///////////////////////////////////////////////////////////////////////////////
//
// Name:		UnitManager.cpp
// Author:		Rich Cross
// Contact:		rich@wildfiregames.com
//
///////////////////////////////////////////////////////////////////////////////

#include "precompiled.h"

#include <float.h>

#include "lib/res/res.h"
#include "Model.h"
#include "UnitManager.h"
#include "Unit.h"
#include "ps/CConsole.h"
#include "ObjectManager.h"
#include "ObjectEntry.h"
#include "simulation/Entity.h"
#include "simulation/LOSManager.h"
#include "simulation/TerritoryManager.h"

extern CConsole* g_Console;

#include <algorithm>

///////////////////////////////////////////////////////////////////////////////
// CUnitManager constructor
CUnitManager::CUnitManager()
: m_NextID(0)
{
}

///////////////////////////////////////////////////////////////////////////////
// CUnitManager destructor
CUnitManager::~CUnitManager()
{
	DeleteAll();
}


///////////////////////////////////////////////////////////////////////////////
// AddUnit: add given unit to world
void CUnitManager::AddUnit(CUnit* unit)
{
	m_Units.push_back(unit);
}

///////////////////////////////////////////////////////////////////////////////
// RemoveUnit: remove given unit from world, but don't delete it
void CUnitManager::RemoveUnit(CUnit* unit)
{
	// find entry in list
	typedef std::vector<CUnit*>::iterator Iter;
	Iter i=std::find(m_Units.begin(),m_Units.end(),unit);
	if (i!=m_Units.end()) {
		m_Units.erase(i);
	}
}

///////////////////////////////////////////////////////////////////////////////
// DeleteUnit: remove given unit from world and delete it
void CUnitManager::DeleteUnit(CUnit* unit)
{
	RemoveUnit(unit);
	delete unit;
}

///////////////////////////////////////////////////////////////////////////////
// DeleteAll: remove and delete all units
void CUnitManager::DeleteAll()
{
	uint i;
	for (i=0;i<m_Units.size();i++) {
		delete m_Units[i];
	}
	m_Units.clear();
}


///////////////////////////////////////////////////////////////////////////////
// PickUnit: iterate through units testing given ray against bounds of each 
// unit; return the closest unit, or null if everything missed
CUnit* CUnitManager::PickUnit(const CVector3D& origin, const CVector3D& dir) const
{
	CLOSManager* losMgr = g_Game->GetWorld()->GetLOSManager();

	// closest object found so far
	CUnit* hit = 0;
	// distance to closest object found so far
	float dist = FLT_MAX;
	// closest approach offset (easier to pick small stuff in forests than standard ScEd style selection)
	float minrel = FLT_MAX;

	for (uint i=0; i<m_Units.size(); i++) {
		CUnit* unit = m_Units[i];
		float tmin, tmax;
		
		CEntity* ent = unit->GetEntity();
		if( ent && !ent->m_visible )
			continue;
		
		if (unit->GetModel()->GetBounds().RayIntersect(origin, dir, tmin, tmax)
			&& losMgr->GetUnitStatus(unit, g_Game->GetLocalPlayer()) != UNIT_HIDDEN)
		{
			// Point of closest approach
			CVector3D obj;
			unit->GetModel()->GetBounds().GetCentre(obj);
			CVector3D delta = obj - origin;
			float distance = delta.Dot(dir);
			CVector3D closest = origin + dir * distance;
			CVector3D offset = obj - closest;

			float rel = offset.GetLength();
			if (rel < minrel) {
				hit = unit;
				dist = tmin;
				minrel = rel;
			}
		}
	}
	return hit;
}

///////////////////////////////////////////////////////////////////////////////
// CreateUnit: create a new unit and add it to the world
CUnit* CUnitManager::CreateUnit(const CStr& actorName, CEntity* entity, const std::set<CStr8>& selections)
{
	CObjectBase* base = g_ObjMan.FindObjectBase(actorName);

	if (! base)
		return NULL;

	std::set<CStr8> actorSelections = base->CalculateRandomVariation(selections);

	std::vector<std::set<CStr8> > selectionsVec;
	selectionsVec.push_back(actorSelections);

	CObjectEntry* obj = g_ObjMan.FindObjectVariation(base, selectionsVec);

	if (! obj)
		return NULL;

	CUnit* unit = new CUnit(obj, entity, actorSelections);
	AddUnit(unit);
	return unit;
}

///////////////////////////////////////////////////////////////////////////////
// FindByID
CUnit* CUnitManager::FindByID(int id) const
{
	if (id < 0)
		return NULL;

	for (size_t i = 0; i < m_Units.size(); ++i)
		if (m_Units[i]->GetID() == id)
			return m_Units[i];

	return NULL;
}