path: root/mailnews/imap/src/nsIMAPBodyShell.cpp

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "msgCore.h"
#include "nsIMAPHostSessionList.h"
#include "nsIMAPBodyShell.h"
#include "nsImapProtocol.h"
#include "nsImapStringBundle.h"

#include "nsMimeTypes.h"
#include "nsIPrefBranch.h"
#include "nsIPrefService.h"
#include "nsITransport.h"
#include "nsServiceManagerUtils.h"

// need to talk to Rich about this...
#define IMAP_EXTERNAL_CONTENT_HEADER "X-Mozilla-IMAP-Part"

// imapbody.cpp
// Implementation of the nsIMAPBodyShell and associated classes
// These are used to parse IMAP BODYSTRUCTURE responses, and intelligently (?)
// figure out what parts we need to display inline.

/*
        Create a nsIMAPBodyShell from a full BODYSTRUCUTRE response from the parser.

        The body shell represents a single, top-level object, the message.  The message body
        might be treated as either a container or a leaf (just like any arbitrary part).

        Steps for creating a part:
        1. Pull out the paren grouping for the part
        2. Create a generic part object with that buffer
        3. The factory will return either a leaf or container, depending on what it really is.
        4. It is responsible for parsing its children, if there are any
*/


///////////// nsIMAPBodyShell ////////////////////////////////////

NS_IMPL_ISUPPORTS0(nsIMAPBodyShell)

nsIMAPBodyShell::nsIMAPBodyShell(nsImapProtocol *protocolConnection,
                                 nsIMAPBodypartMessage *message, uint32_t UID,
                                 const char *folderName)
{
  m_isValid = false;
  m_isBeingGenerated = false;
  m_cached = false;
  m_gotAttachmentPref = false;
  m_generatingWholeMessage = false;
  m_generatingPart = NULL;
  m_protocolConnection = protocolConnection;
  m_message = message;
  NS_ASSERTION(m_protocolConnection, "non null connection");
  if (!m_protocolConnection)
    return;
  m_prefetchQueue = new nsIMAPMessagePartIDArray();
  if (!m_prefetchQueue)
    return;
  m_UID = "";
  m_UID.AppendInt(UID);
#ifdef DEBUG_chrisf
  NS_ASSERTION(folderName);
#endif
  if (!folderName)
    return;
  m_folderName = NS_strdup(folderName);
  if (!m_folderName)
    return;
  
  SetContentModified(GetShowAttachmentsInline() ? IMAP_CONTENT_MODIFIED_VIEW_INLINE : IMAP_CONTENT_MODIFIED_VIEW_AS_LINKS);

  SetIsValid(m_message != nullptr);
}

nsIMAPBodyShell::~nsIMAPBodyShell()
{
  delete m_message;
  delete m_prefetchQueue;
  PR_Free(m_folderName);
}

void nsIMAPBodyShell::SetIsValid(bool valid)
{
  m_isValid = valid;
}

bool nsIMAPBodyShell::GetShowAttachmentsInline()
{
  if (!m_gotAttachmentPref)
  {
    m_showAttachmentsInline = !m_protocolConnection || m_protocolConnection->GetShowAttachmentsInline();
    m_gotAttachmentPref = true;
  }
  
  return m_showAttachmentsInline;
}

// Fills in buffer (and adopts storage) for header object
void nsIMAPBodyShell::AdoptMessageHeaders(char *headers, const char *partNum)
{
  if (!GetIsValid())
    return;
  
  if (!partNum)
    partNum = "0";
  
  // we are going to say that a message header object only has
  // part data, and no header data.
  nsIMAPBodypart *foundPart = m_message->FindPartWithNumber(partNum);
  if (foundPart)
  {
    nsIMAPBodypartMessage *messageObj = foundPart->GetnsIMAPBodypartMessage();
    if (messageObj)
    {
      messageObj->AdoptMessageHeaders(headers);
      if (!messageObj->GetIsValid())
        SetIsValid(false);
    }
    else
    {
      // We were filling in message headers for a given part number.
      // We looked up that part number, found an object, but it
      // wasn't of type message/rfc822.
      // Something's wrong.
      NS_ASSERTION(false, "object not of type message rfc822");
    }
  }
  else
    SetIsValid(false);
}

// Fills in buffer (and adopts storage) for MIME headers in appropriate object.
// If object can't be found, sets isValid to false.
void nsIMAPBodyShell::AdoptMimeHeader(const char *partNum, char *mimeHeader)
{
  if (!GetIsValid())
    return;
  
  NS_ASSERTION(partNum, "null partnum in body shell");
  
  nsIMAPBodypart *foundPart = m_message->FindPartWithNumber(partNum);
  
  if (foundPart)
  {
    foundPart->AdoptHeaderDataBuffer(mimeHeader);
    if (!foundPart->GetIsValid())
      SetIsValid(false);
  }
  else
  {
    SetIsValid(false);
  }
}


void nsIMAPBodyShell::AddPrefetchToQueue(nsIMAPeFetchFields fields, const char *partNumber)
{
  nsIMAPMessagePartID *newPart = new nsIMAPMessagePartID(fields, partNumber);
  if (newPart)
  {
    m_prefetchQueue->AppendElement(newPart);
  }
  else
  {
    // HandleMemoryFailure();
  }
}

// Flushes all of the prefetches that have been queued up in the prefetch queue,
// freeing them as we go
void nsIMAPBodyShell::FlushPrefetchQueue()
{
  m_protocolConnection->PipelinedFetchMessageParts(GetUID(), m_prefetchQueue);
  m_prefetchQueue->RemoveAndFreeAll();
}

// Requires that the shell is valid when called
// Performs a preflight check on all message parts to see if they are all
// inline.  Returns true if all parts are inline, false otherwise.
bool nsIMAPBodyShell::PreflightCheckAllInline()
{
  bool rv = m_message->PreflightCheckAllInline(this);
  //	if (rv)
  //		MOZ_LOG(IMAP, out, ("BODYSHELL: All parts inline.  Reverting to whole message download."));
  return rv;
}

// When partNum is NULL, Generates a whole message and intelligently
// leaves out parts that are not inline.

