/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.devtools.j2objc.types;

import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.Element;
import javax.lang.model.element.ElementKind;
import javax.lang.model.element.Modifier;
import javax.lang.model.element.Name;

/**
 * Base class for generated Element types.
 *
 * @author Keith Stanger
 */
public abstract class GeneratedElement implements Element {

  private final Name name;
  private final ElementKind kind;
  private final boolean synthetic;
  private Set<Modifier> modifiers = new HashSet<>();
  private final Element enclosingElement;
  private final List<AnnotationMirror> annotationMirrors = new ArrayList<>();

  protected GeneratedElement(String name, ElementKind kind, Element enclosingElement,
      boolean synthetic) {
    this.name = new NameImpl(name);
    this.kind = kind;
    this.synthetic = synthetic;
    this.enclosingElement = enclosingElement;
  }

  public String getName() {
    return name.toString();
  }

  @Override
  public ElementKind getKind() {
    return kind;
  }

  @Override
  public Name getSimpleName() {
    return name;
  }

  @Override
  public Set<Modifier> getModifiers() {
    return modifiers;
  }

  public GeneratedElement addModifiers(Modifier... newModifiers) {
    for (Modifier m : newModifiers) {
      modifiers.add(m);
    }
    return this;
  }

  public GeneratedElement addModifiers(Collection<? extends Modifier> newModifiers) {
    modifiers.addAll(newModifiers);
    return this;
  }

  public GeneratedElement removeModifiers(Modifier... modifiersToRemove) {
    for (Modifier m : modifiersToRemove) {
      modifiers.remove(m);
    }
    return this;
  }

  public boolean isSynthetic() {
    return synthetic;
  }

  @Override
  public Element getEnclosingElement() {
    return enclosingElement;
  }

  @Override
  public List<? extends Element> getEnclosedElements() {
    return Collections.emptyList();
  }

  @Override
  public List<? extends AnnotationMirror> getAnnotationMirrors() {
    return annotationMirrors;
  }

  public GeneratedElement addAnnotationMirrors(
      Collection<? extends AnnotationMirror> newAnnotations) {
    annotationMirrors.addAll(newAnnotations);
    return this;
  }

  @Override
  public String toString() {
    return name.toString();
  }

  @Override
  public <A extends Annotation> A getAnnotation(Class<A> annotationType) {
    return null;
  }

  @Override
  public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationType) {
    throw new AssertionError("not implemented");
  }

  /**
   * Concrete implementation for Javac's Name element.
   */
  protected static class NameImpl implements Name {

    private final String str;

    protected NameImpl(String str) {
      this.str = str;
    }

    @Override
    public int length() {
      return str.length();
    }

    @Override
    public char charAt(int index) {
      return str.charAt(index);
    }

    @Override
    public CharSequence subSequence(int start, int end) {
      return str.subSequence(start, end);
    }

    @Override
    public boolean contentEquals(CharSequence cs) {
      return str.equals(cs);
    }

    @Override
    public String toString() {
      return str;
    }
  };
}