public bool TryRead(string filename, out Tag tag)
{
if (filename == null) throw new ArgumentNullException("filename");
try
{
var file = new File(filename);
LogWarnings(filename, file);
var t = new Tag();
PopulateFromTag(file, t);
PopulateFallbackValues(t);
if (file.Properties != null)
t.Duration = file.Properties.Duration;
tag = t;
return true;
}
catch (Exception e)
{
Log.Error(String.Format("Error reading M4A tag from {0}.", filename), e);
tag = null;
return false;
}
}
static void LogWarnings(string filename, File file)
{
if (!file.PossiblyCorrupt)
return;
foreach (var reason in file.CorruptionReasons)
Log.WarnFormat("{0} is possibly corrupt: {1}", filename, reason);
}
static byte[] GetImageData(File file)
{
var picture = file.Tag.Pictures.FirstOrDefault(p => p.Description.Contains("FrontCover")) ??
file.Tag.Pictures.FirstOrDefault();
if (picture == null)
return null;
return picture.Data.Data;
}
void PopulateFromTag(File file, Tag tag)
{
//if (!file.TagTypes.HasFlag(TagTypes.Id3v2))
// return;
tag.ImageData = GetImageData(file);
// ID3v2 Tags Reference: http://id3.org/id3v2.4.0-frames
tag.Artist = JoinPerformers(file.Tag.Performers);
tag.Title = file.Tag.Title;
tag.Year = ToStringOrDefault(file.Tag.Year);
tag.Genre = file.Tag.JoinedGenres;
tag.Publisher = file.Tag.Grouping;
tag.Bpm = ToStringOrDefault(file.Tag.BeatsPerMinute);
}
/// <summary>
/// Constructs and initializes a new instance of <see
/// cref="File" /> for a specified file abstraction with an
/// average read style.
/// </summary>
/// <param name="abstraction">
/// A <see cref="IFileAbstraction" /> object to use when
/// reading from and writing to the file.
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="abstraction" /> is <see langword="null"
/// />.
/// </exception>
public File (File.IFileAbstraction abstraction)
: this (abstraction, ReadStyle.Average)
{
}
/// <summary>
/// Constructs and initializes a new instance of <see
/// cref="File" /> for a specified file abstraction and
/// specified read style.
/// </summary>
/// <param name="abstraction">
/// A <see cref="IFileAbstraction" /> object to use when
/// reading from and writing to the file.
/// </param>
/// <param name="propertiesStyle">
/// A <see cref="ReadStyle" /> value specifying at what level
/// of accuracy to read the media properties, or <see
/// cref="ReadStyle.None" /> to ignore the properties.
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="abstraction" /> is <see langword="null"
/// />.
/// </exception>
public File (File.IFileAbstraction abstraction,
ReadStyle propertiesStyle)
: base (abstraction)
{
Read (propertiesStyle);
}
/// <summary>
/// Overwrites the existing box in the file after updating
/// the table for a size change.
/// </summary>
/// <param name="file">
/// A <see cref="File" /> object containing the file to which
/// the current instance belongs and wo which modifications
/// must be applied.
/// </param>
/// <param name="sizeDifference">
/// A <see cref="long" /> value containing the size
/// change that occurred in the file.
/// </param>
/// <param name="after">
/// A <see cref="long" /> value containing the position in
/// the file after which offsets will be invalidated. If an
/// offset is before this point, it won't be updated.
/// </param>
/// <exception cref="ArgumentNullException">
/// <param name="file" /> is <see langword="null" />.
/// </exception>
public void Overwrite (File file, long sizeDifference,
long after)
{
if (file == null)
throw new ArgumentNullException ("file");
file.Insert (Render (sizeDifference, after),
Header.Position, Size);
}