/*=========================================================================

	thing.cpp

	Author:		PKG
	Created: 
	Project:	Spongebob
	Purpose: 

	Copyright (c) 2001 Climax Development Ltd

===========================================================================*/

/*----------------------------------------------------------------------
	Includes
	-------- */

#include "thing\thing.h"

#ifndef	__PLAYER_PLAYER_H__
#include "player\player.h"
#endif

#ifndef __GAME_GAME_H__
#include "game\game.h"
#endif

#ifndef	__UTILS_HEADER__
#include	"utils\utils.h"
#endif


/*	Std Lib
	------- */

/*	Data
	---- */

/*----------------------------------------------------------------------
	Tyepdefs && Defines
	------------------- */

/*----------------------------------------------------------------------
	Structure defintions
	-------------------- */

/*----------------------------------------------------------------------
	Function Prototypes
	------------------- */

/*----------------------------------------------------------------------
	Vars
	---- */

CThing			*CThingManager::s_thingLists[CThing::MAX_TYPE]={NULL,NULL};
int				CThingManager::s_initialised=false;


/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void		CThingManager::init()
{
	int		i;

	ASSERT(!s_initialised);
	for(i=0;i<CThing::MAX_TYPE;i++)
	{
		s_thingLists[i]=NULL;
	}
	s_initialised=true;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void		CThingManager::shutdown()
{
	int		i;
	CThing	*thing;

	ASSERT(s_initialised);
	for(i=0;i<CThing::MAX_TYPE;i++)
	{
		while(s_thingLists[i])
		{
			thing=s_thingLists[i];
			thing->shutdown();
			delete thing;
		}
	}
	s_initialised=false;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void		CThingManager::thinkAllThings(int _frames)
{
	int		i;
	CThing	*thing;
	CThing	*thing1,*thing2;

	for(i=0;i<CThing::MAX_TYPE;i++)
	{
		thing=s_thingLists[i];
		while(thing)
		{
			thing->think(_frames);
			thing->updateCollisionArea();
			thing=thing->m_nextThing;
		}
	}

	CPlayer *player = GameScene.getPlayer();

	if ( player )
	{
		player->clearPlatform();
	}

	// Player -> Platform collision
	thing1=s_thingLists[CThing::TYPE_PLATFORM];
	thing2=s_thingLists[CThing::TYPE_PLAYER];

	thing2->setHasPlatformCollided( false );
	thing2->setNewCollidedPos( thing2->getPos() );

	while(thing1&&thing2)
	{
		if(thing1->canCollide()&&
		   thing1->checkCollisionAgainst(thing2, _frames))
		{

			thing1->collidedWith(thing2);
		}
		thing1=thing1->m_nextThing;
	}

	// Player -> Pickup collision
	thing1=s_thingLists[CThing::TYPE_PICKUP];
	thing2=s_thingLists[CThing::TYPE_PLAYER];
	while(thing1&&thing2)
	{
		if(thing1->canCollide()&&
		   thing1->checkCollisionAgainst(thing2, _frames))
		{
			thing1->collidedWith(thing2);
		}
		thing1=thing1->m_nextThing;
	}

	// Player -> Enemy collision
	thing1=s_thingLists[CThing::TYPE_ENEMY];
	thing2=s_thingLists[CThing::TYPE_PLAYER];
	while(thing1&&thing2)
	{
		if(thing1->canCollide()&&
		   thing1->checkCollisionAgainst(thing2, _frames))
		{
			thing1->collidedWith(thing2);
		}
		thing1=thing1->m_nextThing;
	}

	// Player -> Enemy projectile collision
	thing1=s_thingLists[CThing::TYPE_ENEMYPROJECTILE];
	thing2=s_thingLists[CThing::TYPE_PLAYER];
	while(thing1&&thing2)
	{
		if(thing1->canCollide()&&
		   thing1->checkCollisionAgainst(thing2, _frames))
		{
			thing1->collidedWith(thing2);
		}
		thing1=thing1->m_nextThing;
	}

	// Player -> Trigger collision
	thing1=s_thingLists[CThing::TYPE_TRIGGER];
	thing2=s_thingLists[CThing::TYPE_PLAYER];
	while(thing1&&thing2)
	{
		if(thing1->canCollide()&&
		   thing1->checkCollisionAgainst(thing2, _frames))
		{
			thing1->collidedWith(thing2);
		}
		thing1=thing1->m_nextThing;
	}

