#include "ObjectFactory.h"
#include "uox3.h"
#include <mutex>

#define HASHMAX 2477 // hashmax must be a prime for maximum performce.

inline SERIAL HashSerial( SERIAL toHash )
{
	return toHash%HASHMAX;
}

/** This class is responsible for the creation and destruction of ingame
 objects and should mean that we can take chars[] and items[] out of scope
 */

//o-----------------------------------------------------------------------------------------------o

ObjectFactory& ObjectFactory::getSingleton( void )
{
	std::mutex lock;
	std::scoped_lock scope(lock) ;
	static ObjectFactory instance ;
	return instance ;
}
//o-----------------------------------------------------------------------------------------------o

// Starting Characters with a serial of 1, rather than 0. The UO Client doesn't always respond well to a serial of 0 -   6/21/08
ObjectFactory::ObjectFactory() : nextPC( 1 ), nextNPC( 1 ), nextItem( BASEITEMSERIAL ), nextMulti( BASEITEMSERIAL )
{
}
ObjectFactory::~ObjectFactory()
{
	chars.clear();
	multis.clear();
	items.clear();
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	size_t SizeOfObjects( ObjectType toCount )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	Returns the size of memory allocated to given object type
//o-----------------------------------------------------------------------------------------------o
size_t ObjectFactory::SizeOfObjects( ObjectType toCount )
{
	size_t toRet = 0;
	switch( toCount )
	{
		default:
			break;
		case OT_ITEM:
		case OT_SPAWNER:
			toRet = items.size() * sizeof( CItem );
			break;
		case OT_MULTI:
		case OT_BOAT:
			toRet = multis.size() * sizeof( CMultiObj );
			break;
		case OT_CHAR:
			toRet = chars.size() * sizeof( CChar );
			break;
	}
	return toRet;
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	size_t CountOfObjects( ObjectType toCount )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	Returns the amount of objects that exist of a given object type
//o-----------------------------------------------------------------------------------------------o
UI32 ObjectFactory::CountOfObjects( ObjectType toCount )
{
	UI32 toRet = 0;
	switch( toCount )
	{
		default:
			break;
		case OT_ITEM:
		case OT_SPAWNER:
			toRet = static_cast<UI32>(items.size());
			break;
		case OT_MULTI:
		case OT_BOAT:
			toRet = static_cast<UI32>(multis.size());
			break;
		case OT_CHAR:
			toRet = static_cast<UI32>(chars.size());
			break;
	}
	return toRet;
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	SERIAL ObjectFactory::NextFreeSerial( ObjectType toFind )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	Finds the next free serial to use when creating an object of a given type
//|
//|	Notes		-	Later on we will track in depth, but this allows us
//|					to keep an eye on the serials in use, and make sure
//|					that we assign them correctly
//|
//|					For the moment, we'll keep items and chars under a simple system, though
//|					long term we probably want to break it out
//o-----------------------------------------------------------------------------------------------o
SERIAL ObjectFactory::NextFreeSerial( ObjectType toFind )
{
	SERIAL toRet = INVALIDSERIAL;
	switch( toFind )
	{
		default:
			break;
		case OT_ITEM:
		case OT_MULTI:
		case OT_BOAT:
		case OT_SPAWNER:
			toRet = nextItem++;
			break;
		case OT_CHAR:
			toRet = nextNPC++;
			break;
	}
	return toRet;
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	CBaseObject *CreateObject( ObjectType createType )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	Create a new object with a serial number, and return it back to the creator
//|					From DFNs, or a PC, by and large.
//o-----------------------------------------------------------------------------------------------o
CBaseObject *ObjectFactory::CreateObject( ObjectType createType )
{
	CBaseObject *created = nullptr;
	switch( createType )
	{
		default:													break;
		case OT_ITEM:			created	= new CItem();				break;
		case OT_MULTI:			created	= new CMultiObj();			break;
		case OT_BOAT:			created	= new CBoatObj();			break;
		case OT_SPAWNER:		created	= new CSpawnItem();			break;
		case OT_CHAR:			created	= new CChar();				break;
	}
	// assign serial here
	if( created != nullptr )
		created->SetSerial( NextFreeSerial( createType ) );	// SetSerial() will register our object -

