/*
 * 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 com.epam.dlab.module;

import com.epam.dlab.core.AdapterBase;
import com.epam.dlab.core.parser.CommonFormat;
import com.epam.dlab.exceptions.AdapterException;
import com.epam.dlab.model.aws.ReportLine;
import com.fasterxml.jackson.annotation.JsonClassDescription;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonTypeName;
import com.google.common.base.MoreObjects.ToStringHelper;
import org.bson.Document;

import javax.validation.constraints.NotNull;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.List;

/** The adapter for file system.
 */
@JsonTypeName(ModuleName.ADAPTER_FILE)
@JsonClassDescription(
	"File adapter.\n" +
	"Read source or write converted data to the file.\n" +
	"  - type: " + ModuleName.ADAPTER_FILE + "\n" +
	"    [writeHeader: <true | false>]  - write header of data to the adapterOut.\n" +
	"    file: <filename>               - the name of file."
	)
public class AdapterFile extends AdapterBase {

	/** The name of file. */
	@NotNull
	@JsonProperty
	private String file;

    
	/** Return the name of file. */
	public String getFile() {
		return file;
	}
	
	/** Set the name of file. */
	public void setFile(String file) {
		this.file = file;
	}
	
	
	/** Reader for adapter. */
	@JsonIgnore
	private BufferedReader reader;
	
	/** Writer for adapter. */
	@JsonIgnore
	private BufferedWriter writer;
	

	@Override
	public void open() throws AdapterException {
		try {
			if (getMode() == Mode.READ) {
				reader = new BufferedReader(new FileReader(file));
			} else if (getMode() == Mode.WRITE) {
				writer = new BufferedWriter(new FileWriter(file));
			} else {
				throw new AdapterException("Mode of adapter unknown or not defined. Set mode to " + Mode.READ + " or " + Mode.WRITE + ".");
			}
		} catch (Exception e) {
			throw new AdapterException("Cannot open file " + file + ". " + e.getLocalizedMessage(), e);
		}
	}

	@Override
	public void close() throws AdapterException {
		if (reader != null) {
			try {
				reader.close();
			} catch (IOException e) {
				throw new AdapterException("Cannot close file " + file + ". " + e.getLocalizedMessage(), e);
			} finally {
				reader = null;
			}
		}
		
		if (writer != null) {
			try {
				writer.close();
			} catch (IOException e) {
				throw new AdapterException("Cannot close file " + file + ". " + e.getLocalizedMessage(), e);
			} finally {
				writer = null;
			}
		}
	}

	@Override
	public String getEntryName() {
		return getFile();
	}

	@Override
	public String readLine() throws AdapterException {
		try {
			return reader.readLine();
		} catch (IOException e) {
			throw new AdapterException("Cannot read file " + file + ". " + e.getLocalizedMessage(), e);
		}
	}

	@Override
	public void writeHeader(List<String> header) throws AdapterException {
		try {
			writer.write(CommonFormat.rowToString(header));
			writer.write(System.lineSeparator());
		} catch (IOException e) {
			throw new AdapterException("Cannot write file " + file + ". " + e.getLocalizedMessage(), e);
		}
	}

	@Override
	public Document writeRow(ReportLine row) throws AdapterException {
		try {
			writer.write(CommonFormat.rowToString(row));
			writer.write(System.lineSeparator());
		} catch (IOException e) {
			throw new AdapterException("Cannot write file " + file + ". " + e.getLocalizedMessage(), e);
		}
		return null;
	}
	
	
	@Override
	public ToStringHelper toStringHelper(Object self) {
		return super.toStringHelper(self)
				.add("file", file);
	}
}