private void ProcessMutipartBody()
{
/**
* extract boundary from content-type
*/
string boundary = string.Empty;
int boundaryBegin = _content_type.ToLower().IndexOf("boundary=");
if (boundaryBegin > 0)
{
boundaryBegin += 9;
int boundaryEnd = _content_type.IndexOfAny(_boundaryDelimiters, boundaryBegin);
if (boundaryEnd < 0)
{
boundaryEnd = _content_type.Length;
}
if (boundaryEnd > boundaryBegin)
{
boundary = _content_type.Substring(
boundaryBegin, boundaryEnd - boundaryBegin).Replace("\"", string.Empty).Trim();
}
}
if (boundary.Length == 0)
{
_bodyBuilder.Append("Bad multipart message: the \"Content-Type\" header doesn't contain valid boundary. Message source follows as plain text.\r\n\r\n");
_bodyBuilder.Append(_body);
return;
}
boundary = "--" + boundary;
string finishingBoundary = boundary + "--";
string[] lines = _body.Split('\n');
string line = string.Empty;
int i = 0;
bool inHeaders = true;
bool isHtmlBody = false;
bool isAttachment = false;
bool isInline = false;
bool isAlternative = false;
MessagePartEncoding MIME_encoding = MessagePartEncoding.None;
string bodyCharset = string.Empty;
string filename = string.Empty;
string altBoundary = string.Empty;
string contentId = string.Empty;
_partBuilder.Length = 0;
/**
* search for the first boundary
*/
for ( ; i < lines.Length; ++i)
{
line = lines[i].TrimEnd('\r');
if (line.StartsWith(boundary))
{
++i;
break;
}
}
for ( ; i < lines.Length && !line.StartsWith(finishingBoundary); ++i)
{
line = lines[i].TrimEnd('\r');
/**
* if not in headers then process next part
*/
if (!inHeaders)
{
/**
* if filename not present process body
*/
if (filename.Length == 0)
{
if (isHtmlBody)
{
i = ProcessHTMLBody(lines, i, boundary, MIME_encoding, bodyCharset);
}
else
{
i = ProcessBody(lines, i, boundary, MIME_encoding, bodyCharset);
/**
* if body is nested multipart/alternative then parse it in its turn
*/
if (isAlternative && altBoundary.Length > 0)
{
MultiPartBodyParser parser = new MultiPartBodyParser(
_bodyBuilder.ToString(), "multipart/alternative; boundary=" +
altBoundary, _content_transfer_encoding, _charset);
_bodyBuilder.Length = 0;
_htmlBodyBuilder.Length = 0;
_parts.AddRange(parser.GetParts());
}
}
}
else
/**
* if filename present then we are to extract attacment
*/
{
i = ProcessAttachment(lines, i, boundary, MIME_encoding);
if (MIMEParser.IsMIMEString(filename))
{
filename = MIMEParser.DecodeMIMEString(filename);
}
string partStr = _partBuilder.ToString();
MessagePart attachment = null;
switch (MIME_encoding)
{
case MessagePartEncoding.QuotedPrintable:
{
attachment = new MessagePart(MIMEParser.DecodeQuotedPrintable(partStr), filename);
break;
}
case MessagePartEncoding.Base64:
{
byte[] bytes = MIMEParser.DecodeBase64(partStr);
if (bytes != null)
{
attachment = new MessagePart(bytes, filename);
}
break;
}
default:
{
attachment = new MessagePart(
MIMEParser.GetEncodingExceptionSafe(bodyCharset).GetBytes(partStr), filename);
break;
}
}
if (attachment != null)
{
if (isInline)
{
attachment.PartType = MessagePartTypes.Inline;
}
else
{
if (contentId.Length > 0)
{
attachment.PartType = MessagePartTypes.Embedded;
attachment.ContentId = contentId;
}
}
_parts.Add(attachment);
}
_partBuilder.Length = 0;
}
/**
* reset encoding, charset, filename, alternative boundary, content-id and flags
