/* 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.event;

import java.util.Map;

import org.activiti.engine.ActivitiException;
import org.activiti.engine.ActivitiObjectNotFoundException;
import org.activiti.engine.impl.context.Context;
import org.activiti.engine.impl.interceptor.CommandContext;
import org.activiti.engine.impl.persistence.deploy.DeploymentManager;
import org.activiti.engine.impl.persistence.entity.EventSubscriptionEntity;
import org.activiti.engine.impl.persistence.entity.ExecutionEntity;
import org.activiti.engine.impl.persistence.entity.ProcessDefinitionEntity;
import org.activiti.engine.impl.pvm.process.ActivityImpl;
import org.activiti.engine.repository.ProcessDefinition;



/**
 * @author Daniel Meyer
 * @author Joram Barrez
 */
public class SignalEventHandler extends AbstractEventHandler {
  
  public static final String EVENT_HANDLER_TYPE = "signal";

  public String getEventHandlerType() {
    return EVENT_HANDLER_TYPE;
  }
  
  @Override
  public void handleEvent(EventSubscriptionEntity eventSubscription, Object payload, CommandContext commandContext) {
  	if (eventSubscription.getExecutionId() != null) {
  		super.handleEvent(eventSubscription, payload, commandContext);
  	} else if (eventSubscription.getProcessDefinitionId() != null) {
  		// Start event
  		String processDefinitionId = eventSubscription.getProcessDefinitionId();
  		DeploymentManager deploymentCache = Context
           .getProcessEngineConfiguration()
           .getDeploymentManager();
         
  		ProcessDefinitionEntity processDefinition = deploymentCache.findDeployedProcessDefinitionById(processDefinitionId);
  		if (processDefinition == null) {
  			throw new ActivitiObjectNotFoundException("No process definition found for id '" + processDefinitionId + "'", ProcessDefinition.class);
  		}
  		if (processDefinition.isSuspended()) {
  			throw new ActivitiException("Could not handle signal: process definition with id: " + processDefinitionId + " is suspended");
  		}
  		
  		ActivityImpl startActivity = processDefinition.findActivity(eventSubscription.getActivityId());
  		if (startActivity == null) {
  			throw new ActivitiException("Could no handle signal: no start activity found with id " + eventSubscription.getActivityId());
  		}
  		ExecutionEntity processInstance = processDefinition.createProcessInstance(null, startActivity);
  		if (processInstance == null) {
  			throw new ActivitiException("Could not handle signal: no process instance started");
  		}
  		
  		if (payload != null) {
  			if (payload instanceof Map) {
  				Map<String, Object> variables = (Map<String, Object>) payload;
  				processInstance.setVariables(variables);
  			}
  		}
  		
  		processInstance.start();
  	} else {
  		throw new ActivitiException("Invalid signal handling: no execution nor process definition set");
  	}
  }

}