/* GNU Mailutils -- a suite of utilities for electronic mail
   Copyright (C) 1999, 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010
   Free Software Foundation, Inc.

   GNU Mailutils is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3, or (at your option)
   any later version.

   GNU Mailutils is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with GNU Mailutils; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301 USA */

#include "pop3d.h"
#include "mailutils/libargp.h"

mu_stream_t iostream;

void
pop3d_parse_command (char *cmd, char **pcmd, char **parg)
{
  char *p;
  
  cmd = mu_str_skip_class (cmd, MU_CTYPE_BLANK);
  *pcmd = cmd;
  p = mu_str_skip_class_comp (cmd, MU_CTYPE_SPACE);
  *p++ = 0;
  if (*p)
    {
      *parg = p;
      mu_rtrim_class (p, MU_CTYPE_SPACE);
    }
  else
    *parg = "";
}

/* This is called if GNU POP3 needs to quit without going to the UPDATE stage.
   This is used for conditions such as out of memory, a broken socket, or
   being killed on a signal */
int
pop3d_abquit (int reason)
{
  int code;
  
  /* Unlock spool */
  if (state != AUTHORIZATION)
    {
      pop3d_unlock ();
      mu_mailbox_flush (mbox, 0);
      mu_mailbox_close (mbox);
      mu_mailbox_destroy (&mbox);
    }

  switch (reason)
    {
    case ERR_NO_MEM:
      code = EX_SOFTWARE;
      pop3d_outf ("-ERR %s\n", pop3d_error_string (reason));
      mu_diag_output (MU_DIAG_ERROR, _("not enough memory"));
      break;

    case ERR_SIGNAL:
      code = EX_SOFTWARE;
      mu_diag_output (MU_DIAG_ERROR, _("quitting on signal"));
      break;

    case ERR_TERMINATE:
      code = EX_OK;
      mu_diag_output (MU_DIAG_NOTICE, _("terminating on request"));
      break;

    case ERR_TIMEOUT:
      code = EX_TEMPFAIL;
      pop3d_outf ("-ERR %s\n", pop3d_error_string (reason));
      if (state == TRANSACTION)
	mu_diag_output (MU_DIAG_INFO, _("session timed out for user: %s"),
			username);
      else
	mu_diag_output (MU_DIAG_INFO, _("session timed out for no user"));
      break;

    case ERR_NO_IFILE:
      code = EX_NOINPUT;
      mu_diag_output (MU_DIAG_INFO, _("no input stream"));
      break;

    case ERR_NO_OFILE:
      code = EX_IOERR;
      mu_diag_output (MU_DIAG_INFO, _("no socket to send to"));
      break;

    case ERR_PROTO:
      code = EX_PROTOCOL;
      mu_diag_output (MU_DIAG_INFO, _("remote protocol error"));
      break;

    case ERR_IO:
      code = EX_IOERR;
      mu_diag_output (MU_DIAG_INFO, _("I/O error"));
      break;

    case ERR_MBOX_SYNC:
      code = EX_OSERR; /* FIXME: This could be EX_SOFTWARE as well? */
      mu_diag_output (MU_DIAG_ERROR,
		      _("mailbox was updated by other party: %s"),
		      username);
      pop3d_outf
	("-ERR [OUT-SYNC] Mailbox updated by other party or corrupt\n");
      break;

    default:
      code = EX_SOFTWARE;
      pop3d_outf ("-ERR Quitting: %s\n", pop3d_error_string (reason));
      mu_diag_output (MU_DIAG_ERROR, _("quitting (numeric reason %d)"),
		      reason);
      break;
    }

  closelog ();
  exit (code);
}

void
pop3d_setio (FILE *in, FILE *out)
{
  mu_stream_t str, istream, ostream;
  
  if (!in)
    pop3d_abquit (ERR_NO_IFILE);
  if (!out)
    pop3d_abquit (ERR_NO_OFILE);

  if (mu_stdio_stream_create (&istream, fileno (in), 
                              MU_STREAM_READ | MU_STREAM_AUTOCLOSE))
    pop3d_abquit (ERR_NO_IFILE);
  mu_stream_set_buffer (istream, mu_buffer_line, 1024);
  
  if (mu_stdio_stream_create (&ostream, fileno (out), 
                              MU_STREAM_WRITE | MU_STREAM_AUTOCLOSE))
    pop3d_abquit (ERR_NO_OFILE);

  /* Combine the two streams into an I/O one. */
  if (mu_iostream_create (&str, istream, ostream))
    pop3d_abquit (ERR_FILE);