// When partNum is not NULL, Generates a MIME part that hasn't been downloaded yet
// Ok, here's how we're going to do this.  Essentially, this
// will be the mirror image of the "normal" generation.
// All parts will be left out except a single part which is
// explicitly specified.  All relevant headers will be included.
// Libmime will extract only the part of interest, so we don't
// have to worry about the other parts.  This also has the
// advantage that it looks like it will be more workable for
// nested parts.  For instance, if a user clicks on a link to
// a forwarded message, then that forwarded message may be 
// generated along with any images that the forwarded message
// contains, for instance.


int32_t nsIMAPBodyShell::Generate(char *partNum)
{
  m_isBeingGenerated = true;
  m_generatingPart = partNum;
  int32_t contentLength = 0;
  
  if (!GetIsValid() || PreflightCheckAllInline())
  {
    // We don't have a valid shell, or all parts are going to be inline anyway.  Fall back to fetching the whole message.
#ifdef DEBUG_chrisf
    NS_ASSERTION(GetIsValid());
#endif
    m_generatingWholeMessage = true;
    uint32_t messageSize = m_protocolConnection->GetMessageSize(GetUID().get(), true);
    m_protocolConnection->SetContentModified(IMAP_CONTENT_NOT_MODIFIED);	// So that when we cache it, we know we have the whole message
    if (!DeathSignalReceived())
      m_protocolConnection->FallbackToFetchWholeMsg(GetUID(), messageSize);
    contentLength = (int32_t) messageSize;	// ugh
  }
  else
  {
    // We have a valid shell.
    bool streamCreated = false;
    m_generatingWholeMessage = false;
    
    ////// PASS 1 : PREFETCH ///////
    // First, prefetch any additional headers/data that we need
    if (!GetPseudoInterrupted())
      m_message->Generate(this, false, true); // This queues up everything we need to prefetch
    // Now, run a single pipelined prefetch  (neato!)
    FlushPrefetchQueue();
    
    ////// PASS 2 : COMPUTE STREAM SIZE ///////
    // Next, figure out the size from the parts that we're going to fill in,
    // plus all of the MIME headers, plus the message header itself
    if (!GetPseudoInterrupted())
      contentLength = m_message->Generate(this, false, false);
    
    // Setup the stream
    if (!GetPseudoInterrupted() && !DeathSignalReceived())
    {
      nsresult rv = 
        m_protocolConnection->BeginMessageDownLoad(contentLength, MESSAGE_RFC822);
      if (NS_FAILED(rv))
      {
        m_generatingPart = nullptr;
        m_protocolConnection->AbortMessageDownLoad();
        return 0;
      }
      else
      {
        streamCreated = true;
      }
    }
    
    ////// PASS 3 : GENERATE ///////
    // Generate the message
    if (!GetPseudoInterrupted() && !DeathSignalReceived())
      m_message->Generate(this, true, false);
    
    // Close the stream here - normal.  If pseudointerrupted, the connection will abort the download stream
    if (!GetPseudoInterrupted() && !DeathSignalReceived())
      m_protocolConnection->NormalMessageEndDownload();
    else if (streamCreated)
      m_protocolConnection->AbortMessageDownLoad();
    
    m_generatingPart = NULL;
    
  }
  
  m_isBeingGenerated = false;
  return contentLength;
}

bool nsIMAPBodyShell::GetPseudoInterrupted()
{
  bool rv = m_protocolConnection->GetPseudoInterrupted();
  return rv;
}

bool nsIMAPBodyShell::DeathSignalReceived()
{
  bool rv = m_protocolConnection->DeathSignalReceived();
  return rv;
}


///////////// nsIMAPBodypart ////////////////////////////////////

nsIMAPBodypart::nsIMAPBodypart(char *partNumber, nsIMAPBodypart *parentPart)
{
  SetIsValid(true);
  m_parentPart = parentPart;
  m_partNumberString = partNumber;	// storage adopted
  m_partData = NULL;
  m_headerData = NULL;
  m_boundaryData = NULL;	// initialize from parsed BODYSTRUCTURE
  m_contentLength = 0;
  m_partLength = 0;
  
  m_contentType = NULL;
  m_bodyType = NULL;
  m_bodySubType = NULL;
  m_bodyID = NULL;
  m_bodyDescription = NULL;
  m_bodyEncoding = NULL;
}

nsIMAPBodypart::~nsIMAPBodypart()
{
  PR_FREEIF(m_partNumberString);
  PR_FREEIF(m_contentType);
  PR_FREEIF(m_bodyType);
  PR_FREEIF(m_bodySubType);
  PR_FREEIF(m_bodyID);
  PR_FREEIF(m_bodyDescription);
  PR_FREEIF(m_bodyEncoding);
  PR_FREEIF(m_partData);
  PR_FREEIF(m_headerData);
  PR_FREEIF(m_boundaryData);
}

void nsIMAPBodypart::SetIsValid(bool valid)
{
  m_isValid = valid;
  if (!m_isValid)
  {
    //MOZ_LOG(IMAP, out, ("BODYSHELL: Part is invalid.  Part Number: %s Content-Type: %s", m_partNumberString, m_contentType));
  }
}

