/*

 * Copyright (C) 2007-2010 Júlio Vilmar Gesser.

 * Copyright (C) 2011, 2013-2021 The JavaParser Team.

 *

 * This file is part of JavaParser.

 *

 * JavaParser can be used either under the terms of

 * a) the GNU Lesser General Public License as published by

 *     the Free Software Foundation, either version 3 of the License, or

 *     (at your option) any later version.

 * b) the terms of the Apache License

 *

 * You should have received a copy of both licenses in LICENCE.LGPL and

 * LICENCE.APACHE. Please refer to those files for details.

 *

 * JavaParser is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU Lesser General Public License for more details.

 */

package com.github.javaparser.ast.expr;

import com.github.javaparser.TokenRange;

import com.github.javaparser.ast.AllFieldsConstructor;

import com.github.javaparser.ast.Generated;

import com.github.javaparser.ast.Node;

import com.github.javaparser.ast.observer.ObservableProperty;

import com.github.javaparser.ast.visitor.CloneVisitor;

import com.github.javaparser.ast.visitor.GenericVisitor;

import com.github.javaparser.ast.visitor.VoidVisitor;

import com.github.javaparser.metamodel.JavaParserMetaModel;

import com.github.javaparser.metamodel.OptionalProperty;

import com.github.javaparser.metamodel.ThisExprMetaModel;

import com.github.javaparser.resolution.Resolvable;

import com.github.javaparser.resolution.declarations.ResolvedTypeDeclaration;

import java.util.Optional;

import java.util.function.Consumer;

/**

 * An occurrence of the "this" keyword. <br>

 * {@code World.this.greet()} is a MethodCallExpr of method name greet,

 * and scope "World.this" which is a ThisExpr with typeName "World". <br>

 * {@code this.name} is a FieldAccessExpr of field greet, and a ThisExpr as its scope.

 * This ThisExpr has no typeName.

 *

 * @author Julio Vilmar Gesser

 * @see com.github.javaparser.ast.stmt.ExplicitConstructorInvocationStmt

 * @see SuperExpr

 */

public class ThisExpr extends Expression implements Resolvable<ResolvedTypeDeclaration> {

    @OptionalProperty

    private Name typeName;

    public ThisExpr() {

        this(null, null);

    }

    @AllFieldsConstructor

    public ThisExpr(final Name typeName) {

        this(null, typeName);

    }

    /**

     * This constructor is used by the parser and is considered private.

     */

    @Generated("com.github.javaparser.generator.core.node.MainConstructorGenerator")

    public ThisExpr(TokenRange tokenRange, Name typeName) {

        super(tokenRange);

        setTypeName(typeName);

        customInitialization();

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.AcceptGenerator")

    public <R, A> R accept(final GenericVisitor<R, A> v, final A arg) {

        return v.visit(this, arg);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.AcceptGenerator")

    public <A> void accept(final VoidVisitor<A> v, final A arg) {

        v.visit(this, arg);

    }

    @Generated("com.github.javaparser.generator.core.node.PropertyGenerator")

    public Optional<Name> getTypeName() {

        return Optional.ofNullable(typeName);

    }

    @Generated("com.github.javaparser.generator.core.node.PropertyGenerator")

    public ThisExpr setTypeName(final Name typeName) {

        if (typeName == this.typeName) {

            return this;

        }

        notifyPropertyChange(ObservableProperty.TYPE_NAME, this.typeName, typeName);

        if (this.typeName != null)

            this.typeName.setParentNode(null);

        this.typeName = typeName;

        setAsParentNodeOf(typeName);

        return this;

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.RemoveMethodGenerator")

    public boolean remove(Node node) {

        if (node == null)

            return false;

        if (typeName != null) {

            if (node == typeName) {

                removeTypeName();

                return true;

            }

        }

        return super.remove(node);

    }

    @Generated("com.github.javaparser.generator.core.node.RemoveMethodGenerator")

    public ThisExpr removeClassName() {

        return setTypeName((Name) null);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.CloneGenerator")

    public ThisExpr clone() {

        return (ThisExpr) accept(new CloneVisitor(), null);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.GetMetaModelGenerator")

    public ThisExprMetaModel getMetaModel() {

        return JavaParserMetaModel.thisExprMetaModel;

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.ReplaceMethodGenerator")

    public boolean replace(Node node, Node replacementNode) {

        if (node == null)

            return false;

        if (typeName != null) {

            if (node == typeName) {

                setTypeName((Name) replacementNode);

                return true;

            }

        }

        return super.replace(node, replacementNode);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")

    public boolean isThisExpr() {

        return true;

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")

    public ThisExpr asThisExpr() {

        return this;

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")

    public void ifThisExpr(Consumer<ThisExpr> action) {

        action.accept(this);

    }

    @Override

    public ResolvedTypeDeclaration resolve() {

        return getSymbolResolver().resolveDeclaration(this, ResolvedTypeDeclaration.class);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")

    public Optional<ThisExpr> toThisExpr() {

        return Optional.of(this);

    }

    @Generated("com.github.javaparser.generator.core.node.RemoveMethodGenerator")

    public ThisExpr removeTypeName() {

        return setTypeName((Name) null);

    }

}