"""Tests for the homepage: the cache-only "unusual right now" precompute, the
server-rendered surfaces, and the digest signup.

The precompute must never touch the network — a sweep over ~1000 cities that
fetched would burst the archive quota — so the tests here assert that the
fetching climate helpers are not called at all.
"""
import datetime
import json
import pathlib
import time

import pytest
from fastapi.testclient import TestClient

import app as appmod
import cities
import climate
import content
import homepage

B = "/thermograph"


@pytest.fixture
def client():
    return TestClient(appmod.app)


@pytest.fixture
def no_feed(monkeypatch):
    """The homepage with no precomputed feed at all."""
    monkeypatch.setattr(homepage, "load", lambda: None)
    return None


def _pick(name, pct, cls, grade, tail, slug=None):
    return {
        "slug": slug or (name.lower().replace(" ", "-") + "-xx"),
        "name": name, "display": f"{name}, Somewhere",
        "lat": 1.0, "lon": 2.0, "cell_id": "1_2",
        "date": datetime.date.today().isoformat(),
        "metric": "tmax", "metric_label": "High temp", "window_label": "mid-July",
        "value": 99.0, "percentile": pct, "grade": grade, "cls": cls,
        "departure": abs(pct - 50), "tail": tail,
    }


# --- the precompute ----------------------------------------------------------
def test_build_never_fetches_upstream(monkeypatch):
    """The sweep uses the cache-only readers, never the fetching ones."""
    def boom(*a, **k):
        raise AssertionError("the homepage sweep must not fetch upstream")

    monkeypatch.setattr(climate, "get_history", boom)
    monkeypatch.setattr(climate, "get_recent_forecast", boom)
    feed = homepage.build(limit=20)
    assert set(feed) >= {"generated_at", "date", "considered", "picks", "ranked"}


def test_build_grades_cached_cities(monkeypatch, history, recent):
    monkeypatch.setattr(climate, "load_cached_history", lambda cell: history.clone())
    monkeypatch.setattr(climate, "load_cached_recent_forecast", lambda cell: recent.clone())
    feed = homepage.build(limit=5)
    assert feed["considered"] == 5
    for row in feed["ranked"]:
        assert row["percentile"] is not None
        assert row["cls"] and not row["cls"].startswith("--")   # token name, no prefix
        assert row["tail"] in ("warm", "cold")


def test_missing_cell_cache_is_skipped_not_fatal(monkeypatch):
    monkeypatch.setattr(climate, "load_cached_history", lambda cell: None)
    monkeypatch.setattr(climate, "load_cached_recent_forecast", lambda cell: None)
    feed = homepage.build(limit=10)
    assert feed["considered"] == 0 and feed["ranked"] == []


def test_load_survives_missing_and_corrupt_file(monkeypatch, tmp_path):
    monkeypatch.setattr(homepage, "FEED_PATH", str(tmp_path / "nope.json"))
    assert homepage.load() is None

    bad = tmp_path / "homepage.json"
    bad.write_text("{not json")
    monkeypatch.setattr(homepage, "FEED_PATH", str(bad))
    assert homepage.load() is None

    bad.write_text('{"unexpected": true}')
    assert homepage.load() is None


def test_refresh_writes_atomically(monkeypatch, tmp_path):
    monkeypatch.setattr(homepage, "FEED_PATH", str(tmp_path / "homepage.json"))
    monkeypatch.setattr(climate, "load_cached_history", lambda cell: None)
    homepage.refresh(limit=3)
    written = json.loads((tmp_path / "homepage.json").read_text())
    assert written["ranked"] == []
    # No temp files left behind.
    assert [p.name for p in tmp_path.iterdir()] == ["homepage.json"]


def test_staleness(monkeypatch):
    today = datetime.date.today().isoformat()
    assert not homepage.is_stale({"date": today, "generated_at": time.time()})
    assert homepage.is_stale({"date": today, "generated_at": time.time() - 7 * 3600})
    assert homepage.is_stale({"date": "1999-01-01", "generated_at": time.time()})


