/// <summary>
/// Add alternate views and attachments to the existing message object.
/// Each component is separated boundary text defined in the contentType.Boundary variable.
/// Each component within a boundary has its own headers defining the payload.
/// Media types text/plain and text/html go into AlternateView objects.
/// All other media types will be treated as attachments.
/// </summary>
/// <param name="message"></param>
/// <param name="reader"></param>
/// <param name="contentType"></param>
private static void LoadBodyMultipart(ReceivedMessage message, TextReader reader, ContentType contentType)
{
/* http://www.w3.org/Protocols/rfc1341/7_2_Multipart.html */
//each component of the multipart message will be separated by a boundary.
//each section of text within a boundary should have headers to describe it or in the absence of headers
//assumed to be ASCII text/plain.
//a valid message component is preceded and followed by a the boundary text
//which is two hyphens followed by the value Boundary property of the main ContentType object.
//UNDONE: Unsupported for now: In the case of multipart/related, the attachments should be done as LinkedResources of the text/html AlternativeView.
//This is a nice to have but not critical. Last time I checked, Gmail didn't even support these kinds
//of internal references, either.
/*******************************************************************************************
* the text following the message headers and preceding the first boundary is to be ignored.
* any text at after the final boundary is also to be ignored.
* /*******************************************************************************************/
foreach (var part in LoadMultipart(reader, contentType))
{
if (part is AlternateView)
{
message.AlternateViews.Add(part as AlternateView);
}
else if (part is Attachment)
{
message.Attachments.Add(part as Attachment);
}
}
//scroll past epilogue
string buff;
while (null != (buff = reader.ReadLine()) && (LineType.EOF != GetLineType(buff, contentType)))
{
;
}
}
/// <summary>
/// Parse a TextReader. The calling code is responsible for closing the reader and the stream.
/// </summary>
/// <param name="reader"></param>
/// <returns>Returns a ReceivedMessage object loaded from the TextReader. Return null if the TextReader is null.</returns>
public ReceivedMessage Parse( TextReader reader )
{
if( reader == null )
return null;
ReceivedMessage message = new ReceivedMessage();
if( !LoadHeaders( reader, message.ReceivedHeaders, message.RawReceivedHeaders ) )
throw new InvalidDataException( "MIME Stream must contain headers." );
LoadMailAddresses( message );
Debug.WriteLine( message.ReceivedHeaders["subject"] );
message.Subject = message.ReceivedHeaders["subject"];
//Load message body and attachments
/*
* http://tools.ietf.org/html/rfc2046
* http://en.wikipedia.org/wiki/MIME#Content-Type
*
* fully supported simple messages:
* text/plain, text/html (text/html is not compliant, should be multipart/alternative)
* text/(unrecognized subtype) treated as application/octet-stream
*
* supported multipart messages:
* multipart/mixed, multipart/alternative
* multipart/digest
*
* partially supported
* multipart/related => treat as multipart/mixed. related parts are not linked.
* multipart/signed -> treat as multipart/mixed
* multipart/encrypted -> treat as multipart/mixed
* mutipart/form-data -> treat as multipart/mixed
* multipart/report -> treat as multipart/mixed
* multipart/appledouble (RFC 1740) -> resource fork is discarded and the data fork becomes an attachment.
*/
//Load text/plain and text/html as a simple body text. Otherwise, treat the message as multipart.
//Anything that is text/plain or text/html should become an alternative view. Everything else becomes an attachment.
ContentType contentType = GetContentType( message.ReceivedHeaders );
if( 0 == string.Compare( contentType.MediaType, MediaTypeNames.Text.Plain, true ) ||
0 == string.Compare( contentType.MediaType, MediaTypeNames.Text.Html, true ) )
{
LoadBodyText( message, reader, contentType );
}
else
{
LoadBodyMultipart( message, reader, contentType );
}
return message;
}
/// <summary>
/// Loads From, To, CC and Bcc properties using the values stored in the headers.
/// </summary>
/// <param name="message"></param>
private static void LoadMailAddresses( ReceivedMessage message )
{
try
{
if( !string.IsNullOrEmpty( message.ReceivedHeaders["from"] ) )
message.From = new MailAddress( message.ReceivedHeaders["from"] );
if( !string.IsNullOrEmpty( message.ReceivedHeaders["reply-to"] ) )
#if NET_FX4
message.ReplyToList.Add(new MailAddress(message.ReceivedHeaders["reply-to"]));
#else
message.ReplyTo = new MailAddress( message.ReceivedHeaders["reply-to"] );
#endif
}
catch( Exception ex )
{
//swallow exception thrown by bad data.
if( !(ex is FormatException) )
throw ex;
}
LoadMailAddresses( message.To, message.ReceivedHeaders["to"] );
LoadMailAddresses( message.CC, message.ReceivedHeaders["cc"] );
LoadMailAddresses( message.Bcc, message.ReceivedHeaders["bcc"] );
}
private static void LoadBodyText( ReceivedMessage message, TextReader reader, ContentType contentType )
{
LineType lastLineType; //not used, because the message is not multipart
message.Body = LoadBodyString( reader, message.ReceivedHeaders, contentType, out lastLineType );
message.IsBodyHtml = (contentType.MediaType == MediaTypeNames.Text.Html);
}
/// <summary>
/// Add alternate views and attachments to the existing message object.
/// Each component is separated boundary text defined in the contentType.Boundary variable.
/// Each component within a boundary has its own headers defining the payload.
/// Media types text/plain and text/html go into AlternateView objects.
/// All other media types will be treated as attachments.
/// </summary>
/// <param name="message"></param>
/// <param name="reader"></param>
/// <param name="contentType"></param>
private static void LoadBodyMultipart( ReceivedMessage message, TextReader reader, ContentType contentType )
{
/* http://www.w3.org/Protocols/rfc1341/7_2_Multipart.html */
//each component of the multipart message will be separated by a boundary.
//each section of text within a boundary should have headers to describe it or in the absence of headers
//assumed to be ASCII text/plain.
//a valid message component is preceded and followed by a the boundary text
//which is two hyphens followed by the value Boundary property of the main ContentType object.
//UNDONE: Unsupported for now: In the case of multipart/related, the attachments should be done as LinkedResources of the text/html AlternativeView.
//This is a nice to have but not critical. Last time I checked, Gmail didn't even support these kinds
//of internal references, either.
/*******************************************************************************************
* the text following the message headers and preceding the first boundary is to be ignored.
* any text at after the final boundary is also to be ignored.
/*******************************************************************************************/
foreach( var part in LoadMultipart( reader, contentType ) )
{
if( part is AlternateView )
message.AlternateViews.Add( part as AlternateView );
else if( part is Attachment )
message.Attachments.Add( part as Attachment );
}
//scroll past epilogue
string buff;
while( null != (buff = reader.ReadLine()) && (LineType.EOF != GetLineType( buff, contentType )) );
}