/*
    * 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.infra.database.core.type;
  
  import lombok.Getter;
  import org.apache.shardingsphere.infra.database.core.metadata.database.DialectDatabaseMetaData;
  import org.apache.shardingsphere.infra.database.core.spi.DatabaseTypedSPILoader;
  import org.apache.shardingsphere.infra.spi.ShardingSphereServiceLoader;
  
  import java.util.Collection;
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.stream.Collectors;
  
  /**
   * Database type registry.
   */
  public final class DatabaseTypeRegistry {
      
      private static final Map<DatabaseType, DialectDatabaseMetaData> REGISTERED_META_DATA = new ConcurrentHashMap<>();
      
      private final DatabaseType databaseType;
      
      @Getter
      private final DialectDatabaseMetaData dialectDatabaseMetaData;
      
      public DatabaseTypeRegistry(final DatabaseType databaseType) {
          this.databaseType = databaseType;
          if (!REGISTERED_META_DATA.containsKey(databaseType)) {
              REGISTERED_META_DATA.put(databaseType, DatabaseTypedSPILoader.getService(DialectDatabaseMetaData.class, databaseType));
          }
          dialectDatabaseMetaData = REGISTERED_META_DATA.get(databaseType);
      }
      
      /**
       * Get all branch database types.
       * 
       * @return all branch database types
       */
      public Collection<DatabaseType> getAllBranchDatabaseTypes() {
          return ShardingSphereServiceLoader.getServiceInstances(DatabaseType.class)
                  .stream().filter(each -> each.getTrunkDatabaseType().map(optional -> optional == databaseType).orElse(false)).collect(Collectors.toList());
      }
      
      /**
       * Get default schema name.
       *
       * @param databaseName database name
       * @return default schema name
       */
      public String getDefaultSchemaName(final String databaseName) {
          return dialectDatabaseMetaData.getDefaultSchema().orElseGet(() -> null == databaseName ? null : databaseName.toLowerCase());
      }
  }