// Copyright (C) 2002-2009 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#include "CSceneNodeAnimatorCameraMaya.h"
#include "ICursorControl.h"
#include "ICameraSceneNode.h"
#include "SViewFrustum.h"
#include "ISceneManager.h"

namespace irr
{
namespace scene
{

//! constructor
CSceneNodeAnimatorCameraMaya::CSceneNodeAnimatorCameraMaya(gui::ICursorControl* cursor, f32 rotate, f32 zoom, f32 translate)
	: CursorControl(cursor), Zooming(false), Rotating(false), Moving(false),
	Translating(false), ZoomSpeed(zoom), RotateSpeed(rotate), TranslateSpeed(translate),
	CurrentZoom(70.0f), RotX(0.0f), RotY(0.0f), OldCamera(0), MousePos(0.5f, 0.5f)
{
	#ifdef _DEBUG
	setDebugName("CSceneNodeAnimatorCameraMaya");
	#endif

	if (CursorControl)
	{
		CursorControl->grab();
		MousePos = CursorControl->getRelativePosition();
	}

	allKeysUp();
}


//! destructor
CSceneNodeAnimatorCameraMaya::~CSceneNodeAnimatorCameraMaya()
{
	if (CursorControl)
		CursorControl->drop();
}


//! It is possible to send mouse and key events to the camera. Most cameras
//! may ignore this input, but camera scene nodes which are created for
//! example with scene::ISceneManager::addMayaCameraSceneNode or
//! scene::ISceneManager::addMeshViewerCameraSceneNode, may want to get this input
//! for changing their position, look at target or whatever.
bool CSceneNodeAnimatorCameraMaya::OnEvent(const SEvent& event)
{
	if (event.EventType != EET_MOUSE_INPUT_EVENT)
		return false;

	switch(event.MouseInput.Event)
	{
	case EMIE_LMOUSE_PRESSED_DOWN:
		MouseKeys[0] = true;
		break;
	case EMIE_RMOUSE_PRESSED_DOWN:
		MouseKeys[2] = true;
		break;
	case EMIE_MMOUSE_PRESSED_DOWN:
		MouseKeys[1] = true;
		break;
	case EMIE_LMOUSE_LEFT_UP:
		MouseKeys[0] = false;
		break;
	case EMIE_RMOUSE_LEFT_UP:
		MouseKeys[2] = false;
		break;
	case EMIE_MMOUSE_LEFT_UP:
		MouseKeys[1] = false;
		break;
	case EMIE_MOUSE_MOVED:
		MousePos = CursorControl->getRelativePosition();
		break;
	case EMIE_MOUSE_WHEEL:
	case EMIE_LMOUSE_DOUBLE_CLICK:
	case EMIE_RMOUSE_DOUBLE_CLICK:
	case EMIE_MMOUSE_DOUBLE_CLICK:
	case EMIE_LMOUSE_TRIPLE_CLICK:
	case EMIE_RMOUSE_TRIPLE_CLICK:
	case EMIE_MMOUSE_TRIPLE_CLICK:
	case EMIE_COUNT:
		return false;
	}
	return true;
}


//! OnAnimate() is called just before rendering the whole scene.
//! nodes may calculate or store animations here, and may do other useful things,
//! dependent on what they are.
void CSceneNodeAnimatorCameraMaya::animateNode(ISceneNode *node, u32 timeMs)
{
	//Alt + LM = Rotate around camera pivot
	//Alt + LM + MM = Dolly forth/back in view direction (speed % distance camera pivot - max distance to pivot)
	//Alt + MM = Move on camera plane (Screen center is about the mouse pointer, depending on move speed)

	if (!node || node->getType() != ESNT_CAMERA)
		return;

	ICameraSceneNode* camera = static_cast<ICameraSceneNode*>(node);

	// If the camera isn't the active camera, and receiving input, then don't process it.
	if(!camera->isInputReceiverEnabled())
		return;

	scene::ISceneManager * smgr = camera->getSceneManager();
	if(smgr && smgr->getActiveCamera() != camera)
		return;

	if (OldCamera != camera)
	{
		OldTarget = camera->getTarget();
		OldCamera = camera;
		LastCameraTarget = OldTarget;
	}
	else
	{
		OldTarget += camera->getTarget() - LastCameraTarget;
	}

	core::vector3df target = camera->getTarget();

	f32 nRotX = RotX;
	f32 nRotY = RotY;
	f32 nZoom = CurrentZoom;

	if ( (isMouseKeyDown(0) && isMouseKeyDown(2)) || isMouseKeyDown(1) )
	{
		if (!Zooming)
		{
			ZoomStart = MousePos;
			Zooming = true;
			nZoom = CurrentZoom;
		}
		else
		{
			const f32 targetMinDistance = 0.1f;
			nZoom += (ZoomStart.X - MousePos.X) * ZoomSpeed;

