code: /***************************************************************************
   *   Copyright (C) by Fabrizio Montesi                                     *
   *                                                                         *
   *   This program is free software; you can redistribute it and/or modify  *
   *   it under the terms of the GNU Library General Public License as       *
   *   published by the Free Software Foundation; either version 2 of the    *
   *   License, or (at your option) any later version.                       *
   *                                                                         *
   *   This program 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.                          *
   *                                                                         *
   *   You should have received a copy of the GNU Library General Public     *
   *   License along with this program; if not, write to the                 *
   *   Free Software Foundation, Inc.,                                       *
   *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
   *                                                                         *
   *   For details about the authors of this software, see the AUTHORS file. *
   ***************************************************************************/
  
  package jolie.lang.parse.ast;
  
  import java.io.Serializable;
  import java.util.ArrayList;
  import java.util.List;
  import jolie.lang.Constants;
  import jolie.lang.parse.OLVisitor;
  import jolie.lang.parse.ast.expression.ConstantIntegerExpression;
  import jolie.lang.parse.ast.expression.ConstantStringExpression;
  import jolie.lang.parse.context.ParsingContext;
  import jolie.util.Pair;
  
  
  public class VariablePathNode extends OLSyntaxNode implements Serializable
  {
  	public static enum Type {
  		NORMAL,
  		GLOBAL,
  		CSET
  	}
  
  	private final List< Pair< OLSyntaxNode, OLSyntaxNode > > path;
  	private final Type type;
  
  	public VariablePathNode( ParsingContext context, Type type )
  	{
  		super( context );
  		path = new ArrayList<>();
  		this.type = type;
  	}
  
  	public Type type()
  	{
  		return type;
  	}
  	
  	public boolean isGlobal()
  	{
  		return type == Type.GLOBAL;
  	}
  
  	public boolean isCSet()
  	{
  		return type == Type.CSET;
  	}
  
  	public boolean isStatic()
  	{
  		for( Pair< OLSyntaxNode, OLSyntaxNode > node : path ) {
  			if ( node.key() instanceof ConstantStringExpression == false ) {
  				return false;
  			}
  			if ( node.value() != null && node.value() instanceof ConstantIntegerExpression == false ) {
  				return false;
  			}
  		}
  		return true;
  	}
  
  	public static void levelPaths( VariablePathNode leftPath, VariablePathNode rightPath )
  	{
  		int leftIndex = leftPath.path().size() - 1;
  		int rightIndex = rightPath.path().size() - 1;
  
  		Pair< OLSyntaxNode, OLSyntaxNode > left = leftPath.path().get( leftIndex );
  		Pair< OLSyntaxNode, OLSyntaxNode > right = rightPath.path().get( rightIndex );
  
  		if ( left.value() == null && right.value() != null ) {
  			left = new Pair<>(
  					left.key(),
  					new ConstantIntegerExpression( leftPath.context(), 0 )
  				);
  			leftPath.path().set( leftIndex, left );
  		} else if ( left.value() != null && right.value() == null ) {
  			right = new Pair<>(
  					right.key(),
  					new ConstantIntegerExpression( rightPath.context(), 0 )
  				);
  			rightPath.path().set( rightIndex, right );
  		}
  	}
  	
  	public void append( Pair< OLSyntaxNode, OLSyntaxNode > node )
  	{
  		path.add( node );
  	}
  	
  	public List< Pair< OLSyntaxNode, OLSyntaxNode > > path()
  	{
  		return path;
  	}
  
  	@Override
  	public void accept( OLVisitor visitor )
  	{
  		visitor.visit( this );
  	}
  
  	public boolean isEquivalentTo( VariablePathNode right )
  	{
  		return checkVariablePathNodeEquivalence( this, right );
  	}
  
  	private static boolean checkVariablePathNodeEquivalence( VariablePathNode left, VariablePathNode right )
  	{
  		if ( left.path.size() != right.path.size() ) {
  			return false;
  		}
  
  		if ( left.type != right.type ) {
  			return false;
  		}
  
  		Pair< OLSyntaxNode, OLSyntaxNode > leftPair, rightPair;
  		for( int i = 0; i < left.path.size(); i++ ) {
  			leftPair = left.path.get( i );
  			rightPair = right.path.get( i );
  			if ( checkNodeKeyEquivalence( leftPair.key(), rightPair.key() ) == false ||
  				checkNodeIndexEquivalence( leftPair.value(), rightPair.value() ) == false
  			) {
  				return false;
  			}
  		}
  		return true;
  	}
  
  	private static boolean checkNodeKeyEquivalence( OLSyntaxNode left, OLSyntaxNode right )
  	{
  		if ( left.equals( right ) ) {
  			return true;
  		}
  
  		if ( left instanceof ConstantStringExpression && right instanceof ConstantStringExpression ) {
  			return ((ConstantStringExpression)left).value().equals( ((ConstantStringExpression)right).value() );
  		}
  
  		return false;
  	}
  
  	private static boolean checkNodeIndexEquivalence( OLSyntaxNode left, OLSyntaxNode right )
  	{
  		if ( left == right ) { // Used for null values and same objects
  			return true;
  		}
  
  		if ( left == null && right instanceof ConstantIntegerExpression ) {
  			return ((ConstantIntegerExpression)right).value() == 0;
  		}
  
  		if ( right == null && left instanceof ConstantIntegerExpression ) {
  			return ((ConstantIntegerExpression)left).value() == 0;
  		}
  
  		if ( left != null && right != null ) {
  			if ( left.equals( right ) ) {
  				return true;
  			}
  			
  			if ( left instanceof ConstantIntegerExpression && right instanceof ConstantIntegerExpression ) {
  				return ((ConstantIntegerExpression)left).value() == ((ConstantIntegerExpression)right).value();
  			}
  		}
  
  		return false;
  	}
  
  	public String toPrettyString()
  	{
  		StringBuilder builder = new StringBuilder();
  		Pair< OLSyntaxNode, OLSyntaxNode > node;
  		if ( isGlobal() ) {
  			builder.append( Constants.GLOBAL ).append( '.' );
  		}
  		for( int i = 0; i < path.size(); i++ ) {
  			node = path.get( i );
  			if ( node.key() instanceof ConstantStringExpression ) {
  				builder.append( ((ConstantStringExpression)node.key()).value() );
  			} else {
  				builder.append( "<Expression>" );
  			}
  			if ( node.value() != null ) {
  				if ( node.value() instanceof ConstantIntegerExpression ) {
  					ConstantIntegerExpression expr = (ConstantIntegerExpression) node.value();
  					if ( expr.value() != 0 ) {
  						builder.append( '[' )
  							.append( node.value() )
  							.append( ']' );
  					}
  				} else {
  					builder.append( '[' )
  							.append( "<Expression>" )
  							.append( ']' );
  				}
  			}
  			
  			if ( i < path.size() - 1 ) {
  				builder.append( '.' );
  			}
  		}
  		return builder.toString();
  	}
  }
  