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mirror of https://github.com/moparisthebest/k-9 synced 2024-11-15 22:15:15 -05:00
k-9/src/com/fsck/k9/mail/internet/MimeUtility.java

416 lines
13 KiB
Java

package com.fsck.k9.mail.internet;
import android.util.Log;
import com.fsck.k9.K9;
import com.fsck.k9.mail.*;
import org.apache.commons.io.IOUtils;
import org.apache.james.mime4j.decoder.Base64InputStream;
import org.apache.james.mime4j.decoder.DecoderUtil;
import org.apache.james.mime4j.decoder.QuotedPrintableInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.regex.Pattern;
import java.nio.charset.Charset;
public class MimeUtility
{
public static final String DEFAULT_ATTACHMENT_MIME_TYPE = "application/octet-stream";
public static String unfold(String s)
{
if (s == null)
{
return null;
}
return s.replaceAll("\r|\n", "");
}
public static String decode(String s)
{
if (s == null)
{
return null;
}
return DecoderUtil.decodeEncodedWords(s);
}
public static String unfoldAndDecode(String s)
{
return decode(unfold(s));
}
// TODO implement proper foldAndEncode
public static String foldAndEncode(String s)
{
return s;
}
/**
* Returns the named parameter of a header field. If name is null the first
* parameter is returned, or if there are no additional parameters in the
* field the entire field is returned. Otherwise the named parameter is
* searched for in a case insensitive fashion and returned. If the parameter
* cannot be found the method returns null.
*
* @param header
* @param name
* @return
*/
public static String getHeaderParameter(String header, String name)
{
if (header == null)
{
return null;
}
header = header.replaceAll("\r|\n", "");
String[] parts = header.split(";");
if (name == null)
{
return parts[0];
}
for (String part : parts)
{
if (part.trim().toLowerCase().startsWith(name.toLowerCase()))
{
String parameter = part.split("=", 2)[1].trim();
if (parameter.startsWith("\"") && parameter.endsWith("\""))
{
return parameter.substring(1, parameter.length() - 1);
}
else
{
return parameter;
}
}
}
return null;
}
public static Part findFirstPartByMimeType(Part part, String mimeType)
throws MessagingException
{
if (part.getBody() instanceof Multipart)
{
Multipart multipart = (Multipart)part.getBody();
for (int i = 0, count = multipart.getCount(); i < count; i++)
{
BodyPart bodyPart = multipart.getBodyPart(i);
Part ret = findFirstPartByMimeType(bodyPart, mimeType);
if (ret != null)
{
return ret;
}
}
}
else if (part.getMimeType().equalsIgnoreCase(mimeType))
{
return part;
}
return null;
}
public static Part findPartByContentId(Part part, String contentId) throws Exception
{
if (part.getBody() instanceof Multipart)
{
Multipart multipart = (Multipart)part.getBody();
for (int i = 0, count = multipart.getCount(); i < count; i++)
{
BodyPart bodyPart = multipart.getBodyPart(i);
Part ret = findPartByContentId(bodyPart, contentId);
if (ret != null)
{
return ret;
}
}
}
String[] header = part.getHeader("Content-ID");
if (header != null)
{
for (String s : header)
{
if (s.equals(contentId))
{
return part;
}
}
}
return null;
}
/**
* Reads the Part's body and returns a String based on any charset conversion that needed
* to be done.
* @param part The part containing a body
* @return a String containing the converted text in the body, or null if there was no text
* or an error during conversion.
*/
public static String getTextFromPart(Part part)
{
try
{
if ((part != null) && (part.getBody() != null))
{
final Body body = part.getBody();
if (body instanceof TextBody)
{
return ((TextBody)body).getText();
}
final String mimeType = part.getMimeType();
if ((mimeType != null) && MimeUtility.mimeTypeMatches(mimeType, "text/*"))
{
/*
* We've got a text part, so let's see if it needs to be processed further.
*/
final String originalCharset = getHeaderParameter(part.getContentType(), "charset");
String charset = "ASCII"; // No encoding, so use us-ascii, which is the standard.
if ((originalCharset != null) && ("0".equals(originalCharset) == false))
{
/*
* See if there is conversion from the MIME charset to the Java one.
*/
charset = Charset.forName(fixupCharset(originalCharset)).name();
if (charset == null)
{
Log.e(K9.LOG_TAG,"I don't know how to deal with the charset "+originalCharset+". Falling back to US-ASCII");
charset = "US-ASCII";
}
}
/*
* Now we read the part into a buffer for further processing. Because
* the stream is now wrapped we'll remove any transfer encoding at this point.
*/
InputStream in = part.getBody().getInputStream();
ByteArrayOutputStream out = new ByteArrayOutputStream(in.available());
IOUtils.copy(in, out);
in.close();
in = null; // we want all of our memory back, and close might not release
// Cargo culted from AOSP - This disagrees with the platform docs
/*
* Convert and return as new String
*/
final String result = out.toString(charset);
out.close();
return result;
}
}
}
catch (OutOfMemoryError oom)
{
/*
* If we are not able to process the body there's nothing we can do about it. Return
* null and let the upper layers handle the missing content.
