/*******************************************************************************
 * Copyright (c) 2005, 2008 IBM Corporation and others.
 * 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.jdt.internal.corext.refactoring.typeconstraints.typesets;

import java.util.LinkedHashMap;
import java.util.Map;

import org.eclipse.jdt.internal.corext.refactoring.typeconstraints.types.TType;
import org.eclipse.jdt.internal.corext.refactoring.typeconstraints.types.TypeEnvironment;



public class TypeSetEnvironment {

	private final TypeEnvironment fTypeEnvironment;
	private final TypeUniverseSet fUniverse;
	private final EmptyTypeSet fEmptyTypeSet;

	private final Map/*<TType, SubTypesOfSingleton>*/ fSubtypesOfSingletons= new LinkedHashMap();//@perf
	private final Map/*<TType, SubTypesSet>*/ fSubTypesSets= new LinkedHashMap();//@perf
	private final Map/*<TType, SuperTypesOfSingleton>*/ fSuperTypesOfSingletons= new LinkedHashMap();//@perf
	private final Map/*<TType, SuperTypesSet>*/ fSuperTypesSets= new LinkedHashMap();//@perf

	private int fgCommonExprHits= 0;
	private int fgCommonExprMisses= 0;

	public TypeSetEnvironment(TypeEnvironment typeEnvironment) {
		fTypeEnvironment= typeEnvironment;
		fUniverse= new TypeUniverseSet(this);
		fEmptyTypeSet= new EmptyTypeSet(this);
	}

	public TType getJavaLangObject() {
		return fTypeEnvironment.getJavaLangObject();
	}

	public TypeUniverseSet getUniverseTypeSet() {
		return fUniverse;
	}

	public EmptyTypeSet getEmptyTypeSet() {
		return fEmptyTypeSet;
	}

	public SubTypesOfSingleton createSubTypesOfSingleton(TType superType) {
		if (superType.isJavaLangObject())
			return this.getUniverseTypeSet();
		if (fSubtypesOfSingletons.containsKey(superType)) {
			fgCommonExprHits++;
			return (SubTypesOfSingleton) fSubtypesOfSingletons.get(superType);
		} else {
			SubTypesOfSingleton s= new SubTypesOfSingleton(superType, this);

			fgCommonExprMisses++;
			fSubtypesOfSingletons.put(superType, s);
			return s;
		}
	}

	public SubTypesSet createSubTypesSet(TypeSet superTypes) {
		if (fSubTypesSets.containsKey(superTypes)) {
			fgCommonExprHits++;
			return (SubTypesSet) fSubTypesSets.get(superTypes);
		} else {
			SubTypesSet s= new SubTypesSet(superTypes);

			fgCommonExprMisses++;
			fSubTypesSets.put(superTypes, s);
			return s;
		}
	}

	public SuperTypesOfSingleton createSuperTypesOfSingleton(TType subType) {
		if (fSuperTypesOfSingletons.containsKey(subType)) {
			fgCommonExprHits++;
			return (SuperTypesOfSingleton) fSuperTypesOfSingletons.get(subType);
		} else {
			SuperTypesOfSingleton s= new SuperTypesOfSingleton(subType, this);

			fgCommonExprMisses++;
			fSuperTypesOfSingletons.put(subType, s);
			return s;
		}
	}

	public SuperTypesSet createSuperTypesSet(TType subType) {
		if (fSuperTypesSets.containsKey(subType)) {
			fgCommonExprHits++;
			return (SuperTypesSet) fSuperTypesSets.get(subType);
		} else {
			SuperTypesSet s= new SuperTypesSet(subType, this);

			fgCommonExprMisses++;
			fSuperTypesSets.put(subType, s);
			return s;
		}
	}

	public SuperTypesSet createSuperTypesSet(TypeSet subTypes) {
		if (fSuperTypesSets.containsKey(subTypes))
			return (SuperTypesSet) fSuperTypesSets.get(subTypes);
		else {
			SuperTypesSet s= new SuperTypesSet(subTypes, this);

			fSuperTypesSets.put(subTypes, s);
			return s;
		}
	}

	public void dumpStats() {
		System.out.println("Common expression hits:   " + fgCommonExprHits); //$NON-NLS-1$
		System.out.println("Common expression misses: " + fgCommonExprMisses); //$NON-NLS-1$
	}

}
