from __future__ import annotations

from pathlib import Path
from typing import Any

import pytest
from ruamel.yaml import YAML

#: Half a second of silence, so ``mutagen`` reports a real duration and tags can be
#: written onto a file that is actually an MP3. Generated once with ffmpeg.
SILENCE = Path(__file__).parent / "data" / "silence.mp3"

VALID_CONFIG: dict[str, Any] = {
    "general": {
        "library": {"root": "music", "cache": ".cache"},
        "serial_port": "/dev/ttyUSB0",
        "alsa_device": "simulate",
        "min_volume": 0,
        "max_volume": 60,
        "initial_volume": 40,
    },
    "figures": {
        "fuchs": {"id": "04a1b2c3d4", "colors": ["#ff6600", "#ffcc00", "#331100", "wff"]},
        # One of each, so the figure-kind branch is exercised by every fixture.
        "eule": {
            "id": "04b2c3d4e5",
            "colors": ["#3355ff", "#66aaff", "#001133", "#ffffff"],
            "kind": "book",
        },
    },
}


def write_track(path: Path, **tags: str) -> Path:
    """Copy the silence fixture to ``path`` and stamp the given easy-mode ID3 tags."""
    import mutagen

    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_bytes(SILENCE.read_bytes())
    if tags:
        audio = mutagen.File(path, easy=True)
        if audio.tags is None:
            audio.add_tags()
        for key, value in tags.items():
            audio[key] = value
        audio.save()
    return path


@pytest.fixture
def config_dir(tmp_path: Path) -> Path:
    """A directory holding a small but structurally real music library.

    Two figure folders (matching ``VALID_CONFIG``), one music album, one audiobook and
    one podcast - enough for every branch the scanner has.
    """
    root = tmp_path / "music"

    for figure, tracks in (("fuchs", 3), ("eule", 2)):
        for index in range(tracks):
            write_track(
                root / "Figuren" / figure / f"{index:02d} - track.mp3",
                title=f"Track {index}",
                album="Waldlieder",
                albumartist="Die Tiere",
            )

    for index in range(2):
        write_track(
            root / "Musik" / "Kinderparty - Kinderparty Lieder" / f"{index:02d} - lied.mp3",
            title=f"Lied {index}",
            album="Kinderparty Lieder",
            albumartist="Kinderparty",
        )

    for index in range(2):
        write_track(
            root / "Hörbücher" / "Conni - Conni in den Bergen" / f"{index:02d} - teil.mp3",
            title=f"Teil {index}",
            album="Conni in den Bergen",
            albumartist="Conni, Julia Boehme",
        )

    podcast = root / "Kinderpodcasts" / "Wissen macht Ah"
    for date, title in (("20240101", "Alt"), ("20260101", "Neu")):
        write_track(
            podcast / f"{date} - {title}.mp3",
            title=title,
            album="Wissen macht Ah! - Podcast",
            albumartist="Ein Name, Noch Einer, Und Einer",
        )
    # The two kinds of scratch file a podcast downloader leaves behind.
    (podcast / "archive.json").write_text("[]")
    (podcast / ".podcast-dl-abc.download.tmp").write_bytes(b"")

    return tmp_path


def write_config(directory: Path, data: dict[str, Any], name: str = "config.yml") -> Path:
    path = directory / name
    with path.open("w", encoding="utf-8") as handle:
        YAML(typ="safe").dump(data, handle)
    return path