"""Publication must preserve the current dataset until every replacement is ready."""
import asyncio
import pandas as pd
import pytest
from fastapi.testclient import TestClient
from backend import app as api, data_loader
from backend.tests.test_sixth_form_flag import _schools_df


@pytest.fixture
def client(monkeypatch):
    old = _schools_df()
    monkeypatch.setattr(data_loader, '_df_cache', old)
    monkeypatch.setattr(data_loader, '_df_latest_cache', old)
    monkeypatch.setattr(api, '_place_registry', {'old': 'registry'})
    monkeypatch.setattr(api, '_place_index', {'old': 'index'})
    monkeypatch.setattr(api, '_place_index_source', api._place_registry)
    monkeypatch.setattr(api, '_sitemaps', {'old.xml': 'old sitemap'})
    monkeypatch.setattr(api, '_publication_lock', asyncio.Lock())
    monkeypatch.setattr(api.limiter, 'enabled', False)
    api.app.dependency_overrides[api.verify_admin_api_key] = lambda: True
    yield TestClient(api.app, raise_server_exceptions=False)
    api.app.dependency_overrides.clear()


def state():
    return (data_loader._df_cache, data_loader._df_latest_cache, api._place_registry,
            api._place_index, api._place_index_source, api._sitemaps)


@pytest.mark.parametrize('failure', ['empty', 'database', 'sitemap', 'duplicate'])
def test_failed_reload_preserves_every_published_object(client, monkeypatch, failure):
    before = state()
    df = _schools_df()
    if failure == 'empty':
        df = pd.DataFrame()
    if failure == 'duplicate':
        df = pd.concat([df, df.iloc[:1]], ignore_index=True)
    def load():
        if failure == 'database':
            raise RuntimeError('database unavailable')
        return df
    monkeypatch.setattr(api, 'load_school_data_as_dataframe', load)
    if failure == 'sitemap':
        monkeypatch.setattr(api, 'build_sitemaps', lambda *args: (_ for _ in ()).throw(RuntimeError('bad XML')))
    response = client.post('/api/admin/reload')
    assert response.status_code == 503
    assert all(a is b for a, b in zip(before, state()))


def test_success_publishes_school_data_places_and_sitemaps(client, monkeypatch):
    df = _schools_df()
    df.loc[0, 'school_name'] = 'Replacement School'
    monkeypatch.setattr(api, 'load_school_data_as_dataframe', lambda: df)
    response = client.post('/api/admin/reload')
    assert response.status_code == 200
    assert data_loader.load_school_data() is df
    assert data_loader.load_latest_school_data().iloc[0].school_name == 'Replacement School'
    assert api._place_index_source is api._place_registry
    assert 'old.xml' not in api._sitemaps
    assert 'replacement-school' in api._sitemaps['schools-1.xml']


def test_failed_sitemap_regeneration_keeps_existing_publication(client, monkeypatch):
    before = state()
    monkeypatch.setattr(api, 'build_sitemaps', lambda *args: (_ for _ in ()).throw(RuntimeError('bad XML')))
    assert client.post('/api/admin/regenerate-sitemap').status_code == 503
    assert all(a is b for a, b in zip(before, state()))