/************************************************************************************

Filename    :   OVR_Linux_HMDDevice.h
Content     :   Linux HMDDevice implementation
Created     :   June 17, 2013
Authors     :   Brant Lewis

Copyright   :   Copyright 2013 Oculus VR, Inc. All Rights reserved.

Licensed under the Oculus VR SDK License Version 2.0 (the "License"); 
you may not use the Oculus VR SDK except in compliance with the License, 
which is provided at the time of installation or download, or which 
otherwise accompanies this software in either electronic or hard copy form.

You may obtain a copy of the License at

http://www.oculusvr.com/licenses/LICENSE-2.0 

Unless required by applicable law or agreed to in writing, the Oculus VR SDK 
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

*************************************************************************************/

#include "OVR_Linux_HMDDevice.h"

#include "OVR_Linux_DeviceManager.h"

#include "OVR_Profile.h"

#include <X11/Xlib.h>
#include <X11/extensions/Xinerama.h>

namespace OVR { namespace Linux {

//-------------------------------------------------------------------------------------

HMDDeviceCreateDesc::HMDDeviceCreateDesc(DeviceFactory* factory, const String& displayDeviceName, long dispId)
        : DeviceCreateDesc(factory, Device_HMD),
          DisplayDeviceName(displayDeviceName),
          DesktopX(0), DesktopY(0), Contents(0), EyeToScreenDistance(0),
          HResolution(0), VResolution(0), HScreenSize(0), VScreenSize(0),
          DisplayId(dispId)
{
    DeviceId = DisplayDeviceName;
    for (int i=0; i<4; i++)
        DistortionK[i] = 0;
}

HMDDeviceCreateDesc::HMDDeviceCreateDesc(const HMDDeviceCreateDesc& other)
        : DeviceCreateDesc(other.pFactory, Device_HMD),
          DeviceId(other.DeviceId), DisplayDeviceName(other.DisplayDeviceName),
          DesktopX(other.DesktopX), DesktopY(other.DesktopY), Contents(other.Contents),
          HResolution(other.HResolution), VResolution(other.VResolution),
          HScreenSize(other.HScreenSize), VScreenSize(other.VScreenSize),
          DisplayId(other.DisplayId), EyeToScreenDistance(other.EyeToScreenDistance)
{
    for (int i=0; i<4; i++)
        DistortionK[i] = other.DistortionK[i];
}

HMDDeviceCreateDesc::MatchResult HMDDeviceCreateDesc::MatchDevice(const DeviceCreateDesc& other,
                                                                  DeviceCreateDesc** pcandidate) const
{
    if ((other.Type != Device_HMD) || (other.pFactory != pFactory))
        return Match_None;

    // There are several reasons we can come in here:
    //   a) Matching this HMD Monitor created desc to OTHER HMD Monitor desc
    //          - Require exact device DeviceId/DeviceName match
    //   b) Matching SensorDisplayInfo created desc to OTHER HMD Monitor desc
    //          - This DeviceId is empty; becomes candidate
    //   c) Matching this HMD Monitor created desc to SensorDisplayInfo desc
    //          - This other.DeviceId is empty; becomes candidate

    const HMDDeviceCreateDesc& s2 = (const HMDDeviceCreateDesc&) other;

    if ((DeviceId == s2.DeviceId) &&
        (DisplayId == s2.DisplayId))
    {
        // Non-null DeviceId may match while size is different if screen size was overwritten
        // by SensorDisplayInfo in prior iteration.
        if (!DeviceId.IsEmpty() ||
             ((HScreenSize == s2.HScreenSize) &&
              (VScreenSize == s2.VScreenSize)) )
        {            
            *pcandidate = 0;
            return Match_Found;
        }
    }


    // DisplayInfo takes precedence, although we try to match it first.
    if ((HResolution == s2.HResolution) &&
        (VResolution == s2.VResolution) &&
        (HScreenSize == s2.HScreenSize) &&
        (VScreenSize == s2.VScreenSize))
    {
        if (DeviceId.IsEmpty() && !s2.DeviceId.IsEmpty())
        {
            *pcandidate = const_cast<DeviceCreateDesc*>((const DeviceCreateDesc*)this);
            return Match_Candidate;
        }

        *pcandidate = 0;
        return Match_Found;
    }
    
    // SensorDisplayInfo may override resolution settings, so store as candidate.
    if (s2.DeviceId.IsEmpty())
    {        
        *pcandidate = const_cast<DeviceCreateDesc*>((const DeviceCreateDesc*)this);
        return Match_Candidate;
    }
    // OTHER HMD Monitor desc may initialize DeviceName/Id
    else if (DeviceId.IsEmpty())
    {
        *pcandidate = const_cast<DeviceCreateDesc*>((const DeviceCreateDesc*)this);
        return Match_Candidate;
    }
    
    return Match_None;
}


bool HMDDeviceCreateDesc::UpdateMatchedCandidate(const DeviceCreateDesc& other, 
                                                 bool* newDeviceFlag)
{
    // This candidate was the the "best fit" to apply sensor DisplayInfo to.
    OVR_ASSERT(other.Type == Device_HMD);
    
    const HMDDeviceCreateDesc& s2 = (const HMDDeviceCreateDesc&) other;