	// Enemy -> Player projectile collision
	thing1=s_thingLists[CThing::TYPE_PLAYERPROJECTILE];
	thing2=s_thingLists[CThing::TYPE_ENEMY];
	while(thing1)
	{
		while(thing2)
		{
			if(thing1->canCollide()&&
			   thing2->canCollide()&&
			   thing1->checkCollisionAgainst(thing2, _frames))
			{
				thing1->collidedWith(thing2);
			}
			thing2=thing2->m_nextThing;
		}
		thing1=thing1->m_nextThing;
	}

}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void		CThingManager::renderAllThings()
{
	int		i;
	CThing	*thing;

	for(i=0;i<CThing::MAX_TYPE;i++)
	{
		thing=s_thingLists[i];
		while(thing)
		{
			thing->render();
			thing=thing->m_nextThing;
		}
	}
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void		CThingManager::processEventAllThings(GAME_EVENT _event,CThing *_sourceThing)
{
	int		i;
	CThing	*thing;

	for(i=0;i<CThing::MAX_TYPE;i++)
	{
		thing=s_thingLists[i];
		while(thing)
		{
			thing->processEvent(_event,_sourceThing);
			thing=thing->m_nextThing;
		}
	}
}

/*----------------------------------------------------------------------
	Function:
	Purpose:	Searches through a list of things to check for collision against an area.
				The first time this is called, _continue should be false. If no colliding things are found then
				NULL will be returned. If a colliding thing is found then it's address gets returned. To continue
				searching through the list for the next colliding thing, call the function again with _continue set
				to true.
				NB: This function could probly cause weird bugs if not used properly! BE AWARE!
	Params:		*_area		Area to check against
				_type		Type of thing to search for
				_continue	If false then the list is searched from the start, if true then the search continues
							from the last thing that was found ( um.. see above )
	Returns:
  ---------------------------------------------------------------------- */
CThing		*CThingManager::checkCollisionAreaAgainstThings(CRECT *_area,int _type,int _continue)
{
	static CThing	*thing=NULL;

	ASSERT(_type<CThing::MAX_TYPE);

	if(_continue)
	{
		ASSERT(thing);
		thing=thing->m_nextThing;
	}
	else
	{
		thing=s_thingLists[_type];
	}
	while(thing)
	{
		if(thing->canCollide()&&
		   thing->checkCollisionAgainstArea(_area))
		{
			return thing;
		}
		thing=thing->m_nextThing;
	}

	return NULL;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void			CThingManager::addToThingList(CThing *_this)
{
	_this->m_nextThing=s_thingLists[_this->getThingType()];
	s_thingLists[_this->getThingType()]=_this;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void			CThingManager::removeFromThingList(CThing *_this)
{
	CThing	*prevThing,*thing;

	prevThing=NULL;
	thing=s_thingLists[_this->getThingType()];
	while(thing!=_this)
	{
		prevThing=thing;
		thing=thing->m_nextThing;
		ASSERT(thing);	// Not in the list!?!?
	}
	if(prevThing)
	{
		prevThing->m_nextThing=_this->m_nextThing;
	}
	else
	{
		s_thingLists[_this->getThingType()]=_this->m_nextThing;
	}
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CThing::init()
{
	Parent=NULL;
	Next=NULL;

	Pos.vx=Pos.vy=10;

	// Add to thing list
	CThingManager::addToThingList(this);

	setCollisionSize(20,20);	// Some temporary defaults.. (pkg)
	setCollisionCentreOffset(0,0);
	m_collisionAngle = 0;
	m_centreCollision = false;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CThing::shutdown()
{
	if (Parent) 
	{ // Is child
		Parent->removeChild(this);
	}
	else
	{ // Is Parent
		removeAllChild();
	}

