/*******************************************************************************
 * Copyright (c) 2011 Bruno Medeiros and other Contributors.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Bruno Medeiros - initial API and implementation
 *******************************************************************************/
package dtool.ast.expressions;

import melnorme.lang.tooling.ast.CommonASTNode;
import melnorme.lang.tooling.ast.IASTVisitor;
import melnorme.lang.tooling.ast.util.ASTCodePrinter;
import melnorme.lang.tooling.ast_actual.ASTNodeTypes;
import melnorme.lang.tooling.engine.PickedElement;
import melnorme.lang.tooling.engine.resolver.ConcreteElementSemantics;
import melnorme.lang.tooling.engine.resolver.NamedElementSemantics;
import melnorme.lang.tooling.engine.scoping.CommonScopeLookup;
import melnorme.lang.tooling.symbols.IConcreteNamedElement;
import melnorme.lang.tooling.symbols.INamedElement;
import dtool.ast.definitions.DefSymbol;
import dtool.ast.definitions.DefUnit;
import dtool.ast.definitions.EArcheType;

/**
 * A lambda expression in the short, simple syntax:
 * <code> Identifier => AssignExpression </code>
 */
public class ExpSimpleLambda extends Expression {
	
	public final SimpleLambdaDefUnit simpleLambdaDefUnit;
	public final Expression bodyExpression;
	
	public ExpSimpleLambda(SimpleLambdaDefUnit simpleLambdaDefUnit, Expression bodyExpression) {
		this.simpleLambdaDefUnit = parentize(simpleLambdaDefUnit);
		this.bodyExpression = parentize(bodyExpression);
	}
	
	@Override
	public ASTNodeTypes getNodeType() {
		return ASTNodeTypes.EXP_SIMPLE_LAMBDA;
	}
	
	@Override
	public void visitChildren(IASTVisitor visitor) {
		acceptVisitor(visitor, simpleLambdaDefUnit);
		acceptVisitor(visitor, bodyExpression);
	}
	
	@Override
	protected CommonASTNode doCloneTree() {
		return new ExpSimpleLambda(clone(simpleLambdaDefUnit), clone(bodyExpression));
	}
	
	@Override
	public void toStringAsCode(ASTCodePrinter cp) {
		cp.append(simpleLambdaDefUnit, " => ");
		cp.append(bodyExpression);
	}
	
	public static class SimpleLambdaDefUnit extends DefUnit implements IConcreteNamedElement {
		
		public SimpleLambdaDefUnit(DefSymbol defName) {
			super(defName);
		}
		
		@Override
		public ASTNodeTypes getNodeType() {
			return ASTNodeTypes.SIMPLE_LAMBDA_DEFUNIT;
		}
		
		@Override
		public void visitChildren(IASTVisitor visitor) {
			acceptVisitor(visitor, defName);
		}
		
		@Override
		protected CommonASTNode doCloneTree() {
			return new SimpleLambdaDefUnit(clone(defName));
		}
		
		@Override
		public void toStringAsCode(ASTCodePrinter cp) {
			cp.append(defName);
		}
		
		@Override
		public EArcheType getArcheType() {
			return EArcheType.Variable;
		}
		
		/* -----------------  ----------------- */
		
		@Override
		protected NamedElementSemantics doCreateSemantics(PickedElement<?> pickedElement) {
			return new ConcreteElementSemantics(this, pickedElement) {
				
				@Override
				public void resolveSearchInMembersScope(CommonScopeLookup search) {
					 // Do nothing
				}
				
				@Override
				public INamedElement getTypeForValueContext_do() {
					// It would have to be deduced from the exp context.
					return null;
				}
				
			};
		}
		
	}
	
}