/*******************************************************************************
 * Copyright (c) 2015 Eclipse RDF4J contributors, Aduna, and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Distribution License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *******************************************************************************/
/* Generated By:JavaCC: Do not edit this line. JJTSyntaxTreeBuilderState.java Version 5.0 */
package org.eclipse.rdf4j.query.parser.serql.ast;

public class JJTSyntaxTreeBuilderState {

	private java.util.List<Node> nodes;

	private java.util.List<Integer> marks;

	private int sp; // number of nodes on stack

	private int mk; // current mark

	private boolean node_created;

	public JJTSyntaxTreeBuilderState() {
		nodes = new java.util.ArrayList<>();
		marks = new java.util.ArrayList<>();
		sp = 0;
		mk = 0;
	}

	/*
	 * Determines whether the current node was actually closed and pushed. This should only be called in the final user
	 * action of a node scope.
	 */
	public boolean nodeCreated() {
		return node_created;
	}

	/*
	 * Call this to reinitialize the node stack. It is called automatically by the parser's ReInit() method.
	 */
	public void reset() {
		nodes.clear();
		marks.clear();
		sp = 0;
		mk = 0;
	}

	/*
	 * Returns the root node of the AST. It only makes sense to call this after a successful parse.
	 */
	public Node rootNode() {
		return nodes.get(0);
	}

	/* Pushes a node on to the stack. */
	public void pushNode(Node n) {
		nodes.add(n);
		++sp;
	}

	/*
	 * Returns the node on the top of the stack, and remove it from the stack.
	 */
	public Node popNode() {
		if (--sp < mk) {
			mk = marks.remove(marks.size() - 1);
		}
		return nodes.remove(nodes.size() - 1);
	}

	/* Returns the node currently on the top of the stack. */
	public Node peekNode() {
		return nodes.get(nodes.size() - 1);
	}

	/*
	 * Returns the number of children on the stack in the current node scope.
	 */
	public int nodeArity() {
		return sp - mk;
	}

	public void clearNodeScope(Node n) {
		while (sp > mk) {
			popNode();
		}
		mk = marks.remove(marks.size() - 1);
	}

	public void openNodeScope(Node n) {
		marks.add(mk);
		mk = sp;
		n.jjtOpen();
	}

	/*
	 * A definite node is constructed from a specified number of children. That number of nodes are popped from the
	 * stack and made the children of the definite node. Then the definite node is pushed on to the stack.
	 */
	public void closeNodeScope(Node n, int num) {
		mk = marks.remove(marks.size() - 1);
		while (num-- > 0) {
			Node c = popNode();
			c.jjtSetParent(n);
			n.jjtAddChild(c, num);
		}
		n.jjtClose();
		pushNode(n);
		node_created = true;
	}

	/*
	 * A conditional node is constructed if its condition is true. All the nodes that have been pushed since the node
	 * was opened are made children of the conditional node, which is then pushed on to the stack. If the condition is
	 * false the node is not constructed and they are left on the stack.
	 */
	public void closeNodeScope(Node n, boolean condition) {
		if (condition) {
			int a = nodeArity();
			mk = marks.remove(marks.size() - 1);
			while (a-- > 0) {
				Node c = popNode();
				c.jjtSetParent(n);
				n.jjtAddChild(c, a);
			}
			n.jjtClose();
			pushNode(n);
			node_created = true;
		} else {
			mk = marks.remove(marks.size() - 1);
			node_created = false;
		}
	}
}
/* JavaCC - OriginalChecksum=d31fabe00432249498b2d361c77caf11 (do not edit this line) */
