#include <iostream>

#define COBJMACROS
#include <mmdeviceapi.h>
#include <audioclient.h>

int enumerate_sound_devices()
{
    // Initialize COM-interface subsystem
    CoInitializeEx(NULL, 0);

    IMMDeviceEnumerator *enu;
    const GUID _CLSID_MMDeviceEnumerator = {0xbcde0395, 0xe52f, 0x467c, {0x8e,0x3d, 0xc4,0x57,0x92,0x91,0x69,0x2e}};
    const GUID _IID_IMMDeviceEnumerator = {0xa95664d2, 0x9614, 0x4f35, {0xa7,0x46, 0xde,0x8d,0xb6,0x36,0x17,0xe6}};
    CoCreateInstance(_CLSID_MMDeviceEnumerator, NULL, CLSCTX_ALL, _IID_IMMDeviceEnumerator, (void**)&enu);

    bool playback = true;

    IMMDeviceCollection *dcoll;
    EDataFlow mode = (playback) ? eRender : eCapture;
    enu->EnumAudioEndpoints(mode, DEVICE_STATE_ACTIVE, &dcoll);

    for (int i = 0; ; i++)
    {
        IMMDevice *dev;
        if (0 != dcoll->Item(i, &dev))
            break;

        IPropertyStore *props;
        dev->OpenPropertyStore(STGM_READ, &props);

        PROPVARIANT name;

        PropVariantInit(&name);
        const PROPERTYKEY PKEY_Device_FriendlyName = {{0xa45c254e, 0xdf1c, 0x4efd, {0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0}}, 14};

        props->GetValue(PKEY_Device_FriendlyName, &name);

        const wchar_t *device_name = name.pwszVal;


        wchar_t* device_id = NULL;
        dev->GetId(&device_id);

        IMMDevice *def_dev = NULL;
        enu->GetDefaultAudioEndpoint(mode, eConsole, &def_dev);

        def_dev->Release();

        CoTaskMemFree(device_id);

        PropVariantClear(&name);

        dev->Release();
    }

    //IMMDeviceEnumerator_Release(enu);
    dcoll->Release();
    enu->Release();

    return 0;
}

int open_shared_buffer()
{
    bool playback = true;

    IMMDeviceEnumerator *enu;
    const GUID CLSID_MMDeviceEnumerator = {0xbcde0395, 0xe52f, 0x467c, {0x8e,0x3d, 0xc4,0x57,0x92,0x91,0x69,0x2e}};
    const GUID IID_IMMDeviceEnumerator = {0xa95664d2, 0x9614, 0x4f35, {0xa7,0x46, 0xde,0x8d,0xb6,0x36,0x17,0xe6}};
    CoCreateInstance(CLSID_MMDeviceEnumerator, NULL, CLSCTX_ALL, IID_IMMDeviceEnumerator, (void**)&enu);


    IMMDevice *dev;

    wchar_t* device_id = NULL;
    if (device_id == NULL)
    {
        EDataFlow mode = (playback) ? eRender : eCapture;
        enu->GetDefaultAudioEndpoint(mode, eConsole, &dev);
    } else {
        enu->GetDevice(device_id, &dev);
    }

    IAudioClient* client;
    const GUID IID_IAudioClient = {0x1cb9ad4c, 0xdbfa, 0x4c32, {0xb1,0x78, 0xc2,0xf5,0x68,0xa7,0x03,0xb2}};
    dev->Activate(IID_IAudioClient, CLSCTX_ALL, NULL, (void**)&client);

    WAVEFORMATEX *wf;
    client->GetMixFormat(&wf);

    int buffer_length_msec = 500;
    REFERENCE_TIME dur = buffer_length_msec * 1000 * 10;

    AUDCLNT_SHAREMODE mode = AUDCLNT_SHAREMODE_SHARED;
    int aflags = 0;

    client->Initialize(mode, aflags, dur, dur, wf, NULL);

    u_int buf_frames;

    client->GetBufferSize(&buf_frames);

    buffer_length_msec = buf_frames * 1000 / wf->nSamplesPerSec;

    CoTaskMemFree(wf);
    client->Release();
    dev->Release();
    enu->Release();

    return 0;
}

int record_shared()
{
    bool playback = true;

    IMMDeviceEnumerator *enu;
    const GUID CLSID_MMDeviceEnumerator = {0xbcde0395, 0xe52f, 0x467c, {0x8e,0x3d, 0xc4,0x57,0x92,0x91,0x69,0x2e}};
    const GUID IID_IMMDeviceEnumerator = {0xa95664d2, 0x9614, 0x4f35, {0xa7,0x46, 0xde,0x8d,0xb6,0x36,0x17,0xe6}};
    CoCreateInstance(CLSID_MMDeviceEnumerator, NULL, CLSCTX_ALL, IID_IMMDeviceEnumerator, (void**)&enu);


