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An Embedded Domain Specific Language Parser Generator PLugin compiler

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package net.ericaro.diezel.core.parser;

import java.io.IOException;
import java.util.Deque;

/**
 * Diezel parser delegates almost any call to this class. It is in charge to build the graph, and then return a GuiderGenerator fully configured.
 * 
 * @author eric
 */
public class GraphBuilder implements DiezelSax {


	private Graph graph;
	
	/**
	 * build a raw graph based on a single expression
	 * 
	 * @param expression
	 * @return
	 * @throws ParseException
	 */
	public static Graph build(String expression) throws ParseException {
		GraphBuilder db = new GraphBuilder();
		RegExp.parse(expression, db);
		return db.getGraph();
	}

	
	
	/** utility to generate an expression into a dot file.
	 * @param expression
	 * @param name
	 * @throws ParseException
	 * @throws IOException
	 */
	public static void toFile(String expression, String name) throws ParseException, IOException {
		GraphBuilder db = new GraphBuilder();
		RegExp.parse(expression, db);
		Graph g = db.getGraph();
		g.graph(name);
	}


	/**
	 * to retrieve a graph after the first parsing
	 * 
	 * @return
	 */
	public Graph getGraph() {
		return graph;
	}

	// SAX IMPLEMENTATION FOLLOWS

	public void flow(Graph g) {
		Graph.log(g, "post-definition");
		g.reduce();
		Graph.log(g, "post-reduce");
		g.unimplicit();
		Graph.log(g, "post-unimplicit");
		g.unDuplicate() ;
		Graph.log(g, "post-unduplicate");
		this.graph = g;
	}

	public Graph bang(Deque v) {
		return Graph.bang((Graph[]) v.toArray(new Graph[] {}));
	}

	public Graph opt(Graph v) {
		return Graph.opt(v);
	}

	public Graph plus(Graph v) {
		return Graph.iter_once(v);
	}

	public Graph sel(Graph v1, Graph v2) {
		return Graph.sel(v1, v2);
	}

	public Graph seq(Graph v1, Graph v2) {
		return Graph.seq(v1, v2);
	}

	public Graph star(Graph v) {
		return Graph.iter(v);
	}

	public Graph terminal(String name) {
		return Graph.term(name);
	}

}