driver733/VK-Uploader

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2018 Mikhail Yakushin
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package com.driver733.vkuploader.media;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;

/**
 * Returns a random file from a directory.
 *
 * @since 0.3
 */
public final class RandomMediaFromDirectory implements Media, MediaSingle {

    /**
     * Path to directory with files.
     */
    private final Path directory;

    /**
     * Ctor.
     * @param directory Path to dir with files.
     */
    public RandomMediaFromDirectory(final Path directory) {
        this.directory = directory;
    }

    @Override
    public List<Path> files() throws IOException {
        return Files.list(
            this.directory
        ).filter(
            file -> Files.isRegularFile(file)
        ).collect(
            Collectors.collectingAndThen(
                Collectors.toList(),
                list -> {
                    Collections.shuffle(list);
                    return list;
                }
            )
        );
    }

    @Override
    public Path file() throws IOException {
        return this.files().get(0);
    }
}