"""Route-level tests over the FastAPI app with the weather/geocode layer faked —
they exercise the real routing, validation, derived-store and ETag plumbing, and
would catch wiring regressions (e.g. a handler calling a deleted helper)."""
import pandas as pd
import pytest
from fastapi.testclient import TestClient

import app as appmod
import climate


@pytest.fixture
def client(monkeypatch, history, recent):
    monkeypatch.setattr(climate, "get_history",
                        lambda cell: (history.copy(), {"cached": True, "cache_age_days": 3}))
    monkeypatch.setattr(climate, "get_recent_forecast", lambda cell: recent.copy())
    monkeypatch.setattr(climate, "load_cached_history", lambda cell: history.copy())
    monkeypatch.setattr(climate, "recent_stamp", lambda cell_id: "rs-test")
    monkeypatch.setattr(climate, "reverse_geocode", lambda lat, lon: "Testville, Washington")
    return TestClient(appmod.app)


Q = {"lat": 47.6062, "lon": -122.3321}


def test_place_serves_any_point_worldwide(client):
    for q in (Q, {"lat": 48.8566, "lon": 2.3522}, {"lat": -33.8688, "lon": 151.2093}):
        r = client.get("/thermograph/api/v2/place", params=q)
        assert r.status_code == 200
        assert r.json()["place"] == "Testville, Washington"
        assert set(r.json()["cell"]) == {"center_lat", "center_lon"}


def test_grade_shape_and_conditional_revalidation(client, history):
    r = client.get("/thermograph/api/v2/grade", params=Q)
    assert r.status_code == 200
    body = r.json()
    assert body["place"] == "Testville, Washington"
    assert body["climatology"]["tmax"] is not None
    days = [d["date"] for d in body["recent"]]
    assert days == sorted(days, reverse=True)   # newest first
    assert body["recent"][0]["tmax"]["grade"]

    etag = r.headers["etag"]
    r304 = client.get("/thermograph/api/v2/grade", params=Q,
                      headers={"If-None-Match": etag})
    assert r304.status_code == 304 and r304.headers["etag"] == etag

    # Without the validator the derived store replays the exact same bytes.
    r2 = client.get("/thermograph/api/v2/grade", params=Q)
    assert r2.status_code == 200 and r2.content == r.content


def test_grade_is_aliased_across_api_versions(client):
    for prefix in ("api", "api/v1", "api/v2"):
        assert client.get(f"/thermograph/{prefix}/grade", params=Q).status_code == 200


def test_query_validation_rejects_out_of_range(client):
    assert client.get("/thermograph/api/v2/grade",
                      params={"lat": 999, "lon": 0}).status_code == 422
    assert client.get("/thermograph/api/v2/grade",
                      params={**Q, "days": 0}).status_code == 422


def test_day_detail_and_ladders(client, history):
    r = client.get("/thermograph/api/v2/day", params=Q)
    assert r.status_code == 200
    body = r.json()
    assert body["latest"] == pd.Timestamp(history["date"].max()).date().isoformat()
    tmax = body["detail"]["metrics"]["tmax"]
    assert tmax["ladder"]["tiers"][0]["c"] == "rec-hot"
    assert tmax["obs"]["grade"]


@pytest.mark.parametrize("path", ["grade", "calendar", "day", "forecast", "cell"])
def test_every_data_route_maps_rate_limit_to_503(client, monkeypatch, path):
    def rate_limited(cell):
        raise climate.WeatherUnavailable(climate.limit_message(False))
    monkeypatch.setattr(climate, "get_history", rate_limited)
    # A distinct spot per route: a store row cached by an earlier test would
    # otherwise be checked only after the (failing) history fetch anyway.
    r = client.get(f"/thermograph/api/v2/{path}", params={"lat": 51.5, "lon": -0.1})
    assert r.status_code == 503
    assert "rate-limited" in r.json()["detail"]


def test_upstream_failure_classification(client, monkeypatch):
    q = {"lat": 52.52, "lon": 13.4}

    def daily_quota(cell):
        raise climate.WeatherUnavailable(climate.limit_message(True), daily=True)
    monkeypatch.setattr(climate, "get_history", daily_quota)
    r = client.get("/thermograph/api/v2/grade", params=q)
    assert r.status_code == 503 and "tomorrow" in r.json()["detail"]

    # A raw upstream 429 that no fetcher classified still maps to a clean 503.
    def raw_429(cell):
        e = RuntimeError("upstream said no")
        e.response = type("R", (), {"status_code": 429})()
        raise e
    monkeypatch.setattr(climate, "get_history", raw_429)
    r = client.get("/thermograph/api/v2/grade", params=q)
    assert r.status_code == 503 and "rate-limited" in r.json()["detail"]