  /* Convert all writes to CRLF form.
     There is no need to convert reads, as the code ignores extra \r anyway.
     This also installs an extra full buffering, which is needed for TLS
     code (see below). */
  if (mu_filter_create (&iostream, str, "rfc822", MU_FILTER_ENCODE,
			MU_STREAM_WRITE | MU_STREAM_RDTHRU))
    pop3d_abquit (ERR_NO_IFILE);
  
  if (pop3d_transcript)
    {
      int rc;
      mu_debug_t debug;
      mu_stream_t dstr, xstr;
      
      mu_diag_get_debug (&debug);
      
      rc = mu_dbgstream_create (&dstr, debug, MU_DIAG_DEBUG, 0);
      if (rc)
	mu_error (_("cannot create debug stream; transcript disabled: %s"),
		  mu_strerror (rc));
      else
	{
	  rc = mu_xscript_stream_create (&xstr, iostream, dstr, NULL);
	  if (rc)
	    mu_error (_("cannot create transcript stream: %s"),
		      mu_strerror (rc));
	  else
	    {
	      mu_stream_unref (iostream);
	      iostream = xstr;
	    }
	}
    }
}

#ifdef WITH_TLS
int
pop3d_init_tls_server ()
{
  mu_stream_t tlsstream, stream[2];
  int rc;

  stream[0] = stream[1] = NULL;
  rc = mu_stream_ioctl (iostream, MU_IOCTL_SWAP_STREAM, stream);
  if (rc)
    {
      mu_error (_("%s failed: %s"), "MU_IOCTL_SWAP_STREAM",
		mu_stream_strerror (iostream, rc));
      return 1;
    }
  
  rc = mu_tls_server_stream_create (&tlsstream, stream[0], stream[1], 0);
  if (rc)
    return 1;

  rc = mu_stream_open (tlsstream);
  if (rc)
    {
      mu_diag_output (MU_DIAG_ERROR, _("cannot open TLS stream: %s"),
		      mu_stream_strerror (tlsstream, rc));
      mu_stream_destroy (&tlsstream);
      return 1;
    }
  else
    stream[0] = stream[1] = tlsstream;

  rc = mu_stream_ioctl (iostream, MU_IOCTL_SWAP_STREAM, stream);
  if (rc)
    {
      mu_error (_("%s failed: %s"), "MU_IOCTL_SWAP_STREAM",
		mu_stream_strerror (iostream, rc));
      pop3d_abquit (ERR_IO);
    }
  return 0;
}
#endif

void
pop3d_bye ()
{
  mu_stream_close (iostream);
  mu_stream_destroy (&iostream);
#ifdef WITH_TLS
  if (tls_available)
    mu_deinit_tls_libs ();
#endif /* WITH_TLS */
}

void
pop3d_flush_output ()
{
  mu_stream_flush (iostream);
}

int
pop3d_is_master ()
{
  return iostream == NULL;
}

void
pop3d_outf (const char *fmt, ...)
{
  va_list ap;
  int rc;
  
  va_start (ap, fmt);
  rc = mu_stream_vprintf (iostream, fmt, ap);
  va_end (ap);
  if (rc)
    {
      mu_diag_output (MU_DIAG_ERROR, _("Write failed: %s"),
 		      mu_stream_strerror (iostream, rc));
      pop3d_abquit (ERR_IO);
    }
}

/* Gets a line of input from the client, caller should free() */
char *
pop3d_readline (char *buffer, size_t size)
{
  int rc;
  size_t nbytes;
  
  alarm (idle_timeout);
  rc = mu_stream_readline (iostream, buffer, size, &nbytes);
  alarm (0);

  if (rc)
    {
      mu_diag_output (MU_DIAG_ERROR, _("Read failed: %s"),
 		      mu_stream_strerror (iostream, rc));
      pop3d_abquit (ERR_IO);
    }
  else if (nbytes == 0)
    {
      /* After a failed authorization attempt many clients simply disconnect
	 without issuing QUIT. We do not count this as a protocol error. */
      if (state == AUTHORIZATION)
	exit (EX_OK);

      mu_diag_output (MU_DIAG_ERROR, _("Unexpected eof on input"));
      pop3d_abquit (ERR_PROTO);
    }

  return buffer;
}


/* Handling of the deletion marks */

void
pop3d_mark_deleted (mu_attribute_t attr)
{
  mu_attribute_set_userflag (attr, POP3_ATTRIBUTE_DELE);
}

int
pop3d_is_deleted (mu_attribute_t attr)
{
  return mu_attribute_is_deleted (attr)
         || mu_attribute_is_userflag (attr, POP3_ATTRIBUTE_DELE);
}

void
pop3d_unset_deleted (mu_attribute_t attr)
{
  if (mu_attribute_is_userflag (attr, POP3_ATTRIBUTE_DELE))
    mu_attribute_unset_userflag (attr, POP3_ATTRIBUTE_DELE);
}

void
pop3d_undelete_all ()
{
  size_t i;
  size_t total = 0;

  mu_mailbox_messages_count (mbox, &total);

  for (i = 1; i <= total; i++)
    {
       mu_message_t msg = NULL;
       mu_attribute_t attr = NULL;
       mu_mailbox_get_message (mbox, i, &msg);
       mu_message_get_attribute (msg, &attr);
       mu_attribute_unset_deleted (attr);
    }
}