"""Tests for external subtitle sidecars (src.core.subtitles)."""
import pytest

from src.core.subtitles import (
    SubtitleFile,
    attach_subtitle,
    find_subtitles,
    rename_subtitles_with,
    subtitle_filename,
)


def _video(tmp_path, name="Matrix (1999) [tmdbid-603].mkv"):
    v = tmp_path / name
    v.write_bytes(b"x")
    return v


class TestSubtitleFilename:
    def test_bare_no_language(self):
        assert subtitle_filename("Matrix (1999)", ".srt") == "Matrix (1999).srt"

    def test_with_language(self):
        assert subtitle_filename("Matrix (1999)", ".srt", "cs") == "Matrix (1999).cs.srt"

    def test_with_language_and_flag(self):
        assert subtitle_filename("Matrix (1999)", ".srt", "cs", "forced") == \
            "Matrix (1999).cs.forced.srt"

    def test_uppercase_input_is_lowered(self):
        assert subtitle_filename("Matrix (1999)", ".SRT", "CS", "FORCED") == \
            "Matrix (1999).cs.forced.srt"


class TestFindSubtitles:
    def test_finds_bare_language_and_flagged(self, tmp_path):
        video = _video(tmp_path)
        (tmp_path / "Matrix (1999) [tmdbid-603].srt").write_bytes(b"x")
        (tmp_path / "Matrix (1999) [tmdbid-603].cs.srt").write_bytes(b"x")
        (tmp_path / "Matrix (1999) [tmdbid-603].en.forced.srt").write_bytes(b"x")

        found = {s.path.name: s for s in find_subtitles(video)}
        assert set(found) == {
            "Matrix (1999) [tmdbid-603].srt",
            "Matrix (1999) [tmdbid-603].cs.srt",
            "Matrix (1999) [tmdbid-603].en.forced.srt",
        }
        assert found["Matrix (1999) [tmdbid-603].srt"].language is None
        assert found["Matrix (1999) [tmdbid-603].cs.srt"].language == "cs"
        assert found["Matrix (1999) [tmdbid-603].en.forced.srt"].language == "en"
        assert found["Matrix (1999) [tmdbid-603].en.forced.srt"].flag == "forced"

    def test_ignores_unrelated_and_overlapping_stem(self, tmp_path):
        video = _video(tmp_path, "Matrix.mkv")
        (tmp_path / "Matrix Reloaded.srt").write_bytes(b"x")  # overlapping prefix
        (tmp_path / "Matrix.nfo").write_bytes(b"x")           # not a subtitle ext
        (tmp_path / "poster.jpg").write_bytes(b"x")
        assert find_subtitles(video) == []

    def test_ignores_other_movies_subtitle(self, tmp_path):
        video = _video(tmp_path, "Matrix.mkv")
        (tmp_path / "Other Movie.cs.srt").write_bytes(b"x")
        assert find_subtitles(video) == []

    def test_missing_folder_is_empty(self, tmp_path):
        assert find_subtitles(tmp_path / "nope" / "video.mkv") == []

    def test_label_property(self):
        assert SubtitleFile(path=None, language="cs").label == "cs"
        assert SubtitleFile(path=None, language="cs", flag="forced").label == "cs (forced)"
        assert SubtitleFile(path=None).label == "?"


class TestAttachSubtitle:
    def test_copies_and_names_to_match_video(self, tmp_path):
        video = _video(tmp_path)
        source = tmp_path / "downloaded.srt"
        source.write_bytes(b"subtitle content")

        target = attach_subtitle(video, source, language="cs")

        assert target == tmp_path / "Matrix (1999) [tmdbid-603].cs.srt"
        assert target.read_bytes() == b"subtitle content"
        assert source.exists()  # copy, not move

    def test_move_removes_source(self, tmp_path):
        video = _video(tmp_path)
        source = tmp_path / "downloaded.srt"
        source.write_bytes(b"x")

        target = attach_subtitle(video, source, language="en", move=True)

        assert target.exists()
        assert not source.exists()

    def test_overwrites_same_language_slot(self, tmp_path):
        video = _video(tmp_path)
        old = tmp_path / "Matrix (1999) [tmdbid-603].cs.srt"
        old.write_bytes(b"old")
        source = tmp_path / "new.srt"
        source.write_bytes(b"new")

        target = attach_subtitle(video, source, language="cs")

        assert target == old
        assert target.read_bytes() == b"new"

    def test_rejects_unsupported_extension(self, tmp_path):
        video = _video(tmp_path)
        source = tmp_path / "notes.txt"
        source.write_bytes(b"x")
        with pytest.raises(ValueError):
            attach_subtitle(video, source)


class TestRenameSubtitlesWith:
    def test_moves_every_sidecar_preserving_lang_and_flag(self, tmp_path):
        old_video = _video(tmp_path, "Matrix.mkv")
        (tmp_path / "Matrix.srt").write_bytes(b"x")
        (tmp_path / "Matrix.cs.srt").write_bytes(b"x")
        (tmp_path / "Matrix.en.forced.srt").write_bytes(b"x")
        new_video = tmp_path / "Matrix (1999) [tmdbid-603].mkv"

        moved = rename_subtitles_with(old_video, new_video)

        names = {p.name for p in moved}
        assert names == {
            "Matrix (1999) [tmdbid-603].srt",
            "Matrix (1999) [tmdbid-603].cs.srt",
            "Matrix (1999) [tmdbid-603].en.forced.srt",
        }
        for name in names:
            assert (tmp_path / name).exists()
        assert not (tmp_path / "Matrix.srt").exists()

    def test_moves_across_folders(self, tmp_path):
        old_dir = tmp_path / "Filmy"
        old_dir.mkdir()
        old_video = old_dir / "Matrix.mkv"
        old_video.write_bytes(b"x")
        (old_dir / "Matrix.cs.srt").write_bytes(b"x")
        new_dir = tmp_path / "Kids"
        new_dir.mkdir()
        new_video = new_dir / "Matrix (1999).mkv"

        moved = rename_subtitles_with(old_video, new_video)

        assert moved == [new_dir / "Matrix (1999).cs.srt"]
        assert (new_dir / "Matrix (1999).cs.srt").exists()
        assert not (old_dir / "Matrix.cs.srt").exists()

    def test_noop_when_path_unchanged(self, tmp_path):
        video = _video(tmp_path, "Matrix.mkv")
        (tmp_path / "Matrix.cs.srt").write_bytes(b"x")
        assert rename_subtitles_with(video, video) == []
        assert (tmp_path / "Matrix.cs.srt").exists()

    def test_no_subtitles_is_noop(self, tmp_path):
        old_video = _video(tmp_path, "Matrix.mkv")
        new_video = tmp_path / "Matrix (1999).mkv"
        assert rename_subtitles_with(old_video, new_video) == []