/*
 * Copyright 2012-2017 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.boot.cli.compiler.grape;

import java.util.ArrayList;
import java.util.List;
import java.util.ServiceLoader;

import groovy.lang.GroovyClassLoader;
import org.apache.maven.repository.internal.MavenRepositorySystemUtils;
import org.eclipse.aether.DefaultRepositorySystemSession;
import org.eclipse.aether.RepositorySystem;
import org.eclipse.aether.connector.basic.BasicRepositoryConnectorFactory;
import org.eclipse.aether.impl.DefaultServiceLocator;
import org.eclipse.aether.internal.impl.DefaultRepositorySystem;
import org.eclipse.aether.repository.RemoteRepository;
import org.eclipse.aether.repository.RepositoryPolicy;
import org.eclipse.aether.spi.connector.RepositoryConnectorFactory;
import org.eclipse.aether.spi.connector.transport.TransporterFactory;
import org.eclipse.aether.spi.locator.ServiceLocator;
import org.eclipse.aether.transport.file.FileTransporterFactory;
import org.eclipse.aether.transport.http.HttpTransporterFactory;

/**
 * Utility class to create a pre-configured {@link AetherGrapeEngine}.
 *
 * @author Andy Wilkinson
 */
public abstract class AetherGrapeEngineFactory {

	public static AetherGrapeEngine create(GroovyClassLoader classLoader,
			List<RepositoryConfiguration> repositoryConfigurations,
			DependencyResolutionContext dependencyResolutionContext, boolean quiet) {
		RepositorySystem repositorySystem = createServiceLocator()
				.getService(RepositorySystem.class);
		DefaultRepositorySystemSession repositorySystemSession = MavenRepositorySystemUtils
				.newSession();
		ServiceLoader<RepositorySystemSessionAutoConfiguration> autoConfigurations = ServiceLoader
				.load(RepositorySystemSessionAutoConfiguration.class);
		for (RepositorySystemSessionAutoConfiguration autoConfiguration : autoConfigurations) {
			autoConfiguration.apply(repositorySystemSession, repositorySystem);
		}
		new DefaultRepositorySystemSessionAutoConfiguration()
				.apply(repositorySystemSession, repositorySystem);
		return new AetherGrapeEngine(classLoader, repositorySystem,
				repositorySystemSession, createRepositories(repositoryConfigurations),
				dependencyResolutionContext, quiet);
	}

	private static ServiceLocator createServiceLocator() {
		DefaultServiceLocator locator = MavenRepositorySystemUtils.newServiceLocator();
		locator.addService(RepositorySystem.class, DefaultRepositorySystem.class);
		locator.addService(RepositoryConnectorFactory.class,
				BasicRepositoryConnectorFactory.class);
		locator.addService(TransporterFactory.class, HttpTransporterFactory.class);
		locator.addService(TransporterFactory.class, FileTransporterFactory.class);
		return locator;
	}

	private static List<RemoteRepository> createRepositories(
			List<RepositoryConfiguration> repositoryConfigurations) {
		List<RemoteRepository> repositories = new ArrayList<>(
				repositoryConfigurations.size());
		for (RepositoryConfiguration repositoryConfiguration : repositoryConfigurations) {
			RemoteRepository.Builder builder = new RemoteRepository.Builder(
					repositoryConfiguration.getName(), "default",
					repositoryConfiguration.getUri().toASCIIString());

			if (!repositoryConfiguration.getSnapshotsEnabled()) {
				builder.setSnapshotPolicy(
						new RepositoryPolicy(false, RepositoryPolicy.UPDATE_POLICY_NEVER,
								RepositoryPolicy.CHECKSUM_POLICY_IGNORE));
			}
			repositories.add(builder.build());
		}
		return repositories;
	}

}
