/* 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 org.activiti.engine.impl.variable;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;



/**
 * @author Tijs Rademakers
 */
public class JsonType implements VariableType {
  
  private static final Logger logger = LoggerFactory.getLogger(JsonType.class);
  
  protected final int maxLength;
  protected ObjectMapper objectMapper = null;

  public JsonType(int maxLength, ObjectMapper objectMapper) {
    this.maxLength = maxLength;
    this.objectMapper = objectMapper;
  }

  public String getTypeName() {
    return "json";
  }

  public boolean isCachable() {
    return true;
  }

  public Object getValue(ValueFields valueFields) {
    JsonNode jsonValue = null;
    if (valueFields.getTextValue() != null && valueFields.getTextValue().length() > 0) {
      try {
        jsonValue = objectMapper.readTree(valueFields.getTextValue());
      } catch (Exception e) {
        logger.error("Error reading json variable " + valueFields.getName(), e);
      }
    }
    return jsonValue;
  }

  public void setValue(Object value, ValueFields valueFields) {
    valueFields.setTextValue(value != null ? value.toString() : null);
  }

  public boolean isAbleToStore(Object value) {
    if (value == null) {
      return true;
    }
    if (JsonNode.class.isAssignableFrom(value.getClass())) {
      JsonNode jsonValue = (JsonNode) value;
      return jsonValue.toString().length() <= maxLength;
    }
    return false;
  }
}