alembic/app/services/playlist_service.py

import json
import subprocess
import time

from sqlalchemy import select
from sqlalchemy.orm import Session

from app.models import Playlist
from app.settings import settings

# The 17-entry array this project is migrating off of (was hardcoded in
# /opt/sldl/configs/regen.sh). Used once by seed_legacy() during Stage 1/2
# of the migration; the DB is the source of truth from then on.
LEGACY_PLAYLISTS = {
    "techno": "https://open.spotify.com/playlist/5GlAkczmLWJFIJO4FvkLEZ",
    "house": "https://open.spotify.com/playlist/2XF8ye6O5xqzT4NSfIXdfJ",
    "lofi": "https://open.spotify.com/playlist/0qnyF6TAmuT3U6hFH2fiF1",
    "y2k": "https://open.spotify.com/playlist/0iaA7ZJS00aRxhMwZn2GCU",
    "weeb": "https://open.spotify.com/playlist/0599AbpsKRjsp2rlJI8jhf",
    "shoegaze": "https://open.spotify.com/playlist/3R4S3tmbVKjXQ1RPAmryC5",
    "bass": "https://open.spotify.com/playlist/2zkF4S16efaMmmzdIOe5w2",
    "hiphop": "https://open.spotify.com/playlist/42JxTtOLJ7gG1ybfyy7Vmi",
    "modular": "https://open.spotify.com/playlist/2kOfP2EM8dzdMYC6fXvlLb",
    "hotdog": "https://open.spotify.com/playlist/53HrOL0qw47G9ywYZz3kgX",
    "kpop": "https://open.spotify.com/playlist/31e2V512TIqr5JIfgkyseo",
    "jungle": "https://open.spotify.com/playlist/4LjLeXg6ElneQiTaIcAHhE",
    "goldenera": "https://open.spotify.com/playlist/57vArhigysJfgwB6CY4VXR",
    "botanica": "https://open.spotify.com/playlist/5KgQT9YWz3EqhIN4Jh69IU",
    "digicore": "https://open.spotify.com/playlist/6tWHtPBECZTkZHPKFA3Fq4",
    "hardcore": "https://open.spotify.com/playlist/1J1lbzlQKligzr2LWaq9Ex",
    "liked": "https://open.spotify.com/playlist/4Z3qCYuU1sjNeNYO3Amzeo",
}


def list_all(db: Session) -> list[Playlist]:
    return list(db.execute(select(Playlist).order_by(Playlist.name)).scalars())


def get(db: Session, playlist_id: int) -> Playlist | None:
    return db.get(Playlist, playlist_id)


def get_by_name(db: Session, name: str) -> Playlist | None:
    return db.execute(select(Playlist).where(Playlist.name == name)).scalar_one_or_none()


def create(
    db: Session,
    name: str,
    spotify_url: str,
    active: bool = True,
    no_m3u: bool = False,
    notes: str | None = None,
) -> Playlist:
    now = time.time()
    playlist = Playlist(
        name=name,
        spotify_url=spotify_url,
        active=active,
        no_m3u=no_m3u,
        notes=notes,
        created_at=now,
        updated_at=now,
    )
    db.add(playlist)
    db.commit()
    db.refresh(playlist)
    _sync_to_disk(db)
    return playlist


def update(db: Session, playlist_id: int, **fields) -> Playlist:
    playlist = db.get(Playlist, playlist_id)
    if playlist is None:
        raise ValueError(f"no playlist with id={playlist_id}")
    for key, value in fields.items():
        setattr(playlist, key, value)
    playlist.updated_at = time.time()
    db.commit()
    db.refresh(playlist)
    _sync_to_disk(db)
    return playlist


def delete(db: Session, playlist_id: int) -> None:
    """Remove the playlist from the DB and delete its rendered .conf file.
    Does NOT touch anything already downloaded/imported for it — that's a
    library decision, not a playlist-definition one."""
    playlist = db.get(Playlist, playlist_id)
    if playlist is None:
        return
    name = playlist.name
    db.delete(playlist)
    db.commit()
    conf_path = settings.pipeline_config_dir / f"{name}.conf"
    conf_path.unlink(missing_ok=True)
    _write_playlists_json(db)


def seed_legacy(db: Session) -> int:
    """One-time import of the legacy hardcoded array (migration Stage 1/2).
    Skips any name that already exists. Returns the number of rows created."""
    created = 0
    for name, url in LEGACY_PLAYLISTS.items():
        if get_by_name(db, name) is not None:
            continue
        no_m3u = name == "liked"  # matches --no-m3u liked in the old crontab
        create(db, name=name, spotify_url=url, no_m3u=no_m3u)
        created += 1
    return created


def _write_playlists_json(db: Session) -> None:
    """The file regen.sh reads. Every active-or-not playlist is included
    (see regen.sh's header comment) so a manual run is always possible;
    the scheduler is what actually skips inactive ones."""
    playlists = list_all(db)
    payload = [
        {
            "name": p.name,
            "spotify_url": p.spotify_url,
            "active": p.active,
            "no_m3u": p.no_m3u,
        }
        for p in playlists
    ]
    settings.pipeline_config_dir.mkdir(parents=True, exist_ok=True)
    out_path = settings.pipeline_config_dir / "playlists.json"
    out_path.write_text(json.dumps(payload, indent=2))


def regenerate_confs(db: Session) -> subprocess.CompletedProcess:
    """Write playlists.json, then run regen.sh to render/refresh every
    playlist's .conf file. Newly-created .conf files still have unpatched
    SOULSEEK_USER/SOULSEEK_PASS/SPOTIFY_CLIENT_ID/SPOTIFY_CLIENT_SECRET
    placeholders at this point — the caller (routers/playlists.py) is
    responsible for re-rendering credentials afterward via
    credential_service.render_scope(db, "soulseek"/"spotify")."""
    _write_playlists_json(db)
    regen_script = settings.pipeline_dir / "configs" / "regen.sh"
    return subprocess.run(
        [str(regen_script)],
        capture_output=True,
        text=True,
        env={
            "ALEMBIC_CONFIG_DIR": str(settings.alembic_config_dir),
            "MUSIC_DATA_DIR": str(settings.music_data_dir),
            "PIPELINE_DIR": str(settings.pipeline_dir),
            "PATH": "/usr/bin:/bin",
        },
    )


def _sync_to_disk(db: Session) -> None:
    """Convenience wrapper used by create()/update(): regenerate confs and
    immediately re-patch credentials into any newly-rendered file."""
    regenerate_confs(db)
    # Imported lazily to avoid a circular import (credential_service doesn't
    # depend on playlist_service, but importing at module load time would
    # still work here — done lazily anyway to keep the dependency direction
    # obvious as both services grow).
    from app.services import credential_service

    credential_service.render_scope(db, "soulseek")
    credential_service.render_scope(db, "spotify")