/*
 * Copyright 2008 Wishnu Prasetya.
 *
 * This file is part of T2.
 * T2 is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License (GPL) as published by the
 * Free Software Foundation; either version 3 of the License, or any
 * later version.
 * 
 * T2 is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * A copy of the GNU General Public License can be found in T2 distribution.
 * If it is missing, see http://www.gnu.org/licenses.
 */

package t2ext.bcel.utils;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Iterator;

import com.sun.org.apache.bcel.internal.generic.InstructionHandle;
import com.sun.org.apache.bcel.internal.generic.InstructionList;

/**
 * Represents a node in the CFG
 * 
 * @author Maaike Gerritsen
 */
public class Node implements Serializable{
	private static final long serialVersionUID = 1L;
	private int _id;
	private Node _childLeft;
	private InstructionHandle _nodeHandle;
	private InstructionList _listToInsert;
	private ArrayList<Node> _parents;
	private ArrayList<Node> _children;
	private Node _childRight;
	private boolean _isBranchNode;
	private boolean _isRightChild;
	private boolean _listSet;
	private boolean _isLast;
	private boolean _cycleBegin;
	private boolean _cycleEnd;
	private boolean _addToCFG;
	private boolean _targetOfGoto;
	private ArrayList<Integer> _pathIds;
	private int _lineNr;

	public Node() {
		_parents = new ArrayList<Node>();
		_children = new ArrayList<Node>();
		_pathIds = new ArrayList<Integer>();
		_isBranchNode = false;
		_isRightChild = false;
		_listSet = false;
		_isLast = false;
		_cycleBegin = false;
		_cycleEnd = false;
		_addToCFG = false;
		_targetOfGoto = false;
	}

	public int getId() {
		return _id;
	}
	
	public void setLineNr(int lineNr){
		_lineNr = lineNr;
	}
	
	public int getLineNr(){
		return _lineNr;
	}

	public void setId(int id) {
		_id = id;
	}

	public Node getChildLeft() {
		return _childLeft;
	}
	
	public boolean isLast(){
		return _isLast;
	}
	
	public boolean getCycleBegin(){
		return _cycleBegin;
	}
	
	public void setCycleBegin(boolean begin){
		_cycleBegin = begin;
	}
	
	public boolean getCycleEnd(){
		return _cycleEnd;
	}
	
	public void setCycleEnd(boolean end){
		_cycleEnd = end;
	}
	
	public void setIsLast(boolean last){
		_isLast = last;
	}

	public void setNodeHandle(InstructionHandle handle) {
		_nodeHandle = handle;
	}

	public InstructionHandle getNodeHandle() {
		return _nodeHandle;
	}

	public void setChildLeft(Node childLeft) {
		_childLeft = childLeft;
	}

	public ArrayList<Node> getParents() {
		return _parents;
	}

	public void addToParents(Node parent) {
		_parents.add(parent);
	}

	public ArrayList<Node> getChildren() {
		return _children;
	}

	public void addToChildren(Node child) {
		_children.add(child);
	}

	public Node getChildRight() {
		return _childRight;
	}

	public void setChildRight(Node right) {
		_childRight = right;
	}

	public boolean isBranchNode() {
		return _isBranchNode;
	}

	public void setIsBranchNode(boolean branchNode) {
		_isBranchNode = branchNode;
	}

	public boolean isRightChild() {
		return _isRightChild;
	}

	public void setIsRightChild(boolean isRight) {
		_isRightChild = isRight;
	}

	public void setListToInsert(InstructionList list) {
		_listToInsert = list;
	}

	public void addToList(InstructionList list) {
		if (_listToInsert == null)
			setListToInsert(list);
		else if (!_listSet)
			_listToInsert.insert(list);
		_listSet = true;
	}

	public InstructionList getListToInsert() {
		return _listToInsert;
	}

	public boolean hasIfParent() {
		for (Iterator<Node> iterator = _parents.iterator(); iterator.hasNext();) {
			Node parent = iterator.next();
			if (parent.isBranchNode())
				return true;
		}
		return false;
	}
	
	public boolean hasSameLineNrAsParent(){
		for (Iterator<Node> iterator = _parents.iterator(); iterator.hasNext();) {
			Node parent = iterator.next();
			if (parent.isBranchNode() && parent.getLineNr()!=_lineNr){
				return false;
			}
		}
		return true;
	}
	
	public boolean isUnnecessaryNode(){
		if(isBranchNode())
			return false;
		if(!hasIfParent())
			return true;
		if(hasSameLineNrAsParent() && allowAddToCFG())
			return false;
		if(hasSameLineNrAsParent())
			return true;
		return false;
	}

	public boolean hasInstructionList() {
		return _listToInsert != null;
	}

	public void addToPathIds(int id) {
		if (!_pathIds.contains(id))
			_pathIds.add(id);
	}

	public ArrayList<Integer> getPathIds() {
		return _pathIds;
	}
	
	public boolean allowAddToCFG(){
		return _addToCFG;
	}

	public void addToCFG() {
		_addToCFG = true;
	}
	
	public boolean isTargetOfGoto(){
		return _targetOfGoto;
	}

	public void targetOfGoto() {
		_targetOfGoto = true;
	}
}