#pragma once
#include <string>
#include <map>
#include <assert.h>

template <typename Resource, typename Identifier>
class ResourceHolder
{
public:

	void load(Identifier id, const std::string& fileName);

	template<typename Parameter>
	void load(Identifier id, const std::string& fileName, const Parameter& secondParam);

	Resource& get(Identifier id);
	const Resource& get(Identifier id) const;

private:

	std::map<Identifier, std::unique_ptr<Resource>> _resourceMap;

};

// Implementation
// ---------------

template <typename Resource, typename Identifier>
void ResourceHolder<Resource, Identifier>::load(Identifier id, const std::string& fileName)
{
	std::unique_ptr<Resource> resource(new Resource());
	if (resource->loadFromFile(fileName) == false)
	{
		throw std::runtime_error("ResourceHolder failed to load" + fileName);
	}

	auto inserted = _resourceMap.insert(
		std::make_pair(id, std::move(resource)));

	assert(inserted.second);
}

template<typename Resource, typename Identifier>
Resource& ResourceHolder<Resource, Identifier>::get(Identifier id)
{
	auto found = _resourceMap.find(id);
	assert(("Could not find resource in map!", found != _resourceMap.end()));
	return *found->second;

}

template<typename Resource, typename Identifier>
const Resource& ResourceHolder<Resource, Identifier>::get(Identifier id) const
{
	auto found = _resourceMap.find(id);
	assert(("Could not find resource in map!", found != _resourceMap.end()));
	return *found->second;

}

template <typename Resource, typename Identifier>
template <typename Parameter>
void ResourceHolder<Resource, Identifier>::load(
	Identifier id,
	const std::string& fileName,
	const Parameter& secondParam)
{
	std::unique_ptr<Resource> resource(new Resource());
	if (resource->loadFromFile(fileName, secondParam))
	{
		throw std::runtime_error("ResourceHolder failed to load" + fileName);
	}

	auto inserted = _resourceMap.insert(
		std::make_pair(id, std::move(resource)));

	assert(inserted.second);
}