"""E22.5 S4 — yt-dlp explains itself to our log, not to a stdout nobody reads.

`quiet: True` was doing more than quieting: with no `logger`, yt-dlp's whole account of a download
went to the child process's stdout, so "Requested format is not available", a signature-extraction
failure or a POT refusal reached us only as whatever text happened to end up in the raised
exception. A failed download's real reason was routinely one line the app never kept.

Measured against yt-dlp 2026.07.04 (the pinned version): with `logger` set, yt-dlp calls `debug`
for its extraction and progress lines and `warning`/`error` for the rest, and neither `quiet` nor
`no_warnings` gates those calls. The cases below pin what we do with them.
"""

import json
import logging

import pytest

from app import logs
from app.downloads import formats

URL = "https://www.youtube.com/watch?v=dQw4w9WgXcQ&list=PLsomething"


class _Sink(logging.Handler):
    """The stdout handler's own filter and formatter, so a case sees the bytes a deployment writes."""

    def __init__(self):
        super().__init__(level=logging.NOTSET)
        self.lines: list[str] = []
        self.setFormatter(logs.JsonFormatter())
        self.addFilter(logs.ContextFilter())

    def emit(self, record):
        self.lines.append(self.format(record))

    def objects(self) -> list[dict]:
        return [json.loads(line) for line in self.lines]


@pytest.fixture
def sink():
    logger = logging.getLogger("siftlode")
    handler = _Sink()
    previous = logger.level
    logger.addHandler(handler)
    logger.setLevel(logs.TRACE)
    try:
        yield handler
    finally:
        logger.removeHandler(handler)
        logger.setLevel(previous)


@pytest.mark.parametrize(
    ("method", "level"),
    [
        # Several lines per second during a download, and TRACE is the level a user turns on for
        # their own session — so the noisy half is exactly the half the consent gates.
        ("debug", "TRACE"),
        ("info", "DEBUG"),
        ("warning", "WARNING"),
        ("error", "ERROR"),
    ],
)
def test_each_ytdlp_level_lands_where_it_belongs(sink, method, level):
    getattr(formats._YDL_LOG, method)("something happened")

    (line,) = sink.objects()
    assert line["level"] == level
    assert line["event"] == "download.ytdlp"
    assert "something happened" in line["msg"]


def test_the_source_url_does_not_travel_with_the_explanation(sink):
    formats._YDL_LOG.error(f"ERROR: [youtube] {URL}: Requested format is not available")

    (line,) = sink.objects()
    # The host survives — it is what says which extractor is failing. The rest is a row of this
    # person's download history, and the job id already names the job on every one of these lines.
    assert "www.youtube.com/…" in line["msg"]
    assert "dQw4w9WgXcQ" not in json.dumps(line)
    assert "list=PLsomething" not in json.dumps(line)
    assert "Requested format is not available" in line["msg"]


def test_a_line_with_no_url_is_left_alone(sink):
    formats._YDL_LOG.warning("nsig extraction failed: Some formats may be missing")

    (line,) = sink.objects()
    assert "nsig extraction failed: Some formats may be missing" in line["msg"]


def test_the_download_options_carry_the_logger():
    opts = formats.build_ydl_opts({}, "%(id)s.%(ext)s", lambda d: None)

    assert opts["logger"] is formats._YDL_LOG


def test_a_source_adapter_cannot_silence_it():
    """`extra` is the adapter's own options (YouTube's player-client/POT strategy), merged wholesale.
    The logger is set after that merge for the same reason `cookiefile` and the size cap are: an
    adapter must not be able to take away the one account of what went wrong that a failed job
    leaves behind."""
    opts = formats.build_ydl_opts(
        {}, "%(id)s.%(ext)s", lambda d: None, extra={"logger": None, "quiet": False}
    )

    assert opts["logger"] is formats._YDL_LOG