#include "..\e2dmanager.h"
#include "..\e2dnode.h"
#include "..\e2dtool.h"


e2d::CollisionManager * e2d::CollisionManager::_instance = nullptr;

e2d::CollisionManager * e2d::CollisionManager::getInstance()
{
	if (!_instance)
		_instance = new (std::nothrow) CollisionManager;
	return _instance;
}

void e2d::CollisionManager::destroyInstance()
{
	if (_instance)
	{
		delete _instance;
		_instance = nullptr;
	}
}

e2d::CollisionManager::CollisionManager()
{
}

e2d::CollisionManager::~CollisionManager()
{
}

void e2d::CollisionManager::__addCollider(Collider * collider)
{
	_colliders.push_back(collider);
}

void e2d::CollisionManager::__removeCollider(Collider * collider)
{
	auto iter = std::find(_colliders.begin(), _colliders.end(), collider);
	if (iter != _colliders.end())
	{
		_colliders.erase(iter);
	}
}

void e2d::CollisionManager::__updateCollider(Collider* collider)
{
	if (Game::getInstance()->isPaused() ||
		!Game::getInstance()->getConfig().isCollisionEnabled() ||
		SceneManager::getInstance()->isTransitioning())
		return;

	std::vector<Collider*> currColliders;
	std::copy_if(
		_colliders.begin(),
		_colliders.end(),
		std::back_inserter(currColliders),
		[this, collider](Collider* passive) -> bool
		{
			return collider != passive &&
				passive->getNode()->isVisible() &&
				collider->getNode()->getParentScene() == passive->getNode()->getParentScene() &&
				this->isCollidable(collider->getNode(), passive->getNode());
		}
	);

	for (const auto& passive : currColliders)
	{
		// 判断两碰撞体交集情况
		Collider::Relation relation = collider->getRelationWith(passive);
		// 忽略 UNKNOWN 和 DISJOIN 情况
		if (relation != Collider::Relation::Unknown &&
			relation != Collider::Relation::Disjoin)
		{
			auto activeNode = collider->getNode();
			auto passiveNode = passive->getNode();
			// 触发两次碰撞事件
			Collision activeCollision(passiveNode, relation);
			activeNode->getParentScene()->onCollision(activeCollision);
			activeNode->onCollision(activeCollision);

			Collision passiveCollision(activeNode, passive->getRelationWith(collider));
			passiveNode->getParentScene()->onCollision(passiveCollision);
			passiveNode->onCollision(passiveCollision);
		}
	}
}

void e2d::CollisionManager::addName(const String & name1, const String & name2)
{
	if (!name1.isEmpty() && !name2.isEmpty())
	{
		_collisionList.insert(std::make_pair(name1.getHashCode(), name2.getHashCode()));
	}
}

void e2d::CollisionManager::addName(const std::vector<std::pair<String, String> >& names)
{
	for (const auto& name : names)
	{
		if (!name.first.isEmpty() && !name.second.isEmpty())
		{
			_collisionList.insert(std::make_pair(name.first.getHashCode(), name.second.getHashCode()));
		}
	}
}

bool e2d::CollisionManager::isCollidable(Node * node1, Node * node2)
{
	return CollisionManager::isCollidable(node1->getName(), node2->getName());
}

bool e2d::CollisionManager::isCollidable(const String & name1, const String & name2)
{
	size_t hashName1 = name1.getHashCode(), 
		hashName2 = name2.getHashCode();
	auto pair1 = std::make_pair(hashName1, hashName2), 
		pair2 = std::make_pair(hashName2, hashName1);
	for (const auto& pair : _collisionList)
	{
		if (pair == pair1 || pair == pair2)
		{
			return true;
		}
	}
	return false;
}