/*
    * 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.shardingsphere.sqlfederation.optimizer.metadata.schema;
  
  import com.cedarsoftware.util.CaseInsensitiveMap;
  import lombok.Getter;
  import org.apache.calcite.adapter.java.JavaTypeFactory;
  import org.apache.calcite.rel.type.RelDataType;
  import org.apache.calcite.rel.type.RelDataTypeImpl;
  import org.apache.calcite.schema.Table;
  import org.apache.calcite.schema.impl.AbstractSchema;
  import org.apache.calcite.schema.impl.ViewTable;
  import org.apache.shardingsphere.infra.database.core.type.DatabaseType;
  import org.apache.shardingsphere.infra.metadata.database.schema.model.ShardingSphereSchema;
  import org.apache.shardingsphere.infra.metadata.database.schema.model.ShardingSphereTable;
  import org.apache.shardingsphere.infra.metadata.database.schema.model.ShardingSphereView;
  import org.apache.shardingsphere.sqlfederation.optimizer.metadata.util.SQLFederationDataTypeUtils;
  import org.apache.shardingsphere.sqlfederation.optimizer.statistic.SQLFederationStatistic;
  
  import java.util.Collections;
  import java.util.Map;
  
  /**
   * SQL federation schema.
   */
  @Getter
  public final class SQLFederationSchema extends AbstractSchema {
      
      private final String name;
      
      private final Map<String, Table> tableMap;
      
      public SQLFederationSchema(final String schemaName, final ShardingSphereSchema schema, final DatabaseType protocolType, final JavaTypeFactory javaTypeFactory) {
          name = schemaName;
          tableMap = createTableMap(schema, protocolType, javaTypeFactory);
      }
      
      private Map<String, Table> createTableMap(final ShardingSphereSchema schema, final DatabaseType protocolType, final JavaTypeFactory javaTypeFactory) {
          Map<String, Table> result = new CaseInsensitiveMap<>(schema.getTables().size(), 1F);
          for (ShardingSphereTable each : schema.getTables().values()) {
              if (schema.containsView(each.getName())) {
                  result.put(each.getName(), getViewTable(schema, each, protocolType, javaTypeFactory));
              } else {
                  // TODO implement table statistic logic after using custom operators
                  result.put(each.getName(), new SQLFederationTable(each, new SQLFederationStatistic(), protocolType));
              }
          }
          return result;
      }
      
      private ViewTable getViewTable(final ShardingSphereSchema schema, final ShardingSphereTable table, final DatabaseType protocolType, final JavaTypeFactory javaTypeFactory) {
          RelDataType relDataType = SQLFederationDataTypeUtils.createRelDataType(table, protocolType, javaTypeFactory);
          ShardingSphereView view = schema.getView(table.getName());
          return new ViewTable(javaTypeFactory.getJavaClass(relDataType), RelDataTypeImpl.proto(relDataType), view.getViewDefinition(), Collections.emptyList(), Collections.emptyList());
      }
  }