DrumGroupFinderComponent.py

# Embedded file name: /Users/versonator/Jenkins/live/output/mac_64_static/Release/python-bundle/MIDI Remote Scripts/Launchpad_Pro/DrumGroupFinderComponent.py
# Compiled at: 2018-04-23 20:27:04
from __future__ import absolute_import, print_function, unicode_literals
from itertools import imap, chain
import Live
from _Framework.Util import find_if
from _Framework.SubjectSlot import Subject, subject_slot_group, subject_slot
from _Framework.ControlSurfaceComponent import ControlSurfaceComponent

class DrumGroupFinderComponent(ControlSurfaceComponent, Subject):
    u"""
    Looks in the hierarchy of devices of a track, looking
    for the first available drum-rack (deep-first), updating as the
    device list changes.
    """
    __subject_events__ = (u'drum_group', )
    _drum_group = None

    def __init__(self, target_track_component, layer=None, is_enabled=True, *a, **k):
        super(DrumGroupFinderComponent, self).__init__(*a, **k)
        self._target_track_component = target_track_component
        self._on_track_changed.subject = self._target_track_component
        self.update()

    @property
    def drum_group(self):
        u"""
        The latest found drum rack.
        """
        return self._drum_group

    @property
    def root(self):
        u"""
        The currently observed track.
        """
        return self._target_track_component.target_track

    @subject_slot_group('devices')
    def _on_devices_changed(self, chain):
        self.update()

    @subject_slot_group('chains')
    def _on_chains_changed(self, chain):
        self.update()

    @subject_slot('target_track')
    def _on_track_changed(self):
        self.update()

    def update(self):
        super(DrumGroupFinderComponent, self).update()
        if self.is_enabled():
            self._update_listeners()
            self._update_drum_group()

    def _update_listeners(self):
        root = self.root
        devices = list(find_instrument_devices(root))
        chains = list(chain([root], *[ d.chains for d in devices ]))
        self._on_chains_changed.replace_subjects(devices)
        self._on_devices_changed.replace_subjects(chains)

    def _update_drum_group(self):
        drum_group = find_drum_group_device(self.root)
        if type(drum_group) != type(self._drum_group) or drum_group != self._drum_group:
            self._drum_group = drum_group
        self.notify_drum_group()


def find_instrument_devices(track_or_chain):
    u"""
    Returns a list with all instrument rack descendants from a track
    or chain.
    """
    instrument = find_if(lambda d: d.type == Live.Device.DeviceType.instrument, track_or_chain.devices)
    if instrument and not instrument.can_have_drum_pads and instrument.can_have_chains:
        return chain([instrument], *imap(find_instrument_devices, instrument.chains))
    return []


def find_drum_group_device(track_or_chain):
    u"""
    Looks up recursively for a drum_group device in the track.
    """
    instrument = find_if(lambda d: d.type == Live.Device.DeviceType.instrument, track_or_chain.devices)
    if instrument:
        if instrument.can_have_drum_pads:
            return instrument
        if instrument.can_have_chains:
            return find_if(bool, imap(find_drum_group_device, instrument.chains))
    return