// Adopts storage for part data buffer.  If NULL, sets isValid to false.
void nsIMAPBodypart::AdoptPartDataBuffer(char *buf)
{
  m_partData = buf;
  if (!m_partData)
  {
    SetIsValid(false);
  }
}

// Adopts storage for header data buffer.  If NULL, sets isValid to false.
void nsIMAPBodypart::AdoptHeaderDataBuffer(char *buf)
{
  m_headerData = buf;
  if (!m_headerData)
  {
    SetIsValid(false);
  }
}

// Finds the part with given part number
// Returns a nsIMAPBodystructure of the matched part if it is this
// or one of its children.  Returns NULL otherwise.
nsIMAPBodypart *nsIMAPBodypart::FindPartWithNumber(const char *partNum)
{
  // either brute force, or do it the smart way - look at the number.
  // (the parts should be ordered, and hopefully indexed by their number)
  
  if (m_partNumberString && !PL_strcasecmp(partNum, m_partNumberString))
    return this;
  
  //if (!m_partNumberString && !PL_strcasecmp(partNum, "1"))
  //	return this;
  
  return NULL;
}

/*
void nsIMAPBodypart::PrefetchMIMEHeader()
{
if (!m_headerData && !m_shell->DeathSignalReceived())
{
m_shell->GetConnection()->FetchMessage(m_shell->GetUID(), kMIMEHeader, true, 0, 0, m_partNumberString);
// m_headerLength will be filled in when it is adopted from the parser
}
if (!m_headerData)
{
SetIsValid(false);
}
}
*/

void nsIMAPBodypart::QueuePrefetchMIMEHeader(nsIMAPBodyShell *aShell)
{
  aShell->AddPrefetchToQueue(kMIMEHeader, m_partNumberString);
}

int32_t nsIMAPBodypart::GenerateMIMEHeader(nsIMAPBodyShell *aShell, bool stream, bool prefetch)
{
  if (prefetch && !m_headerData)
  {
    QueuePrefetchMIMEHeader(aShell);
    return 0;
  }
  else if (m_headerData)
  {
    int32_t mimeHeaderLength = 0;
    
    if (!ShouldFetchInline(aShell))
    {
      // if this part isn't inline, add the X-Mozilla-IMAP-Part header
      char *xPartHeader = PR_smprintf("%s: %s", IMAP_EXTERNAL_CONTENT_HEADER, m_partNumberString);
      if (xPartHeader)
      {
        if (stream)
        {
          aShell->GetConnection()->Log("SHELL","GENERATE-XHeader",m_partNumberString);
          aShell->GetConnection()->HandleMessageDownLoadLine(xPartHeader, false);
        }
        mimeHeaderLength += PL_strlen(xPartHeader);
        PR_Free(xPartHeader);
      }
    }
    
    mimeHeaderLength += PL_strlen(m_headerData);
    if (stream)
    {
      aShell->GetConnection()->Log("SHELL","GENERATE-MIMEHeader",m_partNumberString);
      aShell->GetConnection()->HandleMessageDownLoadLine(m_headerData, false);  // all one line?  Can we do that?
    }
    
    return mimeHeaderLength;
  }
  else 
  {
    SetIsValid(false);	// prefetch didn't adopt a MIME header
    return 0;
  }
}

int32_t nsIMAPBodypart::GeneratePart(nsIMAPBodyShell *aShell, bool stream, bool prefetch)
{
  if (prefetch)
    return 0;	// don't need to prefetch anything
  
  if (m_partData)	// we have prefetched the part data
  {
    if (stream)
    {
      aShell->GetConnection()->Log("SHELL","GENERATE-Part-Prefetched",m_partNumberString);
      aShell->GetConnection()->HandleMessageDownLoadLine(m_partData, false);
    }
    return PL_strlen(m_partData);
  }
  else	// we are fetching and streaming this part's body as we go
  {
    if (stream && !aShell->DeathSignalReceived())
    {
      char *generatingPart = aShell->GetGeneratingPart();
      bool fetchingSpecificPart = (generatingPart && !PL_strcmp(generatingPart, m_partNumberString));
      
      aShell->GetConnection()->Log("SHELL","GENERATE-Part-Inline",m_partNumberString);
      aShell->GetConnection()->FetchTryChunking(aShell->GetUID(), kMIMEPart, true, m_partNumberString, m_partLength, !fetchingSpecificPart);
    }
    return m_partLength;	// the part length has been filled in from the BODYSTRUCTURE response
  }
}

int32_t nsIMAPBodypart::GenerateBoundary(nsIMAPBodyShell *aShell, bool stream, bool prefetch, bool lastBoundary)
{
  if (prefetch)
    return 0;	// don't need to prefetch anything
  
  if (m_boundaryData)
  {
    if (!lastBoundary)
    {
      if (stream)
      {
        aShell->GetConnection()->Log("SHELL","GENERATE-Boundary",m_partNumberString);
        aShell->GetConnection()->HandleMessageDownLoadLine(m_boundaryData, false);
      }
      return PL_strlen(m_boundaryData);
    }
    else	// the last boundary
    {
      char *lastBoundaryData = PR_smprintf("%s--", m_boundaryData);
      if (lastBoundaryData)
      {
        if (stream)
        {
          aShell->GetConnection()->Log("SHELL","GENERATE-Boundary-Last",m_partNumberString);
          aShell->GetConnection()->HandleMessageDownLoadLine(lastBoundaryData, false);
        }
        int32_t rv = PL_strlen(lastBoundaryData);
        PR_Free(lastBoundaryData);
        return rv;
      }
      else
      {
        //HandleMemoryFailure();
        return 0;
      }
    }
  }
  else
    return 0;
}

int32_t nsIMAPBodypart::GenerateEmptyFilling(nsIMAPBodyShell *aShell, bool stream, bool prefetch)
{
  if (prefetch)
    return 0; // don't need to prefetch anything

  const nsString &emptyString = aShell->GetConnection()->
    GetEmptyMimePartString();
  if (!emptyString.IsEmpty())
  {
    if (stream)
    {
      nsImapProtocol *conn = aShell->GetConnection();
      conn->Log("SHELL", "GENERATE-Filling", m_partNumberString);
      conn->HandleMessageDownLoadLine(NS_ConvertUTF16toUTF8(emptyString).get(),
                                      false);
    }
    return emptyString.Length();
  }
  else
    return 0;
}


