using System;
namespace Unosquare.Swan.Networking.Ldap {
  /// <summary>
  /// A single add, delete, or replace operation to an LdapAttribute.
  /// An LdapModification contains information on the type of modification
  /// being performed, the name of the attribute to be replaced, and the new
  /// value.  Multiple modifications are expressed as an array of modifications,
  /// i.e., <c>LdapModification[]</c>.
  /// An LdapModification or an LdapModification array enable you to modify
  /// an attribute of an Ldap entry. The entire array of modifications must
  /// be performed by the server as a single atomic operation in the order they
  /// are listed. No changes are made to the directory unless all the operations
  /// succeed. If all succeed, a success result is returned to the application.
  /// It should be noted that if the connection fails during a modification,
  /// it is indeterminate whether the modification occurred or not.
  /// There are three types of modification operations: Add, Delete,
  /// and Replace.
  /// <b>Add: </b>Creates the attribute if it doesn't exist, and adds
  /// the specified values. This operation must contain at least one value, and
  /// all values of the attribute must be unique.
  /// <b>Delete: </b>Deletes specified values from the attribute. If no
  /// values are specified, or if all existing values of the attribute are
  /// specified, the attribute is removed. Mandatory attributes cannot be
  /// removed.
  /// <b>Replace: </b>Creates the attribute if necessary, and replaces
  /// all existing values of the attribute with the specified values.
  /// If you wish to keep any existing values of a multi-valued attribute,
  /// you must include these values in the replace operation.
  /// A replace operation with no value will remove the entire attribute if it
  /// exists, and is ignored if the attribute does not exist.
  /// Additional information on Ldap modifications is available in section 4.6
  /// of. <a href="http://www.ietf.org/rfc/rfc2251.txt">rfc2251.txt</a>
  /// </summary>
  /// <seealso cref="LdapConnection.Modify"></seealso>
  /// <seealso cref="LdapAttribute"></seealso>
  public sealed class LdapModification : LdapMessage {
    /// <summary>
    /// Initializes a new instance of the <see cref="LdapModification" /> class.
    /// Specifies a modification to be made to an attribute.
    /// </summary>
    /// <param name="op">The op.</param>
    /// <param name="attr">The attribute to modify.</param>
    public LdapModification(LdapModificationOp op, LdapAttribute attr) {
      this.Op = op;
      this.Attribute = attr;
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="LdapModification"/> class.
    /// </summary>
    /// <param name="op">The op.</param>
    /// <param name="attrName">Name of the attribute.</param>
    /// <param name="attrValue">The attribute value.</param>
    public LdapModification(LdapModificationOp op, String attrName, String attrValue)
        : this(op, new LdapAttribute(attrName, attrValue)) {
      // placeholder
    }

    /// <summary>
    /// Returns the attribute to modify, with any existing values.
    /// </summary>
    /// <value>
    /// The attribute.
    /// </value>
    public LdapAttribute Attribute {
      get;
    }

    /// <summary>
    /// Returns the type of modification specified by this object.
    /// </summary>
    /// <value>
    /// The op.
    /// </value>
    public LdapModificationOp Op {
      get;
    }
  }
}