/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.drill.exec.planner.sql.handlers;

import java.io.IOException;

import com.google.common.base.Strings;

import org.apache.calcite.tools.RelConversionException;
import org.apache.calcite.tools.ValidationException;
import org.apache.drill.exec.ops.QueryContext;
import org.apache.drill.exec.physical.PhysicalPlan;
import org.apache.drill.exec.planner.sql.DirectPlan;
import org.apache.drill.exec.planner.sql.parser.SqlUseSchema;
import org.apache.drill.exec.work.foreman.ForemanSetupException;
import org.apache.calcite.sql.SqlNode;

public class UseSchemaHandler extends AbstractSqlHandler {
  QueryContext context;

  public UseSchemaHandler(QueryContext context) {
    this.context = context;
  }

  @Override
  public PhysicalPlan getPlan(SqlNode sqlNode) throws ValidationException, RelConversionException, IOException, ForemanSetupException {
    final SqlUseSchema useSchema = unwrap(sqlNode, SqlUseSchema.class);
    final String newDefaultSchemaPath = useSchema.getSchema();

    context.getSession().setDefaultSchemaPath(newDefaultSchemaPath, context.getNewDefaultSchema());

    return DirectPlan.createDirectPlan(context, true,
        String.format("Default schema changed to [%s]", context.getSession().getDefaultSchemaPath()));
  }
}