import logging
from gi.repository import Gst

from lib.config import Config
from lib.tcpmulticonnection import TCPMultiConnection
from lib.clock import Clock


class AVPreviewOutput(TCPMultiConnection):

    def __init__(self, channel, port):
        self.log = logging.getLogger('AVPreviewOutput[{}]'.format(channel))
        super().__init__(port)

        self.channel = channel

        if Config.has_option('previews', 'videocaps'):
            vcaps_out = Config.get('previews', 'videocaps')
        else:
            vcaps_out = Config.get('mix', 'videocaps')

        deinterlace = ""
        if Config.getboolean('previews', 'deinterlace'):
            deinterlace = "deinterlace mode=interlaced !"

        pipeline = """
            intervideosrc channel=video_{channel} !
            {vcaps_in} !
            {deinterlace}
            videoscale !
            videorate !
            {vcaps_out} !
            jpegenc quality=90 !
            queue !
            mux.

            interaudiosrc channel=audio_{channel} !
            {acaps} !
            queue !
            mux.

            matroskamux
                name=mux
                streamable=true
                writing-app=Voctomix-AVPreviewOutput !

            multifdsink
                blocksize=1048576
                buffers-max=500
                sync-method=next-keyframe
                name=fd
        """.format(
            channel=self.channel,
            acaps=Config.get('mix', 'audiocaps'),
            vcaps_in=Config.get('mix', 'videocaps'),
            vcaps_out=vcaps_out,
            deinterlace=deinterlace
        )

        self.log.debug('Creating Output-Pipeline:\n%s', pipeline)
        self.outputPipeline = Gst.parse_launch(pipeline)
        self.outputPipeline.use_clock(Clock)

        self.log.debug('Binding Error & End-of-Stream-Signal '
                       'on Output-Pipeline')
        self.outputPipeline.bus.add_signal_watch()
        self.outputPipeline.bus.connect("message::eos", self.on_eos)
        self.outputPipeline.bus.connect("message::error", self.on_error)

        self.log.debug('Launching Output-Pipeline')
        self.outputPipeline.set_state(Gst.State.PLAYING)

    def on_accepted(self, conn, addr):
        self.log.debug('Adding fd %u to multifdsink', conn.fileno())
        fdsink = self.outputPipeline.get_by_name('fd')
        fdsink.emit('add', conn.fileno())

        def on_disconnect(multifdsink, fileno):
            if fileno == conn.fileno():
                self.log.debug('fd %u removed from multifdsink', fileno)
                self.close_connection(conn)

        fdsink.connect('client-fd-removed', on_disconnect)

    def on_eos(self, bus, message):
        self.log.debug('Received End-of-Stream-Signal on Output-Pipeline')

    def on_error(self, bus, message):
        self.log.debug('Received Error-Signal on Output-Pipeline')
        (error, debug) = message.parse_error()
        self.log.debug('Error-Details: #%u: %s', error.code, debug)