	// Remove from thing list
	CThingManager::removeFromThingList(this);
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CThing::think(int _frames)
{
	PosDelta.vx=Pos.vx-PosLast.vx; 
	PosDelta.vy=Pos.vy-PosLast.vy;
	PosLast=Pos;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
#if defined (__USER_paul__) || defined (__USER_charles__)
int showthings=true;
#include "gfx\prim.h"
#include "level\level.h"
void	CThing::render()
{
	if(showthings)
	{
		DVECTOR	ofs;
		CRECT	area;

		ofs=CLevel::getCameraPos();

		area=getCollisionArea();
		area.x1-=ofs.vx;
		area.y1-=ofs.vy;
		area.x2-=ofs.vx;
		area.y2-=ofs.vy;

		if(area.x1<=511&&area.x2>=0&&
		   area.y1<=255&&area.y2>=0)
		{
			area=getCollisionArea();

			SVECTOR points[4];
			VECTOR vecPoints[4];

			points[0].vx = area.x1 - Pos.vx;
			points[0].vy = area.y1 - Pos.vy;

			points[1].vx = area.x1 - Pos.vx;
			points[1].vy = area.y2 - Pos.vy;

			points[2].vx = area.x2 - Pos.vx;
			points[2].vy = area.y2 - Pos.vy;

			points[3].vx = area.x2 - Pos.vx;
			points[3].vy = area.y1 - Pos.vy;

			MATRIX mtx;

			SetIdentNoTrans(&mtx );
			RotMatrixZ( m_collisionAngle, &mtx );

			ApplyMatrix( &mtx, &points[0], &vecPoints[0] );
			ApplyMatrix( &mtx, &points[1], &vecPoints[1] );
			ApplyMatrix( &mtx, &points[2], &vecPoints[2] );
			ApplyMatrix( &mtx, &points[3], &vecPoints[3] );

			vecPoints[0].vx += Pos.vx - ofs.vx;
			vecPoints[0].vy += Pos.vy - ofs.vy;

			vecPoints[1].vx += Pos.vx - ofs.vx;
			vecPoints[1].vy += Pos.vy - ofs.vy;

			vecPoints[2].vx += Pos.vx - ofs.vx;
			vecPoints[2].vy += Pos.vy - ofs.vy;

			vecPoints[3].vx += Pos.vx - ofs.vx;
			vecPoints[3].vy += Pos.vy - ofs.vy;

			//DrawLine(area.x1,area.y1,area.x1,area.y2,255,255,255,0);
			//DrawLine(area.x1,area.y2,area.x2,area.y2,255,255,255,0);
			//DrawLine(area.x2,area.y2,area.x2,area.y1,255,255,255,0);
			//DrawLine(area.x2,area.y1,area.x1,area.y1,255,255,255,0);

			DrawLine( vecPoints[0].vx, vecPoints[0].vy, vecPoints[1].vx, vecPoints[1].vy,255,255,255,0);
			DrawLine( vecPoints[1].vx, vecPoints[1].vy, vecPoints[2].vx, vecPoints[2].vy,255,255,255,0);
			DrawLine( vecPoints[2].vx, vecPoints[2].vy, vecPoints[3].vx, vecPoints[3].vy,255,255,255,0);
			DrawLine( vecPoints[3].vx, vecPoints[3].vy, vecPoints[0].vx, vecPoints[0].vy,255,255,255,0);

			area.x1=Pos.vx-10-ofs.vx;
			area.y1=Pos.vy-10-ofs.vy;
			area.x2=Pos.vx+10-ofs.vx;
			area.y2=Pos.vy+10-ofs.vy;
			DrawLine(area.x1,area.y1,area.x2,area.y2,255,0,0,0);
			DrawLine(area.x2,area.y1,area.x1,area.y2,255,0,0,0);
		}
	}
}
#else
void	CThing::render()
{
}
#endif

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CThing::addChild(CThing *Child)
{
CThing	*List=Next;

	if ( List )
	{
// Find end of list
		while (List->Next) 
		{
			List=List->Next;
		}
		List->Next=Child;
		Child->Parent=this;
	}
	else
	{
// List does not exist, create
		Next = Child;
		Child->Parent=this;
	}
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CThing::removeChild(CThing *Child)
{
CThing	*List=Next;
CThing	*Last=NULL;

// Find Child
		while ( List != Child && List->Next )
		{
			Last = List;
			List = List->Next;
		}

// if there are no more links to continue down, the current 'List' must either be the correct item, or the item does not
// exist in the list at all

		ASSERT( List == Child );

		if ( Last )
		{
			Last->Next = List->Next;
		}
		else
		{
			this->Next = List->Next;
		}