*/
MIME_encoding = MessagePartEncoding.None;
bodyCharset = _charset;
filename = altBoundary = contentId = string.Empty;
inHeaders = true;
isHtmlBody = isAttachment = isInline = false;
}
else
{
if (line.Length == 0)
{
inHeaders = false;
}
else
{
string lowerLine = line.ToLower();
if (lowerLine.StartsWith("content-type:"))
{
string content_type = lowerLine.Substring(14);
if (content_type.StartsWith("multipart/alternative") ||
content_type.StartsWith("multipart/related"))
{
isAlternative = true;
}
else if (content_type.StartsWith("application/") || content_type.StartsWith("image/"))
{
isAttachment = true;
}
else
{
if (content_type.StartsWith("text/html"))
{
isHtmlBody = true;
}
bodyCharset = DetectCharset(lowerLine, line, _charset);
}
}
else if (lowerLine.StartsWith("content-transfer-encoding:"))
{
string encoding = lowerLine.Substring(27);
if (encoding.StartsWith("quoted-printable"))
{
MIME_encoding = MessagePartEncoding.QuotedPrintable;
}
else if (encoding.StartsWith("base64"))
{
MIME_encoding = MessagePartEncoding.Base64;
}
}
else if (lowerLine.StartsWith("content-disposition:"))
{
string headerValue = lowerLine.Substring(21);
if (headerValue.StartsWith("attachment"))
{
isAttachment = true;
}
else if (headerValue.StartsWith("inline"))
{
isInline = true;
}
}
else if (lowerLine.StartsWith("content-id:"))
{
contentId = line.Substring(12).Replace("<", "").Replace(">", "");
}
if ((isAttachment || isInline) && filename.Length == 0)
{
int nameBegin;
if ((nameBegin = lowerLine.IndexOf("filename=")) > 0)
{
filename = line.Substring(nameBegin + 9).Replace("\"", string.Empty).Trim();
}
if ((nameBegin = lowerLine.IndexOf("name=")) > 0)
{
filename = line.Substring(nameBegin + 5).Replace("\"", string.Empty).Trim();
}
}
if (isAlternative && altBoundary.Length == 0)
{
if ((boundaryBegin = lowerLine.IndexOf("boundary=")) > 0)
{
altBoundary = line.Substring(boundaryBegin + 9).Replace("\"", string.Empty).Trim();
}
}
}
}
}
}
private void ProcessSinglePlainBody(string[] lines)
{
string filename = string.Empty;
bool inBody = true;
int partLen = 0;
string line;
for (int i = 0; i < lines.Length; ++i)
{
line = lines[i].TrimEnd('\r');
if (inBody && line.StartsWith("begin"))
{
string[] attachHeaders = line.TrimEnd(' ').Split(' ');
if (attachHeaders.Length > 2)
{
string fattr = attachHeaders[1];
bool fattrOk = fattr.Length >= 3;
if (fattrOk)
{
for (int j = 0; j < fattr.Length; ++j)
{
if (!(fattrOk = Char.IsDigit(fattr[j])))
{
break;
}
}
}
if (fattrOk)
{
filename = attachHeaders[2];
for (int j = 3; j < attachHeaders.Length; ++j)
{
filename += attachHeaders[j];
}
inBody = false;
partLen = 0;
continue;
}
}
}
else if (!inBody && line.StartsWith("end"))
{
if (_partBuilder.Length > 0)
{
if (partLen > 0)
{
byte[] bytes = UUParser.Decode(_partBuilder.ToString());
if (partLen > bytes.Length)
{
partLen = bytes.Length;
}
MessagePart attachment = new MessagePart(bytes, partLen, filename);
attachment.PartType = MessagePartTypes.Inline;
_parts.Add(attachment);
}
_partBuilder.Length = 0;
}
inBody = true;
continue;
}
if (inBody)
{
_bodyBuilder.Append(line);
_bodyBuilder.Append("\r\n");
}
else
{
if (line.Length > 1 && line[0] != '`')
{
partLen += UUParser._UUAlphabet.IndexOf(line[0]);
_partBuilder.Append(line, 1, line.Length - 1);
}
}
}
}