# --- the rendered page -------------------------------------------------------
def test_homepage_is_complete_without_js(client, no_feed):
    """A crawler (or a reader with JS off) gets the whole page as real HTML."""
    r = client.get(f"{B}/")
    assert r.status_code == 200
    html = r.text
    assert "How unusual is your weather?" in html
    assert "How it works" in html
    assert "Climate context for 1,000 cities" in html
    assert "Free. No ads. No tracking." in html
    # The interactive tool's DOM contract survives the move to Jinja.
    for dom_id in ('id="find-btn"', 'id="date-input"', 'id="panel"',
                   'id="placeholder"', 'id="results"'):
        assert dom_id in html
    # Exactly one h1: the hero headline. The brand degrades to a <p>.
    assert html.count("<h1") == 1
    assert 'p class="site-name"' in html


def test_hero_locate_has_a_status_slot(client, no_feed):
    """The locate button needs somewhere to report a declined prompt or a
    timeout. Without it the control fails silently, which is how it shipped
    broken: navigator.geolocation exists on plain http:// but always errors."""
    html = client.get(f"{B}/").text
    assert 'id="hero-locate"' in html
    assert 'id="hero-locate-msg"' in html
    assert 'aria-live="polite"' in html


def test_homepage_brand_keeps_the_lockup_styling(client, no_feed):
    """The homepage renders the brand as <p class="site-name"> so the hero owns
    the page's only h1. The lockup styling is written against `.brand h1`, so
    the class MUST be matched there too — otherwise the brand silently falls
    back to block layout, which baseline-aligns the mark instead of centring it
    and drops the monospace wordmark. Nothing else catches this: the page still
    renders, and every other test still passes, while the header looks wrong.
    """
    html = client.get(f"{B}/").text
    assert 'class="site-name"' in html
    assert "<h1 class=\"site-name\"" not in html      # the hero owns the h1

    css = (pathlib.Path(__file__).parents[2] / "frontend" / "style.css").read_text()
    lockup = css.split(".brand h1", 1)[1].split("}", 1)[0]
    assert ".brand .site-name" in lockup, (
        "the .brand h1 lockup rule must also match .brand .site-name"
    )


def test_city_chips_all_resolve(client, no_feed):
    """Every homepage chip must be a real, routable city — a stale slug would
    render an empty chip list and leak a 404 link."""
    resolved = content._home_cities()
    assert len(resolved) == len(content.HOME_CITY_SLUGS)
    html = client.get(f"{B}/").text
    for city in resolved:
        assert f"/climate/{city['slug']}" in html
        assert cities.get(city["slug"]) is not None


def test_records_strip_shows_both_tails(client, monkeypatch):
    """Two-sided honesty: a qualifying cold-tail city appears alongside the heat."""
    feed = {
        "generated_at": time.time(), "date": datetime.date.today().isoformat(),
        "considered": 800,
        "picks": {"extreme": _pick("Phoenix", 99.4, "rec-hot", "Near Record", "warm")},
        "ranked": [_pick("Phoenix", 99.4, "rec-hot", "Near Record", "warm"),
                   _pick("Ushuaia", 2.1, "very-cold", "Very Low", "cold")],
    }
    monkeypatch.setattr(homepage, "load", lambda: feed)
    html = client.get(f"{B}/").text
    assert "Unusual right now" in html
    assert "Phoenix" in html and "Ushuaia" in html
    # Band colour comes from the shared tokens, and the band word is always
    # present too — colour is never the only signal.
    assert "var(--rec-hot)" in html and "var(--very-cold)" in html
    assert "Near Record" in html and "Very Low" in html


def test_hero_uses_most_unusual_default(client, monkeypatch):
    feed = {
        "generated_at": time.time(), "date": datetime.date.today().isoformat(),
        "considered": 800,
        "picks": {"extreme": _pick("Phoenix", 96.0, "very-hot", "Very High", "warm")},
        "ranked": [],
    }
    monkeypatch.setattr(homepage, "load", lambda: feed)
    html = client.get(f"{B}/").text
    assert "Today in Phoenix, Somewhere" in html
    assert "96th percentile" in html
    assert "the most unusual weather we're tracking" in html


def test_homepage_renders_without_feed(client, no_feed):
    """A cold checkout with no precomputed feed still serves a complete page."""
    html = client.get(f"{B}/").text
    assert "How unusual is your weather?" in html
    assert "Unusual right now" not in html      # strip is omitted, not broken
    assert 'id="hero-grade"' in html            # the frame is still there


def test_homepage_etag_revalidates(client, no_feed):
    r = client.get(f"{B}/")
    etag = r.headers["etag"]
    again = client.get(f"{B}/", headers={"If-None-Match": etag})
    assert again.status_code == 304


def test_old_static_index_is_gone(client):
    """index.html must not linger behind the static mount as indexable duplicate
    content now that / is server-rendered."""
    assert client.get(f"{B}/index.html").status_code == 404


def test_privacy_page(client):
    r = client.get(f"{B}/privacy")
    assert r.status_code == 200
    assert "no analytics library" in r.text.lower() or "no analytics" in r.text.lower()
    assert "Use my location" in r.text


def test_privacy_is_linked_but_not_in_sitemap(client):
    assert f"{B}/privacy" in client.get(f"{B}/").text
    # It's a policy page, not a crawl target we want ranked.
    assert "/privacy" not in client.get(f"{B}/sitemap.xml").text