package graph;

/**
 * Abstract class representing an edge in a graph.
 */
public abstract class Edge {

    // ATTRIBUTES

    /** The name of the edge. */
    private String name;

    /** The source vertex of the edge. */
    private Vertex source;

    /** The destination vertex of the edge. */
    private Vertex destination;

    // CONSTRUCTORS

    /**
     * Default constructor initializes the edge with empty name and null source and destination vertices.
     */
    public Edge() {
        this.name = "";
        this.source = null;
        this.destination = null;
    }

    /**
     * Constructor initializes the edge with a specified name, source, and destination vertices.
     *
     * @param s The name of the edge.
     * @param n1 The source vertex of the edge.
     * @param n2 The destination vertex of the edge.
     */
    public Edge(String s, Vertex n1, Vertex n2) {
        this.name = s;
        this.source = n1;
        this.destination = n2;
    }

    // GETTERS

    /**
     * Retrieves the name of the edge.
     *
     * @return The name of the edge.
     */
    public String getName() {
        return this.name;
    }

    /**
     * Retrieves the source vertex of the edge.
     *
     * @return The source vertex of the edge.
     */
    public Vertex getSource() {
        return this.source;
    }

    /**
     * Retrieves the destination vertex of the edge.
     *
     * @return The destination vertex of the edge.
     */
    public Vertex getDestination() {
        return this.destination;
    }

    /**
     * Abstract method to retrieve the screen representation of the edge for visualization.
     *
     * @return The visualizationElements.Edge representing the screen edge.
     */
    public abstract visualizationElements.Edge getScreenEdge();

    // SETTERS

    /**
     * Sets the name of the edge.
     *
     * @param s The name to set for the edge.
     */
    public void setName(String s) {
        this.name = s;
    }

    /**
     * Sets the source vertex of the edge.
     *
     * @param n The source vertex to set for the edge.
     */
    public void setSource(Vertex n) {
        this.source = n;
    }

    /**
     * Sets the destination vertex of the edge.
     *
     * @param n The destination vertex to set for the edge.
     */
    public void setDestination(Vertex n) {
        this.destination = n;
    }
}