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package lapr.project.utils;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import lapr.project.model.Stand;


/**
 *
 * @author UndefinedGadget
 */
public class Kruskal {

    public Kruskal() {
    }

    private Graph graph;
    private int numberVertex;
    private List<Edge>edgesSorted  = new ArrayList<>();
    private List<String> vertex = new ArrayList<>();

    public void initialize() {
        graph = new Graph();
        Stand A = new Stand(10, "A");
        Stand B = new Stand(20, "B");
        Stand C = new Stand(30, "C");
        Stand D = new Stand(40, "D");
        Stand E = new Stand(50, "E");
        Stand F = new Stand(60, "F");
        Stand G = new Stand(70, "G");
        Stand H = new Stand(80, "H");
        Stand I = new Stand(90, "I");

        graph.addEdge(new Edge(B, C, 5));
        graph.addEdge(new Edge(E, G, 6));
        graph.addEdge(new Edge(A, C, 7));
        graph.addEdge(new Edge(C, D, 7));
        graph.addEdge(new Edge(F, H, 8));
        graph.addEdge(new Edge(C, E, 9));
        graph.addEdge(new Edge(A, B, 9));
        graph.addEdge(new Edge(B, E, 10));
        graph.addEdge(new Edge(D, F, 10));
        graph.addEdge(new Edge(A, D, 12));
        graph.addEdge(new Edge(E, F, 12));
        graph.addEdge(new Edge(C, F, 13));
        graph.addEdge(new Edge(H, I, 15));
        graph.addEdge(new Edge(G, H, 16));
        graph.addEdge(new Edge(G, I, 17));
        graph.addEdge(new Edge(B, G, 18));
        graph.addEdge(new Edge(E, I, 18));
        graph.addEdge(new Edge(D, H, 20));
        graph.addEdge(new Edge(F, I, 20));

//        graph.addEdge(new Edge(A, B, 10));
//        graph.addEdge(new Edge(A, C, 12));
//        graph.addEdge(new Edge(A, E, 15));
//        graph.addEdge(new Edge(B, D, 1));
//        graph.addEdge(new Edge(B, E, 5));
//        graph.addEdge(new Edge(C, E, 2));
//        graph.addEdge(new Edge(C, F, 3));
//        graph.addEdge(new Edge(D, E, 3));
//        graph.addEdge(new Edge(D, G, 8));
//        graph.addEdge(new Edge(E, G, 11));
//        graph.addEdge(new Edge(E, H, 6));
//        graph.addEdge(new Edge(E, F, 5));
//        graph.addEdge(new Edge(F, H, 4));
//        graph.addEdge(new Edge(G, H, 10));
//        graph.addEdge(new Edge(H, I, 9));
//        graph.addEdge(new Edge(G, I, 7));

        String sort = "";
        edgesSorted = graph.getEdges();
        Collections.sort(edgesSorted, edgesCriteria);
        for (Edge e : edgesSorted) {
            sort = sort + "(" + e.getInitialVertex().getDescription() + ", " + e.getEndVertex().getDescription() + "), ";
        }
        System.out.println("Edges sorted: " + sort);

        countVertex();
        System.out.println("Number of vertices: " + numberVertex);

        calculateMinimumCable();
    }

    Comparator<Edge> edgesCriteria =(Edge o1, Edge o2) -> {
        if (o1.getDistance() > o2.getDistance()) {
            return 1;
        } else {
            if (o1.getDistance() < o2.getDistance()) {
                return -1;
            } else {
                return 0;
            }
        }
    };

    public void calculateMinimumCable() {
        String ttt = "";
        double totalDistance = 0;
        String tree = "";
        List<String> vertexCopy = new ArrayList<>(vertex);
        for (int a = 0; a < edgesSorted.size(); a++) {
            String start = edgesSorted.get(a).getInitialVertex().getDescription();
            String end = edgesSorted.get(a).getEndVertex().getDescription();
            for (int i = 0; i < vertex.size(); i++) {
                if (vertex.get(i).contains(start)&& !vertex.get(i).contains(end) ) {
                    String aux = "";
                    for (int j = 0; j < vertex.size() - 1; j++) {
                        if (vertex.get(j).contains(end)) {
                            aux = vertex.get(j);
                            vertexCopy.remove(aux);
                            System.out.println("(" + edgesSorted.get(a).getInitialVertex().getDescription() + ", " + edgesSorted.get(a).getEndVertex().getDescription() + ")");
                            tree = tree + "(" + edgesSorted.get(a).getInitialVertex().getDescription() + ", " + edgesSorted.get(a).getEndVertex().getDescription() + "), ";
                            totalDistance = totalDistance + edgesSorted.get(a).getDistance();
                        }
                    }
                    try {
                    String temp = vertex.get(i) + aux;
                    vertexCopy.set(i,temp);
                    vertexCopy.remove(end);
                    } catch (IndexOutOfBoundsException e) {
                        System.out.println("Tree: " + tree);
                        System.out.println("Total Distance = " + totalDistance + "m");
                    }
                }
            }
            for (String v : vertex) {
                ttt = ttt + v + " ";
            }
            System.out.println(ttt);
            ttt = "";
            vertex = vertexCopy;
        }
        System.out.println("Tree: " + tree);
        System.out.println("Total Distance = " + totalDistance + "m");
    }

    public void countVertex() {
        edgesSorted.stream().map((e) -> {
            if (!vertex.contains(e.getInitialVertex().getDescription())) {
                vertex.add(e.getInitialVertex().getDescription());
            }
            return e;
        }).filter((e) -> (!vertex.contains(e.getEndVertex().getDescription()))).forEachOrdered((e) -> {
            vertex.add(e.getEndVertex().getDescription());
        });
        numberVertex = vertex.size();
    }




}






OUTPUT:

Edges sorted: (B, C), (E, G), (A, C), (C, D), (F, H), (C, E), (A, B), (B, E), (D, F), (A, D), (E, F), (C, F), (H, I), (G, H), (G, I), (B, G), (E, I), (D, H), (F, I),
Number of vertices: 9
(B, C)
B C E G A D F H I
(E, G)
BC EG A D F H I
(A, C)
EG A DBC F H I
EG A DBC F H I
(F, H)
EG A DBC FH I
(C, E)
A DBC FHEG I
(A, B)
ADBC FHEG I
(B, E)
ADBCFHEG I
ADBCFHEG I
ADBCFHEG I
ADBCFHEG I
ADBCFHEG I
ADBCFHEG
ADBCFHEG
ADBCFHEG
ADBCFHEG
ADBCFHEG
ADBCFHEG
ADBCFHEG
Tree: (B, C), (E, G), (A, C), (F, H), (C, E), (A, B), (B, E),
Total Distance = 54.0m