package org.apache.maven.lifecycle.mapping;

/*
 * 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.
 */

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

import static java.util.stream.Collectors.toMap;

/**
 * DefaultLifecycleMapping
 */
public class DefaultLifecycleMapping
    implements LifecycleMapping
{

    private List<Lifecycle> lifecycles;

    private Map<String, Lifecycle> lifecycleMap;

    /** @deprecated use lifecycles instead */
    private Map<String, LifecyclePhase> phases;

    /**
     * Default ctor for plexus compatibility: lifecycles are most commonly defined in Plexus XML, that does field
     * injection. Still, for Plexus to be able to instantiate this class, default ctor is needed.
     *
     * @deprecated Should not be used in Java code.
     */
    @Deprecated
    public DefaultLifecycleMapping()
    {
    }

    /**
     * Ctor to be used in Java code/providers.
     */
    public DefaultLifecycleMapping( final List<Lifecycle> lifecycles )
    {
        this.lifecycleMap = Collections.unmodifiableMap(
                lifecycles.stream().collect( toMap( Lifecycle::getId, l -> l ) )
        );
    }

    /**
     * Plexus: Populates the lifecycle map from the injected list of lifecycle mappings (if not already done).
     */
    private void initLifecycleMap()
    {
        if ( lifecycleMap == null )
        {
            lifecycleMap = new HashMap<>();

            if ( lifecycles != null )
            {
                for ( Lifecycle lifecycle : lifecycles )
                {
                    lifecycleMap.put( lifecycle.getId(), lifecycle );
                }
            }
            else
            {
                /*
                 * NOTE: This is to provide a migration path for implementors of the legacy API which did not know about
                 * getLifecycles().
                 */

                String[] lifecycleIds = { "default", "clean", "site" };

                for ( String lifecycleId : lifecycleIds )
                {
                    Map<String, LifecyclePhase> phases = getLifecyclePhases( lifecycleId );
                    if ( phases != null )
                    {
                        Lifecycle lifecycle = new Lifecycle();

                        lifecycle.setId( lifecycleId );
                        lifecycle.setLifecyclePhases( phases );

                        lifecycleMap.put( lifecycleId, lifecycle );
                    }
                }
            }
        }
    }

    @Override
    public Map<String, Lifecycle> getLifecycles()
    {
        initLifecycleMap();

        return lifecycleMap;
    }

    @Deprecated
    @Override
    public List<String> getOptionalMojos( String lifecycle )
    {
        return null;
    }

    private Map<String, LifecyclePhase> getLifecyclePhases( String lifecycle )
    {
        initLifecycleMap();

        Lifecycle lifecycleMapping = lifecycleMap.get( lifecycle );

        if ( lifecycleMapping != null )
        {
            return lifecycleMapping.getLifecyclePhases();
        }
        else if ( "default".equals( lifecycle ) )
        {
            return phases;
        }
        else
        {
            return null;
        }
    }

    @Deprecated
    @Override
    public Map<String, String> getPhases( String lifecycle )
    {
        return LifecyclePhase.toLegacyMap( getLifecyclePhases( lifecycle ) );
    }
}