OoasTools

/**

  *

  *                      OOAS Compiler

  *

  *       Copyright 2015, AIT Austrian Institute of Technology.

  * This code is based on the C# Version of the OOAS Compiler, which is

  * copyright 2015 by the Institute of Software Technology, Graz University

  * of Technology with portions copyright by the AIT Austrian Institute of

  * Technology. All rights reserved.

  *

  * SEE THE "LICENSE" FILE FOR THE TERMS UNDER WHICH THIS FILE IS PROVIDED.

  *

  * If you modify the file please update the list of contributors below to in-

  * clude your name. Please also stick to the coding convention of using TABs

  * to do the basic (block-level) indentation and spaces for anything after

  * that. (Enable the display of special chars and it should be pretty obvious

  * what this means.) Also, remove all trailing whitespace.

  *

  * Contributors:

  *               Willibald Krenn (AIT)

  *               Stephan Zimmerer (AIT)

  *               Markus Demetz (AIT)

  *               Christoph Czurda (AIT)

  *

  */

package org.momut.ooas.visitors;

import java.util.HashSet;

/// <summary>

/// Requires: ResolveOpaque

///

/// Checks whether types have been defined in a sane way (no self refs etc.)

/// </summary>

public final class OoaTypesVisitor extends OoaCompleteAstTraversalVisitor

{

	private void Error(UlyssesType aType, String p)

	{

		ParserError error = new ParserError(m_ParserState.filename,

				aType.identifier().line(), aType.identifier().column(), p);

		m_ParserState.AddErrorMessage(error);

	}

	HashSet<UlyssesType> typesSeen = new HashSet<UlyssesType>();

	@Override

	public void visit(MainModule mainModule)

	{

		for (Identifier x: mainModule.symbolTable().symbolList())

		{

			if (x.kind() == IdentifierKind.TypeIdentifier)

				x.Accept(this);

		}

	}

	@Override

	protected void VisitAstElement(IAst element, IAst parent)

	{

		if (element.nodeType() != AstNodeTypeEnum.type)

			m_visited.add(element);

		super.VisitAstElement(element, parent);

	}

	@Override

	public void visit(TypeIdentifier typeIdentifier)

	{

		typesSeen.clear();

		super.visit(typeIdentifier);

	}

	private interface Action<T extends UlyssesType> {

		void doIt(T param);

	}

	/* Does the check for recursion */

	private <T extends UlyssesType> void CheckForRecursion(T aType, String Message, Action<T> toCall)

	{

		if (typesSeen.contains(aType))

		{

			Error(aType, Message);

			return;

		}

		typesSeen.add(aType);

		try

		{

			toCall.doIt(aType);

		}

		finally

		{

			typesSeen.remove(aType);

		}

	}

	/* see whether a tuple-type includes itself */

	public void HackUntilCSharp4(TupleType t)

	{ super.visit(t); }

	@Override

	public void visit(TupleType tupleType)

	{

		this.<TupleType>CheckForRecursion(tupleType,

				String.format("Tuple contains itself: '%s' (Recursive definitions not allowed.)",

						tupleType.toString()),

				new Action<TupleType>(){

					@Override

					public void doIt(TupleType param) {

						HackUntilCSharp4(param);

				}}); // (x) => HackUntilCSharp4(x));

	}

	/* see whether a list-type includes itself */

	public void HackUntilCSharp4(ListType t)

	{ super.visit(t); }

	@Override

	public void visit(ListType listType)

	{

		this.<ListType>CheckForRecursion(listType,

				String.format("List contains itself: '%s' (Recursive definitions not allowed.)",

						listType.toString()),

				new Action<ListType>(){

					@Override

					public void doIt(ListType param) {

						HackUntilCSharp4(param);

				}}); // (x) => HackUntilCSharp4(x));

	}

	/* see whether a map-type includes itself */

	public void HackUntilCSharp4(MapType t)

	{ super.visit(t); }

	@Override

	public void visit(MapType mapType)

	{

		this.<MapType>CheckForRecursion(mapType,

				String.format("Map contains itself: '%s' (Recursive definitions not allowed.)",

						mapType.toString()),

				new Action<MapType>(){

					@Override

					public void doIt(MapType param) {

						HackUntilCSharp4(param);

					}}); // (x) => HackUntilCSharp4(x));

	}

	@Override

	public void visit(OoActionSystemType ooActionSystemType)

	{

		// do not go into classes..

	}

	public OoaTypesVisitor(ParserState aState)

	{

		super (aState, true);

		if (aState == null)

			throw new ArgumentException();

	}