/* 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.validation.validator.impl;

import java.util.List;

import org.activiti.bpmn.model.BpmnModel;
import org.activiti.bpmn.model.ImplementationType;
import org.activiti.bpmn.model.Interface;
import org.activiti.bpmn.model.Operation;
import org.activiti.bpmn.model.Process;
import org.activiti.bpmn.model.ServiceTask;
import org.activiti.validation.ValidationError;
import org.activiti.validation.validator.Problems;
import org.apache.commons.lang3.StringUtils;

/**
 * @author jbarrez
 */
public class ServiceTaskValidator extends ExternalInvocationTaskValidator {

	@Override
	protected void executeValidation(BpmnModel bpmnModel, Process process, List<ValidationError> errors) {
		List<ServiceTask> serviceTasks = process.findFlowElementsOfType(ServiceTask.class);
		for (ServiceTask serviceTask : serviceTasks) {
			verifyImplementation(process, serviceTask, errors);
			verifyType(process, serviceTask, errors);
			verifyResultVariableName(process, serviceTask, errors);
			verifyWebservice(bpmnModel, process, serviceTask, errors);
		}
			
	}

	protected void verifyImplementation(Process process, ServiceTask serviceTask, List<ValidationError> errors) {
	  if (!ImplementationType.IMPLEMENTATION_TYPE_CLASS.equalsIgnoreCase(serviceTask.getImplementationType())
	  		&& !ImplementationType.IMPLEMENTATION_TYPE_DELEGATEEXPRESSION.equalsIgnoreCase(serviceTask.getImplementationType())
	  		&& !ImplementationType.IMPLEMENTATION_TYPE_EXPRESSION.equalsIgnoreCase(serviceTask.getImplementationType())
	  		&& !ImplementationType.IMPLEMENTATION_TYPE_WEBSERVICE.equalsIgnoreCase(serviceTask.getImplementationType())
	  		&& StringUtils.isEmpty(serviceTask.getType())) {
	  	addError(errors, Problems.SERVICE_TASK_MISSING_IMPLEMENTATION, process, serviceTask, 
	  			"One of the attributes 'class', 'delegateExpression', 'type', 'operation', or 'expression' is mandatory on serviceTask.");
	  }
  }

	protected void verifyType(Process process, ServiceTask serviceTask, List<ValidationError> errors) {
	  if (StringUtils.isNotEmpty(serviceTask.getType())) {
	  	
	    if (!serviceTask.getType().equalsIgnoreCase("mail")
	    		&& !serviceTask.getType().equalsIgnoreCase("mule")
	    		&& !serviceTask.getType().equalsIgnoreCase("camel")
	    		&& !(serviceTask.getType().equalsIgnoreCase("shell"))) {
	    	addError(errors, Problems.SERVICE_TASK_INVALID_TYPE, process, serviceTask, "Invalid or unsupported service task type");
	    }
	    
	    if (serviceTask.getType().equalsIgnoreCase("mail")) {
	      validateFieldDeclarationsForEmail(process, serviceTask, serviceTask.getFieldExtensions(), errors);
	    } else if (serviceTask.getType().equalsIgnoreCase("shell")) {
	    	validateFieldDeclarationsForShell(process, serviceTask, serviceTask.getFieldExtensions(), errors);
	    }
	    
	  }
  }

	protected void verifyResultVariableName(Process process, ServiceTask serviceTask, List<ValidationError> errors) {
	  if (StringUtils.isNotEmpty(serviceTask.getResultVariableName())
	      && (ImplementationType.IMPLEMENTATION_TYPE_CLASS.equals(serviceTask.getImplementationType()) || 
	      		ImplementationType.IMPLEMENTATION_TYPE_DELEGATEEXPRESSION.equals(serviceTask.getImplementationType()))) {
	  	addError(errors, Problems.SERVICE_TASK_RESULT_VAR_NAME_WITH_DELEGATE,
	  			process, serviceTask, "'resultVariableName' not supported for service tasks using 'class' or 'delegateExpression");
	  }
  }

	protected void verifyWebservice(BpmnModel bpmnModel, Process process, ServiceTask serviceTask, List<ValidationError> errors) {
	  if (ImplementationType.IMPLEMENTATION_TYPE_WEBSERVICE.equalsIgnoreCase(serviceTask.getImplementationType()) && 
	        StringUtils.isNotEmpty(serviceTask.getOperationRef())) {
	  	
	  	boolean operationFound = false;
	  	if (bpmnModel.getInterfaces() != null && !bpmnModel.getInterfaces().isEmpty()) {
	  		for (Interface bpmnInterface : bpmnModel.getInterfaces()) {
	  			if (bpmnInterface.getOperations() != null && !bpmnInterface.getOperations().isEmpty()) {
	  				for (Operation operation : bpmnInterface.getOperations()) {
	  					if (operation.getId() != null && operation.getId().equals(serviceTask.getOperationRef())) {
	  						operationFound = true;
	  					}
	  				}
	  			}
	  		}
	  	}
	  	
	  	if (!operationFound) {
	  		addError(errors, Problems.SERVICE_TASK_WEBSERVICE_INVALID_OPERATION_REF, process, serviceTask, "Invalid operation reference");
	  	}
	  	
	  }
  }

}