import time

import sounddevice
import sounddevice as sd
from pprint import pformat

DEFAULT = 0
sd.default.channels = 2
sd.default.dtype = "int16"
sd.default.latency = "low"
sd.default.samplerate = 48000

class PCMStream:
    globals()

    def __init__(self, _device_id):
        self.stream = sd.RawInputStream(device=_device_id)

    def change_device(self, _device_id):
        self.clean_up()

        self.stream = sd.RawInputStream(device=_device_id)

    # Stops and destroys the current stream
    def clean_up(self):
        if not self.stream.closed:
            self.stream.stop(ignore_errors=True)
            self.stream.close(ignore_errors=True)

    # Stops the current running stream but does not destroy it
    async def pause(self):
        if self.stream.active:
            self.stream.stop(ignore_errors=True)

    # Plays the stream
    async def play(self):
        if not self.stream.active:
            self.stream.start()

    # call back read function for the stream
    def read(self, num_bytes):
        if self.stream.active:
            # frame is 4 bytes
            frames = int(num_bytes / 4)
            data = self.stream.read(frames)[0]

            # convert to pcm format
            return bytes(data)


class DeviceNotFoundError(Exception):
    def __init__(self):
        self.devices = sd.query_devices()
        self.host_apis = sd.query_hostapis()
        super().__init__("No Devices Found")

    def __str__(self):
        return (
            f"Devices \n"
            f"{self.devices} \n "
            f"Host APIs \n"
            f"{pformat(self.host_apis)}"
        )


def query_devices():
    options = {
        device.get("name"): index
        for index, device in enumerate(sd.query_devices())
        if (device.get("max_input_channels") > 0 and device.get("hostapi") == DEFAULT)
    }

    if not options:
        raise DeviceNotFoundError()

    return options