#!/usr/bin/env python3
"""
spotify-playlist-csv.py — dump a Spotify playlist to a CSV sldl can search from.

sldl's own vendored Spotify client still calls Spotify's GET /playlists/{id}/tracks
endpoint, which Spotify removed in its February 2026 API changes (see
https://developer.spotify.com/documentation/web-api/references/changes/february-2026)
in favor of /items. Grandfathered apps still get a pass on /tracks for now, but
apps created after that change get a hard 403 there regardless of auth method --
client-credentials, or a correctly-scoped, correctly-owned OAuth user token, none
of it matters, because the endpoint itself is gone for them. sldl has no separate
code path to fall back to /items, so it can never read a playlist for a new app
no matter what alembic hands it.

Rather than depend on sldl's Spotify client at all, this script reads the
playlist itself (via /items, which alembic's own code already migrated to) and
writes the same Artist,Title,Album,Length CSV format upgrade-mp3-to-flac.sh
already feeds to sldl via --input-type csv. run-playlist.sh runs this first and
then points sldl at the CSV instead of the playlist URL, sidestepping sldl's
Spotify client entirely -- for grandfathered and new apps alike.

Usage:
  spotify-playlist-csv.py <playlist_url> <out_csv>

Credentials are read from env vars SPOTIFY_CLIENT_ID and SPOTIFY_CLIENT_SECRET.
SPOTIFY_REFRESH_TOKEN, if set, mints a user token instead of client-credentials
(required for newly created Spotify apps -- see _spotify_auth.get_token).
"""
import csv
import json
import os
import re
import sys
import urllib.error
import urllib.request

from _spotify_auth import get_token

API = "https://api.spotify.com/v1"


def fetch_playlist(url: str, token: str) -> list[dict]:
    m = re.search(r"playlist[/:]([A-Za-z0-9]+)", url)
    if not m:
        sys.exit(f"Could not parse playlist ID from {url!r}")
    pid = m.group(1)
    tracks = []
    # No `fields` filter: Spotify's February 2026 changes renamed each entry's
    # payload from "track" to "item" for apps on the new behavior (extended
    # quota / grandfathered apps keep "track"), and a fields filter selects by
    # key name -- filtering on track(...) silently returns EMPTY pages on the
    # renamed shape. Fetch unfiltered and parse both key names below.
    next_url = f"{API}/playlists/{pid}/items?limit=100"
    while next_url:
        req = urllib.request.Request(next_url, headers={"Authorization": f"Bearer {token}"})
        try:
            with urllib.request.urlopen(req, timeout=15) as r:
                data = json.loads(r.read())
        except urllib.error.HTTPError as e:
            if e.code in (403, 404):
                sys.exit(
                    f"Spotify returned {e.code} loading this playlist. The connected "
                    "Spotify account can't see it: it must own the playlist, be a "
                    "collaborator on it, or (for grandfathered apps) the playlist "
                    "must be Public. Check which account is connected via "
                    "/connect/spotify."
                )
            raise
        if "items" not in data:
            # New-behavior apps get metadata only (no items field) for
            # playlists the connected account doesn't own or collaborate on.
            sys.exit(
                "Spotify returned this playlist without its contents. For newly "
                "created Spotify apps, the connected account must OWN the playlist "
                "or be a collaborator on it (public is no longer enough). Ask the "
                "owner to make it collaborative and add you, or recreate the "
                "playlist under the connected account."
            )
        for item in data["items"]:
            t = item.get("track") or item.get("item")
            if not t or t.get("is_local"):
                continue
            # All artists, comma-joined -- matches what sldl's own Spotify
            # extractor fed its search, so multi-artist tracks match no worse
            # than they did before the CSV detour.
            artists = [a["name"] for a in (t.get("artists") or []) if a.get("name")]
            tracks.append(
                {
                    "artist": ", ".join(artists),
                    "title": t.get("name", ""),
                    "album": (t.get("album") or {}).get("name", ""),
                    "length": round((t.get("duration_ms") or 0) / 1000),
                }
            )
        next_url = data.get("next")
    return tracks


def main() -> int:
    if len(sys.argv) != 3:
        sys.exit(f"Usage: {sys.argv[0]} <playlist_url> <out_csv>")
    url, out_path = sys.argv[1], sys.argv[2]

    cid = os.environ.get("SPOTIFY_CLIENT_ID")
    csec = os.environ.get("SPOTIFY_CLIENT_SECRET")
    refresh = os.environ.get("SPOTIFY_REFRESH_TOKEN") or None
    if not cid or not csec:
        sys.exit("SPOTIFY_CLIENT_ID and SPOTIFY_CLIENT_SECRET must be set")

    token = get_token(cid, csec, refresh)
    tracks = fetch_playlist(url, token)

    with open(out_path, "w", newline="") as f:
        writer = csv.writer(f)
        writer.writerow(["Artist", "Title", "Album", "Length"])
        for t in tracks:
            writer.writerow([t["artist"], t["title"], t["album"], t["length"]])

    print(f"[spotify-playlist-csv] wrote {len(tracks)} tracks to {out_path}")
    return 0


if __name__ == "__main__":
    sys.exit(main())