/**
    *    Copyright 2009-2015 the original author or authors.
    *
    *    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.apache.ibatis.executor.statement;
  
  import java.sql.Connection;
  import java.sql.SQLException;
  import java.sql.Statement;
  
  import org.apache.ibatis.executor.ErrorContext;
  import org.apache.ibatis.executor.Executor;
  import org.apache.ibatis.executor.ExecutorException;
  import org.apache.ibatis.executor.keygen.KeyGenerator;
  import org.apache.ibatis.executor.parameter.ParameterHandler;
  import org.apache.ibatis.executor.resultset.ResultSetHandler;
  import org.apache.ibatis.mapping.BoundSql;
  import org.apache.ibatis.mapping.MappedStatement;
  import org.apache.ibatis.reflection.factory.ObjectFactory;
  import org.apache.ibatis.session.Configuration;
  import org.apache.ibatis.session.ResultHandler;
  import org.apache.ibatis.session.RowBounds;
  import org.apache.ibatis.type.TypeHandlerRegistry;
  
  /**
   * @author Clinton Begin
   */
  public abstract class BaseStatementHandler implements StatementHandler {
  
    protected final Configuration configuration;
    protected final ObjectFactory objectFactory;
    protected final TypeHandlerRegistry typeHandlerRegistry;
    protected final ResultSetHandler resultSetHandler;
    protected final ParameterHandler parameterHandler;
  
    protected final Executor executor;
    protected final MappedStatement mappedStatement;
    protected final RowBounds rowBounds;
  
    protected BoundSql boundSql;
  
    protected BaseStatementHandler(Executor executor, MappedStatement mappedStatement, Object parameterObject, RowBounds rowBounds, ResultHandler resultHandler, BoundSql boundSql) {
      this.configuration = mappedStatement.getConfiguration();
      this.executor = executor;
      this.mappedStatement = mappedStatement;
      this.rowBounds = rowBounds;
  
      this.typeHandlerRegistry = configuration.getTypeHandlerRegistry();
      this.objectFactory = configuration.getObjectFactory();
  
      if (boundSql == null) { // issue #435, get the key before calculating the statement
        generateKeys(parameterObject);
        boundSql = mappedStatement.getBoundSql(parameterObject);
      }
  
      this.boundSql = boundSql;
  
      this.parameterHandler = configuration.newParameterHandler(mappedStatement, parameterObject, boundSql);
      this.resultSetHandler = configuration.newResultSetHandler(executor, mappedStatement, rowBounds, parameterHandler, resultHandler, boundSql);
    }
  
    @Override
    public BoundSql getBoundSql() {
      return boundSql;
    }
  
    @Override
    public ParameterHandler getParameterHandler() {
      return parameterHandler;
    }
  
    @Override
    public Statement prepare(Connection connection) throws SQLException {
      ErrorContext.instance().sql(boundSql.getSql());
      Statement statement = null;
      try {
        statement = instantiateStatement(connection);
        setStatementTimeout(statement);
        setFetchSize(statement);
        return statement;
      } catch (SQLException e) {
        closeStatement(statement);
        throw e;
      } catch (Exception e) {
        closeStatement(statement);
        throw new ExecutorException("Error preparing statement.  Cause: " + e, e);
      }
    }
 
   protected abstract Statement instantiateStatement(Connection connection) throws SQLException;
 
   protected void setStatementTimeout(Statement stmt) throws SQLException {
     Integer timeout = mappedStatement.getTimeout();
     Integer defaultTimeout = configuration.getDefaultStatementTimeout();
     if (timeout != null) {
       stmt.setQueryTimeout(timeout);
     } else if (defaultTimeout != null) {
       stmt.setQueryTimeout(defaultTimeout);
     }
   }
 
   protected void setFetchSize(Statement stmt) throws SQLException {
     Integer fetchSize = mappedStatement.getFetchSize();
     if (fetchSize != null) {
       stmt.setFetchSize(fetchSize);
       return;
     }
     Integer defaultFetchSize = configuration.getDefaultFetchSize();
     if (defaultFetchSize != null) {
       stmt.setFetchSize(defaultFetchSize);
     }
   }
 
   protected void closeStatement(Statement statement) {
     try {
       if (statement != null) {
         statement.close();
       }
     } catch (SQLException e) {
       //ignore
     }
   }
 
   protected void generateKeys(Object parameter) {
     KeyGenerator keyGenerator = mappedStatement.getKeyGenerator();
     ErrorContext.instance().store();
     keyGenerator.processBefore(executor, mappedStatement, null, parameter);
     ErrorContext.instance().recall();
   }
 
 }