emmental/lib/tag.py

# Copyright 2021 (c) Anna Schumaker.
from . import publisher
import threading

class Tag:
    def __init__(self, name):
        self.name = name
        self.tracks = [ ]
        self.widgets = None
        self.lock = threading.Lock()
        self.TrackAdded = publisher.Publisher()
        self.TrackRemoved = publisher.Publisher()

    def __getstate__(self):
        with self.lock:
            return { "name"   : self.name,
                     "tracks" : [ t.trackid for t in self.tracks ] }

    def __len__(self):
        with self.lock:
            return len(self.tracks)

    def __lt__(self, rhs):
        if not isinstance(rhs, SuperTag):
            return self.name < rhs.name
        if self == rhs.parent:
            return True
        return self.name < rhs.parent.name

    def __setstate__(self, state):
        self.name    = state["name"]
        self.tracks  = state["tracks"]
        self.widgets = None
        self.lock    = threading.Lock()
        self.TrackAdded   = publisher.Publisher()
        self.TrackRemoved = publisher.Publisher()

    def __str__(self):
        return self.name

    def add_track(self, track):
        with self.lock:
            self.tracks.append(track)
        self.TrackAdded.publish(self, track)

    def init_track(self, track):
        with self.lock:
            try:
                i = self.tracks.index(track.trackid)
                self.tracks[i] = track
            except Exception as e:
                pass

    def remove_track(self, track):
        with self.lock:
            self.tracks.remove(track)
        self.TrackRemoved.publish(self, track)


class SuperTag(Tag):
    def __init__(self, parent, name):
        Tag.__init__(self, name)
        self.parent = parent

    def __getstate__(self):
        with self.lock:
            return { "name"   : self.name,
                     "tracks" : [ t.trackid for t in self.tracks ],
                     "parent" : self.parent }

    def __lt__(self, rhs):
        if not isinstance(rhs, SuperTag):
            return self.parent.name < rhs.name
        if self.parent == rhs.parent:
            return self.name < rhs.name
        return self.parent.name < rhs.parent.name

    def __setstate__(self, state):
        Tag.__setstate__(self, state)
        self.parent = state["parent"]