# Python imports

# Lib imports
import gi
gi.require_version('Gtk', '3.0')
from gi.repository import Gtk

# Application imports
from ..widgets.audio_sink import AudioSink


class SinkInputList(Gtk.ScrolledWindow):
    def __init__(self, pulse):
        super(SinkInputList, self).__init__()

        self.pulse    = pulse
        self._vadjust = None
        self._box     = None

        self._setup_styling()
        self._setup_signals()
        self._subscribe_to_events()
        self._load_widgets()

        self.show_all()


    def _setup_styling(self):
        ctx = self.get_style_context()
        ctx.add_class("sink-list-container")
        self.set_vexpand(True)
        self.set_overlay_scrolling(False)

    def _setup_signals(self):
        ...

    def _subscribe_to_events(self):
        event_system.subscribe("handle_new_sync_input", self._handle_new_sync_input)
        event_system.subscribe("handle_del_sync_input", self._handle_del_sync_input)
        event_system.subscribe("handle_cng_sync_input", self._handle_cng_sync_input)

    def _load_widgets(self):
        viewport      = Gtk.Viewport()
        box           = Gtk.Box()
        self._box     = box
        self._vadjust = self.get_vadjustment()

        box.set_orientation(Gtk.Orientation.VERTICAL)

        viewport.add(box)
        self.add(viewport)

    def _handle_cng_sync_input(self, index):
        for child in self._box.get_children():
            if index == child.sink.index:
                child.do_update()
                # If sink out of view in list just scroll fully down.
                # Most cases will scroll b/c most recently added sink volume changed elsewhere.
                # (Edge case is we update the volume of a sink in between and overshoot.)
                # I don't personally care and this isn't a pain point for me.
                if not child.get_mapped():
                    self._scroll_to_bottom(self._vadjust)

    def _handle_new_sync_input(self, index):
        sink_input = self.pulse.sink_input_list()[-1]
        self._box.add( AudioSink(self.pulse, sink_input) )
        self._scroll_to_bottom(self._vadjust)

    def _handle_del_sync_input(self, index):
        parent = self.get_parent()
        for sink_input in parent.sink_inputs:
            if index == sink_input.index:
                parent.sink_inputs.remove(sink_input)

        for child in self._box.get_children():
            if index == child.sink.index:
                child.destroy()
                self._scroll_to_bottom(self._vadjust)

    def _scroll_to_bottom(self, adjustment):
        self._vadjust.set_value( adjustment.get_upper() )

    def get_box(self):
        return self._box