    // Force screen size on resolution from SensorDisplayInfo.
    // We do this because USB detection is more reliable as compared to HDMI EDID,
    // which may be corrupted by splitter reporting wrong monitor 
    if (s2.DeviceId.IsEmpty())
    {
        HScreenSize = s2.HScreenSize;
        VScreenSize = s2.VScreenSize;
        Contents |= Contents_Screen;

        if (s2.Contents & HMDDeviceCreateDesc::Contents_Distortion)
        {
            memcpy(DistortionK, s2.DistortionK, sizeof(float)*4);
            Contents |= Contents_Distortion;
        }
        DeviceId          = s2.DeviceId;
        DisplayId         = s2.DisplayId;
        DisplayDeviceName = s2.DisplayDeviceName;
        if (newDeviceFlag) *newDeviceFlag = true;
    }
    else if (DeviceId.IsEmpty())
    {
        DeviceId          = s2.DeviceId;
        DisplayId         = s2.DisplayId;
        DisplayDeviceName = s2.DisplayDeviceName;

		// ScreenSize and Resolution are NOT assigned here, since they may have
		// come from a sensor DisplayInfo (which has precedence over HDMI).

        if (newDeviceFlag) *newDeviceFlag = true;
    }
    else
    {
        if (newDeviceFlag) *newDeviceFlag = false;
    }

    return true;
}

bool HMDDeviceCreateDesc::MatchDevice(const String& path)
{
    return DeviceId.CompareNoCase(path) == 0;
}

//-------------------------------------------------------------------------------------
// ***** HMDDeviceFactory

HMDDeviceFactory HMDDeviceFactory::Instance;

void HMDDeviceFactory::EnumerateDevices(EnumerateVisitor& visitor)
{
    // For now we'll assume the Rift DK1 is attached in extended monitor mode. Ultimately we need to
    // use XFree86 to enumerate X11 screens in case the Rift is attached as a separate screen. We also
    // need to be able to read the EDID manufacturer product code to be able to differentiate between
    // Rift models.

    bool foundHMD = false;

    Display* display = XOpenDisplay(NULL);
    if (display && XineramaIsActive(display))
    {
        int numberOfScreens;
        XineramaScreenInfo* screens = XineramaQueryScreens(display, &numberOfScreens);

        for (int i = 0; i < numberOfScreens; i++)
        {
            XineramaScreenInfo screenInfo = screens[i];

            if (screenInfo.width == 1280 && screenInfo.height == 800)
            {
                String deviceName = "OVR0001";

                HMDDeviceCreateDesc hmdCreateDesc(this, deviceName, i);
                hmdCreateDesc.SetScreenParameters(screenInfo.x_org, screenInfo.y_org, 1280, 800, 0.14976f, 0.0936f);

                OVR_DEBUG_LOG_TEXT(("DeviceManager - HMD Found %s - %d\n",
                                    deviceName.ToCStr(), i));

                // Notify caller about detected device. This will call EnumerateAddDevice
                // if the this is the first time device was detected.
                visitor.Visit(hmdCreateDesc);
                foundHMD = true;
                break;
            }
        }

        XFree(screens);
    }


    // Real HMD device is not found; however, we still may have a 'fake' HMD
    // device created via SensorDeviceImpl::EnumerateHMDFromSensorDisplayInfo.
    // Need to find it and set 'Enumerated' to true to avoid Removal notification.
    if (!foundHMD)
    {
        Ptr<DeviceCreateDesc> hmdDevDesc = getManager()->FindDevice("", Device_HMD);
        if (hmdDevDesc)
            hmdDevDesc->Enumerated = true;
    }
}

DeviceBase* HMDDeviceCreateDesc::NewDeviceInstance()
{
    return new HMDDevice(this);
}

bool HMDDeviceCreateDesc::Is7Inch() const
{
    return (strstr(DeviceId.ToCStr(), "OVR0001") != 0) || (Contents & Contents_7Inch);
}

Profile* HMDDeviceCreateDesc::GetProfileAddRef() const
{
    // Create device may override profile name, so get it from there is possible.
    ProfileManager* profileManager = GetManagerImpl()->GetProfileManager();
    ProfileType     profileType    = GetProfileType();
    const char *    profileName    = pDevice ?
                        ((HMDDevice*)pDevice)->GetProfileName() :
                        profileManager->GetDefaultProfileName(profileType);
    
    return profileName ? 
        profileManager->LoadProfile(profileType, profileName) :
        profileManager->GetDeviceDefaultProfile(profileType);
}


bool HMDDeviceCreateDesc::GetDeviceInfo(DeviceInfo* info) const
{
    if ((info->InfoClassType != Device_HMD) &&
        (info->InfoClassType != Device_None))
        return false;

    bool is7Inch = Is7Inch();