// Returns true if the prefs say that this content type should
// explicitly be kept in when filling in the shell
bool nsIMAPBodypart::ShouldExplicitlyFetchInline()
{
	 return false;
}


// Returns true if the prefs say that this content type should
// explicitly be left out when filling in the shell
bool nsIMAPBodypart::ShouldExplicitlyNotFetchInline()
{
  return false;
}


///////////// nsIMAPBodypartLeaf /////////////////////////////


nsIMAPBodypartLeaf::nsIMAPBodypartLeaf(char *partNum,
                                       nsIMAPBodypart *parentPart,
                                       char *bodyType, char *bodySubType,
                                       char *bodyID, char *bodyDescription,
                                       char *bodyEncoding, int32_t partLength,
                                       bool preferPlainText)
  : nsIMAPBodypart(partNum, parentPart), mPreferPlainText(preferPlainText)
{
  m_bodyType = bodyType;
  m_bodySubType = bodySubType;
  m_bodyID = bodyID;
  m_bodyDescription = bodyDescription;
  m_bodyEncoding = bodyEncoding;
  m_partLength = partLength;
  if (m_bodyType && m_bodySubType)
  {
    m_contentType = PR_smprintf("%s/%s", m_bodyType, m_bodySubType);
  }
  SetIsValid(true);
}

nsIMAPBodypartType nsIMAPBodypartLeaf::GetType()
{
  return IMAP_BODY_LEAF;
}

int32_t nsIMAPBodypartLeaf::Generate(nsIMAPBodyShell *aShell, bool stream, bool prefetch)
{
  int32_t len = 0;
  
  if (GetIsValid())
  {
    
    if (stream && !prefetch)
      aShell->GetConnection()->Log("SHELL","GENERATE-Leaf",m_partNumberString);
    
    // Stream out the MIME part boundary
    //GenerateBoundary();
    NS_ASSERTION(m_parentPart, "part has no parent");
    //nsIMAPBodypartMessage *parentMessage = m_parentPart ? m_parentPart->GetnsIMAPBodypartMessage() : NULL;
    
    // Stream out the MIME header of this part, if this isn't the only body part of a message
    //if (parentMessage ? !parentMessage->GetIsTopLevelMessage() : true)
    if ((m_parentPart->GetType() != IMAP_BODY_MESSAGE_RFC822)
      && !aShell->GetPseudoInterrupted())
      len += GenerateMIMEHeader(aShell, stream, prefetch);
    
    if (!aShell->GetPseudoInterrupted())
    {
      if (ShouldFetchInline(aShell))
      {
        // Fetch and stream the content of this part
        len += GeneratePart(aShell, stream, prefetch);
      }
      else
      {
        // fill in the filling within the empty part
        len += GenerateEmptyFilling(aShell, stream, prefetch);
      }
    }
  }
  m_contentLength = len;
  return m_contentLength;
}



// returns true if this part should be fetched inline for generation.
bool nsIMAPBodypartLeaf::ShouldFetchInline(nsIMAPBodyShell *aShell)
{
  char *generatingPart = aShell->GetGeneratingPart();
  if (generatingPart)
  {
    // If we are generating a specific part
    if (!PL_strcmp(generatingPart, m_partNumberString))
    {
      // This is the part we're generating
      return true;
    }
    else
    {
      // If this is the only body part of a message, and that
      // message is the part being generated, then this leaf should
      // be inline as well.
      if ((m_parentPart->GetType() == IMAP_BODY_MESSAGE_RFC822) &&
        (!PL_strcmp(m_parentPart->GetPartNumberString(), generatingPart)))
        return true;
      
      // The parent of this part is a multipart
      if (m_parentPart->GetType() == IMAP_BODY_MULTIPART)
      {
        // This is the first text part of a forwarded message
        // with a multipart body, and that message is being generated,
        // then generate this part.
        nsIMAPBodypart *grandParent = m_parentPart->GetParentPart();
        // grandParent must exist, since multiparts need parents
        NS_ASSERTION(grandParent, "grandparent doesn't exist for multi-part alt");
        if (grandParent && 
          (grandParent->GetType() == IMAP_BODY_MESSAGE_RFC822) &&
          (!PL_strcmp(grandParent->GetPartNumberString(), generatingPart)) &&
          (m_partNumberString[PL_strlen(m_partNumberString)-1] == '1') &&
          !PL_strcasecmp(m_bodyType, "text"))
          return true;	// we're downloading it inline
        
        
        // This is a child of a multipart/appledouble attachment,
        // and that multipart/appledouble attachment is being generated
        if (m_parentPart &&
          !PL_strcasecmp(m_parentPart->GetBodySubType(), "appledouble") &&
          !PL_strcmp(m_parentPart->GetPartNumberString(), generatingPart))
          return true;	// we're downloading it inline
      }
      
