/*
 * Copyright 2002-2018 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
 *
 *      https://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.springframework.jdbc.core.metadata;

import javax.sql.DataSource;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.dao.DataAccessResourceFailureException;
import org.springframework.jdbc.support.JdbcUtils;
import org.springframework.jdbc.support.MetaDataAccessException;

/**
 * Factory used to create a {@link TableMetaDataProvider} implementation
 * based on the type of database being used.
 *
 * @author Thomas Risberg
 * @since 2.5
 */
public final class TableMetaDataProviderFactory {

	private static final Log logger = LogFactory.getLog(TableMetaDataProviderFactory.class);


	private TableMetaDataProviderFactory() {
	}


	/**
	 * Create a {@link TableMetaDataProvider} based on the database meta-data.
	 * @param dataSource used to retrieve meta-data
	 * @param context the class that holds configuration and meta-data
	 * @return instance of the TableMetaDataProvider implementation to be used
	 */
	public static TableMetaDataProvider createMetaDataProvider(DataSource dataSource, TableMetaDataContext context) {
		try {
			return (TableMetaDataProvider) JdbcUtils.extractDatabaseMetaData(dataSource, databaseMetaData -> {
				String databaseProductName =
						JdbcUtils.commonDatabaseName(databaseMetaData.getDatabaseProductName());
				boolean accessTableColumnMetaData = context.isAccessTableColumnMetaData();
				TableMetaDataProvider provider;

				if ("Oracle".equals(databaseProductName)) {
					provider = new OracleTableMetaDataProvider(
							databaseMetaData, context.isOverrideIncludeSynonymsDefault());
				}
				else if ("PostgreSQL".equals(databaseProductName)) {
					provider = new PostgresTableMetaDataProvider(databaseMetaData);
				}
				else if ("Apache Derby".equals(databaseProductName)) {
					provider = new DerbyTableMetaDataProvider(databaseMetaData);
				}
				else if ("HSQL Database Engine".equals(databaseProductName)) {
					provider = new HsqlTableMetaDataProvider(databaseMetaData);
				}
				else {
					provider = new GenericTableMetaDataProvider(databaseMetaData);
				}

				if (logger.isDebugEnabled()) {
					logger.debug("Using " + provider.getClass().getSimpleName());
				}
				provider.initializeWithMetaData(databaseMetaData);
				if (accessTableColumnMetaData) {
					provider.initializeWithTableColumnMetaData(databaseMetaData,
							context.getCatalogName(), context.getSchemaName(), context.getTableName());
				}
				return provider;
			});
		}
		catch (MetaDataAccessException ex) {
			throw new DataAccessResourceFailureException("Error retrieving database meta-data", ex);
		}
	}

}
