/*
 * 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.flink.table.client.cli;

import org.apache.flink.table.client.cli.SqlCommandParser.SqlCommand;
import org.apache.flink.table.client.cli.SqlCommandParser.SqlCommandCall;

import org.junit.Test;

import java.util.Optional;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.fail;

/**
 * Tests for {@link SqlCommandParser}.
 */
public class SqlCommandParserTest {

	@Test
	public void testCommands() {
		testValidSqlCommand("QUIT;", new SqlCommandCall(SqlCommand.QUIT));
		testValidSqlCommand("eXiT", new SqlCommandCall(SqlCommand.QUIT));
		testValidSqlCommand("CLEAR", new SqlCommandCall(SqlCommand.CLEAR));
		testValidSqlCommand("SHOW TABLES", new SqlCommandCall(SqlCommand.SHOW_TABLES));
		testValidSqlCommand("  SHOW   TABLES   ", new SqlCommandCall(SqlCommand.SHOW_TABLES));
		testValidSqlCommand("SHOW FUNCTIONS", new SqlCommandCall(SqlCommand.SHOW_FUNCTIONS));
		testValidSqlCommand("  SHOW    FUNCTIONS   ", new SqlCommandCall(SqlCommand.SHOW_FUNCTIONS));
		testValidSqlCommand("DESCRIBE MyTable", new SqlCommandCall(SqlCommand.DESCRIBE, new String[]{"MyTable"}));
		testValidSqlCommand("DESCRIBE         MyTable     ", new SqlCommandCall(SqlCommand.DESCRIBE, new String[]{"MyTable"}));
		testInvalidSqlCommand("DESCRIBE  "); // no table name
		testValidSqlCommand(
			"EXPLAIN SELECT complicated FROM table",
			new SqlCommandCall(SqlCommand.EXPLAIN, new String[]{"SELECT complicated FROM table"}));
		testInvalidSqlCommand("EXPLAIN  "); // no query
		testValidSqlCommand(
			"SELECT complicated FROM table",
			new SqlCommandCall(SqlCommand.SELECT, new String[]{"SELECT complicated FROM table"}));
		testValidSqlCommand(
			"   SELECT  complicated FROM table    ",
			new SqlCommandCall(SqlCommand.SELECT, new String[]{"SELECT  complicated FROM table"}));
		testValidSqlCommand(
			"INSERT INTO other SELECT 1+1",
			new SqlCommandCall(SqlCommand.INSERT_INTO, new String[]{"INSERT INTO other SELECT 1+1"}));
		testValidSqlCommand(
			"CREATE VIEW x AS SELECT 1+1",
			new SqlCommandCall(SqlCommand.CREATE_VIEW, new String[]{"CREATE VIEW x AS SELECT 1+1", "x", "SELECT 1+1"}));
		testValidSqlCommand(
			"CREATE   VIEW    MyTable   AS     SELECT 1+1 FROM y",
			new SqlCommandCall(SqlCommand.CREATE_VIEW, new String[]{"CREATE   VIEW    MyTable   AS     SELECT 1+1 FROM y", "MyTable", "SELECT 1+1 FROM y"}));
		testInvalidSqlCommand("CREATE VIEW x SELECT 1+1"); // missing AS
		testValidSqlCommand("DROP VIEW MyTable", new SqlCommandCall(SqlCommand.DROP_VIEW, new String[]{"MyTable"}));
		testValidSqlCommand("DROP VIEW  MyTable", new SqlCommandCall(SqlCommand.DROP_VIEW, new String[]{"MyTable"}));
		testInvalidSqlCommand("DROP VIEW");
		testValidSqlCommand("SET", new SqlCommandCall(SqlCommand.SET));
		testValidSqlCommand("SET x=y", new SqlCommandCall(SqlCommand.SET, new String[] {"x", "y"}));
		testValidSqlCommand("SET    x  = y", new SqlCommandCall(SqlCommand.SET, new String[] {"x", " y"}));
		testValidSqlCommand("reset;", new SqlCommandCall(SqlCommand.RESET));
		testValidSqlCommand("source /my/file", new SqlCommandCall(SqlCommand.SOURCE, new String[] {"/my/file"}));
		testInvalidSqlCommand("source"); // missing path
	}

	private void testInvalidSqlCommand(String stmt) {
		final Optional<SqlCommandCall> actualCall = SqlCommandParser.parse(stmt);
		if (actualCall.isPresent()) {
			fail();
		}
	}

	private void testValidSqlCommand(String stmt, SqlCommandCall expectedCall) {
		final Optional<SqlCommandCall> actualCall = SqlCommandParser.parse(stmt);
		if (!actualCall.isPresent()) {
			fail();
		}
		assertEquals(expectedCall, actualCall.get());
	}
}