"""GIAS publishes its extracts in Windows-1252 and declares no charset.

The tap used to hand pandas `resp.text`, so requests guessed the codec.
On 3 Oct 2026 it guessed windows-1250, and "St Thomas à Becket" was stored
as "St Thomas ŕ Becket". The `encoding=` passed to read_csv did nothing,
because the text was already decoded.
"""
import importlib.util
import logging
from pathlib import Path

import pytest

MODULE = (Path(__file__).resolve().parents[1] / 'plugins' / 'extractors' / 'tap-uk-gias'
          / 'tap_uk_gias' / 'gias_csv.py')


@pytest.fixture
def gias_csv():
    spec = importlib.util.spec_from_file_location('gias_csv', MODULE)
    module = importlib.util.module_from_spec(spec)
    spec.loader.exec_module(module)
    return module


# Byte for byte as GIAS writes it: 0xE0 à, 0x92 ’, 0xE9 é, 0xB0 °, 0xE7 ç.
EXTRACT = (
    b'"URN","EstablishmentName","HeadLastName"\r\n'
    b'"138950","St Thomas \xe0 Becket Catholic Secondary School","Smith"\r\n'
    b'"100000","The Dean and Chapter of St Paul\x92s Cathedral","Pr\xe9vert"\r\n'
    b'"140677","North Star 180\xb0","Fran\xe7ois"\r\n'
    b'"100001","No head recorded",""\r\n'
)


def test_names_decode_as_windows_1252(gias_csv):
    df = gias_csv.read_gias_csv(EXTRACT)
    assert list(df['EstablishmentName']) == [
        'St Thomas à Becket Catholic Secondary School',
        'The Dean and Chapter of St Paul’s Cathedral',
        'North Star 180°',
        'No head recorded',
    ]
    assert list(df['HeadLastName']) == ['Smith', 'Prévert', 'François', '']


def test_the_codec_requests_guessed_is_not_used(gias_csv):
    # What the tap stored on 3 Oct: the same bytes read as windows-1250.
    assert 'ŕ' in EXTRACT.decode('cp1250')
    names = ' '.join(gias_csv.read_gias_csv(EXTRACT)['EstablishmentName'])
    assert 'ŕ' not in names


def test_values_stay_strings(gias_csv):
    df = gias_csv.read_gias_csv(EXTRACT)
    assert df.loc[0, 'URN'] == '138950'


def test_a_byte_windows_1252_leaves_undefined_does_not_stop_the_load(gias_csv, caplog):
    # 0x81 has no Windows-1252 character. One odd name must not block the daily
    # refresh of every school, but it must be visible in the log.
    extract = b'"URN","EstablishmentName"\r\n"100002","Odd \x81 Name"\r\n'
    with caplog.at_level(logging.WARNING):
        df = gias_csv.read_gias_csv(extract, logger=logging.getLogger('gias'))
    assert df.loc[0, 'EstablishmentName'] == 'Odd � Name'
    assert 'could not be decoded' in caplog.text