Copyright (c) 2005, 2017 IBM Corporation 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:
    IBM Corporation - initial API and implementation
    Stephan Herrmann - Contributions for
							Bug 463330 - [dom] DOMFinder doesn't find the VariableBinding corresponding to a method argument
							Bug 464463 - [dom] DOMFinder doesn't find an ITypeParameter
							Bug 429813 - [1.8][dom ast] IMethodBinding#getJavaElement() should return IMethod for lambda
/*******************************************************************************
 * Copyright (c) 2005, 2017 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *     Stephan Herrmann - Contributions for
 *								Bug 463330 - [dom] DOMFinder doesn't find the VariableBinding corresponding to a method argument
 *								Bug 464463 - [dom] DOMFinder doesn't find an ITypeParameter
 *								Bug 429813 - [1.8][dom ast] IMethodBinding#getJavaElement() should return IMethod for lambda
 *******************************************************************************/
package org.eclipse.jdt.internal.core.util;

import org.eclipse.jdt.core.IInitializer;
import org.eclipse.jdt.core.ILocalVariable;
import org.eclipse.jdt.core.IMember;
import org.eclipse.jdt.core.ISourceRange;
import org.eclipse.jdt.core.ITypeParameter;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jdt.core.dom.ASTNode;
import org.eclipse.jdt.core.dom.ASTVisitor;
import org.eclipse.jdt.core.dom.AnnotationTypeDeclaration;
import org.eclipse.jdt.core.dom.AnnotationTypeMemberDeclaration;
import org.eclipse.jdt.core.dom.AnonymousClassDeclaration;
import org.eclipse.jdt.core.dom.ClassInstanceCreation;
import org.eclipse.jdt.core.dom.CompilationUnit;
import org.eclipse.jdt.core.dom.EnumConstantDeclaration;
import org.eclipse.jdt.core.dom.EnumDeclaration;
import org.eclipse.jdt.core.dom.IBinding;
import org.eclipse.jdt.core.dom.ImportDeclaration;
import org.eclipse.jdt.core.dom.Initializer;
import org.eclipse.jdt.core.dom.LambdaExpression;
import org.eclipse.jdt.core.dom.MarkerAnnotation;
import org.eclipse.jdt.core.dom.MethodDeclaration;
import org.eclipse.jdt.core.dom.ModuleDeclaration;
import org.eclipse.jdt.core.dom.NormalAnnotation;
import org.eclipse.jdt.core.dom.PackageDeclaration;
import org.eclipse.jdt.core.dom.ParameterizedType;
import org.eclipse.jdt.core.dom.SingleMemberAnnotation;
import org.eclipse.jdt.core.dom.SingleVariableDeclaration;
import org.eclipse.jdt.core.dom.TypeDeclaration;
import org.eclipse.jdt.core.dom.TypeParameter;
import org.eclipse.jdt.core.dom.VariableDeclarationFragment;
import org.eclipse.jdt.internal.core.LambdaMethod;
import org.eclipse.jdt.internal.core.SourceRefElement;

public class DOMFinder extends ASTVisitor {

	public ASTNode foundNode = null;
	public IBinding foundBinding = null;

	private CompilationUnit ast;
	private SourceRefElement element;
	private boolean resolveBinding;
	private int rangeStart = -1, rangeLength = 0;

	public DOMFinder(CompilationUnit ast, SourceRefElement element, boolean resolveBinding) {
		this.ast = ast;
		this.element = element;
		this.resolveBinding = resolveBinding;
	}

	protected boolean found(ASTNode node, ASTNode name) {
		if (name.getStartPosition() == this.rangeStart && name.getLength() == this.rangeLength) {
			this.foundNode = node;
			return true;
		}
		return false;
	}

	public ASTNode search() throws JavaModelException {
		ISourceRange range = null;
		if (this.element instanceof IMember && !(this.element instanceof IInitializer)
				&& !(this.element instanceof LambdaMethod) && !(this.element instanceof org.eclipse.jdt.internal.core.LambdaExpression))
			range = ((IMember) this.element).getNameRange();
		else if (this.element instanceof ITypeParameter || this.element instanceof ILocalVariable)
			range = this.element.getNameRange();
		else
			range = this.element.getSourceRange();
		this.rangeStart = range.getOffset();
		this.rangeLength = range.getLength();
		this.ast.accept(this);
		return this.foundNode;
	}

	@Override
	public boolean visit(AnnotationTypeDeclaration node) {
		if (found(node, node.getName()) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(AnnotationTypeMemberDeclaration node) {
		if (found(node, node.getName()) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(AnonymousClassDeclaration node) {
		ASTNode name;
		ASTNode parent = node.getParent();
		switch (parent.getNodeType()) {
			case ASTNode.CLASS_INSTANCE_CREATION:
				name = ((ClassInstanceCreation) parent).getType();
				if (name.getNodeType() == ASTNode.PARAMETERIZED_TYPE) {
					name = ((ParameterizedType) name).getType();
				}
				break;
			case ASTNode.ENUM_CONSTANT_DECLARATION:
				name = ((EnumConstantDeclaration) parent).getName();
				break;
			default:
				return true;
		}
		if (found(node, name) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(EnumConstantDeclaration node) {
		if (found(node, node.getName()) && this.resolveBinding)
			this.foundBinding = node.resolveVariable();
		return true;
	}

	@Override
	public boolean visit(EnumDeclaration node) {
		if (found(node, node.getName()) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(ImportDeclaration node) {
		if (found(node, node) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(Initializer node) {
		// note that no binding exists for an Initializer
		found(node, node);
		return true;
	}

	@Override
	public boolean visit(MarkerAnnotation node) {
		if (found(node, node) && this.resolveBinding)
			this.foundBinding = node.resolveAnnotationBinding();
		return true;
	}

	@Override
	public boolean visit(MethodDeclaration node) {
		if (found(node, node.getName()) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(ModuleDeclaration node) {
		if (found(node, node.getName()) && this.resolveBinding) {
			this.foundBinding = node.resolveBinding();
		}
		return true;
	}
	@Override
	public boolean visit(NormalAnnotation node) {
		if (found(node, node) && this.resolveBinding)
			this.foundBinding = node.resolveAnnotationBinding();
		return true;
	}

	@Override
	public boolean visit(PackageDeclaration node) {
		if (found(node, node) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(SingleMemberAnnotation node) {
		if (found(node, node) && this.resolveBinding)
			this.foundBinding = node.resolveAnnotationBinding();
		return true;
	}

	@Override
	public boolean visit(TypeDeclaration node) {
		if (found(node, node.getName()) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(TypeParameter node) {
		if (found(node, node.getName()) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(VariableDeclarationFragment node) {
		if (found(node, node.getName()) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;
	}

	@Override
	public boolean visit(SingleVariableDeclaration node) {
		if (found(node, node.getName()) && this.resolveBinding)
			this.foundBinding = node.resolveBinding();
		return true;		
	}

	@Override
	public boolean visit(LambdaExpression node) {
		if (found(node, node) && this.resolveBinding)
			this.foundBinding = node.resolveMethodBinding();
		return true;
	}
}