/*
 * Copyright 2016 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
 *
 *      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.springframework.batch.item.file.builder;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;

import org.junit.Test;

import org.springframework.batch.item.ExecutionContext;
import org.springframework.batch.item.file.FlatFileItemWriter;
import org.springframework.batch.item.file.transform.PassThroughLineAggregator;
import org.springframework.core.io.FileSystemResource;
import org.springframework.core.io.Resource;
import org.springframework.test.util.ReflectionTestUtils;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;

/**
 * @author Michael Minella
 */
public class FlatFileItemWriterBuilderTests {

	// reads the output file to check the result
	private BufferedReader reader;

	@Test(expected = IllegalArgumentException.class)
	public void testMissingLineAggregator() {
		new FlatFileItemWriterBuilder<Foo>()
				.build();
	}

	@Test
	public void test() throws Exception {

		Resource output = new FileSystemResource(File.createTempFile("foo", "txt"));

		FlatFileItemWriter<Foo> writer = new FlatFileItemWriterBuilder<Foo>()
				.name("foo")
				.resource(output)
				.lineSeparator("$")
				.lineAggregator(new PassThroughLineAggregator<>())
				.encoding("UTF-16LE")
				.headerCallback(writer1 -> writer1.append("HEADER"))
				.footerCallback(writer12 -> writer12.append("FOOTER"))
				.build();

		ExecutionContext executionContext = new ExecutionContext();

		writer.open(executionContext);

		writer.write(Arrays.asList(new Foo(1, 2, "3"), new Foo(4, 5, "6")));

		writer.close();

		assertEquals("HEADER$Foo{first=1, second=2, third='3'}$Foo{first=4, second=5, third='6'}$FOOTER", readLine("UTF-16LE", output));
	}

	@Test
	public void testFlags() throws Exception {

		Resource output = new FileSystemResource(File.createTempFile("foo", "txt"));

		FlatFileItemWriter<Foo> writer = new FlatFileItemWriterBuilder<Foo>()
				.name("foo")
				.resource(output)
				.shouldDeleteIfEmpty(true)
				.shouldDeleteIfExists(false)
				.saveState(false)
				.forceSync(true)
				.append(true)
				.transactional(false)
				.lineAggregator(new PassThroughLineAggregator<>())
				.build();

		assertFalse((Boolean) ReflectionTestUtils.getField(writer, "saveState"));
		assertTrue((Boolean) ReflectionTestUtils.getField(writer, "append"));
		assertFalse((Boolean) ReflectionTestUtils.getField(writer, "transactional"));
		assertTrue((Boolean) ReflectionTestUtils.getField(writer, "shouldDeleteIfEmpty"));
		assertFalse((Boolean) ReflectionTestUtils.getField(writer, "shouldDeleteIfExists"));
		assertTrue((Boolean) ReflectionTestUtils.getField(writer, "forceSync"));
	}

	private String readLine(String encoding, Resource outputFile ) throws IOException {

		if (reader == null) {
			reader = new BufferedReader(new InputStreamReader(outputFile.getInputStream(), encoding));
		}

		return reader.readLine();
	}

	public static class Foo {
		private int first;
		private int second;
		private String third;

		public Foo(int first, int second, String third) {
			this.first = first;
			this.second = second;
			this.third = third;
		}

		public int getFirst() {
			return first;
		}

		public void setFirst(int first) {
			this.first = first;
		}

		public int getSecond() {
			return second;
		}

		public void setSecond(int second) {
			this.second = second;
		}

		public String getThird() {
			return third;
		}

		public void setThird(String third) {
			this.third = third;
		}

		@Override
		public String toString() {
			return "Foo{" +
					"first=" + first +
					", second=" + second +
					", third='" + third + '\'' +
					'}';
		}
	}
}