/*
 * 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.commons.vfs2;

import java.util.Arrays;
import java.util.Iterator;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;

Configures file systems individually with these options.
 To configure a file system, you set properties on a FileSystemOptions object. Most file systems provide a FileSystemConfigBuilder with specific options for that file system. 
 To use the options, pass them to FileSystemManager.resolveFile(String, FileSystemOptions). From there, the options apply to all files that are resolved relative to that file. 
See Also:
DefaultFileSystemConfigBuilder
FtpFileSystemConfigBuilder
FtpsFileSystemConfigBuilder
HdfsFileSystemConfigBuilder
HttpFileSystemConfigBuilder
WebdavFileSystemConfigBuilder
RamFileSystemConfigBuilder
ResourceFileSystemConfigBuilder
SftpFileSystemConfigBuilder
ZipFileSystemConfigBuilder/**
 * Configures file systems individually with these options.
 * <p>
 * To configure a file system, you set properties on a {@link FileSystemOptions} object. Most file systems provide a
 * {@link FileSystemConfigBuilder} with specific options for that file system.
 * </p>
 * <p>
 * To use the options, pass them to {@link FileSystemManager#resolveFile(String,FileSystemOptions)}. From there, the
 * options apply to all files that are resolved relative to that file.
 * </p>
 *
 * @see org.apache.commons.vfs2.impl.DefaultFileSystemConfigBuilder
 * @see org.apache.commons.vfs2.provider.ftp.FtpFileSystemConfigBuilder
 * @see org.apache.commons.vfs2.provider.ftps.FtpsFileSystemConfigBuilder
 * @see org.apache.commons.vfs2.provider.hdfs.HdfsFileSystemConfigBuilder
 * @see org.apache.commons.vfs2.provider.http.HttpFileSystemConfigBuilder
 * @see org.apache.commons.vfs2.provider.webdav.WebdavFileSystemConfigBuilder
 * @see org.apache.commons.vfs2.provider.ram.RamFileSystemConfigBuilder
 * @see org.apache.commons.vfs2.provider.res.ResourceFileSystemConfigBuilder
 * @see org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder
 * @see org.apache.commons.vfs2.provider.zip.ZipFileSystemConfigBuilder
 *
 */
public final class FileSystemOptions implements Cloneable {

    
The options /** The options */
    private final Map<FileSystemOptionKey, Object> options;

    
Creates a new instance.
/**
     * Creates a new instance.
     */
    public FileSystemOptions() {
        this(new TreeMap<FileSystemOptionKey, Object>());
    }

    protected FileSystemOptions(final Map<FileSystemOptionKey, Object> options) {
        this.options = options;
    }

    
Keys in the options Map.
/**
     * Keys in the options Map.
     */
    private static final class FileSystemOptionKey implements Comparable<FileSystemOptionKey> {
        
Constant used to create hashcode /** Constant used to create hashcode */
        private static final int HASH = 29;

        
The FileSystem class /** The FileSystem class */
        private final Class<? extends FileSystem> fileSystemClass;

        
The option name /** The option name */
        private final String name;

        // TODO: the parameter name suggests that the class should only be a
        // a FileSystem, however some of the tests pass in DefaultFileSystemConfigBuilder
        private FileSystemOptionKey(final Class<? extends FileSystem> fileSystemClass, final String name) {
            this.fileSystemClass = fileSystemClass;
            this.name = name;
        }

        @Override
        public int compareTo(final FileSystemOptionKey o) {
            final int ret = fileSystemClass.getName().compareTo(o.fileSystemClass.getName());
            if (ret != 0) {
                return ret;
            }
            return name.compareTo(o.name);
        }

        @Override
        public boolean equals(final Object o) {
            if (this == o) {
                return true;
            }
            if (o == null || getClass() != o.getClass()) {
                return false;
            }

            final FileSystemOptionKey that = (FileSystemOptionKey) o;

            if (!fileSystemClass.equals(that.fileSystemClass)) {
                return false;
            }
            if (!name.equals(that.name)) {
                return false;
            }

            return true;
        }

        @Override
        public int hashCode() {
            int result;
            result = fileSystemClass.hashCode();
            result = HASH * result + name.hashCode();
            return result;
        }

        @Override
        public String toString() {
            return fileSystemClass.getName() + "." + name;
        }
    }

    void setOption(final Class<? extends FileSystem> fileSystemClass, final String name, final Object value) {
        options.put(new FileSystemOptionKey(fileSystemClass, name), value);
    }

    Object getOption(final Class<? extends FileSystem> fileSystemClass, final String name) {
        final FileSystemOptionKey key = new FileSystemOptionKey(fileSystemClass, name);
        return options.get(key);
    }

    boolean hasOption(final Class<? extends FileSystem> fileSystemClass, final String name) {
        final FileSystemOptionKey key = new FileSystemOptionKey(fileSystemClass, name);
        return options.containsKey(key);
    }

    public int compareTo(final FileSystemOptions other) {
        if (this == other) {
            // the same instance
            return 0;
        }

        final int propsSz = options == null ? 0 : options.size();
        final int propsFkSz = other.options == null ? 0 : other.options.size();
        if (propsSz < propsFkSz) {
            return -1;
        }
        if (propsSz > propsFkSz) {
            return 1;
        }
        if (propsSz == 0) {
            // props empty
            return 0;
        }

        // ensure proper sequence of options
        final SortedMap<FileSystemOptionKey, Object> myOptions = options instanceof SortedMap
                ? (SortedMap<FileSystemOptionKey, Object>) options
                : new TreeMap<>(options);
        final SortedMap<FileSystemOptionKey, Object> theirOptions = other.options instanceof SortedMap
                ? (SortedMap<FileSystemOptionKey, Object>) other.options
                : new TreeMap<>(other.options);
        final Iterator<FileSystemOptionKey> optKeysIter = myOptions.keySet().iterator();
        final Iterator<FileSystemOptionKey> otherKeysIter = theirOptions.keySet().iterator();
        while (optKeysIter.hasNext()) {
            final int comp = optKeysIter.next().compareTo(otherKeysIter.next());
            if (comp != 0) {
                return comp;
            }
        }

        final Object[] array = new Object[propsSz];
        final int hash = Arrays.deepHashCode(myOptions.values().toArray(array));
        final int hashFk = Arrays.deepHashCode(theirOptions.values().toArray(array));
        if (hash < hashFk) {
            return -1;
        }
        if (hash > hashFk) {
            return 1;
        }

        // TODO: compare Entry by Entry ??
        return 0;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        if (options == null) {
            result = prime * result;
        } else {
            final SortedMap<FileSystemOptionKey, Object> myOptions = options instanceof SortedMap
                    ? (SortedMap<FileSystemOptionKey, Object>) options
                    : new TreeMap<>(options);
            result = prime * result + myOptions.keySet().hashCode();
            result = prime * result + Arrays.deepHashCode(myOptions.values().toArray(new Object[options.size()]));
        }
        return result;
    }

    @Override
    public boolean equals(final Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final FileSystemOptions other = (FileSystemOptions) obj;
        return compareTo(other) == 0;
    }

    
{@inheritDoc}
Since:
2.0/**
     * {@inheritDoc}
     *
     * @since 2.0
     */
    @Override
    public Object clone() {
        return new FileSystemOptions(new TreeMap<>(options));
    }

    @Override
    public String toString() {
        return options.toString();
    }
}