#ifndef IXR_H
#define IXR_H

#include "tier1/interface.h"
#include "tier2/iappsystem.h"
#include "materialsystem/imaterialsystem.h"
#include "trig.h"

struct XRRenderSurface_t
{
	uint32_t m_uWidth;
	uint32_t m_uHeight;
	Vector m_vPosition;
	Quat m_vRotation;
	float m_fFov;
};

enum EXRControllerType_t
{
	k_EXR_HandController,
	k_EXR_Hand,
};

enum EXRControllerSide_t
{
	k_EXRController_Left,
	k_EXRController_Right,
};
/* defined by openxr + steam frame */
enum EXRInputType_t
{
	k_EXRInput_FromString,

	k_EXRInput_Trackpad,
	k_EXRInput_Thumbstick,
	k_EXRInput_Joystick,
	k_EXRInput_Trigger,
	k_EXRInput_Throttle ,
	k_EXRInput_Trackball,
	k_EXRInput_Pedal,
	k_EXRInput_System,
	k_EXRInput_Dpad_Up,
	k_EXRInput_Dpad_Down,
	k_EXRInput_Dpad_Left,
	k_EXRInput_Dpad_Right,
	k_EXRInput_Diamond_Up,
	k_EXRInput_Diamond_Down,
	k_EXRInput_Diamond_Left,
	k_EXRInput_Diamond_Right,

	k_EXRInput_A,
	k_EXRInput_B,
	k_EXRInput_X,
	k_EXRInput_Y,
	k_EXRInput_Start,
	k_EXRInput_Home,
	k_EXRInput_End,
	k_EXRInput_Select,
	k_EXRInput_Volume_Up,
	k_EXRInput_Volume_Down,
	k_EXRInput_Mute_Mic,
	k_EXRInput_Play_Pause,
	k_EXRInput_Menu,
	k_EXRInput_View,
	k_EXRInput_Back,
	k_EXRInput_ThumbRest,
	k_EXRInput_Shoulder,
	k_EXRInput_Squeeze,
	k_EXRInput_Wheel,
	k_EXRInput_ThumbRestingSurfaces,


	k_EXRInput_Grip,
	k_EXRInput_Aim,
};

enum EXRInputActionType_t
{
	k_EXRInputAction_Touch,
	k_EXRInputAction_Click,
	k_EXRInputAction_Force,
	k_EXRInputAction_Value,
	k_EXRInputAction_X,
	k_EXRInputAction_Y,
	k_EXRInputAction_Twist,
	k_EXRInputAction_Pose,
	k_EXRInputAction_Proximity,
};

enum EXRValueType_t
{
	k_EXRValue_Bool,
	k_EXRValue_Float,
	k_EXRValue_Vector2,
	k_EXRValue_Pose,
};



union EXRInputValue_t
{
	EXRValueType_t type;
	struct
	{
		EXRValueType_t type;
		bool value;
	} b;

	struct
	{
		EXRValueType_t type;
		float value;
	} f32;

	struct
	{
		EXRValueType_t type;
		float x;
		float y;
	} f32x2;

	struct
	{
		EXRInputType_t type;
		Vector pos;
		Quat rot;
	} pose;
};

class IXRController;
class IXRHeadset;

typedef void ( *XRInputCallbackFn )( IXRController *pController, EXRInputType_t eType, const char *szType, EXRInputActionType_t action, EXRInputValue_t value );

abstract_class IXRController
{
public:
	virtual EXRControllerType_t GetControllerType() = 0;
	virtual EXRControllerSide_t GetControllerSide() = 0;
	virtual IXRHeadset *GetHeadset() = 0;
	virtual void SetInputCallback( XRInputCallbackFn fn ) = 0;
};

abstract_class IXRHeadset
{
public:
	virtual uint32_t GetSurfaceCount() = 0;
	virtual XRRenderSurface_t GetSurface( uint32_t i ) = 0;
	virtual void SetSurfaceImage( uint32_t i, IImage *pImage ) = 0;

	virtual uint32_t GetControllerCount() = 0;
	virtual IXRController *GetController( uint32_t i ) = 0;
};

abstract_class IXRManager: public IAppSystem2
{
public:
	virtual void Frame() = 0;
	virtual void PreRender() = 0;
	virtual void PostRender() = 0;
	virtual void CopySwapchain() = 0;
	virtual uint32_t GetHeadsetCount() = 0;
	virtual IXRHeadset *GetHeadset( uint32_t i ) = 0;
};

#define XR_INTERFACE_VERSION "XR001"
#define OPEN_XR_INTERFACE_VERSION "Open" XR_INTERFACE_VERSION


#endif