    OVR_strcpy(info->ProductName,  DeviceInfo::MaxNameLength,
               is7Inch ? "Oculus Rift DK1" :
			   ((HResolution >= 1920) ? "Oculus Rift DK HD" : "Oculus Rift DK1-Prototype") );
    OVR_strcpy(info->Manufacturer, DeviceInfo::MaxNameLength, "Oculus VR");
    info->Type    = Device_HMD;
    info->Version = 0;

    // Display detection.
    if (info->InfoClassType == Device_HMD)
    {
        HMDInfo* hmdInfo = static_cast<HMDInfo*>(info);

        hmdInfo->DesktopX               = DesktopX;
        hmdInfo->DesktopY               = DesktopY;
        hmdInfo->HResolution            = HResolution;
        hmdInfo->VResolution            = VResolution;
        hmdInfo->HScreenSize            = HScreenSize;
        hmdInfo->VScreenSize            = VScreenSize;
        hmdInfo->VScreenCenter          = VScreenSize * 0.5f;
        hmdInfo->InterpupillaryDistance = 0.064f;  // Default IPD; should be configurable.
        hmdInfo->LensSeparationDistance = 0.0635f;

        // Obtain IPD from profile.
        Ptr<Profile> profile = *GetProfileAddRef();

        if (profile)
        {
            hmdInfo->InterpupillaryDistance = profile->GetIPD();
            // TBD: Switch on EyeCup type.
        }

        if (Contents & Contents_Distortion)
        {
            memcpy(hmdInfo->DistortionK, DistortionK, sizeof(float)*4);
            hmdInfo->EyeToScreenDistance = EyeToScreenDistance;
        }
        else
        {						
			if (is7Inch)
            {
                // 7" screen.
                hmdInfo->DistortionK[0]      = 1.0f;
                hmdInfo->DistortionK[1]      = 0.22f;
                hmdInfo->DistortionK[2]      = 0.24f;
                hmdInfo->EyeToScreenDistance = 0.041f;
            }
            else
            {
                hmdInfo->DistortionK[0]      = 1.0f;
                hmdInfo->DistortionK[1]      = 0.18f;
                hmdInfo->DistortionK[2]      = 0.115f;

				if (HResolution == 1920)
					hmdInfo->EyeToScreenDistance = 0.040f;
				else
					hmdInfo->EyeToScreenDistance = 0.0387f;
            }
        }

        hmdInfo->ChromaAbCorrection[0] = 0.996f;
        hmdInfo->ChromaAbCorrection[1] = -0.004f;
        hmdInfo->ChromaAbCorrection[2] = 1.014f;
        hmdInfo->ChromaAbCorrection[3] = 0.0f;

        OVR_strcpy(hmdInfo->DisplayDeviceName, sizeof(hmdInfo->DisplayDeviceName),
                   DisplayDeviceName.ToCStr());
        hmdInfo->DisplayId = DisplayId;
    }

    return true;
}

//-------------------------------------------------------------------------------------
// ***** HMDDevice

HMDDevice::HMDDevice(HMDDeviceCreateDesc* createDesc)
    : OVR::DeviceImpl<OVR::HMDDevice>(createDesc, 0)
{
}
HMDDevice::~HMDDevice()
{
}

bool HMDDevice::Initialize(DeviceBase* parent)
{
    pParent = parent;

    // Initialize user profile to default for device.
    ProfileManager* profileManager = GetManager()->GetProfileManager();    
    ProfileName = profileManager->GetDefaultProfileName(getDesc()->GetProfileType());

    return true;
}
void HMDDevice::Shutdown()
{
    ProfileName.Clear();
    pCachedProfile.Clear();
    pParent.Clear();
}

Profile* HMDDevice::GetProfile() const
{    
    if (!pCachedProfile)
        pCachedProfile = *getDesc()->GetProfileAddRef();
    return pCachedProfile.GetPtr();
}

const char* HMDDevice::GetProfileName() const
{
    return ProfileName.ToCStr();
}

bool HMDDevice::SetProfileName(const char* name)
{
    pCachedProfile.Clear();
    if (!name)
    {
        ProfileName.Clear();
        return 0;
    }
    if (GetManager()->GetProfileManager()->HasProfile(getDesc()->GetProfileType(), name))
    {
        ProfileName = name;
        return true;
    }
    return false;
}

OVR::SensorDevice* HMDDevice::GetSensor()
{
    // Just return first sensor found since we have no way to match it yet.
    OVR::SensorDevice* sensor = GetManager()->EnumerateDevices<SensorDevice>().CreateDevice();
    if (sensor)
        sensor->SetCoordinateFrame(SensorDevice::Coord_HMD);
    return sensor;
}

}} // namespace OVR::Linux