      // Leave out all other leaves if this isn't the one
      // we're generating.
      // Maybe change later to check parents, etc.
      return false;
    }
  }
  else
  {
    // We are generating the whole message, possibly (hopefully)
    // leaving out non-inline parts
    
    if (ShouldExplicitlyFetchInline())
      return true;
    if (ShouldExplicitlyNotFetchInline())
      return false;
    
    // If the parent is a message (this is the only body part of that
    // message), and that message should be inline, then its body
    // should inherit the inline characteristics of that message
    if (m_parentPart->GetType() == IMAP_BODY_MESSAGE_RFC822)
      return m_parentPart->ShouldFetchInline(aShell);
    
    // View Attachments As Links is on.
    if (!(aShell->GetContentModified() == IMAP_CONTENT_MODIFIED_VIEW_INLINE))
    {
      // The last text part is still displayed inline,
      // even if View Attachments As Links is on.
      nsIMAPBodypart *grandParentPart = m_parentPart->GetParentPart();
      if ((mPreferPlainText ||
           !PL_strcasecmp(m_parentPart->GetBodySubType(), "mixed")) &&
          !PL_strcmp(m_partNumberString, "1") &&
          !PL_strcasecmp(m_bodyType, "text"))
        return true;         // we're downloading it inline

      if ((!PL_strcasecmp(m_parentPart->GetBodySubType(), "alternative") ||
           (grandParentPart &&
            !PL_strcasecmp(grandParentPart->GetBodySubType(), "alternative"))) &&
          !PL_strcasecmp(m_bodyType, "text") &&
          ((!PL_strcasecmp(m_bodySubType, "plain") && mPreferPlainText) ||
           (!PL_strcasecmp(m_bodySubType, "html") && !mPreferPlainText)))
        return true;

      // This is the first text part of a top-level multipart.
      // For instance, a message with multipart body, where the first
      // part is multipart, and this is the first leaf of that first part.
      if (m_parentPart->GetType() == IMAP_BODY_MULTIPART &&
          (PL_strlen(m_partNumberString) >= 2) &&
          !PL_strcmp(m_partNumberString + PL_strlen(m_partNumberString) - 2, ".1") && // this is the first text type on this level
          (!PL_strcmp(m_parentPart->GetPartNumberString(), "1") || !PL_strcmp(m_parentPart->GetPartNumberString(), "2")) && 
          !PL_strcasecmp(m_bodyType, "text"))
        return true;
      // This is the first text part of a top-level multipart of the toplevelmessage
      // This 'assumes' the text body is first leaf. This is not required for valid email.
      // The only other way is to get content-disposition = attachment and exclude those text parts.
      if (m_parentPart->GetType() == IMAP_BODY_MULTIPART &&
          !PL_strcasecmp(m_bodyType, "text") &&
          !PL_strcmp(m_parentPart->GetPartNumberString(), "0") &&
          !PL_strcmp(m_partNumberString, "1"))
         return true;

      // we may have future problems needing tests here

      return false;  // we can leave it on the server
    }
    
    // Leave out parts with type application/(*)
    if (!PL_strcasecmp(m_bodyType, "APPLICATION") &&	// If it is of type "application"
      PL_strncasecmp(m_bodySubType, "x-pkcs7", 7)	// and it's not a signature (signatures are inline)
      )
      return false;	// we can leave it on the server
    if (!PL_strcasecmp(m_bodyType, "AUDIO"))
      return false;
    // Here's where we can add some more intelligence -- let's leave out
    // any other parts that we know we can't display inline.
    return true;	// we're downloading it inline
  }
}



bool nsIMAPBodypartMultipart::IsLastTextPart(const char *partNumberString)
{
 // iterate backwards over the parent's part list and if the part is
  // text, compare it to the part number string
  for (int i = m_partList->Length() - 1; i >= 0; i--)
  {
      nsIMAPBodypart *part = m_partList->ElementAt(i);
      if (!PL_strcasecmp(part->GetBodyType(), "text"))
        return !PL_strcasecmp(part->GetPartNumberString(), partNumberString);
  }
  return false;
}

bool nsIMAPBodypartLeaf::PreflightCheckAllInline(nsIMAPBodyShell *aShell)
{
  // only need to check this part, since it has no children.
  return ShouldFetchInline(aShell);
}


///////////// nsIMAPBodypartMessage ////////////////////////

nsIMAPBodypartMessage::nsIMAPBodypartMessage(char *partNum,
                                             nsIMAPBodypart *parentPart,
                                             bool topLevelMessage,
                                             char *bodyType, char *bodySubType,
                                             char *bodyID,
                                             char *bodyDescription,
                                             char *bodyEncoding,
                                             int32_t partLength,
                                             bool preferPlainText)
 : nsIMAPBodypartLeaf(partNum, parentPart, bodyType, bodySubType, bodyID,
                      bodyDescription, bodyEncoding, partLength,
                      preferPlainText)
{
  m_topLevelMessage = topLevelMessage;
  if (m_topLevelMessage)
  {
    m_partNumberString = PR_smprintf("0");
    if (!m_partNumberString)
    {
      SetIsValid(false);
      return;
    }
  }
  m_body = NULL;
  m_headers = new nsIMAPMessageHeaders(m_partNumberString, this);  // We always have a Headers object
  if (!m_headers || !m_headers->GetIsValid())
  {
    SetIsValid(false);
    return;
  }
  SetIsValid(true);
}

void nsIMAPBodypartMessage::SetBody(nsIMAPBodypart *body)
{
  if (m_body)
    delete m_body;
  m_body = body;
}


nsIMAPBodypartType nsIMAPBodypartMessage::GetType()
{
  return IMAP_BODY_MESSAGE_RFC822;
}