    IMMDevice *dev;

    wchar_t* device_id = NULL;
    if (device_id == NULL)
    {
        EDataFlow mode = (playback) ? eRender : eCapture;
        enu->GetDefaultAudioEndpoint(mode, eConsole, &dev);
    } else {
        enu->GetDevice(device_id, &dev);
    }

    IAudioClient* client;
    const GUID IID_IAudioClient = {0x1cb9ad4c, 0xdbfa, 0x4c32, {0xb1,0x78, 0xc2,0xf5,0x68,0xa7,0x03,0xb2}};
    dev->Activate(IID_IAudioClient, CLSCTX_ALL, NULL, (void**)&client);

    WAVEFORMATEX *wf;
    client->GetMixFormat(&wf);

    int buffer_length_msec = 500;
    REFERENCE_TIME dur = buffer_length_msec * 1000 * 10;

    AUDCLNT_SHAREMODE mode = AUDCLNT_SHAREMODE_SHARED;
    int aflags = 0;

    client->Initialize(mode, aflags, dur, dur, wf, NULL);

    u_int buf_frames;

    client->GetBufferSize(&buf_frames);

    buffer_length_msec = buf_frames * 1000 / wf->nSamplesPerSec;

    IAudioCaptureClient* capt;
    const GUID IID_IAudioCaptureClient = {0xc8adbd64, 0xe71e, 0x48a0, {0xa4,0xde, 0x18,0x5c,0x39,0x5c,0xd3,0x17}};
    client->GetService(IID_IAudioCaptureClient, (void**)&capt);

    client->Start();

    for (;;)
    {
        u_char * data;
        u_int nframes;
        u_long flags;
        int r = capt->GetBuffer(&data, &nframes, &flags, NULL, NULL);


        if (r == AUDCLNT_S_BUFFER_EMPTY) {
            // Buffer is empty. Wait for more data/
            int period_ms = 100;
            Sleep(period_ms);
            continue;
        } else if (r != 0) {
            // error
        }

        capt->ReleaseBuffer(nframes);
    }

    CoTaskMemFree(wf);
    client->Release();
    dev->Release();
    enu->Release();

    return 0;
}

int play_shared()
{
    bool playback = true;

    IMMDeviceEnumerator *enu;
    const GUID CLSID_MMDeviceEnumerator = {0xbcde0395, 0xe52f, 0x467c, {0x8e,0x3d, 0xc4,0x57,0x92,0x91,0x69,0x2e}};
    const GUID IID_IMMDeviceEnumerator = {0xa95664d2, 0x9614, 0x4f35, {0xa7,0x46, 0xde,0x8d,0xb6,0x36,0x17,0xe6}};
    CoCreateInstance(CLSID_MMDeviceEnumerator, NULL, CLSCTX_ALL, IID_IMMDeviceEnumerator, (void**)&enu);


    IMMDevice *dev;

    wchar_t* device_id = NULL;
    if (device_id == NULL)
    {
        EDataFlow mode = (playback) ? eRender : eCapture;
        enu->GetDefaultAudioEndpoint(mode, eConsole, &dev);
    } else {
        enu->GetDevice(device_id, &dev);
    }

    IAudioClient* client;
    const GUID IID_IAudioClient = {0x1cb9ad4c, 0xdbfa, 0x4c32, {0xb1,0x78, 0xc2,0xf5,0x68,0xa7,0x03,0xb2}};
    dev->Activate(IID_IAudioClient, CLSCTX_ALL, NULL, (void**)&client);

    WAVEFORMATEX *wf;
    client->GetMixFormat(&wf);

    int buffer_length_msec = 500;
    REFERENCE_TIME dur = buffer_length_msec * 1000 * 10;

    AUDCLNT_SHAREMODE mode = AUDCLNT_SHAREMODE_SHARED;
    int aflags = 0;

    client->Initialize(mode, aflags, dur, dur, wf, NULL);

    u_int buf_frames;

    client->GetBufferSize(&buf_frames);

    buffer_length_msec = buf_frames * 1000 / wf->nSamplesPerSec;

    IAudioRenderClient *render;
    const GUID IID_IAudioRenderClient = {0xf294acfc, 0x3146, 0x4483, {0xa7,0xbf, 0xad,0xdc,0xa7,0xc2,0x60,0xe2}};
    client->GetService(IID_IAudioRenderClient, (void**)&render);


    u_int filled;
    client->GetCurrentPadding(&filled);

    int n_free_frames = buf_frames - filled;

    int started = 0;

    if (!started)
    {
        client->Start();
        started = 1;
    }

    u_char *data;
    render->GetBuffer(n_free_frames, &data);

    // Drain the audio buffer
    for (;;)
    {
        u_int filled;
        client->GetCurrentPadding(&filled);
        if (filled == 0)
            break;
    }

    render->ReleaseBuffer(n_free_frames, 0);
    render->Release();
    CoTaskMemFree(wf);
    client->Release();
    dev->Release();
    enu->Release();
    return 0;
}


int main()
{
    enumerate_sound_devices();
    open_shared_buffer();
    play_shared();

    std::cout << "Windows Program" << std::endl;
    return 0;
}