Main.java

package graphvisualizer.graphalgorithms;

import graphvisualizer.containers.MenuPane;
import graphvisualizer.graph.Vertex;
import graphvisualizer.graphview.*;
import graphvisualizer.graph.Graph;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.stage.Stage;
import javafx.stage.StageStyle;
import graphvisualizer.containers.SmartGraphDemoContainer;
import graphvisualizer.graph.AdjacencyMapDigraph;

import java.util.LinkedList;
import java.util.Queue;

public class Main extends Application {
    private static int selectedVerticesCount = 0;
    private static Vertex<String> startVertex;
    private static Vertex<String> endVertex;

    @Override
    public void start(Stage ignored) {
        final AdjacencyMapDigraph<String, Integer> defaultDigraph = new AdjacencyMapDigraph<>();
        createDefaultDigraph(defaultDigraph);
        SmartPlacementStrategy strategy = new SmartCircularSortedPlacementStrategy();
        SmartGraphPanel<String, Integer> graphView = new SmartGraphPanel<>(defaultDigraph, strategy);
        SmartGraphDemoContainer smartGraphDemoContainer = new SmartGraphDemoContainer(graphView);
        MenuPane menu = smartGraphDemoContainer.getMenu();
        final Queue<String> addedVertices = new LinkedList<>();
        createAddedVertices(addedVertices);

        Scene scene = new Scene(smartGraphDemoContainer, 1024, 768);
        Stage stage = new Stage(StageStyle.DECORATED);
        stage.setOpacity(0.0);
        stage.setTitle("Graph Algorithms Visualization");
        stage.setScene(scene);
        stage.setMaximized(true);
        stage.show();
        stage.setOpacity(1.0);
        graphView.init();
        graphView.setAutomaticLayout(true);

        menu.getStatusBox().setText("[Graph Algorithms Visualization]\n1. Click the buttons above to start the graph algorithms.\n" +
                "2. Double click to select the vertices and the edges.\n3. Click \"ADD VERTEX\" to add up to 5 additional vertices.\n" +
                "4. Click \"RESET\" to reset the default graph.\n\n" + defaultDigraph);

        graphView.setVertexDoubleClickAction(graphVertex -> {
            switch (selectedVerticesCount) {
                case 0:
                    for (Vertex<String> vertex : defaultDigraph.vertices()) {
                        graphView.getStylableVertex(vertex).setStyleClass("vertex");
                    }
                    startVertex = graphVertex.getUnderlyingVertex();
                    graphVertex.setStyleClass("selectedVertex");
                    ++selectedVerticesCount;
                    menu.getStatusBox().appendText(graphVertex.getUnderlyingVertex() + " is selected as starting vertex.\n\n");
                    break;

                case 1:
                    if(!graphVertex.getUnderlyingVertex().equals(startVertex)) {
                        endVertex = graphVertex.getUnderlyingVertex();
                        graphVertex.setStyleClass("selectedVertex");
                        ++selectedVerticesCount;
                        menu.getStatusBox().appendText(graphVertex.getUnderlyingVertex() + " is selected as ending vertex.\n\n");
                    }
                    break;

                case 2:
                    if(!graphVertex.getUnderlyingVertex().equals(startVertex) && !graphVertex.getUnderlyingVertex().equals(endVertex)) {
                        graphView.getStylableVertex(startVertex).setStyleClass("vertex");
                        startVertex = endVertex;
                        endVertex = graphVertex.getUnderlyingVertex();
                        graphVertex.setStyleClass("selectedVertex");
                        menu.getStatusBox().appendText(startVertex + " is selected as new starting vertex.\n\n");
                        menu.getStatusBox().appendText(endVertex + " is selected as new ending vertex.\n\n");
                    }
                default:
            }
        });

        graphView.setEdgeDoubleClickAction(graphEdge -> menu.getStatusBox().appendText(graphEdge.getUnderlyingEdge() + " is selected.\n\n"));

