/*
 public Graph API

 constructors:
   public Graph()

 mutators:
   public boolean addNode(Node) returns false iff can't add node to graph
   public boolean addEdge(Edge) returns false iff can't add edge to graph

 accessors:
   public NodeSet getNodeSet()
   public EdgeSet getEdgeSet()

 misc:
   public int nodeCount()
   public int edgeCount()
   public EdgeSet outgoingEdges(Node node) returns an array of the node's outgoing edges

*/

public class Graph {
    private NodeSet nodeSet;
    private EdgeSet edgeSet;

    public int nodeCount() {
		return nodeSet.length();
	}

    public int edgeCount() {
		return edgeSet.length();
	}

    public Graph() {
		nodeSet = new NodeSet( );
		edgeSet = new EdgeSet( );
    }

    public void addNode(Node node) {
        nodeSet.addNode(node);
    }

    public void addEdge(Edge edge) {
		edgeSet.addEdge(edge);
		addNode(edge.getSourceNode());
		addNode(edge.getTargetNode());
    }

    public EdgeSet getOutgoingEdges(Node node) {
		EdgeSet outEdges = new EdgeSet();

		for(int i = 0; i < edgeSet.length(); i++) {
			if (node.equals(edgeSet.getEdge(i).getSourceNode())) {
				outEdges.addEdge(edgeSet.getEdge(i));
			}
		}
		return outEdges;
    }

    public NodeSet getNodeSet() {
		return(nodeSet);
    }

    public EdgeSet getEdgeSet() {
		return(edgeSet);
    }
}