#pragma once
#include <vector>
#include <assert.h>
#include "../../core/CollectionHelper.h"
#include "../../inc/tbb/parallel_for.h"

template<typename T>
struct NearestFinder
{
	T operator()(const T& source, const std::vector<T>& values) const
	{
		assert(!values.empty());
		float min = T::Distance(source, values[0]);
		size_t minIndex = 0;
		for (size_t i = 0; i < values.size(); i++)
		{
			float distance = T::Distance(source, values[i]);
			if (distance < min)
			{
				min = distance;
				minIndex = i;
			}
		}
		return values[minIndex];
	}
};

template<typename T>
struct ParallelNearestFinder
{
	T operator()(const T& source, const std::vector<T>& values) const
	{
		assert(!values.empty());
		std::vector<float> distances(values.size());
		tbb::parallel_for(size_t(0), values.size(), [&](size_t i) { distances[i] = T::Distance(source, values[i]); });
		return values[CollectionHelper::MinIndex(distances)];
	}
};