/// <summary>
/// Reads a tag starting at a specified position and moves the
/// cursor to its start position.
/// </summary>
/// <param name="start">
/// A <see cref="long" /> value reference specifying at what
/// position the potential tag starts. If a tag is found,
/// this value will be updated to the position at which the
/// found tag ends.
/// </param>
/// <returns>
/// A <see cref="TagLibSharp.Tag" /> object representing the tag
/// found at the specified position, or <see langword="null"
/// /> if no tag was found.
/// </returns>
private TagLibSharp.Tag ReadTag(ref long start)
{
long end = start;
TagTypes type = ReadTagInfo(ref end);
TagLibSharp.Tag tag = null;
try {
switch (type)
{
case TagTypes.Ape:
tag = new Ape.Tag(file, start);
break;
case TagTypes.Id3v2:
tag = new Id3v2.Tag(file, start);
break;
}
} catch (CorruptFileException e) {
Console.Error.WriteLine("taglib-sharp caught exception creating tag: {0}", e);
}
start = end;
return(tag);
}
/// <summary>
/// Adds a tag of a specified type to the current instance,
/// optionally copying values from an existing type.
/// </summary>
/// <param name="type">
/// A <see cref="TagTypes" /> value specifying the type of
/// tag to add to the current instance. At the time of this
/// writing, this is limited to <see cref="TagTypes.Ape" />
/// and <see cref="TagTypes.Id3v2" />.
/// </param>
/// <param name="copy">
/// A <see cref="TagLibSharp.Tag" /> to copy values from using
/// <see cref="TagLibSharp.Tag.CopyTo" />, or <see
/// langword="null" /> if no tag is to be copied.
/// </param>
/// <returns>
/// The <see cref="TagLibSharp.Tag" /> object added to the current
/// instance, or <see langword="null" /> if it couldn't be
/// created.
/// </returns>
/// <remarks>
/// ID3v2 tags are added at the end of the current instance,
/// while other tags are added to the beginning.
/// </remarks>
public TagLibSharp.Tag AddTag(TagTypes type, TagLibSharp.Tag copy)
{
TagLibSharp.Tag tag = null;
if (type == TagTypes.Id3v2)
{
tag = new Id3v2.Tag();
}
else if (type == TagTypes.Ape)
{
tag = new Ape.Tag();
(tag as Ape.Tag).HeaderPresent = true;
}
if (tag != null)
{
if (copy != null)
{
copy.CopyTo(tag, true);
}
AddTag(tag);
}
return(tag);
}
/// <summary>
/// Reads a tag ending at a specified position and moves the
/// cursor to its start position.
/// </summary>
/// <param name="end">
/// A <see cref="long" /> value reference specifying at what
/// position the potential tag ends at. If a tag is found,
/// this value will be updated to the position at which the
/// found tag starts.
/// </param>
/// <returns>
/// A <see cref="TagLibSharp.Tag" /> object representing the tag
/// found at the specified position, or <see langword="null"
/// /> if no tag was found.
/// </returns>
private TagLibSharp.Tag ReadTag(ref long end)
{
long start = end;
TagTypes type = ReadTagInfo(ref start);
TagLibSharp.Tag tag = null;
try {
switch (type)
{
case TagTypes.Ape:
tag = new Ape.Tag(file, end - Footer.Size);
break;
case TagTypes.Id3v2:
tag = new Id3v2.Tag(file, start);
break;
case TagTypes.Id3v1:
tag = new Id3v1.Tag(file, start);
break;
}
end = start;
} catch (CorruptFileException) {
}
return(tag);
}
/// <summary>
/// Gets a tag of a specified type from the current instance,
/// optionally creating a new tag if possible.
/// </summary>
/// <param name="type">
/// A <see cref="TagTypes" /> value indicating the
/// type of tag to read.
/// </param>
/// <param name="create">
/// A <see cref="bool" /> value specifying whether or not to
/// try and create the tag if one is not found.
/// </param>
/// <returns>
/// A <see cref="Tag" /> object containing the tag that was
/// found in or added to the current instance. If no
/// matching tag was found and none was created, <see
/// langword="null" /> is returned.
/// </returns>
/// <remarks>
/// If a <see cref="Id3v2.Tag" /> is added to the
/// current instance, it will be placed at the start of the
/// file. On the other hand, <see cref="Id3v1.Tag" />
/// <see cref="Tag" /> will be added to the end of
/// the file. All other tag types will be ignored.
/// </remarks>
public override TagLibSharp.Tag GetTag(TagTypes type, bool create)
{
TagLibSharp.Tag t = (Tag as NonContainer.Tag)
.GetTag(type);
if (t != null || !create)
{
return(t);
}
switch (type)
{
case TagTypes.Id3v1:
return(EndTag.AddTag(type, Tag));
case TagTypes.Id3v2:
return(StartTag.AddTag(type, Tag));
case TagTypes.Ape:
return(EndTag.AddTag(type, Tag));
default:
return(null);
}
}
/// <summary>
/// Adds a tag of a specified type to the current instance,
/// optionally copying values from an existing type.
/// </summary>
/// <param name="type">
/// A <see cref="TagTypes" /> value specifying the type of
/// tag to add to the current instance. At the time of this
/// writing, this is limited to <see cref="TagTypes.Ape" />,
/// <see cref="TagTypes.Id3v1" />, and <see
/// cref="TagTypes.Id3v2" />.
/// </param>
/// <param name="copy">
/// A <see cref="TagLibSharp.Tag" /> to copy values from using
/// <see cref="TagLibSharp.Tag.CopyTo" />, or <see
/// langword="null" /> if no tag is to be copied.
/// </param>
/// <returns>
/// The <see cref="TagLibSharp.Tag" /> object added to the current
/// instance, or <see langword="null" /> if it couldn't be
/// created.
/// </returns>
/// <remarks>
/// ID3v2 tags are added at the end of the current instance,
/// while other tags are added to the beginning.
/// </remarks>
public TagLibSharp.Tag AddTag(TagTypes type, TagLibSharp.Tag copy)
{
TagLibSharp.Tag tag = null;
if (type == TagTypes.Id3v1)
{
tag = new Id3v1.Tag();
}
else if (type == TagTypes.Id3v2)
{
Id3v2.Tag tag32 = new Id3v2.Tag();
tag32.Version = 4;
tag32.Flags |= Id3v2.HeaderFlags.FooterPresent;
tag = tag32;
}
else if (type == TagTypes.Ape)
{
tag = new Ape.Tag();
}
if (tag != null)
{
if (copy != null)
{
copy.CopyTo(tag, true);
}
if (type == TagTypes.Id3v1)
{
AddTag(tag);
}
else
{
InsertTag(0, tag);
}
}
return(tag);
}
