package org.apache.archiva.maven.scheduler.indexing;

/*
 * 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 org.apache.archiva.indexer.ArchivaIndexingContext;
import org.apache.archiva.indexer.UnsupportedBaseContextException;
import org.apache.archiva.components.taskqueue.Task;
import org.apache.archiva.components.taskqueue.execution.TaskExecutionException;
import org.apache.archiva.components.taskqueue.execution.TaskExecutor;
import org.apache.archiva.repository.ManagedRepository;
import org.apache.archiva.repository.features.IndexCreationFeature;
import org.apache.archiva.scheduler.indexing.ArtifactIndexingTask;
import org.apache.maven.index.ArtifactContext;
import org.apache.maven.index.ArtifactContextProducer;
import org.apache.maven.index.DefaultScannerListener;
import org.apache.maven.index.FlatSearchRequest;
import org.apache.maven.index.FlatSearchResponse;
import org.apache.maven.index.Indexer;
import org.apache.maven.index.IndexerEngine;
import org.apache.maven.index.MAVEN;
import org.apache.maven.index.Scanner;
import org.apache.maven.index.ScanningRequest;
import org.apache.maven.index.ScanningResult;
import org.apache.maven.index.context.IndexingContext;
import org.apache.maven.index.expr.SourcedSearchExpression;
import org.apache.maven.index.packer.IndexPacker;
import org.apache.maven.index.packer.IndexPackingRequest;
import org.apache.maven.index_shaded.lucene.search.BooleanClause;
import org.apache.maven.index_shaded.lucene.search.BooleanQuery;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;

import javax.inject.Inject;
import java.io.IOException;
import java.nio.file.Path;

/**
 * ArchivaIndexingTaskExecutor Executes all indexing tasks. Adding, updating and removing artifacts from the index are
 * all performed by this executor. Add and update artifact in index tasks are added in the indexing task queue by the
 * NexusIndexerConsumer while remove artifact from index tasks are added by the LuceneCleanupRemoveIndexedConsumer.
 */
@Service( "taskExecutor#indexing" )
public class ArchivaIndexingTaskExecutor
    implements TaskExecutor
{
    private Logger log = LoggerFactory.getLogger( ArchivaIndexingTaskExecutor.class );

    @Inject
    private IndexPacker indexPacker;

    @Inject
    private ArtifactContextProducer artifactContextProducer;

    @Inject
    private Indexer indexer;

    @Inject
    private Scanner scanner;

    @Inject
    IndexerEngine indexerEngine;

    /**
     * depending on current {@link Task} you have.
     * If {@link org.apache.archiva.scheduler.indexing.ArtifactIndexingTask.Action#FINISH} && isExecuteOnEntireRepo:
     * repository will be scanned.
     *
     * @param task
     * @throws TaskExecutionException
     */
    @Override
    public void executeTask( Task task )
        throws TaskExecutionException
    {
        ArtifactIndexingTask indexingTask = (ArtifactIndexingTask) task;

        ManagedRepository repository = indexingTask.getRepository( );
        ArchivaIndexingContext archivaContext = indexingTask.getContext( );
        IndexingContext context = null;
        try
        {
            context = archivaContext.getBaseContext( IndexingContext.class );
        }
        catch ( UnsupportedBaseContextException e )
        {
            throw new TaskExecutionException( "Bad repository type.", e );
        }

        if ( ArtifactIndexingTask.Action.FINISH.equals( indexingTask.getAction( ) )
            && indexingTask.isExecuteOnEntireRepo( ) )
        {
            long start = System.currentTimeMillis( );
            try
            {
                context.updateTimestamp( );
                DefaultScannerListener listener = new DefaultScannerListener( context, indexerEngine, true, null );
                ScanningRequest request = new ScanningRequest( context, listener );
                ScanningResult result = scanner.scan( request );
                if ( result.hasExceptions( ) )
                {
                    log.error( "Exceptions occured during index scan of " + context.getId( ) );
                    result.getExceptions( ).stream( ).map( e -> e.getMessage( ) ).distinct( ).limit( 5 ).forEach(
                        s -> log.error( "Message: " + s )
                    );
                }
            }
            catch ( IOException e )
            {
                log.error( "Error during context scan {}: {}", context.getId( ), context.getIndexDirectory( ) );
            }
            long end = System.currentTimeMillis( );
            log.info( "indexed maven repository: {}, onlyUpdate: {}, time {} ms", repository.getId( ),
                indexingTask.isOnlyUpdate( ), ( end - start ) );
            log.debug( "Finishing indexing task on repo: {}", repository.getId( ) );
            finishIndexingTask( indexingTask, repository, context );
        }
        else
        {
            // create context if not a repo scan request
            if ( !indexingTask.isExecuteOnEntireRepo( ) )
            {
                try
                {
                    log.debug( "Creating indexing context on resource: {}", //
                        ( indexingTask.getResourceFile( ) == null
                            ? "none"
                            : indexingTask.getResourceFile( ) ) );
                    archivaContext = repository.getIndexingContext( );
                    context = archivaContext.getBaseContext( IndexingContext.class );
                }
                catch ( UnsupportedBaseContextException e )
                {
                    log.error( "Error occurred while creating context: {}", e.getMessage( ) );
                    throw new TaskExecutionException( "Error occurred while creating context: " + e.getMessage( ), e );
                }
            }

            if ( context == null || context.getIndexDirectory( ) == null )
            {
                throw new TaskExecutionException( "Trying to index an artifact but the context is already closed" );
            }

