#include "config.h"

#include "base.h"

#include <algorithm>
#include <array>
#include <atomic>

#ifdef _WIN32
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <mmreg.h>

#include "albit.h"
#include "core/logging.h"
#include "aloptional.h"
#endif

#include "atomic.h"
#include "core/devformat.h"


bool BackendBase::reset()
{ throw al::backend_exception{al::backend_error::DeviceError, "Invalid BackendBase call"}; }

void BackendBase::captureSamples(al::byte*, uint)
{ }

uint BackendBase::availableSamples()
{ return 0; }

ClockLatency BackendBase::getClockLatency()
{
    ClockLatency ret;

    uint refcount;
    do {
        refcount = mDevice->waitForMix();
        ret.ClockTime = GetDeviceClockTime(mDevice);
        std::atomic_thread_fence(std::memory_order_acquire);
    } while(refcount != ReadRef(mDevice->MixCount));

    /* NOTE: The device will generally have about all but one periods filled at
     * any given time during playback. Without a more accurate measurement from
     * the output, this is an okay approximation.
     */
    ret.Latency = std::max(std::chrono::seconds{mDevice->BufferSize-mDevice->UpdateSize},
        std::chrono::seconds::zero());
    ret.Latency /= mDevice->Frequency;

    return ret;
}

void BackendBase::setDefaultWFXChannelOrder()
{
    mDevice->RealOut.ChannelIndex.fill(INVALID_CHANNEL_INDEX);

    switch(mDevice->FmtChans)
    {
    case DevFmtMono:
        mDevice->RealOut.ChannelIndex[FrontCenter] = 0;
        break;
    case DevFmtStereo:
        mDevice->RealOut.ChannelIndex[FrontLeft]  = 0;
        mDevice->RealOut.ChannelIndex[FrontRight] = 1;
        break;
    case DevFmtQuad:
        mDevice->RealOut.ChannelIndex[FrontLeft]  = 0;
        mDevice->RealOut.ChannelIndex[FrontRight] = 1;
        mDevice->RealOut.ChannelIndex[BackLeft]   = 2;
        mDevice->RealOut.ChannelIndex[BackRight]  = 3;
        break;
    case DevFmtX51:
        mDevice->RealOut.ChannelIndex[FrontLeft]   = 0;
        mDevice->RealOut.ChannelIndex[FrontRight]  = 1;
        mDevice->RealOut.ChannelIndex[FrontCenter] = 2;
        mDevice->RealOut.ChannelIndex[LFE]         = 3;
        mDevice->RealOut.ChannelIndex[SideLeft]    = 4;
        mDevice->RealOut.ChannelIndex[SideRight]   = 5;
        break;
    case DevFmtX61:
        mDevice->RealOut.ChannelIndex[FrontLeft]   = 0;
        mDevice->RealOut.ChannelIndex[FrontRight]  = 1;
        mDevice->RealOut.ChannelIndex[FrontCenter] = 2;
        mDevice->RealOut.ChannelIndex[LFE]         = 3;
        mDevice->RealOut.ChannelIndex[BackCenter]  = 4;
        mDevice->RealOut.ChannelIndex[SideLeft]    = 5;
        mDevice->RealOut.ChannelIndex[SideRight]   = 6;
        break;
    case DevFmtX71:
        mDevice->RealOut.ChannelIndex[FrontLeft]   = 0;
        mDevice->RealOut.ChannelIndex[FrontRight]  = 1;
        mDevice->RealOut.ChannelIndex[FrontCenter] = 2;
        mDevice->RealOut.ChannelIndex[LFE]         = 3;
        mDevice->RealOut.ChannelIndex[BackLeft]    = 4;
        mDevice->RealOut.ChannelIndex[BackRight]   = 5;
        mDevice->RealOut.ChannelIndex[SideLeft]    = 6;
        mDevice->RealOut.ChannelIndex[SideRight]   = 7;
        break;
    case DevFmtX3D71:
        mDevice->RealOut.ChannelIndex[FrontLeft]   = 0;
        mDevice->RealOut.ChannelIndex[FrontRight]  = 1;
        mDevice->RealOut.ChannelIndex[FrontCenter] = 2;
        mDevice->RealOut.ChannelIndex[LFE]         = 3;
        mDevice->RealOut.ChannelIndex[Aux0]        = 4;
        mDevice->RealOut.ChannelIndex[Aux1]        = 5;
        mDevice->RealOut.ChannelIndex[SideLeft]    = 6;
        mDevice->RealOut.ChannelIndex[SideRight]   = 7;
        break;
    case DevFmtAmbi3D:
        break;
    }
}

void BackendBase::setDefaultChannelOrder()
{
    mDevice->RealOut.ChannelIndex.fill(INVALID_CHANNEL_INDEX);

    switch(mDevice->FmtChans)
    {
    case DevFmtX51:
        mDevice->RealOut.ChannelIndex[FrontLeft]   = 0;
        mDevice->RealOut.ChannelIndex[FrontRight]  = 1;
        mDevice->RealOut.ChannelIndex[SideLeft]    = 2;
        mDevice->RealOut.ChannelIndex[SideRight]   = 3;
        mDevice->RealOut.ChannelIndex[FrontCenter] = 4;
        mDevice->RealOut.ChannelIndex[LFE]         = 5;
        return;
    case DevFmtX71:
        mDevice->RealOut.ChannelIndex[FrontLeft]   = 0;
        mDevice->RealOut.ChannelIndex[FrontRight]  = 1;
        mDevice->RealOut.ChannelIndex[BackLeft]    = 2;
        mDevice->RealOut.ChannelIndex[BackRight]   = 3;
        mDevice->RealOut.ChannelIndex[FrontCenter] = 4;
        mDevice->RealOut.ChannelIndex[LFE]         = 5;
        mDevice->RealOut.ChannelIndex[SideLeft]    = 6;
        mDevice->RealOut.ChannelIndex[SideRight]   = 7;
        return;
    case DevFmtX3D71:
        mDevice->RealOut.ChannelIndex[FrontLeft]   = 0;
        mDevice->RealOut.ChannelIndex[FrontRight]  = 1;
        mDevice->RealOut.ChannelIndex[Aux0]        = 2;
        mDevice->RealOut.ChannelIndex[Aux1]        = 3;
        mDevice->RealOut.ChannelIndex[FrontCenter] = 4;
        mDevice->RealOut.ChannelIndex[LFE]         = 5;
        mDevice->RealOut.ChannelIndex[SideLeft]    = 6;
        mDevice->RealOut.ChannelIndex[SideRight]   = 7;
        return;

    /* Same as WFX order */
    case DevFmtMono:
    case DevFmtStereo:
    case DevFmtQuad:
    case DevFmtX61:
    case DevFmtAmbi3D:
        setDefaultWFXChannelOrder();
        break;
    }
}