/*
 * Copyright (C) 2007-2010 Júlio Vilmar Gesser.
 * Copyright (C) 2011, 2013-2016 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.body;

import com.github.javaparser.ast.AllFieldsConstructor;
import com.github.javaparser.ast.Modifier;
import com.github.javaparser.ast.Node;
import com.github.javaparser.ast.NodeList;
import com.github.javaparser.ast.expr.AnnotationExpr;
import com.github.javaparser.ast.expr.AssignExpr;
import com.github.javaparser.ast.expr.AssignExpr.Operator;
import com.github.javaparser.ast.expr.NameExpr;
import com.github.javaparser.ast.nodeTypes.NodeWithJavadoc;
import com.github.javaparser.ast.nodeTypes.NodeWithVariables;
import com.github.javaparser.ast.nodeTypes.modifiers.NodeWithAccessModifiers;
import com.github.javaparser.ast.nodeTypes.modifiers.NodeWithFinalModifier;
import com.github.javaparser.ast.nodeTypes.modifiers.NodeWithStaticModifier;
import com.github.javaparser.ast.observer.ObservableProperty;
import com.github.javaparser.ast.stmt.BlockStmt;
import com.github.javaparser.ast.stmt.ReturnStmt;
import com.github.javaparser.ast.type.Type;
import com.github.javaparser.ast.type.VoidType;
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.FieldDeclarationMetaModel;
import com.github.javaparser.metamodel.JavaParserMetaModel;
import com.github.javaparser.metamodel.NonEmptyProperty;
import java.util.Arrays;
import java.util.EnumSet;
import java.util.List;
import java.util.Optional;
import static com.github.javaparser.ast.Modifier.*;
import static com.github.javaparser.ast.NodeList.nodeList;
import static com.github.javaparser.utils.Utils.assertNotNull;
import javax.annotation.Generated;
import com.github.javaparser.TokenRange;
import com.github.javaparser.resolution.Resolvable;
import com.github.javaparser.resolution.declarations.ResolvedConstructorDeclaration;
import com.github.javaparser.resolution.declarations.ResolvedFieldDeclaration;
import java.util.function.Consumer;

/**
 * The declaration of a field in a class. "private static int a=15*15;" in this example: <code>class X { private static
 * int a=15*15; }</code>
 *
 * <br/>All annotations preceding the type will be set on this object, not on the type.
 * JavaParser doesn't know if it they are applicable to the method or the type.
 *
 * @author Julio Vilmar Gesser
 */
public final class FieldDeclaration extends BodyDeclaration<FieldDeclaration> implements NodeWithJavadoc<FieldDeclaration>, NodeWithVariables<FieldDeclaration>, NodeWithAccessModifiers<FieldDeclaration>, NodeWithStaticModifier<FieldDeclaration>, NodeWithFinalModifier<FieldDeclaration>, Resolvable<ResolvedFieldDeclaration> {

    private EnumSet<Modifier> modifiers;

    @NonEmptyProperty
    private NodeList<VariableDeclarator> variables;

    public FieldDeclaration() {
        this(null, EnumSet.noneOf(Modifier.class), new NodeList<>(), new NodeList<>());
    }

    public FieldDeclaration(EnumSet<Modifier> modifiers, VariableDeclarator variable) {
        this(null, modifiers, new NodeList<>(), nodeList(variable));
    }

    public FieldDeclaration(EnumSet<Modifier> modifiers, NodeList<VariableDeclarator> variables) {
        this(null, modifiers, new NodeList<>(), variables);
    }

    @AllFieldsConstructor
    public FieldDeclaration(EnumSet<Modifier> modifiers, NodeList<AnnotationExpr> annotations, NodeList<VariableDeclarator> variables) {
        this(null, modifiers, annotations, variables);
    }

    /**
     * This constructor is used by the parser and is considered private.
     */
    @Generated("com.github.javaparser.generator.core.node.MainConstructorGenerator")
    public FieldDeclaration(TokenRange tokenRange, EnumSet<Modifier> modifiers, NodeList<AnnotationExpr> annotations, NodeList<VariableDeclarator> variables) {
        super(tokenRange, annotations);
        setModifiers(modifiers);
        setVariables(variables);
        customInitialization();
    }

    /**
     * Creates a {@link FieldDeclaration}.
     *
     * @param modifiers modifiers
     * @param type type
     * @param name field name
     */
    public FieldDeclaration(EnumSet<Modifier> modifiers, Type type, String name) {
        this(assertNotNull(modifiers), new VariableDeclarator(type, assertNotNull(name)));
    }

    @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);
    }

    /**
     * Return the modifiers of this member declaration.
     *
     * @return modifiers
     * @see Modifier
     */
    @Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
    public EnumSet<Modifier> getModifiers() {
        return modifiers;
    }

    @Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
    public NodeList<VariableDeclarator> getVariables() {
        return variables;
    }

    @Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
    public FieldDeclaration setModifiers(final EnumSet<Modifier> modifiers) {
        assertNotNull(modifiers);
        if (modifiers == this.modifiers) {
            return (FieldDeclaration) this;
        }
        notifyPropertyChange(ObservableProperty.MODIFIERS, this.modifiers, modifiers);
        this.modifiers = modifiers;
        return this;
    }

    @Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
    public FieldDeclaration setVariables(final NodeList<VariableDeclarator> variables) {
        assertNotNull(variables);
        if (variables == this.variables) {
            return (FieldDeclaration) this;
        }
        notifyPropertyChange(ObservableProperty.VARIABLES, this.variables, variables);
        if (this.variables != null)
            this.variables.setParentNode(null);
        this.variables = variables;
        setAsParentNodeOf(variables);
        return this;
    }