            try
            {
                Path artifactFile = indexingTask.getResourceFile( );
                if ( artifactFile == null )
                {
                    log.debug( "no artifact pass in indexing task so skip it" );
                }
                else
                {
                    ArtifactContext ac = artifactContextProducer.getArtifactContext( context, artifactFile.toFile( ) );

                    if ( ac != null )
                    {
                        // MRM-1779 pom must be indexed too
                        // TODO make that configurable?
                        if ( artifactFile.getFileName( ).toString( ).endsWith( ".pom" ) )
                        {
                            ac.getArtifactInfo( ).setFileExtension( "pom" );
                            ac.getArtifactInfo( ).setPackaging( "pom" );
                            ac.getArtifactInfo( ).setClassifier( "pom" );
                        }
                        if ( indexingTask.getAction( ).equals( ArtifactIndexingTask.Action.ADD ) )
                        {
                            //IndexSearcher s = context.getIndexSearcher();
                            //String uinfo = ac.getArtifactInfo().getUinfo();
                            //TopDocs d = s.search( new TermQuery( new Term( ArtifactInfo.UINFO, uinfo ) ), 1 );

                            BooleanQuery.Builder qb = new BooleanQuery.Builder();
                            qb.add( indexer.constructQuery( MAVEN.GROUP_ID, new SourcedSearchExpression(
                                ac.getArtifactInfo( ).getGroupId( ) ) ), BooleanClause.Occur.MUST );
                            qb.add( indexer.constructQuery( MAVEN.ARTIFACT_ID, new SourcedSearchExpression(
                                ac.getArtifactInfo( ).getArtifactId( ) ) ), BooleanClause.Occur.MUST );
                            qb.add( indexer.constructQuery( MAVEN.VERSION, new SourcedSearchExpression(
                                ac.getArtifactInfo( ).getVersion( ) ) ), BooleanClause.Occur.MUST );
                            if ( ac.getArtifactInfo( ).getClassifier( ) != null )
                            {
                                qb.add( indexer.constructQuery( MAVEN.CLASSIFIER, new SourcedSearchExpression(
                                    ac.getArtifactInfo( ).getClassifier( ) ) ), BooleanClause.Occur.MUST );
                            }
                            if ( ac.getArtifactInfo( ).getPackaging( ) != null )
                            {
                                qb.add( indexer.constructQuery( MAVEN.PACKAGING, new SourcedSearchExpression(
                                    ac.getArtifactInfo( ).getPackaging( ) ) ), BooleanClause.Occur.MUST );
                            }
                            FlatSearchRequest flatSearchRequest = new FlatSearchRequest( qb.build(), context );
                            FlatSearchResponse flatSearchResponse = indexer.searchFlat( flatSearchRequest );
                            if ( flatSearchResponse.getResults( ).isEmpty( ) )
                            {
                                log.debug( "Adding artifact '{}' to index..", ac.getArtifactInfo( ) );
                                indexerEngine.index( context, ac );
                            }
                            else
                            {
                                log.debug( "Updating artifact '{}' in index..", ac.getArtifactInfo( ) );
                                // TODO check if update exists !!
                                indexerEngine.update( context, ac );
                            }

                            context.updateTimestamp( );
                            context.commit( );


                        }
                        else
                        {
                            log.debug( "Removing artifact '{}' from index..", ac.getArtifactInfo( ) );
                            indexerEngine.remove( context, ac );
                        }
                    }
                }
                // close the context if not a repo scan request
                if ( !indexingTask.isExecuteOnEntireRepo( ) )
                {
                    log.debug( "Finishing indexing task on resource file : {}", indexingTask.getResourceFile( ) != null
                        ? indexingTask.getResourceFile( )
                        : " none " );
                    finishIndexingTask( indexingTask, repository, context );
                }
            }
            catch ( IOException e )
            {
                log.error( "Error occurred while executing indexing task '{}': {}", indexingTask, e.getMessage( ),
                    e );
                throw new TaskExecutionException( "Error occurred while executing indexing task '" + indexingTask + "'",
                    e );
            }
        }

    }

    private void finishIndexingTask( ArtifactIndexingTask indexingTask, ManagedRepository repository,
                                     IndexingContext context )
        throws TaskExecutionException
    {
        try
        {

            log.debug( "Finishing indexing" );
            context.optimize( );

            if ( repository.supportsFeature( IndexCreationFeature.class ) )
            {
                IndexCreationFeature icf = repository.getFeature( IndexCreationFeature.class );
                if ( !icf.isSkipPackedIndexCreation( ) && icf.getLocalPackedIndexPath( ) != null && icf.getLocalIndexPath().getFilePath()!=null )
                {

                    log.debug( "Creating packed index from {} on {}", context.getIndexDirectoryFile( ), icf.getLocalPackedIndexPath( ) );
                    IndexPackingRequest request = new IndexPackingRequest( context, //
                        context.acquireIndexSearcher( ).getIndexReader( ),
                        //
                        icf.getLocalPackedIndexPath( ).getFilePath().toFile( ) );

                    indexPacker.packIndex( request );
                    context.updateTimestamp( true );

                    log.debug( "Index file packed at '{}'.", icf.getLocalPackedIndexPath( ) );
                }
                else
                {
                    log.debug( "skip packed index creation" );
                }
            }
            else
            {
                log.debug( "skip packed index creation" );
            }
        }
        catch ( IOException e )
        {
            log.error( "Error occurred while executing indexing task '{}': {}", indexingTask, e.getMessage( ) );
            throw new TaskExecutionException( "Error occurred while executing indexing task '" + indexingTask + "'",
                e );
        }
    }

    public void setIndexPacker( IndexPacker indexPacker )
    {
        this.indexPacker = indexPacker;
    }

}