package org.eclipse.aether.transport.file;

/*
 * 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.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;

import org.eclipse.aether.repository.RemoteRepository;
import org.eclipse.aether.spi.connector.transport.AbstractTransporter;
import org.eclipse.aether.spi.connector.transport.GetTask;
import org.eclipse.aether.spi.connector.transport.PeekTask;
import org.eclipse.aether.spi.connector.transport.PutTask;
import org.eclipse.aether.spi.connector.transport.TransportTask;
import org.eclipse.aether.transfer.NoTransporterException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * A transporter using {@link java.io.File}.
 */
final class FileTransporter
    extends AbstractTransporter
{

    private static final Logger LOGGER = LoggerFactory.getLogger( FileTransporter.class );

    private final File basedir;

    FileTransporter( RemoteRepository repository )
        throws NoTransporterException
    {
        if ( !"file".equalsIgnoreCase( repository.getProtocol() ) )
        {
            throw new NoTransporterException( repository );
        }
        basedir = new File( PathUtils.basedir( repository.getUrl() ) ).getAbsoluteFile();
    }

    File getBasedir()
    {
        return basedir;
    }

    public int classify( Throwable error )
    {
        if ( error instanceof ResourceNotFoundException )
        {
            return ERROR_NOT_FOUND;
        }
        return ERROR_OTHER;
    }

    @Override
    protected void implPeek( PeekTask task )
        throws Exception
    {
        getFile( task, true );
    }

    @Override
    protected void implGet( GetTask task )
        throws Exception
    {
        File file = getFile( task, true );
        utilGet( task, new FileInputStream( file ), true, file.length(), false );
    }

    @Override
    protected void implPut( PutTask task )
        throws Exception
    {
        File file = getFile( task, false );
        file.getParentFile().mkdirs();
        try
        {
            utilPut( task, new FileOutputStream( file ), true );
        }
        catch ( Exception e )
        {
            if ( !file.delete() && file.exists() )
            {
                LOGGER.debug( "Could not delete partial file {}", file );
            }
            throw e;
        }
    }

    private File getFile( TransportTask task, boolean required )
        throws Exception
    {
        String path = task.getLocation().getPath();
        if ( path.contains( "../" ) )
        {
            throw new IllegalArgumentException( "illegal resource path: " + path );
        }
        File file = new File( basedir, path );
        if ( required && !file.exists() )
        {
            throw new ResourceNotFoundException( "Could not locate " + file );
        }
        return file;
    }

    @Override
    protected void implClose()
    {
    }

}