/*
    * Copyright 2017 LINE Corporation
    *
    * LINE Corporation licenses this file to you 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:
    *
    *   https://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.
   */
  /*
   * Copyright (c) 2014, Francis Galiegue (fgaliegue@gmail.com)
   *
   * This software is dual-licensed under:
   *
   * - the Lesser General Public License (LGPL) version 3.0 or, at your option, any
   *   later version;
   * - the Apache Software License (ASL) version 2.0.
   *
   * The text of this file and of both licenses is available at the root of this
   * project or, if you have the jar distribution, in directory META-INF/, under
   * the names LGPL-3.0.txt and ASL-2.0.txt respectively.
   *
   * Direct link to the sources:
   *
   * - LGPL 3.0: https://www.gnu.org/licenses/lgpl-3.0.txt
   * - ASL 2.0: https://www.apache.org/licenses/LICENSE-2.0.txt
   */
  
  package com.linecorp.centraldogma.internal.jsonpatch;
  
  import java.io.IOException;
  
  import com.fasterxml.jackson.annotation.JsonCreator;
  import com.fasterxml.jackson.annotation.JsonProperty;
  import com.fasterxml.jackson.core.JsonGenerator;
  import com.fasterxml.jackson.core.JsonPointer;
  import com.fasterxml.jackson.databind.JsonNode;
  import com.fasterxml.jackson.databind.SerializerProvider;
  import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
  import com.fasterxml.jackson.databind.node.ArrayNode;
  import com.fasterxml.jackson.databind.node.MissingNode;
  import com.fasterxml.jackson.databind.node.ObjectNode;
  
  /**
   * JSON Path {@code remove} operation.
   *
   * <p>This operation only takes one pointer ({@code path}) as an argument. It
   * is an error condition if no JSON value exists at that pointer.</p>
   */
  public final class RemoveOperation extends JsonPatchOperation {
  
      @JsonCreator
      public RemoveOperation(@JsonProperty("path") final JsonPointer path) {
          super("remove", path);
      }
  
      @Override
      JsonNode apply(final JsonNode node) {
          if (path.toString().isEmpty()) {
              return MissingNode.getInstance();
          }
          ensureExistence(node);
  
          final JsonNode parentNode = node.at(path.head());
          final String raw = path.last().getMatchingProperty();
          if (parentNode.isObject()) {
              ((ObjectNode) parentNode).remove(raw);
          } else {
              ((ArrayNode) parentNode).remove(Integer.parseInt(raw));
          }
          return node;
      }
  
      @Override
      public void serialize(final JsonGenerator jgen,
                            final SerializerProvider provider) throws IOException {
          jgen.writeStartObject();
          jgen.writeStringField("op", "remove");
          jgen.writeStringField("path", path.toString());
          jgen.writeEndObject();
      }
  
      @Override
      public void serializeWithType(final JsonGenerator jgen,
                                    final SerializerProvider provider, final TypeSerializer typeSer)
              throws IOException {
          serialize(jgen, provider);
      }
  
      @Override
      public String toString() {
          return "op: " + op + "; path: \"" + path + '"';
      }
 }