from mopidy.backend import LibraryProvider
from mopidy.models import Ref

class SmartLibrary(LibraryProvider):
    def __init__(self, backend, config):
        super().__init__(backend)
        self.config = config

    def browse(self, uri):
        if uri == "smart:":
            return [
                Ref.directory(uri="smart:genres", name="Genres"),
                Ref.directory(uri="smart:artists", name="Artists"),
            ]

        if uri == "smart:genres":
            return [
                Ref.directory(uri=f"smart:genre:{g}", name=g.title())
                for g in ["rock", "jazz", "blues"]
            ]

        if uri.startswith("smart:genre:"):
            genre = uri.split(":", 2)[2]
            tracks = self._tracks_for_genre(genre)
            return [
                Ref.track(uri=t.uri, name=t.name)
                for t in tracks
            ]

        return []

    def lookup(self, uri):
        # return full Track models for playback
        if uri.startswith("smart:genre:"):
            genre = uri.split(":", 2)[2]
            return self._tracks_for_genre(genre)

        return []

    def _tracks_for_genre(self, genre):
        # WORKS: Use Mopidy’s global search API
        results = self.backend.actor.root.actor.library.search(
            {"genre": [genre]}
        )
        tracks = []
        for r in results:
            if r.tracks:
                tracks.extend(r.tracks)
        return tracks[:50]   # enforce max