"""Tests for ``ImportService.get_tracks``, which rebuilds tracks from an export.

Regression: an export whose manifest labels its own streams imports even when the service
never set ``Title.language``. When nothing supplies a language the import fails naming the
service rather than blaming the manifest URL. A direct-URL subtitle anywhere in the export
replaces the manifest's whole subtitle set, since the service side-loaded it precisely
because the manifest's copy was the worse one.
"""

from __future__ import annotations

import json
from pathlib import Path
from typing import Any, Optional
from unittest.mock import patch

import click
import pytest
import requests

from unshackle.core.import_service import ImportService
from unshackle.core.manifests import DASH

MPD_TEMPLATE = """<?xml version="1.0"?>
<MPD xmlns="urn:mpeg:dash:schema:mpd:2011" type="static" mediaPresentationDuration="PT10M">
  <Period id="1">
    <AdaptationSet contentType="video" mimeType="video/mp4"{lang}>
      <Representation id="{video_id}" codecs="avc1.640028" bandwidth="5000000" width="1920" height="1080">
        <BaseURL>v.mp4</BaseURL><SegmentBase indexRange="0-1"/>
      </Representation>
    </AdaptationSet>
    <AdaptationSet contentType="text" mimeType="text/vtt"{lang}>
      <Representation id="{sub_id}" bandwidth="1000"><BaseURL>s.vtt</BaseURL><SegmentBase indexRange="0-1"/></Representation>
    </AdaptationSet>
  </Period>
</MPD>
"""

# labelled by @lang; unlabelled but with Unified Streaming ids DASH derives a language from;
# and labelled by neither, which is the only shape that needs the title's language
MPD_WITH_LANG = MPD_TEMPLATE.format(lang=' lang="ja"', video_id="v1", sub_id="s1")
MPD_ID_LANG = MPD_TEMPLATE.format(lang="", video_id="video_eng=5000000", sub_id="text_eng=1000")
MPD_NO_LANG = MPD_TEMPLATE.format(lang="", video_id="v1", sub_id="s1")

URL_SUBTITLE = {
    "type": "Subtitle",
    "id": "sideloaded-en",
    "url": "https://example.invalid/en.srt",
    "language": "en",
    "descriptor": "URL",
    "codec": "SubRip",
}


def make_service(tmp_path: Path, language: Optional[str], tracks: Optional[dict[str, Any]] = None) -> ImportService:
    export = {
        "version": 2,
        "service": "EXAMPLE",
        "titles": {
            "movie-1": {
                "meta": {"type": "movie", "id": "movie-1", "name": "Example Movie", "year": 2024, "language": language},
                "manifest_url": "https://example.invalid/m.mpd",
                "manifest_type": "DASH",
                "tracks": tracks or {},
            }
        },
    }
    path = tmp_path / "export.json"
    path.write_text(json.dumps(export), encoding="utf8")
    return ImportService(click.Context(click.Command("dl")), "EXAMPLE", "movie-1", str(path))


def get_tracks(service: ImportService, mpd: str):
    with patch.object(DASH, "from_url", side_effect=lambda url, session=None, **kw: DASH.from_text(mpd, url)):
        return service.get_tracks(next(iter(service.get_titles())))


@pytest.mark.parametrize("mpd", [MPD_WITH_LANG, MPD_ID_LANG], ids=["lang-attribute", "language-in-rep-id"])
def test_manifest_supplies_language_without_title_language(tmp_path: Path, mpd: str) -> None:
    """A manifest that labels its own streams imports fine with no language in the export."""
    tracks = get_tracks(make_service(tmp_path, language=None), mpd)
    assert [str(t.language) for t in tracks.videos] == ["ja" if mpd is MPD_WITH_LANG else "en"]


@pytest.mark.parametrize("language", [None, "und"], ids=["missing", "und"])
def test_unlabelled_manifest_without_usable_language_blames_the_service(
    tmp_path: Path, language: Optional[str]
) -> None:
    """`und` is truthy and a valid tag, so it must be rejected as firmly as no language at all."""
    with pytest.raises(click.ClickException) as error:
        get_tracks(make_service(tmp_path, language=language), MPD_NO_LANG)
    assert "Title.language" in error.value.message
    assert "may have expired" not in error.value.message


def test_exported_url_subtitles_replace_the_manifests(tmp_path: Path) -> None:
    """Services drop the manifest's subtitles and side-load their own; importing both duplicates them."""
    tracks = get_tracks(make_service(tmp_path, "ja", {"sideloaded-en": URL_SUBTITLE}), MPD_WITH_LANG)
    assert [(t.id, t.descriptor.name) for t in tracks.subtitles] == [("sideloaded-en", "URL")]
    assert len(tracks.videos) == 1


def test_direct_url_subtitles_win_over_every_manifest_one(tmp_path: Path) -> None:
    """One side-loaded subtitle condemns the whole re-parsed set, including other languages."""
    manifest_sub = {
        "type": "Subtitle",
        "id": "s1",
        "url": "https://example.invalid/m.mpd",
        "language": "ja",
        "descriptor": "DASH",
        "codec": "WebVTT",
    }
    tracks = get_tracks(
        make_service(tmp_path, "ja", {"s1": manifest_sub, "sideloaded-en": URL_SUBTITLE}), MPD_WITH_LANG
    )
    assert [(t.id, t.descriptor.name) for t in tracks.subtitles] == [("sideloaded-en", "URL")]


def test_unreadable_exported_track_is_skipped(tmp_path: Path) -> None:
    """A track dict this build cannot rebuild must not take the whole import down with it."""
    unknown = {**URL_SUBTITLE, "id": "future", "codec": "CODEC_FROM_A_LATER_BUILD"}
    tracks = get_tracks(make_service(tmp_path, "ja", {"sideloaded-en": URL_SUBTITLE, "future": unknown}), MPD_WITH_LANG)
    assert [t.id for t in tracks.subtitles] == ["sideloaded-en"]


@pytest.mark.parametrize(
    "failure",
    [requests.ConnectionError("dns"), TypeError("Expected 'MPD' document, but received a 'html' document instead.")],
    ids=["connection-error", "expired-token-html-page"],
)
def test_fetch_failure_still_reports_a_possible_expiry(tmp_path: Path, failure: Exception) -> None:
    """An expired signed URL can 200 with an error page, so document failures are expiries too."""
    service = make_service(tmp_path, "ja")
    title = next(iter(service.get_titles()))
    with patch.object(DASH, "from_url", side_effect=failure):
        with pytest.raises(click.ClickException) as error:
            service.get_tracks(title)
    assert "may have expired" in error.value.message