////////////////////////////////
//~ Decode

MP3_Result MP3_Decode(Arena *arena, String encoded, u32 sample_rate, MP3_DecodeFlag flags)
{
    MP3_Result result = ZI;
    u64 bytes_per_sample = 2;

    u64 channel_count;
    u32 channel_mask;
    if (flags & MP3_DecodeFlag_Stereo)
    {
        channel_count = 2;
        channel_mask = SPEAKER_FRONT_LEFT | SPEAKER_FRONT_RIGHT;
    }
    else
    {
        channel_count = 1;
        channel_mask = SPEAKER_FRONT_CENTER;
    }

    //- Startup

    MFStartup(MF_VERSION, MFSTARTUP_LITE);

    /* Create IStream from encoded string */
    IStream *i_stream = SHCreateMemStream(encoded.text, encoded.len);

    /* Create IMFByteStream from IStream */
    IMFByteStream *byte_stream = 0;
    MFCreateMFByteStreamOnStream(i_stream, &byte_stream);

    /* Create reader from IMFByteStream */
    IMFSourceReader *reader;
    MFCreateSourceReaderFromByteStream(byte_stream, 0, &reader);

    //- Get media type

    /* Read only first audio stream */
    IMFSourceReader_SetStreamSelection(reader, (DWORD)MF_SOURCE_READER_ALL_STREAMS, 0);
    IMFSourceReader_SetStreamSelection(reader, (DWORD)MF_SOURCE_READER_FIRST_AUDIO_STREAM, 1);

    WAVEFORMATEXTENSIBLE format = {
        .Format = {
            .wFormatTag = WAVE_FORMAT_EXTENSIBLE,
            .nChannels = (WORD)channel_count,
            .nSamplesPerSec = (WORD)sample_rate,
            .nAvgBytesPerSec = (DWORD)(sample_rate * channel_count * bytes_per_sample),
            .nBlockAlign = (WORD)(channel_count * bytes_per_sample),
            .wBitsPerSample = (WORD)(8 * bytes_per_sample),
            .cbSize = sizeof(format) - sizeof(format.Format)
        },
        .Samples.wValidBitsPerSample = 8 * bytes_per_sample,
        .dwChannelMask = channel_mask,
        .SubFormat = MEDIASUBTYPE_PCM
    };

    /* Media Foundation in Windows 8+ allows reader to convert output to different format than native */
    IMFMediaType *type;
    MFCreateMediaType(&type);
    MFInitMediaTypeFromWaveFormatEx(type, &format.Format, sizeof(format));
    IMFSourceReader_SetCurrentMediaType(reader, (DWORD)MF_SOURCE_READER_FIRST_AUDIO_STREAM, 0, type);
    IMFMediaType_Release(type);

    //- Read

    result.samples = PushDry(arena, i16);
    u64 sample_bytes_read = 0;
    for (;;)
    {
        IMFSample *sample;
        DWORD sample_flags = 0;
        HRESULT hr = IMFSourceReader_ReadSample(reader, (DWORD)MF_SOURCE_READER_FIRST_AUDIO_STREAM, 0, 0, &sample_flags, 0, &sample);
        if (FAILED(hr))
        {
            break;
        }

        /* Check if done */
        if (sample_flags & MF_SOURCE_READERF_ENDOFSTREAM)
        {
            result.ok = 1;
            break;
        }
        Assert(sample_flags == 0);

        /* Read samples */
        IMFMediaBuffer *buffer;
        IMFSample_ConvertToContiguousBuffer(sample, &buffer);

        BYTE *src;
        DWORD size_bytes;
        IMFMediaBuffer_Lock(buffer, &src, 0, &size_bytes);
        {
            i16 *dst = PushStructsNoZero(arena, i16, (size_bytes + 1) >> 1);
            CopyBytes(dst, src, size_bytes);
            sample_bytes_read += size_bytes;
        }
        IMFMediaBuffer_Unlock(buffer);

        IMediaBuffer_Release(buffer);
        IMFSample_Release(sample);
    }

    result.samples_count = sample_bytes_read / bytes_per_sample;

    //- Cleanup

    IMFSourceReader_Release(reader);
    IMFByteStream_Close(byte_stream);
    /* FIXME: Enable this */
    //IStream_Release(i_stream);
    MFShutdown();

    return result;
}