/*******************************************************************************
 * Copyright (c) 2014 Obeo
 * 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:
 *     Obeo - initial API and implementation
 *******************************************************************************/
package org.eclipse.emf.ecoretools.design.service;

import org.eclipse.emf.ecore.EClass;
import org.eclipse.emf.ecore.EClassifier;
import org.eclipse.emf.ecore.EGenericType;
import org.eclipse.emf.ecore.ENamedElement;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.EOperation;
import org.eclipse.emf.ecore.EParameter;
import org.eclipse.emf.ecore.EStructuralFeature;
import org.eclipse.emf.ecore.ETypeParameter;
import org.eclipse.emf.ecore.ETypedElement;
import org.eclipse.emf.ecore.EcoreFactory;

public class EGenericsServices {

	public static String getETypeLabel(ETypedElement attr) {
		String typeName = null;
		if (attr.getEType() != null && attr.getEType().getName() != null) {
			typeName = attr.getEType().getName();
		}
		if (attr.getEGenericType() != null
				&& attr.getEGenericType().getETypeParameter() != null) {
			typeName = attr.getEGenericType().getETypeParameter().getName();
		}
		return typeName;
	}

	public static EObject getETypeOrParameter(ETypedElement attr) {
		if (attr.getEGenericType() != null
				&& attr.getEGenericType().getETypeParameter() != null) {
			return attr.getEGenericType().getETypeParameter();
		}
		if (attr.getEType() != null) {
			return attr.getEType();
		}
		return null;
	}

	public static Object findGenericType(ENamedElement attr, String typePart) {
		EClass parentClass = null;
		if (attr instanceof EStructuralFeature) {
			parentClass = ((EStructuralFeature) attr).getEContainingClass();
		} else if (attr instanceof EOperation) {
			parentClass = ((EOperation) attr).getEContainingClass();
		} else if (attr instanceof EParameter) {
			parentClass = ((EParameter) attr).getEOperation()
					.getEContainingClass();
		}
		Object value = null;
		if (parentClass != null && typePart != null) {
			for (ETypeParameter typeParam : parentClass.getETypeParameters()) {
				if (typePart.equals(typeParam.getName())) {
					value = typeParam;
				}
			}
		}
		return value;
	}

	public static void setETypeWithGenerics(ETypedElement typed, Object value) {
		EGenericType eGenericType = null;
		if (value instanceof EClassifier) {
			EClassifier eClassifier = (EClassifier) value;
			eGenericType = EcoreFactory.eINSTANCE.createEGenericType();
			eGenericType.setEClassifier(eClassifier);
			for (int i = 0, size = eClassifier.getETypeParameters().size(); i < size; ++i) {
				eGenericType.getETypeArguments().add(
						EcoreFactory.eINSTANCE.createEGenericType());
			}
			typed.setEGenericType(eGenericType);
		} else if (value instanceof ETypeParameter) {
			eGenericType = EcoreFactory.eINSTANCE.createEGenericType();
			eGenericType.setETypeParameter((ETypeParameter) value);
			typed.setEGenericType(eGenericType);
		}
	}
}