/*
 * Copyright 1999-2015 dangdang.com.
 * <p>
 * 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.
 * </p>
 */

package io.shardingjdbc.core.api;

import io.shardingjdbc.core.api.config.ShardingRuleConfiguration;
import io.shardingjdbc.core.jdbc.core.datasource.ShardingDataSource;
import io.shardingjdbc.core.yaml.sharding.YamlShardingRuleConfiguration;
import lombok.AccessLevel;
import lombok.NoArgsConstructor;
import org.yaml.snakeyaml.Yaml;
import org.yaml.snakeyaml.constructor.Constructor;

import javax.sql.DataSource;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.sql.SQLException;
import java.util.Collections;
import java.util.Map;
import java.util.Properties;

/**
 * Sharding data source factory.
 * 
 * @author zhangliang 
 */
@NoArgsConstructor(access = AccessLevel.PRIVATE)
public final class ShardingDataSourceFactory {
    
    /**
     * Create sharding data source.
     * 
     * @param dataSourceMap data source map
     * @param shardingRuleConfig rule configuration for databases and tables sharding
     * @return sharding data source
     * @throws SQLException SQL exception
     */
    public static DataSource createDataSource(final Map<String, DataSource> dataSourceMap, final ShardingRuleConfiguration shardingRuleConfig) throws SQLException {
        return new ShardingDataSource(shardingRuleConfig.build(dataSourceMap));
    }
    
    /**
     * Create sharding data source.
     * 
     * @param dataSourceMap data source map
     * @param shardingRuleConfig rule configuration for databases and tables sharding
     * @param props properties for data source
     * @return sharding data source
     * @throws SQLException SQL exception
     */
    public static DataSource createDataSource(final Map<String, DataSource> dataSourceMap, final ShardingRuleConfiguration shardingRuleConfig, final Properties props) throws SQLException {
        return new ShardingDataSource(shardingRuleConfig.build(dataSourceMap), props);
    }
    
    /**
     * Create sharding data source.
     *
     * @param yamlFile yaml file for rule configuration of databases and tables sharding with data sources
     * @return sharding data source
     * @throws SQLException SQL exception
     * @throws IOException IO exception
     */
    public static DataSource createDataSource(final File yamlFile) throws SQLException, IOException {
        YamlShardingRuleConfiguration config = unmarshal(yamlFile);
        return new ShardingDataSource(config.getShardingRule(Collections.<String, DataSource>emptyMap()), config.getProps());
    }
    
    /**
     * Create sharding data source.
     *
     * @param dataSourceMap data source map
     * @param yamlFile yaml file for rule configuration of databases and tables sharding without data sources
     * @return sharding data source
     * @throws SQLException SQL exception
     * @throws SQLException IO exception
     */
    public static DataSource createDataSource(final Map<String, DataSource> dataSourceMap, final File yamlFile) throws SQLException, IOException {
        YamlShardingRuleConfiguration config = unmarshal(yamlFile);
        return new ShardingDataSource(config.getShardingRule(dataSourceMap), config.getProps());
    }
    
    /**
     * Create sharding data source.
     *
     * @param yamlByteArray yaml byte array for rule configuration of databases and tables sharding with data sources
     * @return sharding data source
     * @throws SQLException SQL exception
     * @throws SQLException IO exception
     */
    public static DataSource createDataSource(final byte[] yamlByteArray) throws SQLException, IOException {
        YamlShardingRuleConfiguration config = unmarshal(yamlByteArray);
        return new ShardingDataSource(config.getShardingRule(Collections.<String, DataSource>emptyMap()), config.getProps());
    }
    
    /**
     * Create sharding data source.
     *
     * @param dataSourceMap data source map
     * @param yamlByteArray yaml byte array for rule configuration of databases and tables sharding without data sources
     * @return sharding data source
     * @throws SQLException SQL exception
     * @throws SQLException IO exception
     */
    public static DataSource createDataSource(final Map<String, DataSource> dataSourceMap, final byte[] yamlByteArray) throws SQLException, IOException {
        YamlShardingRuleConfiguration config = unmarshal(yamlByteArray);
        return new ShardingDataSource(config.getShardingRule(dataSourceMap), config.getProps());
    }
    
    private static YamlShardingRuleConfiguration unmarshal(final File yamlFile) throws IOException {
        try (
                FileInputStream fileInputStream = new FileInputStream(yamlFile);
                InputStreamReader inputStreamReader = new InputStreamReader(fileInputStream, "UTF-8")
        ) {
            return new Yaml(new Constructor(YamlShardingRuleConfiguration.class)).loadAs(inputStreamReader, YamlShardingRuleConfiguration.class);
        }
    }
    
    private static YamlShardingRuleConfiguration unmarshal(final byte[] yamlByteArray) throws IOException {
        return new Yaml(new Constructor(YamlShardingRuleConfiguration.class)).loadAs(new ByteArrayInputStream(yamlByteArray), YamlShardingRuleConfiguration.class);
    }
}