/*
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * or in the "license" file accompanying this file. This file 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 software.amazon.neptune.csv2rdf;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.junit.jupiter.api.Assertions.assertTrue;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.nio.file.Paths;
import java.util.Collection;
import java.util.List;

import org.junit.jupiter.api.Test;

import software.amazon.neptune.csv2rdf.NeptunePropertyGraphElement.NeptuneCsvSetValuedUserDefinedProperty;
import software.amazon.neptune.csv2rdf.NeptunePropertyGraphElement.NeptuneCsvUserDefinedProperty;
import software.amazon.neptune.csv2rdf.NeptunePropertyGraphElement.NeptunePropertyGraphVertex;
import software.amazon.neptune.csv2rdf.NeptuneCsvUserDefinedColumn.DataType;

public class NeptuneCsvInputParserTest {

	@Test
	public void emptyCsvIsRejected() {

		File empty = Paths.get("src", "test", "inputParserTest", "empty.csv").toFile();
		Csv2RdfException exception = assertThrows(Csv2RdfException.class, () -> new NeptuneCsvInputParser(empty));
		assertEquals("No header column found in input CSV file!", exception.getMessage());
	}

	@Test
	public void validUtf8IsSuccessful() {

		File invalidUtf8 = Paths.get("src", "test", "inputParserTest", "valid-utf8.csv").toFile();

		try (NeptuneCsvInputParser parser = new NeptuneCsvInputParser(invalidUtf8)) {
			NeptuneCsvUserDefinedProperty property = ((NeptunePropertyGraphVertex) parser.next())
					.getUserDefinedProperties().get(0);
			assertEquals("Bärbel", ((NeptuneCsvSetValuedUserDefinedProperty) property).getValues().iterator().next());
		}
	}

	@Test
	public void invalidUtf8CharacterIsReplaced() {

		File invalidUtf8 = Paths.get("src", "test", "inputParserTest", "iso-8859-15-with-E4-8bit-character.csv")
				.toFile();

		try (NeptuneCsvInputParser parser = new NeptuneCsvInputParser(invalidUtf8)) {
			NeptuneCsvUserDefinedProperty property = ((NeptunePropertyGraphVertex) parser.next())
					.getUserDefinedProperties().get(0);
			assertEquals("B�rbel", ((NeptuneCsvSetValuedUserDefinedProperty) property).getValues().iterator().next());
		}
	}

	@Test
	public void missingFileIsRejected() {

		File notExistingFile = Paths.get("src", "test", "inputParserTest", "not-existing.csv").toFile();
		Csv2RdfException exception = assertThrows(Csv2RdfException.class,
				() -> new NeptuneCsvInputParser(notExistingFile));
		assertTrue(exception.getMessage()
				.matches("Error creating input stream for CSV file .*" + notExistingFile.getPath()));
	}

	@Test
	public void openFromInputStream() throws FileNotFoundException {

		File validUtf8 = Paths.get("src", "test", "inputParserTest", "valid-utf8.csv").toFile();
		FileInputStream ins = new FileInputStream(validUtf8);

		try (NeptuneCsvInputParser parser = new NeptuneCsvInputParser(ins)) {
			NeptuneCsvUserDefinedProperty property = ((NeptunePropertyGraphVertex) parser.next())
					.getUserDefinedProperties().get(0);
			assertEquals("Bärbel", ((NeptuneCsvSetValuedUserDefinedProperty) property).getValues().iterator().next());
		}
	}

	@Test
	public void escapedSemicolon() {

		File escapedSemi = Paths.get("src", "test", "inputParserTest", "escaped-semicolon.csv").toFile();
		try (NeptuneCsvInputParser parser = new NeptuneCsvInputParser(escapedSemi)) {

			NeptunePropertyGraphVertex v = (NeptunePropertyGraphVertex) parser.next();
			List<NeptuneCsvUserDefinedProperty> props = v.getUserDefinedProperties();

			Collection<String> namesValues = props.get(0).getValues();
			Collection<String> labels = v.getLabels();

			assertTrue(labels.contains("person;"));
			assertTrue(labels.contains("boss"));
			assertEquals(labels.size(), 2);
			assertEquals(namesValues.size(), 2);
			assertTrue(namesValues.contains("John;Smith"));
			assertTrue(namesValues.contains("Jane;Smith"));
		}
	}

	@Test
	public void escapedColonInHeader() {
		File escapedColon = Paths.get("src", "test", "inputParserTest", "colon-in-header.csv").toFile();
		try (NeptuneCsvInputParser parser = new NeptuneCsvInputParser(escapedColon)) {

			NeptunePropertyGraphVertex v = (NeptunePropertyGraphVertex) parser.next();
			List<NeptuneCsvUserDefinedProperty> props = v.getUserDefinedProperties();
			String propName1 = props.get(0).getName();
			String propName2 = props.get(1).getName();
			String propName3 = props.get(2).getName();
			String propName4 = props.get(3).getName();

			DataType dt1 = props.get(0).getDataType();
			DataType dt2 = props.get(1).getDataType();
			DataType dt3 = props.get(2).getDataType();
			DataType dt4 = props.get(3).getDataType();

			assertEquals("http://example.com/age", propName1);
			assertEquals("multi:backslash\\\\:header", propName2);
			assertEquals("noDataType:", propName3);
			assertEquals("having\\back\\slashes:end", propName4);

			assertEquals(DataType.INT, dt1);
			assertEquals(DataType.STRING, dt2);
			assertEquals(DataType.STRING, dt3);
			assertEquals(DataType.INT, dt4);
		}
	}
}