/* 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.persistence.entity;

import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.activiti.engine.ActivitiObjectNotFoundException;
import org.activiti.engine.impl.ExecutionQueryImpl;
import org.activiti.engine.impl.Page;
import org.activiti.engine.impl.ProcessInstanceQueryImpl;
import org.activiti.engine.impl.context.Context;
import org.activiti.engine.impl.interceptor.CommandContext;
import org.activiti.engine.impl.persistence.AbstractManager;
import org.activiti.engine.runtime.Execution;
import org.activiti.engine.runtime.ProcessInstance;


/**
 * @author Tom Baeyens
 */
public class ExecutionEntityManager extends AbstractManager {
  
  @SuppressWarnings("unchecked")
  public void deleteProcessInstancesByProcessDefinition(String processDefinitionId, String deleteReason, boolean cascade) {
    List<String> processInstanceIds = getDbSqlSession()
      .selectList("selectProcessInstanceIdsByProcessDefinitionId", processDefinitionId);
  
    for (String processInstanceId: processInstanceIds) {
      deleteProcessInstance(processInstanceId, deleteReason, cascade);
    }
    
    if (cascade) {
      Context
        .getCommandContext()
        .getHistoricProcessInstanceEntityManager()
        .deleteHistoricProcessInstanceByProcessDefinitionId(processDefinitionId);
    }
  }

  public void deleteProcessInstance(String processInstanceId, String deleteReason) {
    deleteProcessInstance(processInstanceId, deleteReason, false);
  }

  public void deleteProcessInstance(String processInstanceId, String deleteReason, boolean cascade) {
    ExecutionEntity execution = findExecutionById(processInstanceId);
    
    if(execution == null) {
      throw new ActivitiObjectNotFoundException("No process instance found for id '" + processInstanceId + "'", ProcessInstance.class);
    }
    
    CommandContext commandContext = Context.getCommandContext();
    commandContext
      .getTaskEntityManager()
      .deleteTasksByProcessInstanceId(processInstanceId, deleteReason, cascade);
    
    // delete the execution BEFORE we delete the history, otherwise we will produce orphan HistoricVariableInstance instances
    execution.deleteCascade(deleteReason);
    
    if (cascade) {
      commandContext
      .getHistoricProcessInstanceEntityManager()
      .deleteHistoricProcessInstanceById(processInstanceId);
    }
  }

  public ExecutionEntity findSubProcessInstanceBySuperExecutionId(String superExecutionId) {
    return (ExecutionEntity) getDbSqlSession().selectOne("selectSubProcessInstanceBySuperExecutionId", superExecutionId);
  }
  
  @SuppressWarnings("unchecked")
  public List<ExecutionEntity> findChildExecutionsByParentExecutionId(String parentExecutionId) {
    return getDbSqlSession().selectList("selectExecutionsByParentExecutionId", parentExecutionId);
  }
  
  @SuppressWarnings("unchecked")
  public List<ExecutionEntity> findChildExecutionsByProcessInstanceId(String processInstanceId) {
    return getDbSqlSession().selectList("selectExecutionsByProcessInstanceId", processInstanceId);
  }

  public ExecutionEntity findExecutionById(String executionId) {
    return (ExecutionEntity) getDbSqlSession().selectById(ExecutionEntity.class, executionId);
  }
  
  public long findExecutionCountByQueryCriteria(ExecutionQueryImpl executionQuery) {
    return (Long) getDbSqlSession().selectOne("selectExecutionCountByQueryCriteria", executionQuery);
  }

  @SuppressWarnings("unchecked")
  public List<ExecutionEntity> findExecutionsByQueryCriteria(ExecutionQueryImpl executionQuery, Page page) {
    return getDbSqlSession().selectList("selectExecutionsByQueryCriteria", executionQuery, page);
  }

  public long findProcessInstanceCountByQueryCriteria(ProcessInstanceQueryImpl executionQuery) {
    return (Long) getDbSqlSession().selectOne("selectProcessInstanceCountByQueryCriteria", executionQuery);
  }
  
  @SuppressWarnings("unchecked")
  public List<ProcessInstance> findProcessInstanceByQueryCriteria(ProcessInstanceQueryImpl executionQuery) {
    return getDbSqlSession().selectList("selectProcessInstanceByQueryCriteria", executionQuery);
  }
  
  @SuppressWarnings("unchecked")
  public List<ProcessInstance> findProcessInstanceAndVariablesByQueryCriteria(ProcessInstanceQueryImpl executionQuery) {
    // paging doesn't work for combining process instances and variables due to an outer join, so doing it in-memory
    if (executionQuery.getFirstResult() < 0 || executionQuery.getMaxResults() <= 0) {
      return Collections.EMPTY_LIST;
    }
    
    int firstResult = executionQuery.getFirstResult();
    int maxResults = executionQuery.getMaxResults();
    
    // setting max results, limit to 20000 results for performance reasons
    executionQuery.setMaxResults(20000);
    executionQuery.setFirstResult(0);
    
    List<ProcessInstance> instanceList = getDbSqlSession().selectList("selectProcessInstanceWithVariablesByQueryCriteria", executionQuery);
    
    if (instanceList != null && instanceList.size() > 0) {
      if (firstResult > 0) {
        if (firstResult <= instanceList.size()) {
          int toIndex = firstResult + Math.min(maxResults, instanceList.size() - firstResult);
          return instanceList.subList(firstResult, toIndex);
        } else {
          return Collections.EMPTY_LIST;
        }
      } else {
        int toIndex = Math.min(maxResults, instanceList.size());
        return instanceList.subList(0, toIndex);
      }
    }
    return Collections.EMPTY_LIST;
  }

  @SuppressWarnings("unchecked")
  public List<ExecutionEntity> findEventScopeExecutionsByActivityId(String activityRef, String parentExecutionId) {
    Map<String, String> parameters = new HashMap<String, String>();
    parameters.put("activityId", activityRef);
    parameters.put("parentExecutionId", parentExecutionId);
    return getDbSqlSession().selectList("selectExecutionsByParentExecutionId", parameters);
  }

  @SuppressWarnings("unchecked")
  public List<Execution> findExecutionsByNativeQuery(Map<String, Object> parameterMap, int firstResult, int maxResults) {
    return getDbSqlSession().selectListWithRawParameter("selectExecutionByNativeQuery", parameterMap, firstResult, maxResults);
  }

  @SuppressWarnings("unchecked")
  public List<ProcessInstance> findProcessInstanceByNativeQuery(Map<String, Object> parameterMap, int firstResult, int maxResults) {
    return getDbSqlSession().selectListWithRawParameter("selectExecutionByNativeQuery", parameterMap, firstResult, maxResults);
  }

  public long findExecutionCountByNativeQuery(Map<String, Object> parameterMap) {
    return (Long) getDbSqlSession().selectOne("selectExecutionCountByNativeQuery", parameterMap);
  }
  
  public void updateExecutionTenantIdForDeployment(String deploymentId, String newTenantId) {
  	HashMap<String, Object> params = new HashMap<String, Object>();
  	params.put("deploymentId", deploymentId);
  	params.put("tenantId", newTenantId);
  	getDbSqlSession().getSqlSession().update("updateExecutionTenantIdForDeployment", params);
  }

}