/*
    * 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.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.annotation.JsonSerialize;
  import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
  import com.google.common.base.Equivalence;
  
  /**
   * Base class for patch operations taking a value in addition to a path.
   */
  abstract class PathValueOperation extends JsonPatchOperation {
  
      private static final Equivalence<JsonNode> EQUIVALENCE = JsonNumEquals.getInstance();
  
      @JsonSerialize
      private final JsonNode value;
  
      /**
       * Creates a new instance.
       *
       * @param op operation name
       * @param path affected path
       * @param value JSON value
       */
      PathValueOperation(final String op, final JsonPointer path, final JsonNode value) {
          super(op, path);
          this.value = value.deepCopy();
      }
  
      public JsonNode value() {
          return value;
      }
  
      JsonNode valueCopy() {
          return value.deepCopy();
      }
  
      void ensureEquivalence(JsonNode actual) {
          if (!EQUIVALENCE.equivalent(actual, value)) {
              throw new JsonPatchException("mismatching value at '" + path + "': " +
                                           actual + " (expected: " + value + ')');
          }
      }
  
      @Override
      public final void serialize(final JsonGenerator jgen,
                                  final SerializerProvider provider) throws IOException {
          jgen.writeStartObject();
          jgen.writeStringField("op", op);
          jgen.writeStringField("path", path.toString());
          jgen.writeFieldName("value");
          jgen.writeTree(value);
          jgen.writeEndObject();
      }
  
      @Override
      public final void serializeWithType(final JsonGenerator jgen,
                                          final SerializerProvider provider, final TypeSerializer typeSer)
              throws IOException {
          serialize(jgen, provider);
     }
 
     @Override
     public final String toString() {
         return "op: " + op + "; path: \"" + path + "\"; value: " + value;
     }
 }