nsIMAPBodypartMessage::~nsIMAPBodypartMessage()
{
  delete m_headers;
  delete m_body;
}

int32_t nsIMAPBodypartMessage::Generate(nsIMAPBodyShell *aShell, bool stream, bool prefetch)
{
  if (!GetIsValid())
    return 0;
  
  m_contentLength = 0;
  
  if (stream && !prefetch)
    aShell->GetConnection()->Log("SHELL","GENERATE-MessageRFC822",m_partNumberString);
  
  if (!m_topLevelMessage && !aShell->GetPseudoInterrupted())  // not the top-level message - we need the MIME header as well as the message header
  {
    // but we don't need the MIME headers of a message/rfc822 part if this content
    // type is in (part of) the main msg header. In other words, we still need
    // these MIME headers if this message/rfc822 body part is enclosed in the msg
    // body (most likely as a body part of a multipart/mixed msg).
    //       Don't fetch (bug 128888)              Do fetch (bug 168097)
    //  ----------------------------------  -----------------------------------
    //  message/rfc822  (parent part)       message/rfc822
    //   message/rfc822 <<<---               multipart/mixed  (parent part)
    //    multipart/mixed                     message/rfc822  <<<---
    //     text/html   (body text)             multipart/mixed
    //     text/plain  (attachment)             text/html   (body text)
    //     application/msword (attachment)      text/plain  (attachment)
    //                                          application/msword (attachment)
    // "<<<---" points to the part we're examining here.
    if ( PL_strcasecmp(m_bodyType, "message") || PL_strcasecmp(m_bodySubType, "rfc822") ||
      PL_strcasecmp(m_parentPart->GetBodyType(), "message") || PL_strcasecmp(m_parentPart->GetBodySubType(), "rfc822") )
      m_contentLength += GenerateMIMEHeader(aShell, stream, prefetch);
  }
  
  if (!aShell->GetPseudoInterrupted())
    m_contentLength += m_headers->Generate(aShell, stream, prefetch);
  if (!aShell->GetPseudoInterrupted())
    m_contentLength += m_body->Generate(aShell, stream, prefetch);
  
  return m_contentLength;
}




bool nsIMAPBodypartMessage::ShouldFetchInline(nsIMAPBodyShell *aShell)
{
  if (m_topLevelMessage)	// the main message should always be defined as "inline"
    return true;
  
  char *generatingPart = aShell->GetGeneratingPart();
  if (generatingPart)
  {
    // If we are generating a specific part
    // Always generate containers (just don't fill them in)
    // because it is low cost (everything is cached)
    // and it gives the message its full MIME structure,
    // to avoid any potential mishap.
    return true;
  }
  else
  {
    // Generating whole message
    
    if (ShouldExplicitlyFetchInline())
      return true;
    if (ShouldExplicitlyNotFetchInline())
      return false;
    
    
    // Message types are inline, by default.
    return true;
  }
}

bool nsIMAPBodypartMessage::PreflightCheckAllInline(nsIMAPBodyShell *aShell)
{
  if (!ShouldFetchInline(aShell))
    return false;
  
  return m_body->PreflightCheckAllInline(aShell);
}

// Fills in buffer (and adopts storage) for header object
void nsIMAPBodypartMessage::AdoptMessageHeaders(char *headers)
{
  if (!GetIsValid())
    return;
  
  // we are going to say that the message headers only have
  // part data, and no header data.
  m_headers->AdoptPartDataBuffer(headers);
  if (!m_headers->GetIsValid())
    SetIsValid(false);
}

// Finds the part with given part number
// Returns a nsIMAPBodystructure of the matched part if it is this
// or one of its children.  Returns NULL otherwise.
nsIMAPBodypart *nsIMAPBodypartMessage::FindPartWithNumber(const char *partNum)
{
  // either brute force, or do it the smart way - look at the number.
  // (the parts should be ordered, and hopefully indexed by their number)
  
  if (!PL_strcasecmp(partNum, m_partNumberString))
    return this;
  
  return m_body->FindPartWithNumber(partNum);
}

///////////// nsIMAPBodypartMultipart ////////////////////////


nsIMAPBodypartMultipart::nsIMAPBodypartMultipart(char *partNum, nsIMAPBodypart *parentPart) : 
nsIMAPBodypart(partNum, parentPart)
{
  if (!m_parentPart  || (m_parentPart->GetType() == IMAP_BODY_MESSAGE_RFC822))
  {
    // the multipart (this) will inherit the part number of its parent
    PR_FREEIF(m_partNumberString);
    if (!m_parentPart)
    {
      m_partNumberString = PR_smprintf("0");
    }
    else
      m_partNumberString = NS_strdup(m_parentPart->GetPartNumberString());
  }
  m_partList = new nsTArray<nsIMAPBodypart*>();
  m_bodyType = NS_strdup("multipart");
  if (m_partList && m_parentPart && m_bodyType)
    SetIsValid(true);
  else
    SetIsValid(false);
}

nsIMAPBodypartType nsIMAPBodypartMultipart::GetType()
{
  return IMAP_BODY_MULTIPART;
}

nsIMAPBodypartMultipart::~nsIMAPBodypartMultipart()
{
  for (int i = m_partList->Length() - 1; i >= 0; i--)
  {
    delete m_partList->ElementAt(i);
  }
  delete m_partList;
}

void
nsIMAPBodypartMultipart::SetBodySubType(char *bodySubType)
{
  PR_FREEIF(m_bodySubType);
  PR_FREEIF(m_contentType);
  m_bodySubType = bodySubType;
  if (m_bodyType && m_bodySubType)
    m_contentType = PR_smprintf("%s/%s", m_bodyType, m_bodySubType);
}


int32_t nsIMAPBodypartMultipart::Generate(nsIMAPBodyShell *aShell, bool stream, bool prefetch)
{
  int32_t len = 0;
  
  if (GetIsValid())
  {
    if (stream && !prefetch)
      aShell->GetConnection()->Log("SHELL","GENERATE-Multipart",m_partNumberString);
    
