PaddingObject.cs

//
// PaddingObject.cs: Provides a representation of an ASF Padding object which
// can be read from and written to disk.
//
// Author:
//   Brian Nickel (brian.nickel@gmail.com)
//
// Copyright (C) 2006-2007 Brian Nickel
// 
// This library is free software; you can redistribute it and/or modify
// it  under the terms of the GNU Lesser General Public License version
// 2.1 as published by the Free Software Foundation.
//
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
// USA
//

using System;

namespace TagLib.Asf {
      /// <summary>
      ///    This class extends <see cref="Object" /> to provide a
      ///    representation of an ASF Padding object which can be read from
      ///    and written to disk.
      /// </summary>
00033       public class PaddingObject : Object
      {
            #region Private Fields
            
            /// <summary>
            ///    Contains the size of the current instance.
            /// </summary>
00040             private ulong size;
            
            #endregion
            
            
            
            #region Constructors
            
            /// <summary>
            ///    Constructs and initializes a new instance of <see
            ///    cref="PaddingObject" /> by reading the contents from a
            ///    specified position in a specified file.
            /// </summary>
            /// <param name="file">
            ///    A <see cref="Asf.File" /> object containing the file from
            ///    which the contents of the new instance are to be read.
            /// </param>
            /// <param name="position">
            ///    A <see cref="long" /> value specify at what position to
            ///    read the object.
            /// </param>
            /// <exception cref="ArgumentNullException">
            ///    <paramref name="file" /> is <see langword="null" />.
            /// </exception>
            /// <exception cref="ArgumentOutOfRangeException">
            ///    <paramref name="position" /> is less than zero or greater
            ///    than the size of the file.
            /// </exception>
            /// <exception cref="CorruptFileException">
            ///    The object read from disk does not have the correct GUID
            ///    or smaller than the minimum size.
            /// </exception>
00072             public PaddingObject (Asf.File file, long position)
                  : base (file, position)
            {
                  if (!Guid.Equals (Asf.Guid.AsfPaddingObject))
                        throw new CorruptFileException (
                              "Object GUID incorrect.");
                  
                  if (OriginalSize < 24)
                        throw new CorruptFileException (
                              "Object size too small.");
                  
                  size = OriginalSize;
            }
            
            /// <summary>
            ///    Constructs and initializes a new instance of <see
            ///    cref="PaddingObject" /> of a specified size.
            /// </summary>
            /// <param name="size">
            ///    A <see cref="uint" /> value specifying the number of
            ///    bytes the new instance is to take up on disk.
            /// </param>
00094             public PaddingObject (uint size)
                  : base (Asf.Guid.AsfPaddingObject)
            {
                  this.size = size;
            }
            
            #endregion
            
            
            
            #region Prublic Properties
            
            /// <summary>
            ///    Gets and sets the number of bytes the current instance
            ///    will take up on disk.
            /// </summary>
            /// <value>
            ///    A <see cref="ulong" /> value containing the size of the
            ///    current instance on disk.
            /// </value>
00114             public ulong Size {
                  get {return size;}
                  set {size = value;}
            }
            
            #endregion
            
            
            
            #region Public Methods
            
            /// <summary>
            ///    Renders the current instance as a raw ASF object.
            /// </summary>
            /// <returns>
            ///    A <see cref="ByteVector" /> object containing the
            ///    rendered version of the current instance.
            /// </returns>
00132             public override ByteVector Render ()
            {
                  return Render (new ByteVector ((int) (size - 24)));
            }
            
            #endregion
      }
}