# Copyright 2021 (c) Anna Schumaker.
import db
import datetime
from gi.repository import GObject
from . import metadata

class Task(GObject.GObject):
    def run_task(self): raise NotImplementedError


class CommitTask(Task):
    def run_task(self):
        db.sql.commit()
        db.sql.optimize()


class FileTask(Task):
    def __init__(self, library, filepath):
        Task.__init__(self)
        self.library  = library
        self.filepath = filepath

    def run_task(self):
        if db.track.Table.lookup(self.filepath):
            return

        with metadata.Metadata(self.filepath) as meta:
            artist = db.artist.Table.find(meta.artist(), meta.artistsort())
            album  = artist.find_album(meta.album(), meta.release())
            disc   = album.find_disc(meta.discnumber(), meta.discsubtitle())
            decade = db.decade.Table.find(meta.decade())
            year   = decade.find_year(meta.year())
            track  = db.track.Table.insert(self.library, artist, album, disc,
                                           decade, year, meta.tracknumber(),
                                           meta.length(), meta.title(),
                                           self.filepath)
            for genre in meta.genres():
                db.genre.Table.find(genre).add_track(track)


class DirectoryTask(Task):
    def __init__(self, library, dirpath):
        Task.__init__(self)
        self.library = library
        self.dirpath = dirpath

    def run_task(self):
        res = [ ]
        for f in self.dirpath.iterdir():
            if f.is_file():
                res.append(FileTask(self.library, f))
            elif f.is_dir():
                res.append(DirectoryTask(self.library, f))
        res.append(CommitTask())
        return res


class CheckTask(Task):
    def __init__(self, tracks):
        Task.__init__(self)
        self.tracks = tracks

    def run_task(self):
        need_commit = False
        for track in self.tracks:
            if not track.path.exists():
                db.track.Table.delete(track)
                need_commit = True
        if need_commit:
            db.sql.commit()


class CheckSchedulerTask(Task):
    def __init__(self, library):
        Task.__init__(self)
        self.library = library

    def track_chunks(self):
        tracks = self.library.tracks()
        while len(tracks) > 0:
            res = tracks[:50]
            tracks = tracks[50:]
            yield res

    def run_task(self):
        return [ CheckTask(tracks) for tracks in self.track_chunks() ]


class RemoveTask(Task):
    def __init__(self, tracks):
        Task.__init__(self)
        self.tracks = tracks

    def run_task(self):
        for track in self.tracks:
            db.track.Table.delete(track)
        db.sql.commit()


class RemoveLibraryTask(Task):
    def __init__(self, library):
        Task.__init__(self)
        self.library = library

    def run_task(self):
        db.library.Table.delete(self.library)
        db.sql.commit()


class RemoveLibrarySchedulerTask(Task):
    def __init__(self, library):
        Task.__init__(self)
        self.library = library

    def track_chunks(self):
        tracks = self.library.tracks()
        while len(tracks) > 0:
            res = tracks[:50]
            tracks = tracks[50:]
            yield res

    def run_task(self):
        return [ RemoveTask(tracks) for tracks in self.track_chunks() ] + \
               [ RemoveLibraryTask(self.library) ]


class EnableLibraryTask(Task):
    def __init__(self, library, enable):
        Task.__init__(self)
        self.library = library
        self.enable = enable

    def run_task(self):
        self.library.set_property("enabled", self.enable)