    // Stream out the MIME header of this part
    
    bool parentIsMessageType = GetParentPart() ? (GetParentPart()->GetType() == IMAP_BODY_MESSAGE_RFC822) : true;
    
    // If this is multipart/signed, then we always want to generate the MIME headers of this multipart.
    // Otherwise, we only want to do it if the parent is not of type "message"
    bool needMIMEHeader = !parentIsMessageType;  // !PL_strcasecmp(m_bodySubType, "signed") ? true : !parentIsMessageType;
    if (needMIMEHeader && !aShell->GetPseudoInterrupted())  // not a message body's type
    {
      len += GenerateMIMEHeader(aShell, stream, prefetch);
    }
    
    if (ShouldFetchInline(aShell))
    {
      for (size_t i = 0; i < m_partList->Length(); i++)
      {
        if (!aShell->GetPseudoInterrupted())
          len += GenerateBoundary(aShell, stream, prefetch, false);
        if (!aShell->GetPseudoInterrupted())
          len += m_partList->ElementAt(i)->Generate(aShell, stream, prefetch);
      }
      if (!aShell->GetPseudoInterrupted())
        len += GenerateBoundary(aShell, stream, prefetch, true);
    }
    else
    {
      // fill in the filling within the empty part
      if (!aShell->GetPseudoInterrupted())
        len += GenerateEmptyFilling(aShell, stream, prefetch);
    }
  }
  m_contentLength = len;
  return m_contentLength;
}


bool nsIMAPBodypartMultipart::ShouldFetchInline(nsIMAPBodyShell *aShell)
{
  char *generatingPart = aShell->GetGeneratingPart();
  if (generatingPart)
  {
    // If we are generating a specific part
    // Always generate containers (just don't fill them in)
    // because it is low cost (everything is cached)
    // and it gives the message its full MIME structure,
    // to avoid any potential mishap.
    return true;
  }
  else
  {
    // Generating whole message
    
    if (ShouldExplicitlyFetchInline())
      return true;
    if (ShouldExplicitlyNotFetchInline())
      return false;

    if (!PL_strcasecmp(m_bodySubType, "alternative"))
      return true;

    nsIMAPBodypart *grandparentPart = m_parentPart->GetParentPart();

    // if we're a multipart sub-part of multipart alternative, we need to 
    // be fetched because mime will always display us.
    if (!PL_strcasecmp(m_parentPart->GetBodySubType(), "alternative") &&
        GetType() == IMAP_BODY_MULTIPART)
      return true;
    // If "Show Attachments as Links" is on, and
    // the parent of this multipart is not a message,
    // then it's not inline.
    if (!(aShell->GetContentModified() == IMAP_CONTENT_MODIFIED_VIEW_INLINE) &&
      (m_parentPart->GetType() != IMAP_BODY_MESSAGE_RFC822) &&
      (m_parentPart->GetType() == IMAP_BODY_MULTIPART ?
      (grandparentPart ? grandparentPart->GetType() != IMAP_BODY_MESSAGE_RFC822 : true)
      : true))
      return false;
    
    // multiparts are always inline (even multipart/appledouble)
    // (their children might not be, though)
    return true;
  }
}

bool nsIMAPBodypartMultipart::PreflightCheckAllInline(nsIMAPBodyShell *aShell)
{
  bool rv = ShouldFetchInline(aShell);
  
  size_t i = 0;
  while (rv && (i < m_partList->Length()))
  {
    rv = m_partList->ElementAt(i)->PreflightCheckAllInline(aShell);
    i++;
  }
  
  return rv;
}

nsIMAPBodypart	*nsIMAPBodypartMultipart::FindPartWithNumber(const char *partNum)
{
  NS_ASSERTION(partNum, "null part passed into FindPartWithNumber");
  
  // check this
  if (!PL_strcmp(partNum, m_partNumberString))
    return this;
  
  // check children
  for (int i = m_partList->Length() - 1; i >= 0; i--)
  {
    nsIMAPBodypart *foundPart = m_partList->ElementAt(i)->FindPartWithNumber(partNum);
    if (foundPart)
      return foundPart;
  }
  
  // not this, or any of this's children
  return NULL;
}



///////////// nsIMAPMessageHeaders ////////////////////////////////////



nsIMAPMessageHeaders::nsIMAPMessageHeaders(char *partNum, nsIMAPBodypart *parentPart) : 
nsIMAPBodypart(partNum, parentPart)
{
  if (!partNum)
  {
    SetIsValid(false);
    return;
  }
  m_partNumberString = NS_strdup(partNum);
  if (!m_partNumberString)
  {
    SetIsValid(false);
    return;
  }
  if (!m_parentPart || !m_parentPart->GetnsIMAPBodypartMessage())
  {
    // Message headers created without a valid Message parent
    NS_ASSERTION(false, "creating message headers with invalid message parent");
    SetIsValid(false);
  }
}

nsIMAPBodypartType nsIMAPMessageHeaders::GetType()
{
  return IMAP_BODY_MESSAGE_HEADER;
}

void nsIMAPMessageHeaders::QueuePrefetchMessageHeaders(nsIMAPBodyShell *aShell)
{
  
  if (!m_parentPart->GetnsIMAPBodypartMessage()->GetIsTopLevelMessage())	// not top-level headers
    aShell->AddPrefetchToQueue(kRFC822HeadersOnly, m_partNumberString);
  else
    aShell->AddPrefetchToQueue(kRFC822HeadersOnly, NULL);
}

int32_t nsIMAPMessageHeaders::Generate(nsIMAPBodyShell *aShell, bool stream, bool prefetch)
{
  // prefetch the header
  if (prefetch && !m_partData && !aShell->DeathSignalReceived())
  {
    QueuePrefetchMessageHeaders(aShell);
  }
  
  if (stream && !prefetch)
    aShell->GetConnection()->Log("SHELL","GENERATE-MessageHeaders",m_partNumberString);
  
