from unittest.mock import patch
import warnings
import tarfile

import torch
from torchaudio.backend import _soundfile_backend as soundfile_backend
from torchaudio._internal import module_utils as _mod_utils

from torchaudio_unittest.common_utils import (
    TempDirMixin,
    PytorchTestCase,
    skipIfNoModule,
    get_wav_data,
    save_wav,
)
from torchaudio_unittest.backend.common import (
    get_bits_per_sample,
    get_encoding,
)
from .common import skipIfFormatNotSupported, parameterize

if _mod_utils.is_module_available("soundfile"):
    import soundfile


@skipIfNoModule("soundfile")
class TestInfo(TempDirMixin, PytorchTestCase):
    @parameterize(
        ["float32", "int32", "int16", "uint8"], [8000, 16000], [1, 2],
    )
    def test_wav(self, dtype, sample_rate, num_channels):
        """`soundfile_backend.info` can check wav file correctly"""
        duration = 1
        path = self.get_temp_path("data.wav")
        data = get_wav_data(
            dtype, num_channels, normalize=False, num_frames=duration * sample_rate
        )
        save_wav(path, data, sample_rate)
        info = soundfile_backend.info(path)
        assert info.sample_rate == sample_rate
        assert info.num_frames == sample_rate * duration
        assert info.num_channels == num_channels
        assert info.bits_per_sample == get_bits_per_sample("wav", dtype)
        assert info.encoding == get_encoding("wav", dtype)

    @parameterize([8000, 16000], [1, 2])
    @skipIfFormatNotSupported("FLAC")
    def test_flac(self, sample_rate, num_channels):
        """`soundfile_backend.info` can check flac file correctly"""
        duration = 1
        num_frames = sample_rate * duration
        data = torch.randn(num_frames, num_channels).numpy()
        path = self.get_temp_path("data.flac")
        soundfile.write(path, data, sample_rate)

        info = soundfile_backend.info(path)
        assert info.sample_rate == sample_rate
        assert info.num_frames == num_frames
        assert info.num_channels == num_channels
        assert info.bits_per_sample == 16
        assert info.encoding == "FLAC"

    @parameterize([8000, 16000], [1, 2])
    @skipIfFormatNotSupported("OGG")
    def test_ogg(self, sample_rate, num_channels):
        """`soundfile_backend.info` can check ogg file correctly"""
        duration = 1
        num_frames = sample_rate * duration
        data = torch.randn(num_frames, num_channels).numpy()
        path = self.get_temp_path("data.ogg")
        soundfile.write(path, data, sample_rate)

        info = soundfile_backend.info(path)
        assert info.sample_rate == sample_rate
        assert info.num_frames == sample_rate * duration
        assert info.num_channels == num_channels
        assert info.bits_per_sample == 0
        assert info.encoding == "VORBIS"

    @parameterize([8000, 16000], [1, 2], [('PCM_24', 24), ('PCM_32', 32)])
    @skipIfFormatNotSupported("NIST")
    def test_sphere(self, sample_rate, num_channels, subtype_and_bit_depth):
        """`soundfile_backend.info` can check sph file correctly"""
        duration = 1
        num_frames = sample_rate * duration
        data = torch.randn(num_frames, num_channels).numpy()
        path = self.get_temp_path("data.nist")
        subtype, bits_per_sample = subtype_and_bit_depth
        soundfile.write(path, data, sample_rate, subtype=subtype)

        info = soundfile_backend.info(path)
        assert info.sample_rate == sample_rate
        assert info.num_frames == sample_rate * duration
        assert info.num_channels == num_channels
        assert info.bits_per_sample == bits_per_sample
        assert info.encoding == "PCM_S"

    def test_unknown_subtype_warning(self):
        """soundfile_backend.info issues a warning when the subtype is unknown

        This will happen if a new subtype is supported in SoundFile: the _SUBTYPE_TO_BITS_PER_SAMPLE
        dict should be updated.
        """
        def _mock_info_func(_):
            class MockSoundFileInfo:
                samplerate = 8000
                frames = 356
                channels = 2
                subtype = 'UNSEEN_SUBTYPE'
                format = 'UNKNOWN'
            return MockSoundFileInfo()

        with patch("soundfile.info", _mock_info_func):
            with warnings.catch_warnings(record=True) as w:
                info = soundfile_backend.info("foo")
                assert len(w) == 1
                assert "UNSEEN_SUBTYPE subtype is unknown to TorchAudio" in str(w[-1].message)
                assert info.bits_per_sample == 0


@skipIfNoModule("soundfile")
class TestFileObject(TempDirMixin, PytorchTestCase):
    def _test_fileobj(self, ext, subtype, bits_per_sample):
        """Query audio via file-like object works"""
        duration = 2
        sample_rate = 16000
        num_channels = 2
        num_frames = sample_rate * duration
        path = self.get_temp_path(f'test.{ext}')

        data = torch.randn(num_frames, num_channels).numpy()
        soundfile.write(path, data, sample_rate, subtype=subtype)

        with open(path, 'rb') as fileobj:
            info = soundfile_backend.info(fileobj)
        assert info.sample_rate == sample_rate
        assert info.num_frames == num_frames
        assert info.num_channels == num_channels
        assert info.bits_per_sample == bits_per_sample
        assert info.encoding == "FLAC" if ext == 'flac' else "PCM_S"

    def test_fileobj_wav(self):
        """Loading audio via file-like object works"""
        self._test_fileobj('wav', 'PCM_16', 16)

    @skipIfFormatNotSupported("FLAC")
    def test_fileobj_flac(self):
        """Loading audio via file-like object works"""
        self._test_fileobj('flac', 'PCM_16', 16)

    def _test_tarobj(self, ext, subtype, bits_per_sample):
        """Query compressed audio via file-like object works"""
        duration = 2
        sample_rate = 16000
        num_channels = 2
        num_frames = sample_rate * duration
        audio_file = f'test.{ext}'
        audio_path = self.get_temp_path(audio_file)
        archive_path = self.get_temp_path('archive.tar.gz')

        data = torch.randn(num_frames, num_channels).numpy()
        soundfile.write(audio_path, data, sample_rate, subtype=subtype)

        with tarfile.TarFile(archive_path, 'w') as tarobj:
            tarobj.add(audio_path, arcname=audio_file)
        with tarfile.TarFile(archive_path, 'r') as tarobj:
            fileobj = tarobj.extractfile(audio_file)
            info = soundfile_backend.info(fileobj)
        assert info.sample_rate == sample_rate
        assert info.num_frames == num_frames
        assert info.num_channels == num_channels
        assert info.bits_per_sample == bits_per_sample
        assert info.encoding == "FLAC" if ext == 'flac' else "PCM_S"

    def test_tarobj_wav(self):
        """Query compressed audio via file-like object works"""
        self._test_tarobj('wav', 'PCM_16', 16)

    @skipIfFormatNotSupported("FLAC")
    def test_tarobj_flac(self):
        """Query compressed audio via file-like object works"""
        self._test_tarobj('flac', 'PCM_16', 16)
