/// <summary>
/// Parses set of <see cref="StringSegment"/> supplying the individual lines of a <c>multipart</c> body, returning contituent parts.
/// </summary>
/// <param name="bodyLines">The <c>multipart</c> body lines</param>
/// <param name="boundary">The <c>multipart</c> boundary string</param>
/// <returns>The constituent body parts.</returns>
public static IEnumerable <MimePart> ReadBodyParts(IEnumerable <StringSegment> bodyLines, string boundary)
{
if (bodyLines == null)
{
throw new ArgumentNullException("bodyLines");
}
if (string.IsNullOrEmpty(boundary))
{
throw new MimeException(MimeError.MissingBoundarySeparator);
}
IEnumerator <StringSegment> lineEnumerator = bodyLines.GetEnumerator();
StringSegment part = StringSegment.Null;
StringSegment prevLine = StringSegment.Null;
MimePartType expectedPart = MimePartType.BodyPrologue;
//
// As per the Multipart Spec:
// The boundary delimiter is actually CRLF--boundary
// So we must maintain a stack (prevLine)..
//
while (expectedPart != MimePartType.BodyEpilogue && lineEnumerator.MoveNext())
{
StringSegment line = lineEnumerator.Current;
if (IsBoundary(line, boundary))
{
if (!part.IsNull)
{
part.Union(prevLine);
}
//
// When we hit a boundary, we yield the part we've collected so far
//
MimePartType partType = expectedPart;
switch (expectedPart)
{
default:
throw new MimeException(MimeError.InvalidBodySubpart);
case MimePartType.BodyPrologue:
expectedPart = MimePartType.BodyPart;
break;
case MimePartType.BodyPart:
if (IsBoundaryEnd(line))
{
expectedPart = MimePartType.BodyEpilogue;
}
break;
}
if (!part.IsNull)
{
yield return(new MimePart(partType, part));
}
prevLine = StringSegment.Null;
part = StringSegment.Null;
}
else
{
if (!prevLine.IsNull)
{
part.Union(prevLine);
}
prevLine = line;
}
}
if (expectedPart != MimePartType.BodyEpilogue)
{
throw new MimeException(MimeError.InvalidBodySubpart);
}
// Epilogue
part = StringSegment.Null;
while (lineEnumerator.MoveNext())
{
part.Union(lineEnumerator.Current);
}
if (!part.IsEmpty)
{
yield return(new MimePart(MimePartType.BodyEpilogue, part));
}
}
/// <summary>
/// Expands the source segment for this entity
/// </summary>
internal virtual void AppendSourceText(StringSegment segment)
{
m_sourceText.Union(segment);
}