/*
 * Copyright © 2021 DataSQRL (contact@datasqrl.com)
 *
 * 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 com.datasqrl.util;

import com.datasqrl.config.EngineFactory;
import com.datasqrl.engine.IExecutionEngine;
import com.datasqrl.engine.database.DatabaseEngine;
import com.datasqrl.engine.database.QueryEngine;
import java.util.List;
import java.util.Set;
import java.util.stream.Stream;
import lombok.AccessLevel;
import lombok.NoArgsConstructor;

@NoArgsConstructor(access = AccessLevel.PRIVATE)
public final class EngineUtil {

  public static List<String> getAvailableDatabaseEngineNames(String... exclusions) {
    var exclusionSet = Set.of(exclusions);

    return getChildEngineFactories(DatabaseEngine.class)
        .map(EngineFactory::getEngineName)
        .filter(name -> !exclusionSet.contains(name))
        .toList();
  }

  public static List<String> getAvailableQueryEngineNames() {
    return getChildEngineFactories(QueryEngine.class).map(EngineFactory::getEngineName).toList();
  }

  public static Stream<EngineFactory> getChildEngineFactories(
      Class<? extends IExecutionEngine> parentEngineClass) {

    return ServiceLoaderDiscovery.getAll(EngineFactory.class).stream()
        .filter(factory -> parentEngineClass.isAssignableFrom(factory.getFactoryClass()));
  }
}