			if (nZoom < targetMinDistance) // jox: fixed bug: bounce back when zooming to close
				nZoom = targetMinDistance;
		}
	}
	else if (Zooming)
	{
		const f32 old = CurrentZoom;
		CurrentZoom = CurrentZoom + (ZoomStart.X - MousePos.X ) * ZoomSpeed;
		nZoom = CurrentZoom;

		if (nZoom < 0)
			nZoom = CurrentZoom = old;
		Zooming = false;
	}

	// Translation ---------------------------------

	core::vector3df translate(OldTarget), upVector(camera->getUpVector());

	core::vector3df tvectX = Pos - target;
	tvectX = tvectX.crossProduct(upVector);
	tvectX.normalize();

	const SViewFrustum* const va = camera->getViewFrustum();
	core::vector3df tvectY = (va->getFarLeftDown() - va->getFarRightDown());
	tvectY = tvectY.crossProduct(upVector.Y > 0 ? Pos - target : target - Pos);
	tvectY.normalize();

	if (isMouseKeyDown(2) && !Zooming)
	{
		if (!Translating)
		{
			TranslateStart = MousePos;
			Translating = true;
		}
		else
		{
			translate +=  tvectX * (TranslateStart.X - MousePos.X)*TranslateSpeed +
			              tvectY * (TranslateStart.Y - MousePos.Y)*TranslateSpeed;
		}
	}
	else if (Translating)
	{
		translate += tvectX * (TranslateStart.X - MousePos.X)*TranslateSpeed +
		             tvectY * (TranslateStart.Y - MousePos.Y)*TranslateSpeed;
		OldTarget = translate;
		Translating = false;
	}

	// Rotation ------------------------------------

	if (isMouseKeyDown(0) && !Zooming)
	{
		if (!Rotating)
		{
			RotateStart = MousePos;
			Rotating = true;
			nRotX = RotX;
			nRotY = RotY;
		}
		else
		{
			nRotX += (RotateStart.X - MousePos.X) * RotateSpeed;
			nRotY += (RotateStart.Y - MousePos.Y) * RotateSpeed;
		}
	}
	else if (Rotating)
	{
		RotX += (RotateStart.X - MousePos.X) * RotateSpeed;
		RotY += (RotateStart.Y - MousePos.Y) * RotateSpeed;
		nRotX = RotX;
		nRotY = RotY;
		Rotating = false;
	}

	// Set Pos ------------------------------------

	target = translate;

	Pos.X = nZoom + target.X;
	Pos.Y = target.Y;
	Pos.Z = target.Z;

	Pos.rotateXYBy(nRotY, target);
	Pos.rotateXZBy(-nRotX, target);

	// Rotation Error ----------------------------

	// jox: fixed bug: jitter when rotating to the top and bottom of y
	upVector.set(0,1,0);
	upVector.rotateXYBy(-nRotY);
	upVector.rotateXZBy(-nRotX+180.f);

	camera->setPosition(Pos);
	camera->setTarget(target);
	camera->setUpVector(upVector);
	LastCameraTarget = camera->getTarget();
}


bool CSceneNodeAnimatorCameraMaya::isMouseKeyDown(s32 key)
{
	return MouseKeys[key];
}


void CSceneNodeAnimatorCameraMaya::allKeysUp()
{
	for (s32 i=0; i<3; ++i)
		MouseKeys[i] = false;
}


//! Sets the rotation speed
void CSceneNodeAnimatorCameraMaya::setRotateSpeed(f32 speed)
{
	RotateSpeed = speed;
}


//! Sets the movement speed
void CSceneNodeAnimatorCameraMaya::setMoveSpeed(f32 speed)
{
	TranslateSpeed = speed;
}


//! Sets the zoom speed
void CSceneNodeAnimatorCameraMaya::setZoomSpeed(f32 speed)
{
	ZoomSpeed = speed;
}


//! Gets the rotation speed
f32 CSceneNodeAnimatorCameraMaya::getRotateSpeed() const
{
	return RotateSpeed;
}


// Gets the movement speed
f32 CSceneNodeAnimatorCameraMaya::getMoveSpeed() const
{
	return TranslateSpeed;
}


//! Gets the zoom speed
f32 CSceneNodeAnimatorCameraMaya::getZoomSpeed() const
{
	return ZoomSpeed;
}

ISceneNodeAnimator* CSceneNodeAnimatorCameraMaya::createClone(ISceneNode* node, ISceneManager* newManager)
{
	CSceneNodeAnimatorCameraMaya * newAnimator =
		new CSceneNodeAnimatorCameraMaya(CursorControl, RotateSpeed, ZoomSpeed, TranslateSpeed);
	return newAnimator;
}

} // end namespace
} // end namespace