/*******************************************************************************
 * Copyright (c) 2008, 2014 IBM Wind River Systems, Inc. and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     Markus Schorn - Initial API and implementation
 *     Sergey Prigogin (Google)
 *     Thomas Corbat (IFS)
 *******************************************************************************/
package org.eclipse.cdt.internal.core.dom.parser.cpp;

import org.eclipse.cdt.core.dom.ast.ASTVisitor;
import org.eclipse.cdt.core.dom.ast.IASTAttribute;
import org.eclipse.cdt.core.dom.ast.IASTAttributeSpecifier;
import org.eclipse.cdt.core.dom.ast.IASTDeclarator;
import org.eclipse.cdt.core.dom.ast.IASTInitializer;
import org.eclipse.cdt.core.dom.ast.IASTName;
import org.eclipse.cdt.core.dom.ast.IASTNode;
import org.eclipse.cdt.core.dom.ast.IASTPointerOperator;
import org.eclipse.cdt.core.dom.ast.IScope;
import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTDeclarator;
import org.eclipse.cdt.core.parser.util.ArrayUtil;
import org.eclipse.cdt.internal.core.dom.parser.ASTAmbiguousNode;
import org.eclipse.cdt.internal.core.dom.parser.IASTAmbiguousDeclarator;
import org.eclipse.cdt.internal.core.dom.parser.cpp.semantics.CPPVisitor;
import org.eclipse.core.runtime.Assert;

/**
 * Handles ambiguities when parsing declarators.
 * <br>
 * Example: void f(int (D));  // is D a type?
 */
public class CPPASTAmbiguousDeclarator extends ASTAmbiguousNode implements IASTAmbiguousDeclarator, ICPPASTDeclarator {
	private IASTDeclarator[] dtors = new IASTDeclarator[2];
	private int dtorPos = -1;
	private IASTInitializer fInitializer;

	public CPPASTAmbiguousDeclarator(IASTDeclarator... decls) {
		for (IASTDeclarator d : decls) {
			if (d != null) {
				addDeclarator(d);
			}
		}
	}

	@Override
	protected void beforeResolution() {
		// populate containing scope, so that it will not be affected by the alternative branches.
		IScope scope = CPPVisitor.getContainingNonTemplateScope(this);
		if (scope instanceof ICPPASTInternalScope) {
			((ICPPASTInternalScope) scope).populateCache();
		}
	}

	@Override
	protected void afterResolution(ASTVisitor resolver, IASTNode best) {
		// if we have an initializer it needs to be added to the chosen alternative.
		// we also need to resolve ambiguities in the initializer.
		if (fInitializer != null) {
			((IASTDeclarator) best).setInitializer(fInitializer);
			fInitializer.accept(resolver);
		}
	}

	@Override
	public IASTDeclarator copy() {
		throw new UnsupportedOperationException();
	}

	@Override
	public IASTDeclarator copy(CopyStyle style) {
		throw new UnsupportedOperationException();
	}

	@Override
	public void addDeclarator(IASTDeclarator d) {
		assertNotFrozen();
		if (d != null) {
			dtors = ArrayUtil.appendAt(IASTDeclarator.class, dtors, ++dtorPos, d);
			d.setParent(this);
			d.setPropertyInParent(SUBDECLARATOR);
		}
	}

	@Override
	public IASTDeclarator[] getDeclarators() {
		dtors = ArrayUtil.trimAt(IASTDeclarator.class, dtors, dtorPos);
		return dtors;
	}

	@Override
	public IASTNode[] getNodes() {
		return getDeclarators();
	}

	@Override
	public IASTInitializer getInitializer() {
		return fInitializer;
	}

	@Override
	public IASTName getName() {
		return dtors[0].getName();
	}

	@Override
	public IASTDeclarator getNestedDeclarator() {
		return dtors[0].getNestedDeclarator();
	}

	@Override
	public IASTPointerOperator[] getPointerOperators() {
		return dtors[0].getPointerOperators();
	}

	@Override
	public void addPointerOperator(IASTPointerOperator operator) {
		assertNotFrozen();
		Assert.isLegal(false);
	}

	@Override
	public IASTAttribute[] getAttributes() {
		return dtors[0].getAttributes();
	}

	@Override
	@Deprecated
	public void addAttribute(IASTAttribute attribute) {
		assertNotFrozen();
		Assert.isLegal(false);
	}

	@Override
	public IASTAttributeSpecifier[] getAttributeSpecifiers() {
		return dtors[0].getAttributeSpecifiers();
	}

	@Override
	public void addAttributeSpecifier(IASTAttributeSpecifier attributeSpecifier) {
		assertNotFrozen();
		Assert.isLegal(false);
	}

	@Override
	public int getRoleForName(IASTName name) {
		return dtors[0].getRoleForName(name);
	}

	@Override
	public void setInitializer(IASTInitializer initializer) {
		// store the initializer until the ambiguity is resolved
		fInitializer = initializer;
	}

	@Override
	public void setName(IASTName name) {
		assertNotFrozen();
		Assert.isLegal(false);
	}

	@Override
	public void setNestedDeclarator(IASTDeclarator nested) {
		assertNotFrozen();
		Assert.isLegal(false);
	}

	@Override
	public boolean declaresParameterPack() {
		return false;
	}

	@Override
	public void setDeclaresParameterPack(boolean val) {
		assertNotFrozen();
		Assert.isLegal(false);
	}
}