		Child->Parent=NULL;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CThing::removeAllChild()
{
CThing	*List=Next;

		while (List)
		{
			CThing	*Next=List->Next;
			List->Parent=NULL;
			List->Next=NULL;
			List=Next;
		}
		Next=NULL;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
bool	CThing::hasChild(CThing *Child)
{
	CThing *nextChild = Next;

	while( nextChild )
	{
		if ( nextChild == Child )
		{
			return( true );
		}

		nextChild = nextChild->Next;
	}

	return( false );
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CThing::setCollisionSize(int _w,int _h)
{
	m_collisionSize.vx=_w;
	m_collisionSize.vy=_h;
	if(m_collisionSize.vx>m_collisionSize.vy)
	{
		m_collisionRadius=m_collisionSize.vx;
	}
	else
	{
		m_collisionRadius=m_collisionSize.vy;
	}
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CThing::updateCollisionArea()
{
	m_collisionCentre.vx=Pos.vx+m_collisionCentreOffset.vx;
	m_collisionCentre.vy=Pos.vy+m_collisionCentreOffset.vy;
	m_collisionArea.x1=m_collisionCentre.vx-(m_collisionSize.vx/2);
	m_collisionArea.x2=m_collisionArea.x1+m_collisionSize.vx;
	m_collisionArea.y1=m_collisionCentre.vy-(m_collisionSize.vy/2);
	m_collisionArea.y2=m_collisionArea.y1+m_collisionSize.vy;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */

s32		CThing::getNewYPos(CThing *_thisThing)
{
	CRECT	thisRect;
	thisRect = getCollisionArea();

	if ( thisRect.y1 < thisRect.y2 )
	{
		return( thisRect.y1 );
	}
	else
	{
		return( thisRect.y2 );
	}
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
int		CThing::checkCollisionAgainst(CThing *_thisThing, int _frames)
{
	DVECTOR	pos,thisThingPos;
	int		radius;
	int		collided;

	pos=getCollisionCentre();
	thisThingPos=_thisThing->getCollisionCentre();

	radius=getCollisionRadius()+_thisThing->getCollisionRadius();
	collided=false;
	if(abs(pos.vx-thisThingPos.vx)<radius&&
	   abs(pos.vy-thisThingPos.vy)<radius)
	{
		CRECT	thisRect,thatRect;

		thisRect=getCollisionArea();

		thatRect=_thisThing->getCollisionArea();

		if(((thisRect.x1>=thatRect.x1&&thisRect.x1<=thatRect.x2)||(thisRect.x2>=thatRect.x1&&thisRect.x2<=thatRect.x2)||(thisRect.x1<=thatRect.x1&&thisRect.x2>=thatRect.x2))&&
		   ((thisRect.y1>=thatRect.y1&&thisRect.y1<=thatRect.y2)||(thisRect.y2>=thatRect.y1&&thisRect.y2<=thatRect.y2)||(thisRect.y1<=thatRect.y1&&thisRect.y2>=thatRect.y2)))
		{
			collided=true;
		}
	}

	return collided;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
int		CThing::checkCollisionAgainstArea(CRECT *_rect)
{
	CRECT	thisRect;
	int		ret;

	thisRect=getCollisionArea();
	ret=false;

	if(((thisRect.x1>=_rect->x1&&thisRect.x1<=_rect->x2)||(thisRect.x2>=_rect->x1&&thisRect.x2<=_rect->x2)||(thisRect.x1<=_rect->x1&&thisRect.x2>=_rect->x2))&&
	   ((thisRect.y1>=_rect->y1&&thisRect.y1<=_rect->y2)||(thisRect.y2>=_rect->y1&&thisRect.y2<=_rect->y2)||(thisRect.y1<=_rect->y1&&thisRect.y2>=_rect->y2)))
	{
		ret=true;
	}

	return ret;
}

/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CThing::processEvent(GAME_EVENT _event,CThing *_sourceThing)
{
	// do nothing by default - ignore event
}


/*----------------------------------------------------------------------
	Function:
	Purpose:
	Params:
	Returns:
  ---------------------------------------------------------------------- */
void	CTriggerThing::setPositionAndSize(int _x,int _y,int _w,int _h)
{
	Pos.vx=_x+(_w/2);
	Pos.vy=_y+(_h/2);
	setCollisionSize(_w,_h);
}

/*===========================================================================
end */