using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace k_nearest_neighbors_algorithm
{
    public partial class Form1 : Form
    {
        static List<Tuple<double[], bool>> listOfFruits = new List<Tuple<double[], bool>>();
        static List<double[]> trainingSet = new List<double[]>();

        public Form1()
        {
            InitializeComponent();

            FillListOfFruits();
            Training();
            Test();
        }

        static void FillListOfFruits()
        {
            listOfFruits.Add(new Tuple<double[], bool>(new double[] { 6.6, 35.8, 46.8 }, false));
            listOfFruits.Add(new Tuple<double[], bool>(new double[] { 1.2, 0.1, 8.1 }, true));
            listOfFruits.Add(new Tuple<double[], bool>(new double[] { 14.1, 8.3, 1.2 }, true));
            listOfFruits.Add(new Tuple<double[], bool>(new double[] { 3.4, 30.2, 64.7 }, false));
            listOfFruits.Add(new Tuple<double[], bool>(new double[] { 4.7, 9.3, 84.4 }, false));
            listOfFruits.Add(new Tuple<double[], bool>(new double[] { 1.7, 0, 10.8 }, true));
            listOfFruits.Add(new Tuple<double[], bool>(new double[] { 1.5, 0, 5.3 }, true));
            listOfFruits.Add(new Tuple<double[], bool>(new double[] { 3.1, 67, 2.6 }, false));
        }

        static void Training()
        {
            foreach (var fruit in listOfFruits)
            {
                Fruit f = new Fruit(fruit.Item1[0], fruit.Item1[1], fruit.Item1[2], fruit.Item2);

                trainingSet.Add(f.Method());
            }
        }

        static double EuclideanDistance(double[] a, double[] b)
        {
            double res = 0;
            for (int i = 0; i < a.Length; i++)
            {
                res += Math.Pow(a[i] - b[i], 2);
            }

            return Math.Sqrt(res);
        }

        static List<double> GetListOfDistances(double[] newFruitParams)
        {
            double distance = 0.0;

            List<double> distances = new List<double>();

            for (int i = 0; i < trainingSet.Count; i++)
            {
                distance = EuclideanDistance(newFruitParams, trainingSet[i]);
                distances.Add(distance);
            }

            return distances;
        }

        static List<int> GetIndexesOfNearestNeighbors(List<double> distances, int k)
        {
            List<int> indexes = new List<int>();
            for (int i = 0; i < k; i++)
            {
                int index = distances.IndexOf(distances.Min());
                indexes.Add(index);
                // MessageBox.Show(index.ToString());
                distances[index] = 99999;
            }

            return indexes;
        }

        static List<bool> GetClassesOfNeighbors(List<int> indexesOfNearestNeighbors)
        {
            List<bool> classificators = new List<bool>();
            foreach (var ind in indexesOfNearestNeighbors)
            {
                //MessageBox.Show(listOfFruits[ind].Item2.ToString());
                classificators.Add(listOfFruits[ind].Item2);
            }

            return classificators;
        }

        static bool Classify(List<bool> classificators)
        {
            int health = 0;
            int notHealth = 0;

            foreach(var c in classificators)
            {
                if (c)
                {
                    health++;
                }
                else
                {
                    notHealth++;
                }
            }
            if (health > notHealth)
                return true;
            return false;
        }

        static void Test()
        {
            Fruit newFruit = new Fruit(1.1, 30, 42.6); // создаем экземпляр нового фрукта
            double[] newFruitParams = newFruit.Method(); // переводим его БЖУ в массив

            List<double> distances = GetListOfDistances(newFruitParams);

            int k = 3; // количество соседей

            List<int> indexesOfNearestNeighbors = GetIndexesOfNearestNeighbors(distances, k); // индексы ближайших соседей

            List<bool> classificators = GetClassesOfNeighbors(indexesOfNearestNeighbors);

            bool isHealthy = Classify(classificators);
            MessageBox.Show(isHealthy.ToString());
        }
    }
}