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#include "msgCore.h"
#include "nsMsgSearchCore.h"
#include "nsMsgUtils.h"
#include "nsMsgBodyHandler.h"
#include "nsMsgSearchTerm.h"
#include "nsFileStream.h"
#include "nsIFileStream.h"
#include "nsIFileSpec.h"

nsMsgBodyHandler::nsMsgBodyHandler (nsIMsgSearchScopeTerm * scope, PRUint32 offset, PRUint32 numLines, nsIMsgDBHdr* msg, nsIMsgDatabase * db)
{
  m_scope = scope;
  m_localFileOffset = offset;
  m_numLocalLines = numLines;
  m_msgHdr = msg;
  m_db = db;
  
  // the following are variables used when the body handler is handling stuff from filters....through this constructor, that is not the
  // case so we set them to NULL.
  m_headers = NULL;
  m_headersSize = 0;
  m_Filtering = PR_FALSE; // make sure we set this before we call initialize...
  
  Initialize();  // common initialization stuff
  OpenLocalFolder();	    
}

nsMsgBodyHandler::nsMsgBodyHandler(nsIMsgSearchScopeTerm * scope,
                                   PRUint32 offset, PRUint32 numLines,
                                   nsIMsgDBHdr* msg, nsIMsgDatabase* db,
                                   const char * headers, PRUint32 headersSize,
                                   PRBool Filtering)
{
  m_scope = scope;
  m_localFileOffset = offset;
  m_numLocalLines = numLines;
  m_msgHdr = msg;
  m_db = db;
  m_headersSize = headersSize;
  m_Filtering = Filtering;
  
  Initialize();
  
  if (m_Filtering)
    m_headers = headers;
  else
    OpenLocalFolder();  // if nothing else applies, then we must be a POP folder file
}

void nsMsgBodyHandler::Initialize()
// common initialization code regardless of what body type we are handling...
{
  // Default transformations for local message search and MAPI access
  m_stripHeaders = PR_TRUE;
  m_stripHtml = PR_TRUE;
  m_messageIsHtml = PR_FALSE;
  m_passedHeaders = PR_FALSE;
  m_headerBytesRead = 0;
  
}

nsMsgBodyHandler::~nsMsgBodyHandler()
{
}

PRInt32 nsMsgBodyHandler::GetNextLine (nsCString &buf)
{
  PRInt32 length = 0;
  PRBool eatThisLine = PR_FALSE;
  
  do {
    // first, handle the filtering case...this is easy....
    if (m_Filtering)
      length = GetNextFilterLine(buf);
    else
    {
      // 3 cases: Offline IMAP, POP, or we are dealing with a news message....
      // Offline cases should be same as local mail cases, since we're going
      // to store offline messages in berkeley format folders.
      if (m_db)
      {
         length = GetNextLocalLine (buf); // (2) POP
      }
    }
    
    if (length >= 0)
      length = ApplyTransformations (buf, length, eatThisLine);
  } while (eatThisLine && length >= 0);  // if we hit eof, make sure we break out of this loop. Bug #:
  return length;  
}

void nsMsgBodyHandler::OpenLocalFolder()
{
  nsCOMPtr <nsIInputStream> inputStream;
  nsresult rv = m_scope->GetInputStream(getter_AddRefs(inputStream));
  if (NS_SUCCEEDED(rv))
  {
    nsCOMPtr <nsISeekableStream> seekableStream = do_QueryInterface(inputStream);
    seekableStream->Seek(PR_SEEK_SET, m_localFileOffset);
  }
  m_fileLineStream = do_QueryInterface(inputStream);
}

PRInt32 nsMsgBodyHandler::GetNextFilterLine(nsCString &buf)
{
  // m_nextHdr always points to the next header in the list....the list is NULL terminated...
  PRUint32 numBytesCopied = 0;
  if (m_headersSize > 0)
  {
    // #mscott. Ugly hack! filter headers list have CRs & LFs inside the NULL delimited list of header
    // strings. It is possible to have: To NULL CR LF From. We want to skip over these CR/LFs if they start
    // at the beginning of what we think is another header.
    
    while (m_headersSize > 0 && (m_headers[0] == nsCRT::CR || m_headers[0] == nsCRT::LF || m_headers[0] == ' ' || m_headers[0] == '\0'))
    {
      m_headers++;  // skip over these chars...
      m_headersSize--;
    }
    
    if (m_headersSize > 0)
    {
      numBytesCopied = strlen(m_headers) + 1 ;
      buf.Assign(m_headers);
      m_headers += numBytesCopied;  
      // be careful...m_headersSize is unsigned. Don't let it go negative or we overflow to 2^32....*yikes*	
      if (m_headersSize < numBytesCopied)
        m_headersSize = 0;
      else
        m_headersSize -= numBytesCopied;  // update # bytes we have read from the headers list
      
      return (PRInt32) numBytesCopied;
    }
  }
  else if (m_headersSize == 0) {
    buf.Truncate();
  }
  return -1;
}

// return -1 if no more local lines, length of next line otherwise.

PRInt32 nsMsgBodyHandler::GetNextLocalLine(nsCString &buf)
// returns number of bytes copied
{
  if (m_numLocalLines)
  {
    if (m_passedHeaders)
      m_numLocalLines--; // the line count is only for body lines
    // do we need to check the return value here?
    if (m_fileLineStream)
    {
      PRBool more = PR_FALSE;
      nsresult rv = m_fileLineStream->ReadLine(buf, &more);
      if (NS_SUCCEEDED(rv))
        return buf.Length();
    }
  }
  
  return -1;
}

PRInt32 nsMsgBodyHandler::ApplyTransformations (nsCString &buf, PRInt32 length, PRBool &eatThisLine)
{
  PRInt32 newLength = length;
  eatThisLine = PR_FALSE;
  
  if (!m_passedHeaders)	// buf is a line from the message headers
  {
    if (m_stripHeaders)
      eatThisLine = PR_TRUE;
    
    if (StringBeginsWith(buf, NS_LITERAL_CSTRING("Content-Type:")) && FindInReadable(buf, NS_LITERAL_CSTRING("text/html")))
      m_messageIsHtml = PR_TRUE;
    
    m_passedHeaders = buf.IsEmpty() || buf.First() == nsCRT::CR || buf.First() == nsCRT::LF;
  }
  else	// buf is a line from the message body
  {
    if (m_stripHtml && m_messageIsHtml)
    {
      StripHtml (buf);
      newLength = buf.Length();
    }
  }
  
  return newLength;
}

void nsMsgBodyHandler::StripHtml (nsCString &pBufInOut)
{
  char *pBuf = (char*) PR_Malloc (pBufInOut.Length() + 1);
  if (pBuf)
  {
    char *pWalk = pBuf;
    
    char *pWalkInOut = (char *) pBufInOut.get();
    PRBool inTag = PR_FALSE;
    while (*pWalkInOut) // throw away everything inside < >
    {
      if (!inTag)
        if (*pWalkInOut == '<')
          inTag = PR_TRUE;
        else
          *pWalk++ = *pWalkInOut;
        else
          if (*pWalkInOut == '>')
            inTag = PR_FALSE;
          pWalkInOut++;
    }
    *pWalk = 0; // null terminator
    
    pBufInOut.Adopt(pBuf);
  }
}