bundles/core/org.eclipse.apogy.core.programs.javascript/src/org/eclipse/apogy/core/programs/javascript/TypeMemberProxy.java

/*******************************************************************************
 * Copyright (c) 2018 Agence spatiale canadienne / Canadian Space Agency 
 * 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:
 *    Mathieu Larose (Savoir-faire Linux) - Initial API and implementation
 *
 * SPDX-License-Identifier: EPL-1.0
 *     
 *******************************************************************************/
package org.eclipse.apogy.core.programs.javascript;

import java.lang.reflect.Method;

import org.eclipse.apogy.common.emf.ApogyCommonEMFFacade;
import org.eclipse.apogy.common.emf.ApogyCommonEMFFactory;
import org.eclipse.apogy.common.emf.ListFeatureNode;
import org.eclipse.apogy.common.emf.ListRootNode;
import org.eclipse.apogy.core.invocator.ApogyCoreInvocatorFacade;
import org.eclipse.apogy.core.invocator.TypeMember;
import org.eclipse.apogy.core.invocator.TypeMemberReferenceListElement;
import org.eclipse.apogy.core.invocator.VariableFeatureReference;
import org.eclipse.emf.ecore.EAttribute;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.EOperation;
import org.eclipse.emf.ecore.EReference;
import org.eclipse.emf.ecore.EStructuralFeature;
import org.eclipse.emf.ecore.util.EcoreUtil;
import org.mozilla.javascript.Scriptable;
import org.mozilla.javascript.ScriptableObject;

/**
 * Proxy for an EObject obtained through a {@link TypeMember}
 *
 */
public class TypeMemberProxy extends ScriptableObject {
	private static final long serialVersionUID = 1L;

	private VariableFeatureReference variableFeatureReference;
	private JavaScriptProgram program;

	public TypeMemberProxy() {
		// Rhino requires an empty constructor
	}

	/**
	 *
	 * @param variableFeatureReference {@link VariableFeaturerReference}
	 *                                 representing the EObject wrapped by this
	 *                                 classs
	 * @param program                  JavaScriptProgram being executed
	 * @throws NoSuchMethodException
	 * @throws SecurityException
	 */
	public TypeMemberProxy(VariableFeatureReference variableFeatureReference, JavaScriptProgram program)
			throws NoSuchMethodException, SecurityException {
		this.variableFeatureReference = variableFeatureReference;
		this.program = program;
		init();
	}

	private void init() throws NoSuchMethodException, SecurityException {
		EObject instance = ApogyCoreInvocatorFacade.INSTANCE.getInstance(this.variableFeatureReference);

		for (EOperation operation : ApogyCommonEMFFacade.INSTANCE.getAllAvailableEOperations(instance.eClass())) {
			defineProperty(operation.getName(),
					new OperationCallInvoker(this.program, this.variableFeatureReference, operation), 0);
		}

		for (EStructuralFeature structuralFeature : instance.eClass().getEAllStructuralFeatures()) {
			if (structuralFeature instanceof EReference) {
				ReferenceGetter referenceGetter = new ReferenceGetter(structuralFeature);
				Method getter = ReferenceGetter.class.getDeclaredMethod("get", new Class[] { Scriptable.class });
				defineProperty(structuralFeature.getName(), referenceGetter, getter, null, 0);
			} else if (structuralFeature instanceof EAttribute) {
				AttributeGetter attributeGetter = new AttributeGetter(this.variableFeatureReference, structuralFeature);
				Method getter = AttributeGetter.class.getDeclaredMethod("get", new Class[] { Scriptable.class });
				defineProperty(structuralFeature.getName(), attributeGetter, getter, null, 0);
			}
		}

		TypeMemberReferenceListElement child = this.variableFeatureReference.getTypeMemberReferenceListElement();

		while (child != null) {
			for (TypeMember typeMember : child.getTypeMember().getMemberType().getMembers()) {
				// If the property already exists and is read-only, defineProperty
				// is ignored.
				//
				// Delete the property in case it already exists and is
				// read-only (which is likely the case since we defined read-only
				// properties for all EReferences in the loop above).
				delete(typeMember.getName());

				TypeMemberGetter typeMemberGetter = new TypeMemberGetter(typeMember);
				Method getter = TypeMemberGetter.class.getDeclaredMethod("get", new Class[] { Scriptable.class });
				defineProperty(typeMember.getName(), typeMemberGetter, getter, null, 0);
			}

			child = child.getChild();

		}
	}

	@Override
	public String getClassName() {
		return "TypeMemberProxy";
	}

	/**
	 * Gets a reference of the EObject wrapped by {@link TypeMemberProxy}
	 *
	 */
	private class ReferenceGetter {
		private final EStructuralFeature feature;

		public ReferenceGetter(EStructuralFeature feature) {
			this.feature = feature;
		}

		/**
		 * Returns the reference (represented by this class) of the EObject (represented
		 * by {@TypeMemberProxy})
		 * 
		 * @param self The JavaScript object
		 * @return the attribute
		 */
		@SuppressWarnings("unused")
		public Object get(Scriptable self) throws NoSuchMethodException, SecurityException {
			assert TypeMemberProxy.this.variableFeatureReference.getFeatureRoot() == null;

			VariableFeatureReference subVariableFeatureReference = EcoreUtil
					.copy(TypeMemberProxy.this.variableFeatureReference);

			ListRootNode root = ApogyCommonEMFFactory.eINSTANCE.createListRootNode();
			ListFeatureNode node = ApogyCommonEMFFactory.eINSTANCE.createListFeatureNode();
			node.setStructuralFeature(this.feature);
			root.setChild(node);
			EObject instance = ApogyCoreInvocatorFacade.INSTANCE
					.getInstance(TypeMemberProxy.this.variableFeatureReference);
			root.setSourceClass(instance.eClass());
			subVariableFeatureReference.setFeatureRoot(root);

			Scriptable object = new ReferenceProxy(subVariableFeatureReference, TypeMemberProxy.this.program);
			object.setParentScope(TypeMemberProxy.this);
			return object;
		}
	}

	/**
	 * Gets a type member of the EObject wrapped by {@link TypeMemberProxy}
	 *
	 */
	private class TypeMemberGetter {
		private final TypeMember typeMember;

		public TypeMemberGetter(TypeMember typeMember) {
			this.typeMember = typeMember;
		}

		/**
		 * Returns the type member (represented by this class) of the EObject
		 * (represented by {TypeMemberProxy})
		 * 
		 * @param self The JavaScript object
		 * @return the attribute
		 */
		@SuppressWarnings("unused")
		public TypeMemberProxy get(Scriptable self) throws NoSuchMethodException, SecurityException {
			VariableFeatureReference subVariableFeatureReference = EcoreUtil
					.copy(TypeMemberProxy.this.variableFeatureReference);

			VariableFeatureReferenceUtil util = new VariableFeatureReferenceUtil();
			util.createTypeMemberHierarchy(subVariableFeatureReference, this.typeMember);

			return new TypeMemberProxy(subVariableFeatureReference, TypeMemberProxy.this.program);
		}
	}
}