package com.aids.graph;

/**
 * Created by spike994 on 08.05.15.
 */

import java.util.LinkedList;
import java.util.List;
import java.util.Random;

public class MatrixGraph implements Graph {

    private int V;
    private int E;
    public boolean[][] adjacencyMatrix;
    private Random rand = new Random();

    /**
     *
     * @param V amount of vertexes
     * @param param density
     */
    public MatrixGraph(int V, double param) {
        this.V = V;
        this.setE((int) (((V * (V - 1)) / 2)*param));
        this.adjacencyMatrix = new boolean[V][V];
        for (int i = 0; i < ((V * (V - 1)) / 2)*param; i++) {
            int v1 = rand.nextInt(V);
            int v2 = rand.nextInt(V);
            if (v1 == v2) {
                i--;
            } else {
                if (!adjacencyMatrix[v1][v2]) {
                    adjacencyMatrix[v1][v2] = true;
                    adjacencyMatrix[v2][v1] = true;
                } else {
                    i--;
                }
            }
        }
    }
    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("\n");
        for (int v = 0; v < V; v++) {
            sb.append("||" + v + "||");
            for (int w = 0; w < V; w++) {
                if (adjacencyMatrix[v][w]) {
                    sb.append(" [1] ");
                } else
                    sb.append(" [0] ");
            }
            sb.append("\n");
        }
        return sb.toString();
    }

    public Integer[] getAdjacentVertexes(int v) {
        LinkedList<Integer> list = new LinkedList<Integer>();
        for (int i = 0; i < V; i++) {
            if (adjacencyMatrix[v][i]) {
                list.add(i);
            }
        }
        return list.toArray(new Integer[1]);
    }

    public ListGraph toListGraph() {
        @SuppressWarnings("unchecked")
        List<Integer>[] adjacencyList = new List[this.V];
        for (int i = 0; i < this.V; i++) {
            adjacencyList[i] = new LinkedList<Integer>();
            for (int j = 0; j < this.V; j++) {
                if (adjacencyMatrix[i][j]){
                    adjacencyList[i].add(j);
                }
            }
        }
        return new ListGraph(this.V, adjacencyList);
    }
    public int getE() {
        return E;
    }
    public void setE(int e) {
        E = e;
    }
    public int getV(){
        return V;
    }
}