    /**
     * Create a getter for this field, <b>will only work if this field declares only 1 identifier and if this field is
     * already added to a ClassOrInterfaceDeclaration</b>
     *
     * @return the {@link MethodDeclaration} created
     * @throws IllegalStateException if there is more than 1 variable identifier or if this field isn't attached to a
     * class or enum
     */
    public MethodDeclaration createGetter() {
        if (getVariables().size() != 1)
            throw new IllegalStateException("You can use this only when the field declares only 1 variable name");
        Optional<ClassOrInterfaceDeclaration> parentClass = getAncestorOfType(ClassOrInterfaceDeclaration.class);
        Optional<EnumDeclaration> parentEnum = getAncestorOfType(EnumDeclaration.class);
        if (!(parentClass.isPresent() || parentEnum.isPresent()) || (parentClass.isPresent() && parentClass.get().isInterface()))
            throw new IllegalStateException("You can use this only when the field is attached to a class or an enum");
        VariableDeclarator variable = getVariable(0);
        String fieldName = variable.getNameAsString();
        String fieldNameUpper = fieldName.toUpperCase().substring(0, 1) + fieldName.substring(1, fieldName.length());
        final MethodDeclaration getter;
        getter = parentClass.map(clazz -> clazz.addMethod("get" + fieldNameUpper, PUBLIC)).orElseGet(() -> parentEnum.get().addMethod("get" + fieldNameUpper, PUBLIC));
        getter.setType(variable.getType());
        BlockStmt blockStmt = new BlockStmt();
        getter.setBody(blockStmt);
        blockStmt.addStatement(new ReturnStmt(fieldName));
        return getter;
    }

    /**
     * Create a setter for this field, <b>will only work if this field declares only 1 identifier and if this field is
     * already added to a ClassOrInterfaceDeclaration</b>
     *
     * @return the {@link MethodDeclaration} created
     * @throws IllegalStateException if there is more than 1 variable identifier or if this field isn't attached to a
     * class or enum
     */
    public MethodDeclaration createSetter() {
        if (getVariables().size() != 1)
            throw new IllegalStateException("You can use this only when the field declares only 1 variable name");
        Optional<ClassOrInterfaceDeclaration> parentClass = getAncestorOfType(ClassOrInterfaceDeclaration.class);
        Optional<EnumDeclaration> parentEnum = getAncestorOfType(EnumDeclaration.class);
        if (!(parentClass.isPresent() || parentEnum.isPresent()) || (parentClass.isPresent() && parentClass.get().isInterface()))
            throw new IllegalStateException("You can use this only when the field is attached to a class or an enum");
        VariableDeclarator variable = getVariable(0);
        String fieldName = variable.getNameAsString();
        String fieldNameUpper = fieldName.toUpperCase().substring(0, 1) + fieldName.substring(1, fieldName.length());
        final MethodDeclaration setter;
        setter = parentClass.map(clazz -> clazz.addMethod("set" + fieldNameUpper, PUBLIC)).orElseGet(() -> parentEnum.get().addMethod("set" + fieldNameUpper, PUBLIC));
        setter.setType(new VoidType());
        setter.getParameters().add(new Parameter(variable.getType(), fieldName));
        BlockStmt blockStmt2 = new BlockStmt();
        setter.setBody(blockStmt2);
        blockStmt2.addStatement(new AssignExpr(new NameExpr("this." + fieldName), new NameExpr(fieldName), Operator.ASSIGN));
        return setter;
    }

    public boolean isTransient() {
        return getModifiers().contains(TRANSIENT);
    }

    public boolean isVolatile() {
        return getModifiers().contains(VOLATILE);
    }

    public FieldDeclaration setTransient(boolean set) {
        return setModifier(TRANSIENT, set);
    }

    public FieldDeclaration setVolatile(boolean set) {
        return setModifier(VOLATILE, set);
    }

    @Override
    @Generated("com.github.javaparser.generator.core.node.RemoveMethodGenerator")
    public boolean remove(Node node) {
        if (node == null)
            return false;
        for (int i = 0; i < variables.size(); i++) {
            if (variables.get(i) == node) {
                variables.remove(i);
                return true;
            }
        }
        return super.remove(node);
    }

    @Override
    @Generated("com.github.javaparser.generator.core.node.CloneGenerator")
    public FieldDeclaration clone() {
        return (FieldDeclaration) accept(new CloneVisitor(), null);
    }

    @Override
    @Generated("com.github.javaparser.generator.core.node.GetMetaModelGenerator")
    public FieldDeclarationMetaModel getMetaModel() {
        return JavaParserMetaModel.fieldDeclarationMetaModel;
    }

    @Override
    @Generated("com.github.javaparser.generator.core.node.ReplaceMethodGenerator")
    public boolean replace(Node node, Node replacementNode) {
        if (node == null)
            return false;
        for (int i = 0; i < variables.size(); i++) {
            if (variables.get(i) == node) {
                variables.set(i, (VariableDeclarator) replacementNode);
                return true;
            }
        }
        return super.replace(node, replacementNode);
    }

    @Override
    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")
    public boolean isFieldDeclaration() {
        return true;
    }

    @Override
    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")
    public FieldDeclaration asFieldDeclaration() {
        return this;
    }

    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")
    public void ifFieldDeclaration(Consumer<FieldDeclaration> action) {
        action.accept(this);
    }

    @Override
    public ResolvedFieldDeclaration resolve() {
        return getSymbolResolver().resolveDeclaration(this, ResolvedFieldDeclaration.class);
    }

    @Override
    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")
    public Optional<FieldDeclaration> toFieldDeclaration() {
        return Optional.of(this);
    }
}