*/
Log.e(K9.LOG_TAG, "Unable to getTextFromPart " + oom.toString());
}
catch (Exception e)
{
/*
* If we are not able to process the body there's nothing we can do about it. Return
* null and let the upper layers handle the missing content.
*/
Log.e(K9.LOG_TAG, "Unable to getTextFromPart", e);
}
return null;
}
/**
* Returns true if the given mimeType matches the matchAgainst specification.
* @param mimeType A MIME type to check.
* @param matchAgainst A MIME type to check against. May include wildcards such as image/* or
* * /*.
* @return
*/
public static boolean mimeTypeMatches(String mimeType, String matchAgainst)
{
Pattern p = Pattern.compile(matchAgainst.replaceAll("\\*", "\\.\\*"),
Pattern.CASE_INSENSITIVE);
return p.matcher(mimeType).matches();
}
/**
* Returns true if the given mimeType matches any of the matchAgainst specifications.
* @param mimeType A MIME type to check.
* @param matchAgainst An array of MIME types to check against. May include wildcards such
* as image/* or * /*.
* @return
*/
public static boolean mimeTypeMatches(String mimeType, String[] matchAgainst)
{
for (String matchType : matchAgainst)
{
if (mimeTypeMatches(mimeType, matchType))
{
return true;
}
}
return false;
}
/**
* Removes any content transfer encoding from the stream and returns a Body.
*/
public static Body decodeBody(InputStream in, String contentTransferEncoding)
throws IOException
{
/*
* We'll remove any transfer encoding by wrapping the stream.
*/
if (contentTransferEncoding != null)
{
contentTransferEncoding =
MimeUtility.getHeaderParameter(contentTransferEncoding, null);
if ("quoted-printable".equalsIgnoreCase(contentTransferEncoding))
{
in = new QuotedPrintableInputStream(in);
}
else if ("base64".equalsIgnoreCase(contentTransferEncoding))
{
in = new Base64InputStream(in);
}
}
BinaryTempFileBody tempBody = new BinaryTempFileBody();
OutputStream out = tempBody.getOutputStream();
IOUtils.copy(in, out);
out.close();
return tempBody;
}
/**
* An unfortunately named method that makes decisions about a Part (usually a Message)
* as to which of it's children will be "viewable" and which will be attachments.
* The method recursively sorts the viewables and attachments into seperate
* lists for further processing.
* @param part
* @param viewables
* @param attachments
* @throws MessagingException
*/
public static void collectParts(Part part, ArrayList<Part> viewables,
ArrayList<Part> attachments) throws MessagingException
{
/*
* If the part is Multipart but not alternative it's either mixed or
* something we don't know about, which means we treat it as mixed
* per the spec. We just process it's pieces recursively.
*/
if (part.getBody() instanceof Multipart)
{
Multipart mp = (Multipart)part.getBody();
for (int i = 0; i < mp.getCount(); i++)
{
collectParts(mp.getBodyPart(i), viewables, attachments);
}
}
/*
* If the part is an embedded message we just continue to process
* it, pulling any viewables or attachments into the running list.
*/
else if (part.getBody() instanceof Message)
{
Message message = (Message)part.getBody();
collectParts(message, viewables, attachments);
}
/*
* If the part is HTML and it got this far it's part of a mixed (et
* al) and should be rendered inline.
*/
else if (isPartTextualBody(part))
{
viewables.add(part);
}
else
{
attachments.add(part);
}
}
public static Boolean isPartTextualBody(Part part) throws MessagingException
{
String disposition = part.getDisposition();
String dispositionType = null;
String dispositionFilename = null;
if (disposition != null)
{
dispositionType = MimeUtility.getHeaderParameter(disposition, null);
dispositionFilename = MimeUtility.getHeaderParameter(disposition, "filename");
}
/*
* A best guess that this part is intended to be an attachment and not inline.
*/
boolean attachment = ("attachment".equalsIgnoreCase(dispositionType)
|| (dispositionFilename != null));
if ((!attachment) && (part.getMimeType().equalsIgnoreCase("text/html")))
{
return true;
}
/*
* If the part is plain text and it got this far it's part of a
* mixed (et al) and should be rendered inline.
*/
else if ((!attachment) && (part.getMimeType().equalsIgnoreCase("text/plain")))
{
return true;
}
/*
* Finally, if it's nothing else we will include it as an attachment.
*/
else
{
return false;
}
}
public static String getMimeTypeByExtension(String filename)
{
String returnedType = null;
if (filename != null
&& filename.lastIndexOf('.') != -1)
{
String extension = filename.substring(filename.lastIndexOf('.')+1).toLowerCase();
returnedType = android.webkit.MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
}
if (returnedType != null)
{
return returnedType;
}
else
{
return DEFAULT_ATTACHMENT_MIME_TYPE;
}
}
private static String fixupCharset(String charset)
{
charset = charset.toLowerCase();
if (charset.equals("cp932"))
return "shift-jis";
else if (charset.equals("koi8-u"))
return "koi8-r";
return charset;
}
}