/**
 *  @file operator-copy.cc
 *  @brief Implementation of the COPY command.
 *  @author Andreas Aardal Hanssen
 *  @date 2002-2005
 */

#include "convert.h"
#include "depot.h"
#include "iodevice.h"
#include "iofactory.h"
#include "maildir.h"
#include "operators.h"
#include "recursivedescent.h"
#include "session.h"

#include <string>

using namespace Binc;
using std::string;

CopyOperator::CopyOperator() {}

CopyOperator::~CopyOperator() {}

const string CopyOperator::getName() const
{
  return "COPY";
}

Session::State CopyOperator::getState() const
{
  return Session::SELECTED;
}

Operator::ProcessResult CopyOperator::process(Depot &depot, Request &command)
{
  Session &session = Session::getInstance();

  // Get the current mailbox
  Mailbox *srcMailbox = depot.getSelected();

  // Get the destination mailbox
  string dmailbox = command.getMailbox();
  Mailbox *destMailbox = depot.get(toCanonMailbox(dmailbox));
  if (destMailbox == nullptr) {
    session.setResponseCode("TRYCREATE");
    session.setLastError("invalid mailbox " + toImapString(dmailbox));
    return Operator::ProcessResult::NO;
  }

  unsigned int mode = Mailbox::SKIP_EXPUNGED;
  mode |= command.getUidMode() ? Mailbox::UID_MODE : Mailbox::SQNR_MODE;

  // Copy each message in the sequence set to the destination mailbox.
  bool success = true;
  Mailbox::iterator i = srcMailbox->begin(command.bset, mode);
  for (; success && i != srcMailbox->end(); ++i) {
    Message &source = *i;

    if (srcMailbox->fastCopy(source,
                             *destMailbox,
                             depot.mailboxToFilename(toCanonMailbox(dmailbox))))
      continue;

    // Have the destination mailbox create a message for us.
    Message *dest = destMailbox->createMessage(
        depot.mailboxToFilename(toCanonMailbox(dmailbox)),
        source.getInternalDate());
    if (!dest) {
      session.setLastError(destMailbox->getLastError());
      success = false;
      break;
    }

    // Set the flags and internal date.
    dest->setStdFlag(source.getStdFlags());
    dest->setInternalDate(source.getInternalDate());

    // Copy chunks from the source message over to the destination
    // message.
    string chunk;
    do {
      int readSize = source.readChunk(chunk);

      if (readSize == 0) {
        break;
      } else if (readSize == -1) {
        bincWarning << "when reading from message " << i.getSqnr() << "/" << source.getUID()
                    << " in \"" << srcMailbox->getName() << "\": " << source.getLastError()
                    << std::endl;
        success = false;
      } else if (!dest->appendChunk(chunk)) {
        bincWarning << "when writing to \"" << dmailbox << "\": " << dest->getLastError()
                    << std::endl;
        success = false;
      }
    } while (success);

    dest->close();
  }

  if (!success && !destMailbox->rollBackNewMessages()) {
    session.setLastError("Failed to rollback after unsuccessful copy: "
                         + destMailbox->getLastError());
    return Operator::ProcessResult::NO;
  }

  if (success) {
    if (!destMailbox->commitNewMessages(depot.mailboxToFilename(toCanonMailbox(dmailbox)))) {
      session.setLastError("Failed to commit after successful copy: "
                           + destMailbox->getLastError());
      return Operator::ProcessResult::NO;
    }
  }

  if (!success) {
    session.setLastError("The transaction was unrolled. Please "
                         "contant your system administrator for "
                         "more information.");
  }

  return success ? Operator::ProcessResult::OK : Operator::ProcessResult::NO;
}

Parser::ParseResult CopyOperator::parse(Request &c_in)
{
  constexpr auto ACCEPT = Parser::ParseResult::ACCEPT;

  Session &session = Session::getInstance();

  Parser::ParseResult res;
  if ((res = expectSPACE()) != ACCEPT) {
    session.setLastError("Expected SPACE after COPY");
    return res;
  }

  if ((res = expectSet(c_in.getSet())) != ACCEPT) {
    session.setLastError("Expected sequence set after COPY SPACE");
    return res;
  }

  if ((res = expectSPACE()) != ACCEPT) {
    session.setLastError("Expected SPACE after COPY SPACE set");
    return res;
  }

  string mailbox;
  if ((res = expectMailbox(mailbox)) != ACCEPT) {
    session.setLastError("Expected mailbox after COPY SPACE set SPACE");
    return res;
  }

  if ((res = expectCRLF()) != ACCEPT) {
    session.setLastError("Expected CRLF after COPY SPACE set SPACE mailbox");
    return res;
  }

  c_in.setMailbox(mailbox);
  c_in.setName("COPY");

  return ACCEPT;
}