/* 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.rest.service.api.runtime.task;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.activiti.engine.ActivitiException;
import org.activiti.engine.ActivitiObjectNotFoundException;
import org.activiti.rest.service.api.RestResponseFactory;
import org.activiti.rest.service.api.engine.variable.RestVariable;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

/**
 * @author Frederik Heremans
 */
@RestController
public class TaskVariableDataResource extends TaskVariableBaseResource {

  @RequestMapping(value="/runtime/tasks/{taskId}/variables/{variableName}/data", method = RequestMethod.GET, produces="application/json")
  public @ResponseBody byte[] getVariableData(@PathVariable("taskId") String taskId, 
      @PathVariable("variableName") String variableName, @RequestParam(value="scope", required=false) String scope,
      HttpServletRequest request, HttpServletResponse response) {
    
    try {
      byte[] result = null;
      
      RestVariable variable = getVariableFromRequest(taskId, variableName, scope, true);
      if (RestResponseFactory.BYTE_ARRAY_VARIABLE_TYPE.equals(variable.getType())) {
        result = (byte[]) variable.getValue();
        response.setContentType("application/octet-stream");
        
      } else if(RestResponseFactory.SERIALIZABLE_VARIABLE_TYPE.equals(variable.getType())) {
        ByteArrayOutputStream buffer = new ByteArrayOutputStream();
        ObjectOutputStream outputStream = new ObjectOutputStream(buffer);
        outputStream.writeObject(variable.getValue());
        outputStream.close();
        result = buffer.toByteArray();
        response.setContentType("application/x-java-serialized-object");
        
      } else {
        throw new ActivitiObjectNotFoundException("The variable does not have a binary data stream.", null);
      }
      return result;
      
    } catch(IOException ioe) {
      // Re-throw IOException
      throw new ActivitiException("Unexpected error getting variable data", ioe);
    }
  }
}