package eu.dnetlib.dhp.common;

import static org.junit.jupiter.api.Assertions.*;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

import org.apache.hadoop.conf.Configuration;
import org.junit.jupiter.api.Nested;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.io.TempDir;

public class HdfsSupportTest {

	@Nested
	class Remove {

		@Test
		void shouldThrowARuntimeExceptionOnError() {
			// when
			assertThrows(RuntimeException.class, () -> HdfsSupport.remove(null, new Configuration()));
		}

		@Test
		void shouldRemoveADirFromHDFS(@TempDir Path tempDir) {
			// when
			HdfsSupport.remove(tempDir.toString(), new Configuration());

			// then
			assertFalse(Files.exists(tempDir));
		}

		@Test
		void shouldRemoveAFileFromHDFS(@TempDir Path tempDir) throws IOException {
			// given
			Path file = Files.createTempFile(tempDir, "p", "s");

			// when
			HdfsSupport.remove(file.toString(), new Configuration());

			// then
			assertFalse(Files.exists(file));
		}
	}

	@Nested
	class ListFiles {

		@Test
		void shouldThrowARuntimeExceptionOnError() {
			// when
			assertThrows(RuntimeException.class, () -> HdfsSupport.listFiles(null, new Configuration()));
		}

		@Test
		void shouldListFilesLocatedInPath(@TempDir Path tempDir) throws IOException {
			Path subDir1 = Files.createTempDirectory(tempDir, "list_me");
			Path subDir2 = Files.createTempDirectory(tempDir, "list_me");

			// when
			List<String> paths = HdfsSupport.listFiles(tempDir.toString(), new Configuration());

			// then
			assertEquals(2, paths.size());
			List<String> expecteds = Arrays.stream(new String[] {
				subDir1.toString(), subDir2.toString()
			})
				.sorted()
				.collect(Collectors.toList());
			List<String> actuals = paths.stream().sorted().collect(Collectors.toList());
			assertTrue(actuals.get(0).contains(expecteds.get(0)));
			assertTrue(actuals.get(1).contains(expecteds.get(1)));
		}
	}
}