=-2.58")
    assert response.status_code == 503
    assert response.json["error"] == "naptan_unavailable"
    assert not database.exists()


@responses.activate
def test_naptan_routes_match_atco_and_deduplicate(database: Path) -> None:
    """Multiple matching OSM objects contribute one combined route list."""
    responses.get(core.OVERPASS_URL, json={"elements": [
        {"type": "node", "id": 1, "lat": 51.448, "lon": -2.583},
        {"type": "way", "id": 2, "center": {"lat": 51.448, "lon": -2.583}},
    ]})
    for _ in range(2):
        responses.get(core.OVERPASS_URL, json={"elements": [
            {"id": 12, "tags": {"ref": "A1", "route": "bus"}},
        ]})
    client = create_app({"TESTING": True, "NAPTAN_DATABASE": str(database)}).test_client()
    response = client.get("/api/stop/naptan/0100BRP90317/routes")
    assert response.status_code == 200
    assert response.json["matched_stops"] == 2
    assert [route["ref"] for route in response.json["routes"]] == ["A1"]
    assert "0100BRP90317" in responses.calls[0].request.url


@responses.activate
def test_naptan_routes_without_osm_match(database: Path) -> None:
    """A missing OSM match has a distinct result from a service failure."""
    responses.get(core.OVERPASS_URL, json={"elements": []})
    client = create_app({"TESTING": True, "NAPTAN_DATABASE": str(database)}).test_client()
    assert client.get("/api/stop/naptan/0100BRP90317/routes").json == {
        "routes": [], "source": "OpenStreetMap", "matched_stops": 0,
    }
    responses.replace(responses.GET, core.OVERPASS_URL, status=503)
    responses.get(core.OVERPASS_FALLBACK_URLS[0], status=503)
    assert client.get("/api/stop/naptan/0100BRP90317/routes").status_code == 502
    assert client.get("/api/stop/naptan/0100BRP90317").status_code == 200