/*
 * 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.maven.toolchain;

import javax.inject.Inject;
import javax.inject.Named;
import javax.inject.Singleton;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.maven.execution.MavenSession;
import org.apache.maven.plugin.descriptor.PluginDescriptor;
import org.apache.maven.project.MavenProject;
import org.apache.maven.toolchain.model.ToolchainModel;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import static java.util.Objects.requireNonNull;

/**
 * @author mkleint
 */
@Named
@Singleton
public class DefaultToolchainManager implements ToolchainManager {
    protected final Logger logger; // TODO this class is extended, needs refactoring

    final Map<String, ToolchainFactory> factories;

    @Inject
    public DefaultToolchainManager(Map<String, ToolchainFactory> factories) {
        this.factories = factories;
        this.logger = LoggerFactory.getLogger(DefaultToolchainManager.class);
    }

    /**
     * Ctor needed for UT.
     */
    DefaultToolchainManager(Map<String, ToolchainFactory> factories, Logger logger) {
        this.factories = factories;
        this.logger = requireNonNull(logger);
    }

    @Override
    public Toolchain getToolchainFromBuildContext(String type, MavenSession session) {
        Map<String, Object> context = retrieveContext(session);

        ToolchainModel model = (ToolchainModel) context.get(getStorageKey(type));

        if (model != null) {
            List<Toolchain> toolchains = selectToolchains(Collections.singletonList(model), type, null);

            if (!toolchains.isEmpty()) {
                return toolchains.get(0);
            }
        }

        return null;
    }

    @Override
    public List<Toolchain> getToolchains(MavenSession session, String type, Map<String, String> requirements) {
        List<ToolchainModel> models = session.getRequest().getToolchains().get(type);

        return selectToolchains(models, type, requirements);
    }

    private List<Toolchain> selectToolchains(
            List<ToolchainModel> models, String type, Map<String, String> requirements) {
        List<Toolchain> toolchains = new ArrayList<>();

        if (models != null) {
            ToolchainFactory fact = factories.get(type);

            if (fact == null) {
                logger.error(
                        "Missing toolchain factory for type: " + type + ". Possibly caused by misconfigured project.");
            } else {
                for (ToolchainModel model : models) {
                    try {
                        ToolchainPrivate toolchain = fact.createToolchain(model);
                        if (requirements == null || toolchain.matchesRequirements(requirements)) {
                            toolchains.add(toolchain);
                        }
                    } catch (MisconfiguredToolchainException ex) {
                        logger.error("Misconfigured toolchain.", ex);
                    }
                }
            }
        }
        return toolchains;
    }

    Map<String, Object> retrieveContext(MavenSession session) {
        Map<String, Object> context = null;

        if (session != null) {
            PluginDescriptor desc = new PluginDescriptor();
            desc.setGroupId(PluginDescriptor.getDefaultPluginGroupId());
            desc.setArtifactId(PluginDescriptor.getDefaultPluginArtifactId("toolchains"));

            MavenProject current = session.getCurrentProject();

            if (current != null) {
                // TODO why is this using the context
                context = session.getPluginContext(desc, current);
            }
        }

        return (context != null) ? context : new HashMap<>();
    }

    public static final String getStorageKey(String type) {
        return "toolchain-" + type; // NOI18N
    }
}
