/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
 * or http://forgerock.org/license/CDDLv1.0.html.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at legal-notices/CDDLv1_0.txt.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information:
 *      Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 *
 *
 *      Copyright 2010 Sun Microsystems, Inc.
 *      Portions copyright 2012 ForgeRock AS.
 */

package org.forgerock.opendj.ldap;

import java.util.LinkedHashMap;

import org.forgerock.i18n.LocalizedIllegalArgumentException;
import org.forgerock.opendj.ldap.requests.Requests;

import org.forgerock.util.Reject;

/**
 * An implementation of the {@code Entry} interface which uses a
 * {@code LinkedHashMap} for storing attributes. Attributes are returned in the
 * same order that they were added to the entry. All operations are supported by
 * this implementation. For example, you can build an entry like this:
 *
 * <pre>
 * Entry entry = new LinkedHashMapEntry("cn=Bob,ou=People,dc=example,dc=com")
 *    .addAttribute("cn", "Bob")
 *    .addAttribute("objectclass", "top")
 *    .addAttribute("objectclass", "person")
 *    .addAttribute("objectclass", "organizationalPerson")
 *    .addAttribute("objectclass", "inetOrgPerson")
 *    .addAttribute("mail", "subgenius@example.com")
 *    .addAttribute("sn", "Dobbs");
 * </pre>
 *
 * A {@code LinkedHashMapEntry} stores references to attributes which have been
 * added using the {@link #addAttribute} methods. Attributes sharing the same
 * attribute description are merged by adding the values of the new attribute to
 * the existing attribute. More specifically, the existing attribute must be
 * modifiable for the merge to succeed. Similarly, the {@link #removeAttribute}
 * methods remove the specified values from the existing attribute. The
 * {@link #replaceAttribute} methods remove the existing attribute (if present)
 * and store a reference to the new attribute - neither the new or existing
 * attribute need to be modifiable in this case.
 */
public final class LinkedHashMapEntry extends AbstractMapEntry {
    /**
     * An entry factory which can be used to create new linked hash map entries.
     */
    public static final EntryFactory FACTORY = new EntryFactory() {
        public Entry newEntry(final DN name) {
            return new LinkedHashMapEntry(name);
        }
    };

    /**
     * Creates an entry having the same distinguished name, attributes, and
     * object classes of the provided entry. This constructor performs a deep
     * copy of {@code entry} and will copy each attribute as a
     * {@link LinkedAttribute}.
     * <p>
     * A shallow copy constructor is provided by
     * {@link #LinkedHashMapEntry(Entry)}.
     *
     * @param entry
     *            The entry to be copied.
     * @return A deep copy of {@code entry}.
     * @throws NullPointerException
     *             If {@code entry} was {@code null}.
     * @see #LinkedHashMapEntry(Entry)
     */
    public static LinkedHashMapEntry deepCopyOfEntry(final Entry entry) {
        LinkedHashMapEntry copy = new LinkedHashMapEntry(entry.getName());
        for (final Attribute attribute : entry.getAllAttributes()) {
            copy.addAttribute(new LinkedAttribute(attribute));
        }
        return copy;
    }

    /**
     * Creates an entry with an empty (root) distinguished name and no
     * attributes.
     */
    public LinkedHashMapEntry() {
        this(DN.rootDN());
    }

    /**
     * Creates an empty entry using the provided distinguished name and no
     * attributes.
     *
     * @param name
     *            The distinguished name of this entry.
     * @throws NullPointerException
     *             If {@code name} was {@code null}.
     */
    public LinkedHashMapEntry(final DN name) {
        super(Reject.checkNotNull(name), new LinkedHashMap<AttributeDescription, Attribute>());
    }

    /**
     * Creates an entry having the same distinguished name, attributes, and
     * object classes of the provided entry. This constructor performs a shallow
     * copy of {@code entry} and will not copy the attributes contained in
     * {@code entry}.
     * <p>
     * A deep copy constructor is provided by {@link #deepCopyOfEntry(Entry)}
     *
     * @param entry
     *            The entry to be copied.
     * @throws NullPointerException
     *             If {@code entry} was {@code null}.
     * @see #deepCopyOfEntry(Entry)
     */
    public LinkedHashMapEntry(final Entry entry) {
        this(entry.getName());
        for (final Attribute attribute : entry.getAllAttributes()) {
            addAttribute(attribute);
        }
    }

    /**
     * Creates an empty entry using the provided distinguished name decoded
     * using the default schema.
     *
     * @param name
     *            The distinguished name of this entry.
     * @throws LocalizedIllegalArgumentException
     *             If {@code name} could not be decoded using the default
     *             schema.
     * @throws NullPointerException
     *             If {@code name} was {@code null}.
     */
    public LinkedHashMapEntry(final String name) {
        this(DN.valueOf(name));
    }

    /**
     * Creates a new entry using the provided lines of LDIF decoded using the
     * default schema.
     *
     * @param ldifLines
     *            Lines of LDIF containing the an LDIF add change record or an
     *            LDIF entry record.
     * @throws LocalizedIllegalArgumentException
     *             If {@code ldifLines} was empty, or contained invalid LDIF, or
     *             could not be decoded using the default schema.
     * @throws NullPointerException
     *             If {@code ldifLines} was {@code null} .
     */
    public LinkedHashMapEntry(final String... ldifLines) {
        this(Requests.newAddRequest(ldifLines));
    }

}
