/*
 * 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.ignite.internal.processors.cache.persistence.wal.io;

import java.io.IOException;
import org.apache.ignite.internal.processors.cache.persistence.file.FileIO;
import org.apache.ignite.internal.processors.cache.persistence.file.FileIOFactory;
import org.apache.ignite.internal.processors.cache.persistence.wal.ByteBufferExpander;
import org.apache.ignite.internal.processors.cache.persistence.wal.FileDescriptor;
import org.apache.ignite.internal.processors.cache.persistence.wal.aware.SegmentAware;
import org.apache.ignite.internal.processors.cache.persistence.wal.SegmentRouter;

/**
 * Implementation of factory to provide I/O interfaces for read primitives with files.
 *
 * Creating {@link FileInput} with ability locked segment during reading.
 */
public class LockedSegmentFileInputFactory implements SegmentFileInputFactory {
    /** Holder of actual information of latest manipulation on WAL segments. */
    private final SegmentAware segmentAware;
    /** Manager of segment location. */
    private final SegmentRouter segmentRouter;
    /** {@link FileIO} factory definition.*/
    private final FileIOFactory fileIOFactory;

    /**
     * @param segmentAware Holder of actual information of latest manipulation on WAL segments.
     * @param segmentRouter Manager of segment location.
     * @param fileIOFactory {@link FileIO} factory definition.
     */
    public LockedSegmentFileInputFactory(
        SegmentAware segmentAware,
        SegmentRouter segmentRouter,
        FileIOFactory fileIOFactory) {
        this.segmentAware = segmentAware;
        this.segmentRouter = segmentRouter;
        this.fileIOFactory = fileIOFactory;
    }

    /** {@inheritDoc} */
    @Override public FileInput createFileInput(SegmentIO segmentIO, ByteBufferExpander buf) throws IOException {
        return new LockedReadFileInput(
            buf,
            segmentIO,
            segmentAware,
            id -> {
                FileDescriptor segment = segmentRouter.findSegment(id);

                return segment.toIO(fileIOFactory);
            }
        );
    }
}