    # Anything else is a genuine upstream fault: 502 with the raw error.
    def boom(cell):
        raise RuntimeError("parquet cache corrupted")
    monkeypatch.setattr(climate, "get_history", boom)
    r = client.get("/thermograph/api/v2/grade", params=q)
    assert r.status_code == 502 and "parquet cache corrupted" in r.json()["detail"]


def test_cell_prefetch_never_fetches_upstream(client, monkeypatch):
    def boom(cell):
        raise AssertionError("prefetch=1 must never fetch weather upstream")
    monkeypatch.setattr(climate, "get_history", boom)
    monkeypatch.setattr(climate, "get_recent_forecast", boom)
    monkeypatch.setattr(climate, "load_cached_history", lambda cell: None)
    r = client.get("/thermograph/api/v2/cell", params={**Q, "prefetch": 1})
    assert r.status_code == 204   # cold cell: no body, no quota spent


def test_cell_prefetch_builds_history_slices_only(client):
    r = client.get("/thermograph/api/v2/cell", params={"lat": 10.0, "lon": 10.0, "prefetch": 1})
    assert r.status_code == 200
    assert set(r.json()["slices"]) == {"calendar", "day"}


def test_calendar_placeless_payload_is_not_persisted(client, monkeypatch):
    q = {"lat": -10.0, "lon": 20.0, "months": 2}
    monkeypatch.setattr(climate, "reverse_geocode", lambda lat, lon: None)
    r = client.get("/thermograph/api/v2/calendar", params=q)
    assert r.status_code == 200 and r.json()["place"] is None
    # The placeless payload wasn't cached, so the next request retries the
    # label instead of replaying bare coordinates for the life of the token.
    monkeypatch.setattr(climate, "reverse_geocode", lambda lat, lon: "Resolved, Now")
    assert client.get("/thermograph/api/v2/calendar", params=q).json()["place"] == "Resolved, Now"


def test_calendar_compact_range(client, history):
    r = client.get("/thermograph/api/v2/calendar", params={**Q, "months": 2})
    assert r.status_code == 200
    body = r.json()
    assert body["range"]["end"] == pd.Timestamp(history["date"].max()).date().isoformat()
    day = body["days"][0]
    assert {"date", "dsr", "tmax", "tmin", "precip"} <= set(day)
    assert set(day["tmax"]) == {"v", "pct", "c", "g"}


def test_forecast_grades_future_days(client):
    r = client.get("/thermograph/api/v2/forecast", params=Q)
    assert r.status_code == 200
    body = r.json()
    assert body["forecast"] is True
    days = [d["date"] for d in body["recent"]]
    assert days and days == sorted(days, reverse=True)   # furthest-out first
    assert min(days) > body["target_date"]               # strictly future


def test_cell_bundle_matches_per_view_payloads(client):
    r = client.get("/thermograph/api/v2/cell", params=Q)
    assert r.status_code == 200
    slices = r.json()["slices"]
    assert set(slices) == {"calendar", "grade", "forecast", "day"}
    for s in slices.values():
        assert s["etag"] and s["data"]
    # The grade slice must be byte-for-byte what /grade serves (same store row).
    grade = client.get("/thermograph/api/v2/grade", params=Q)
    assert grade.json() == slices["grade"]["data"]
    assert grade.headers["etag"] == slices["grade"]["etag"]

    r304 = client.get("/thermograph/api/v2/cell", params=Q,
                      headers={"If-None-Match": r.headers["etag"]})
    assert r304.status_code == 304


def test_suggest_falls_back_to_upstream_geocoder(client, monkeypatch):
    upstream = [{"name": "Seattle", "admin1": "Washington", "country": "United States",
                 "country_code": "US", "lat": 47.6, "lon": -122.33, "population": 737015}]
    monkeypatch.setattr(climate, "geocode", lambda q, count=5: list(upstream))
    r = client.get("/thermograph/api/v2/suggest", params={"q": "seattle-fallback-probe"})
    assert r.status_code == 200
    body = r.json()
    assert body["results"][0]["name"] == "Seattle"
    assert body["corrected"] is None


def test_pages_serve_with_origin_filled_in(client):
    r = client.get("/thermograph/")
    assert r.status_code == 200
    assert "text/html" in r.headers["content-type"]
    assert "__ORIGIN__" not in r.text
    assert client.head("/thermograph/calendar").status_code == 200