  // stream out the part data
  if (ShouldFetchInline(aShell))
  {
    if (!aShell->GetPseudoInterrupted())
      m_contentLength = GeneratePart(aShell, stream, prefetch);
  }
  else
  {
    m_contentLength = 0;	// don't fill in any filling for the headers
  }
  return m_contentLength;
}

bool nsIMAPMessageHeaders::ShouldFetchInline(nsIMAPBodyShell *aShell)
{
  return m_parentPart->ShouldFetchInline(aShell);
}


///////////// nsIMAPBodyShellCache ////////////////////////////////////

#if 0  // mscott - commenting out because it does not appear to be used
static int
imap_shell_cache_strcmp (const void *a, const void *b)
{
  return PL_strcmp ((const char *) a, (const char *) b);
}
#endif

nsIMAPBodyShellCache::nsIMAPBodyShellCache()
: m_shellHash(20)
{
  m_shellList = new nsTArray<nsIMAPBodyShell*>();
}

/* static */ nsIMAPBodyShellCache *nsIMAPBodyShellCache::Create()
{
  nsIMAPBodyShellCache *cache = new nsIMAPBodyShellCache();
  if (!cache || !cache->m_shellList)
    return NULL;
  
  return cache;
}

nsIMAPBodyShellCache::~nsIMAPBodyShellCache()
{
  while (EjectEntry()) ;
  delete m_shellList;
}

// We'll use an LRU scheme here.
// We will add shells in numerical order, so the
// least recently used one will be in slot 0.
bool nsIMAPBodyShellCache::EjectEntry()
{
  if (m_shellList->Length() < 1)
    return false;

  nsIMAPBodyShell *removedShell = m_shellList->ElementAt(0);

  m_shellList->RemoveElementAt(0);
  m_shellHash.Remove(removedShell->GetUID());

  return true;
}

void nsIMAPBodyShellCache::Clear()
{
  while (EjectEntry()) ;
}

bool nsIMAPBodyShellCache::AddShellToCache(nsIMAPBodyShell *shell)
{
  // If it's already in the cache, then just return.
  // This has the side-effect of re-ordering the LRU list
  // to put this at the top, which is good, because it's what we want.
  if (FindShellForUID(shell->GetUID(), shell->GetFolderName(), shell->GetContentModified()))
    return true;

  // OK, so it's not in the cache currently.

  // First, for safety sake, remove any entry with the given UID,
  // just in case we have a collision between two messages in different
  // folders with the same UID.
  RefPtr<nsIMAPBodyShell> foundShell;
  m_shellHash.Get(shell->GetUID(), getter_AddRefs(foundShell));
  if (foundShell)
  {
    m_shellHash.Remove(foundShell->GetUID());
    m_shellList->RemoveElement(foundShell);
  }

  // Add the new one to the cache
  m_shellList->AppendElement(shell);

  m_shellHash.Put(shell->GetUID(), shell);
  shell->SetIsCached(true);

  // while we're not over our size limit, eject entries
  bool rv = true;
  while (GetSize() > GetMaxSize())
    rv = EjectEntry();

  return rv;

}

nsIMAPBodyShell *nsIMAPBodyShellCache::FindShellForUID(nsCString &UID, const char *mailboxName,
                                                       IMAP_ContentModifiedType modType)
{
  RefPtr<nsIMAPBodyShell> foundShell;
  m_shellHash.Get(UID, getter_AddRefs(foundShell));
  if (!foundShell)
    return nullptr;
  // Make sure the content-modified types are compatible.
  // This allows us to work seamlessly while people switch between
  // View Attachments Inline and View Attachments As Links.
  // Enforce the invariant that any cached shell we use
  // match the current content-modified settings.
  if (modType != foundShell->GetContentModified())
    return nullptr;

  // mailbox names must match also.
  if (PL_strcmp(mailboxName, foundShell->GetFolderName()))
    return nullptr;

  // adjust the LRU stuff. This defeats the performance gain of the hash if
  // it actually is found since this is linear.
  m_shellList->RemoveElement(foundShell);
  m_shellList->AppendElement(foundShell);// Adds to end

  return foundShell;
}

///////////// nsIMAPMessagePartID ////////////////////////////////////


nsIMAPMessagePartID::nsIMAPMessagePartID(nsIMAPeFetchFields fields, const char *partNumberString)
: m_partNumberString(partNumberString),
  m_fields(fields)
{
}

nsIMAPMessagePartIDArray::nsIMAPMessagePartIDArray()
{
}

nsIMAPMessagePartIDArray::~nsIMAPMessagePartIDArray()
{
  RemoveAndFreeAll();
}

void nsIMAPMessagePartIDArray::RemoveAndFreeAll()
{
  uint32_t n = Length();
  for (uint32_t i = 0; i < n; i++)
  {
     nsIMAPMessagePartID *part = GetPart(i);
     delete part;
  }
  Clear();
}