import av
from av.filter import Graph


def main():
    input_container = av.open('supernatural.webm', mode='r')
    input_container2 = av.open('yiv3.webm', mode='r')
    input_video_stream = input_container.streams.video[0]

    output_container = av.open("out.mp4", "w")
    output_audio_stream = output_container.add_stream('aac', rate=input_container2.streams.audio[0].base_rate)

    graph = Graph()

    in_src = graph.add_abuffer(template=input_container.streams.audio[0])
    in_src2 = graph.add_abuffer(template=input_container2.streams.audio[0])
    pad = graph.add("amix", "inputs=2:duration=longest")
    print(dir(pad))
    in_src.link_to(pad, 0, 0)
    in_src2.link_to(pad, 0, 1)
    sink = graph.add('abuffersink')
    pad.link_to(sink)
    graph.configure()

    for frame in input_container.decode(audio=0):
        in_src.push(frame)

    for frame in input_container2.decode(audio=0):
        in_src2.push(frame)
    while True:
        try:
            filtered_frame = pad.pull()
            output_container.mux(output_audio_stream.encode(filtered_frame))
        except:
            break

    for packet in output_audio_stream.encode():
        output_container.mux(packet)

    input_container.close()
    input_container2.close()
    output_container.close()


if __name__ == '__main__':
    main()