	return created;
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	CBaseObject *CreateBlankObject( ObjectType createType )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	Create a new blank object without a serial number. Serial will be provided
//|					when loading object from worldfiles
//o-----------------------------------------------------------------------------------------------o
CBaseObject *ObjectFactory::CreateBlankObject( ObjectType createType )
{
	CBaseObject *created = nullptr;
	switch( createType )
	{
		default:													break;
		case OT_ITEM:			created	= new CItem();				break;
		case OT_MULTI:			created	= new CMultiObj();			break;
		case OT_BOAT:			created	= new CBoatObj();			break;
		case OT_SPAWNER:		created	= new CSpawnItem();			break;
		case OT_CHAR:			created	= new CChar();				break;
	}
	return created;
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	CBaseObject *FindObject( SERIAL toFind )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	Calculate item, multi or character object from provided serial
//o-----------------------------------------------------------------------------------------------o
CBaseObject *ObjectFactory::FindObject( SERIAL toFind )
{
	OBJECTMAP_ITERATOR fIter, fUpper, fEnd;
	CBaseObject	*	retVal		= nullptr;
	SERIAL			hashValue	= HashSerial( toFind );
	if( toFind != INVALIDSERIAL )
	{
		if( toFind >= BASEITEMSERIAL )	// either an item or multi
		{
			fIter	= items.find( hashValue );
			fUpper	= items.upper_bound( hashValue );
			fEnd	= items.end();
			while( fIter != fUpper && fIter != fEnd )
			{
				if( fIter->second->GetSerial() == toFind )	// is this our object?
				{
					retVal = fIter->second;
					break;
				}
				else
					++fIter;
			}
			if( retVal == nullptr )	// Not an item!  Let's check multis
			{
				fIter	= multis.find( hashValue );
				fUpper	= multis.upper_bound( hashValue );
				fEnd	= multis.end();
				while( fIter != fUpper && fIter != fEnd )
				{
					if( fIter->second->GetSerial() == toFind )	// is this our object?
					{
						retVal = fIter->second;
						break;
					}
					else
						++fIter;
				}
			}
		}
		else	// a character of some sort
		{
			fIter	= chars.find( hashValue );
			fUpper	= chars.upper_bound( hashValue );
			fEnd	= chars.end();
			while( fIter != fUpper && fIter != fEnd )
			{
				if( fIter->second->GetSerial() == toFind )	// is this our object?
				{
					retVal = fIter->second;
					break;
				}
				else
					++fIter;
			}
		}
	}
	return retVal;
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	bool DestroyObject( CBaseObject *toDestroy )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	This function unregisters the object and destroys it from memory.
//|					Essentially, it's either a server shutdown or the object has been deleted,
//|					and is no longer part of the world.
//o-----------------------------------------------------------------------------------------------o
bool ObjectFactory::DestroyObject( CBaseObject *toDestroy )
{
	assert( toDestroy != nullptr );
	UnregisterObject( toDestroy );
	delete toDestroy;
	toDestroy = nullptr;
	return true;
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	bool RegisterObject( CBaseObject *toRegister )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	We want to register an object with the world, that previously
//|					does not exist in our containers
//o-----------------------------------------------------------------------------------------------o
bool ObjectFactory::RegisterObject( CBaseObject *toRegister )
{
	assert( toRegister != nullptr );
	return RegisterObject( toRegister, toRegister->GetSerial() );
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	bool RegisterObject( CBaseObject *toRegister, SERIAL toAttach )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	This allows us to register our object with it's attached serial number
//|
//|					Note that we do not check if this object existed previously, so if you
//|					want to change an object's serial, you would have to Unregister it
//|					and then Register it with the new serial. HOWEVER, that does not guarantee
//|					valid serial numbers and that it's not a duplicate! By and large, we don't
//|					want to call this from anywhere but a world loading routine.
//o-----------------------------------------------------------------------------------------------o
bool ObjectFactory::RegisterObject( CBaseObject *toRegister, SERIAL toAttach )
{
	assert( toRegister != nullptr );
	ObjectType reg = toRegister->GetObjType();
	switch( reg )
	{
		default:
			break;
		case OT_MULTI:
		case OT_BOAT:
			if( toAttach >= nextItem )
				nextItem = toAttach + 1;
			multis.insert( std::make_pair( HashSerial( toAttach ), toRegister ) );
			break;
		case OT_ITEM:
		case OT_SPAWNER:
			if( toAttach >= nextItem )
				nextItem = toAttach + 1;
			items.insert( std::make_pair( HashSerial( toAttach ), toRegister ) );
			break;
		case OT_CHAR:
			if( toAttach >= nextNPC )
				nextNPC = toAttach + 1;
			chars.insert( std::make_pair( HashSerial( toAttach ), toRegister ) );
			break;
	}
	return true;
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	bool UnregisterObject( CBaseObject *toRemove )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	We're done with an object, or want to detach it from the world
//|					This function allows us to detach it, but not destroy it
//|					in case we want to attach it elsewise
//o-----------------------------------------------------------------------------------------------o
bool ObjectFactory::UnregisterObject( CBaseObject *toRemove )
{
	assert( toRemove != nullptr );
	OBJECTMAP_ITERATOR rIter, rUpper, rEnd;
	SERIAL hashValue = HashSerial( toRemove->GetSerial() );
	switch( toRemove->GetObjType() )
	{
		default:
			throw new std::runtime_error( "Damn, bad bad work here!" );
			break;
		case OT_MULTI:
		case OT_BOAT:
			rIter	= multis.find( hashValue );
			rUpper	= multis.upper_bound( hashValue );
			rEnd	= multis.end();
			break;
		case OT_ITEM:
		case OT_SPAWNER:
			rIter	= items.find( hashValue );
			rUpper	= items.upper_bound( hashValue );
			rEnd	= items.end();
			break;
		case OT_CHAR:
			rIter	= chars.find( hashValue );
			rUpper	= chars.upper_bound( hashValue );
			rEnd	= chars.end();
			break;
	}
	while( rIter != rUpper && rIter != rEnd )
	{
		if( rIter->second == toRemove )	// is this our object?
		{
			// let's remove it from the hash table
			switch( toRemove->GetObjType() )
			{
				case OT_MULTI:
				case OT_BOAT:		multis.erase( rIter );	break;
				case OT_ITEM:
				case OT_SPAWNER:	items.erase( rIter );	break;
				case OT_CHAR:		chars.erase( rIter );	break;
				default:
					break;
			}
			break;
		}
		else
			++rIter;
	}
	return true;
}


