"""Tests for per-language subtitle selection and dict-typed ``Config.languages``.

These tests are pure: no network, no yt-dlp, no DB.  They cover the policy
logic that decides which subtitle track to pick for a given
``info`` dict produced by yt-dlp, plus the legacy/back-compat shims that
let older YAML configs still load.
"""
from __future__ import annotations

import pytest

from yt_scraper.config import Config, parse_languages
from yt_scraper.extract import pick_subtitle


# ---------- fixtures ----------

def _track(ext: str = "json3", url: str = "u") -> dict:
    return {"ext": ext, "url": url}


def _info(manual: dict | None = None, auto: dict | None = None) -> dict:
    return {"subtitles": manual or {}, "automatic_captions": auto or {}}


# ---------- pick_subtitle: mixed per-language mode ----------

def test_mixed_manual_and_auto_per_language() -> None:
    """`es: auto` only takes auto; iterating `es` first means it wins.

    With ``{"es": "auto", "en": "manual"}`` the iteration matches `es`
    against the auto dict and picks the auto track; for `en` only the
    manual dict is consulted and the manual track is returned.  The two
    policies do NOT cross-pollinate between languages.
    """
    info = _info(
        manual={"en": [_track(url="man-en")]},
        auto={"en": [_track(url="auto-en")], "es": [_track(url="auto-es")]},
    )
    pick = pick_subtitle(info, {"es": "auto", "en": "manual"}, prefer_manual=True)
    assert pick is not None
    assert pick.lang == "es"
    assert pick.source == "auto"


def test_manual_only_skips_auto_even_when_present() -> None:
    info = _info(manual={}, auto={"es": [_track(url="auto")]})
    pick = pick_subtitle(info, {"es": "manual"}, prefer_manual=True)
    assert pick is None


def test_auto_only_skips_manual_even_when_present() -> None:
    info = _info(manual={"es": [_track(url="man")]}, auto={})
    pick = pick_subtitle(info, {"es": "auto"}, prefer_manual=True)
    assert pick is None


def test_any_defer_to_prefer_manual_default_true() -> None:
    """`any` honours the legacy prefer_manual=True default."""
    info = _info(
        manual={"es": [_track(url="man")]},
        auto={"es": [_track(url="auto")]},
    )
    pick = pick_subtitle(info, {"es": "any"}, prefer_manual=True)
    assert pick is not None
    assert pick.source == "manual"


def test_any_defer_to_prefer_manual_default_false() -> None:
    info = _info(
        manual={"es": [_track(url="man")]},
        auto={"es": [_track(url="auto")]},
    )
    pick = pick_subtitle(info, {"es": "any"}, prefer_manual=False)
    assert pick is not None
    assert pick.source == "auto"


def test_picks_best_format_within_track() -> None:
    info = _info(manual={"en": [_track(ext="ttml", url="t"), _track(ext="json3", url="j")]})
    pick = pick_subtitle(info, {"en": "manual"}, prefer_manual=True)
    assert pick.url == "j"


# ---------- language normalisation ----------

def test_language_base_match() -> None:
    """`es-419` preference matches the `es` caption track."""
    info = _info(manual={"es": [_track(url="u")]})
    pick = pick_subtitle(info, {"es-419": "manual"}, prefer_manual=True)
    assert pick is not None
    assert pick.lang == "es"


# ---------- legacy list input ----------

def test_legacy_list_input_uses_prefer_manual() -> None:
    info = _info(
        manual={"es": [_track(url="m")]},
        auto={"es": [_track(url="a")]},
    )
    pick = pick_subtitle(info, ["es"], prefer_manual=True)
    assert pick.source == "manual"
    pick = pick_subtitle(info, ["es"], prefer_manual=False)
    assert pick.source == "auto"


def test_unknown_mode_falls_back_to_any() -> None:
    info = _info(manual={"es": [_track()]}, auto={"es": [_track()]})
    pick = pick_subtitle(info, {"es": "garbage"}, prefer_manual=True)
    assert pick is not None
    assert pick.source == "manual"


# ---------- parse_languages config helper ----------

def test_parse_languages_dict_pass_through() -> None:
    assert parse_languages({"en": "manual", "es": "auto"}, True) == {
        "en": "manual", "es": "auto",
    }


def test_parse_languages_dict_unknown_mode_to_any() -> None:
    assert parse_languages({"en": "garbage"}, True) == {"en": "any"}


def test_parse_languages_legacy_list_to_manual_by_default() -> None:
    assert parse_languages(["es", "en"], prefer_manual=True) == {
        "es": "manual", "en": "manual",
    }


def test_parse_languages_legacy_list_to_auto_when_prefer_manual_false() -> None:
    assert parse_languages(["es", "en"], prefer_manual=False) == {
        "es": "auto", "en": "auto",
    }


def test_parse_languages_none_returns_empty() -> None:
    assert parse_languages(None, True) == {}


# ---------- Config dataclass default shape ----------

def test_config_languages_defaults_to_dict() -> None:
    cfg = Config()
    assert isinstance(cfg.languages, dict)
    # "any", not "manual": the default must not exclude auto-generated captions.
    assert cfg.languages == {"es": "any", "en": "any"}


def test_config_prefer_manual_defaults_true() -> None:
    cfg = Config()
    assert cfg.prefer_manual is True