package net.abhinavsarkar.algorist;

import guru.nidi.graphviz.engine.Format;
import guru.nidi.graphviz.engine.Graphviz;
import static guru.nidi.graphviz.model.Factory.mutGraph;
import static guru.nidi.graphviz.model.Factory.mutNode;
import guru.nidi.graphviz.model.MutableGraph;
import guru.nidi.graphviz.model.MutableNode;
import java.io.File;
import java.io.IOException;

public class TreeGraphvizVisitor implements AVLTree.Visitor, BinarySearchTree.Visitor
{
    private final MutableGraph graph;
    private final AVLTree<String, MutableNode> index = new AVLTree<>(true);

    public TreeGraphvizVisitor(String graphName)
    {
        this.graph = mutGraph(graphName).setDirected(true);
    }

    @Override
    public void visitNode(String nodeName)
    {
        MutableNode gNode = mutNode(nodeName);
        graph.add(gNode);
        index.insert(nodeName, gNode);
    }

    @Override
    public void visitLink(String parentNodeName, String childNodeName)
    {
        index.get(parentNodeName)
                .ifPresent(gNode -> graph.add(gNode.addLink(mutNode(childNodeName))));
    }

    public void renderToPNG(String fileName) throws IOException
    {
        Graphviz.fromGraph(graph).height(1000).render(Format.PNG).toFile(new File(fileName));
    }
}