//o-----------------------------------------------------------------------------------------------o
//|	Function	-	void GarbageCollect( void )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	This is to deal with dead or weird objects, but I don't think
//|					that we would really need it.  No object should be destroyed
//|					except by this object factory anyway.  We may want to do lazy
//|					deletes and only do invalidations.
//o-----------------------------------------------------------------------------------------------o
void ObjectFactory::GarbageCollect( void )
{
	// We may not even need to do anything here, really
}

//o-----------------------------------------------------------------------------------------------o
//|	Function	-	UI32 IterateOver( ObjectType toIterOver, UI32 &b, void *extraData, OBJFUNCTOR( text ) )
//o-----------------------------------------------------------------------------------------------o
//|	Purpose		-	Iterate over all objects of a specified object type
//o-----------------------------------------------------------------------------------------------o
UI32 ObjectFactory::IterateOver( ObjectType toIterOver, UI32 &b, void *extraData, OBJFUNCTOR( text ) )
{
	OBJECTMAP_ITERATOR mBegin, mEnd;
	switch( toIterOver )
	{
		case OT_MULTI:
		case OT_BOAT:
		{
			mBegin	= multis.begin();
			mEnd	= multis.end();
		}
			break;
		case OT_ITEM:
		case OT_SPAWNER:
		{
			mBegin	= items.begin();
			mEnd	= items.end();
		}
			break;
		case OT_CHAR:
		{
			mBegin	= chars.begin();
			mEnd	= chars.end();
		}
			break;
		default:
			return 0xFFFFFFFF;
	}
	bool stillContinue = true;
	while( mBegin != mEnd && stillContinue )
	{
		stillContinue = (*text)(mBegin->second, b, extraData );
		++mBegin;
	}
	return 0;
}