        menu.setStrongConnectivityButtonAction(event -> {
            for (Vertex<String> vertex : defaultDigraph.vertices()) {
                graphView.getStylableVertex(vertex).setStyleClass("vertex");
            }
            menu.getStatusBox().appendText(StrongConnectivity.start(defaultDigraph, graphView));
            selectedVerticesCount = 0;
            startVertex = endVertex = null;
        });

        menu.setCycleDetectionButtonAction(event -> {
            for (Vertex<String> vertex : defaultDigraph.vertices()) {
                graphView.getStylableVertex(vertex).setStyleClass("vertex");
            }
            menu.getStatusBox().appendText(CycleDetection.start(defaultDigraph, graphView));
            selectedVerticesCount = 0;
            startVertex = endVertex = null;
        });

        menu.setShortestPathButtonAction(event -> {
            if(startVertex != null && endVertex != null) {
                menu.getStatusBox().appendText(ShortestPath.start(defaultDigraph, graphView, startVertex, endVertex));
                selectedVerticesCount = 0;
                startVertex = endVertex = null;
            }
            else{
                menu.getStatusBox().appendText("Please select two vertices to compute the shortest path between them.\n\n");
            }
        });

        menu.setAddVertexButtonAction(event -> {
            if (!addedVertices.isEmpty()) {
                String addedVertex = addedVertices.remove();
                defaultDigraph.insertVertex(addedVertex);
                graphView.update();
                menu.getStatusBox().appendText("Vertex{" + addedVertex + "} has been added.\n\n");
            }
            else {
                menu.getStatusBox().appendText("No additional vertices will be added.\n\n");
            }
        });

        menu.setResetButtonAction(event -> {
            resetDefaultDigraph(defaultDigraph, graphView);
            createAddedVertices(addedVertices);
            selectedVerticesCount = 0;
            startVertex = endVertex = null;
            menu.getStatusBox().appendText("Graph has been reset.\n\n" + defaultDigraph);
        });
    }

    public static void main(String[] args) {
        launch(args);
    }

    private void createDefaultDigraph(Graph<String, Integer> defaultDigraph) {
        defaultDigraph.insertVertex("AU");
        defaultDigraph.insertVertex("BE");
        defaultDigraph.insertVertex("DK");
        defaultDigraph.insertVertex("EG");
        defaultDigraph.insertVertex("HK");
        defaultDigraph.insertEdge("AU", "HK", 6);
        defaultDigraph.insertEdge("AU", "EG", 12);
        defaultDigraph.insertEdge("DK", "BE", 1);
        defaultDigraph.insertEdge("DK", "EG", 4);
        defaultDigraph.insertEdge("HK", "BE", 9);
    }

    private void resetDefaultDigraph(Graph<String, Integer> defaultDigraph, SmartGraphPanel<String, Integer> graphView) {
        ((AdjacencyMapDigraph<String, Integer>) defaultDigraph).clear();
        graphView.getStylableVertex(defaultDigraph.insertVertex("AU")).setStyleClass("vertex");
        graphView.getStylableVertex(defaultDigraph.insertVertex("BE")).setStyleClass("vertex");
        graphView.getStylableVertex(defaultDigraph.insertVertex("DK")).setStyleClass("vertex");
        graphView.getStylableVertex(defaultDigraph.insertVertex("EG")).setStyleClass("vertex");
        graphView.getStylableVertex(defaultDigraph.insertVertex("HK")).setStyleClass("vertex");
        defaultDigraph.insertEdge("AU", "HK", 6);
        defaultDigraph.insertEdge("AU", "EG", 12);
        defaultDigraph.insertEdge("DK", "BE", 1);
        defaultDigraph.insertEdge("DK", "EG", 4);
        defaultDigraph.insertEdge("HK", "BE", 9);
        graphView.update();
    }

    private void createAddedVertices(Queue<String> addVertices) {
        addVertices.clear();
        addVertices.add("JS");
        addVertices.add("MN");
        addVertices.add("PQ");
        addVertices.add("WX");
        addVertices.add("YZ");
    }
}