/*
 * 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.iotdb.flink.tsfile;

import org.apache.flink.api.common.io.FileOutputFormat;
import org.apache.flink.core.fs.Path;
import org.apache.flink.runtime.util.HadoopUtils;
import org.apache.flink.util.Preconditions;
import org.apache.hadoop.conf.Configuration;
import org.apache.iotdb.flink.tsfile.util.TSFileConfigUtil;
import org.apache.iotdb.hadoop.fileSystem.HDFSOutput;
import org.apache.iotdb.tsfile.common.conf.TSFileConfig;
import org.apache.iotdb.tsfile.write.TsFileWriter;
import org.apache.iotdb.tsfile.write.schema.Schema;
import org.apache.iotdb.tsfile.write.writer.LocalTsFileOutput;
import org.apache.iotdb.tsfile.write.writer.TsFileOutput;

import javax.annotation.Nullable;
import java.io.FileOutputStream;
import java.io.IOException;
import java.lang.reflect.Field;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Optional;

/**
 * The abstract base class of the output formats which write data to TsFile.
 * @param <T> The input data type.
 */
public abstract class TsFileOutputFormat<T> extends FileOutputFormat<T> {

	protected Schema schema;
	@Nullable
	protected TSFileConfig config;

	protected transient Configuration hadoopConf = null;
	protected transient TsFileWriter writer = null;

	public TsFileOutputFormat(String path, Schema schema, TSFileConfig config) {
		super(path == null ? null : new Path(path));
		this.schema = Preconditions.checkNotNull(schema);
		this.config = config;
	}

	@Override
	public void configure(org.apache.flink.configuration.Configuration flinkConfiguration) {
		super.configure(flinkConfiguration);
		hadoopConf = HadoopUtils.getHadoopConfiguration(flinkConfiguration);
	}

	@Override
	public void open(int taskNumber, int numTasks) throws IOException {
		super.open(taskNumber, numTasks);
		if (config != null) {
			TSFileConfigUtil.setGlobalTSFileConfig(config);
		}
		// Use TsFile API to write instead of FSDataOutputStream.
		this.stream.close();
		Path actualFilePath = getAcutalFilePath();
		TsFileOutput out;
		try {
			if (actualFilePath.getFileSystem().isDistributedFS()) {
				// HDFS
				out = new HDFSOutput(
					new org.apache.hadoop.fs.Path(new URI(actualFilePath.getPath())), hadoopConf, true);
			} else {
				// Local File System
				out = new LocalTsFileOutput(new FileOutputStream(actualFilePath.getPath()));
			}
		} catch (URISyntaxException e) {
			throw new RuntimeException(e);
		}
		writer = new TsFileWriter(out, schema);
	}

	@Override
	public void close() throws IOException {
		super.close();
		writer.close();
		writer = null;
	}

	@Override
	protected String getDirectoryFileName(int taskNumber) {
		return super.getDirectoryFileName(taskNumber) + ".tsfile";
	}

	protected Path getAcutalFilePath() {
		try {
			Field field = FileOutputFormat.class.getDeclaredField("actualFilePath");
			field.setAccessible(true);
			return (Path) field.get(this);
		} catch (NoSuchFieldException | IllegalAccessException e) {
			throw new RuntimeException("Get actual file path failed!", e);
		}
	}

	public Schema getSchema() {
		return schema;
	}

	public Optional<TSFileConfig> getConfig() {
		return Optional.ofNullable(config);
	}
}