/* GNU Mailutils -- a suite of utilities for electronic mail
   Copyright (C) 1999-2002, 2004-2005, 2007, 2009-2012, 2014-2016 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, see <http://www.gnu.org/licenses/>. */

#include "maidag.h"

#if defined (USE_MAILBOX_QUOTAS)

#define DEFRETVAL MQUOTA_UNLIMITED

mu_off_t groupquota = 5*1024*1024UL;
static int get_size (char *, mu_off_t *, char **);

int
get_size (char *str, mu_off_t *size, char **endp)
{
  mu_off_t s;

  s = strtol (str, &str, 0);
  switch (*str)
    {
    case 0:
      break;
      
    case 'k':
    case 'K':
      s *= 1024;
      break;
      
    case 'm':
    case 'M':
      s *= 1024*1024;
      break;
      
    default:
      *endp = str;
      return -1;
    }
  *size = s;
  return 0;
}

#define RETR_OK        0
#define RETR_UNLIMITED -1
#define RETR_FAILURE   1

int
fail_retrieve_quota (char *name, mu_off_t *quota)
{
  mu_error (_("no quota retrieving mechanism"));
  return RETR_FAILURE;
}

#ifdef ENABLE_DBM
int
dbm_retrieve_quota (char *name, mu_off_t *quota)
{
  mu_dbm_file_t db;
  struct mu_dbm_datum  named, contentd;
  char buffer[64];
  int unlimited = 0;
  int rc;

  if (!quotadbname)
    return RETR_FAILURE;

  rc = mu_dbm_create (quotadbname, &db, MU_FILE_SAFETY_ALL);
  if (rc)
    {
      mu_error (_("unable to create quota db"));
      return RETR_FAILURE;
    }

  rc = mu_dbm_safety_check (db);
  if (rc && rc != ENOENT)
    {
      mu_error (_("quota db fails safety check: %s"),
		mu_strerror (rc));
      mu_dbm_destroy (&db);
      return RETR_FAILURE;
    }

  rc = mu_dbm_open (db, MU_STREAM_READ, 0600);
  if (rc)
    {
      mu_error (_("cannot open file %s: %s"),
		quotadbname, mu_strerror (rc));
      mu_dbm_destroy (&db);
      return RETR_FAILURE;
    }
  
  memset (&named, 0, sizeof named);
  memset (&contentd, 0, sizeof contentd);
  named.mu_dptr = name;
  named.mu_dsize = strlen (name);
  rc = mu_dbm_fetch (db, &named, &contentd);
  if (rc)
    {
      /* User not in database, try default quota */
      mu_dbm_datum_free (&named);
      named.mu_dptr = "DEFAULT";
      named.mu_dsize = strlen ("DEFAULT");
      rc = mu_dbm_fetch (db, &named, &contentd);
      if (rc == MU_ERR_NOENT)
	{
	  mu_dbm_destroy (&db);
	  return RETR_FAILURE;
	}
      else if (rc)
	{
	  mu_error (_("can't fetch data: %s"), mu_dbm_strerror (db));
	  mu_dbm_destroy (&db);
	  return RETR_FAILURE;
	}
    }

  if (mu_c_strncasecmp("none", contentd.mu_dptr, contentd.mu_dsize) == 0) 
      unlimited = 1;
  else if (contentd.mu_dsize > sizeof (buffer) - 1)
    {
      mu_error (ngettext ("mailbox quota for `%s' is too big: %lu digit",
			  "mailbox quota for `%s' is too big: %lu digits",
			  contentd.mu_dsize),
		name, (unsigned long) contentd.mu_dsize);
      *quota = groupquota;
    }
  else
    {
      char *p;
		
      strncpy (buffer, contentd.mu_dptr, contentd.mu_dsize);
      buffer[contentd.mu_dsize] = 0;
      *quota = strtoul (buffer, &p, 0);
      if (get_size (buffer, quota, &p))
	{
	  mu_error (_("bogus mailbox quota for `%s' (near `%s')"), name, p);
	  *quota = groupquota;
	}
    }
  
  mu_dbm_datum_free (&contentd);
  mu_dbm_destroy (&db);
  
  return unlimited ? RETR_UNLIMITED : RETR_OK;
}

# define default_retrieve_quota dbm_retrieve_quota
#else
# define default_retrieve_quota fail_retrieve_quota
#endif

#ifdef USE_SQL
#include <mailutils/sql.h>

/* FIXME: defined in libmu_auth/sql.c */
#include <libmu_auth/sql.h>

int
sql_retrieve_quota (char *name, mu_off_t *quota)
{
  mu_sql_connection_t conn;
  char *query_str;
  int rc, status;
  char *tmp;
  size_t n;
  
  query_str = mu_sql_expand_query (quota_query, name);
  if (!query_str)
    return RETR_FAILURE;

  status = mu_sql_connection_init (&conn,
				   mu_sql_module_config.interface,
				   mu_sql_module_config.host,
				   mu_sql_module_config.port,
				   mu_sql_module_config.user,
				   mu_sql_module_config.passwd,
				   mu_sql_module_config.db);
  
  if (status)
    {
      mu_error ("%s. SQL error: %s",
		mu_strerror (status), mu_sql_strerror (conn));
      mu_sql_connection_destroy (&conn);
      free (query_str);
      return RETR_FAILURE;
    }

  status = mu_sql_connect (conn);

  if (status)
    {
      mu_error ("%s. SQL error: %s",
		mu_strerror (status), mu_sql_strerror (conn));
      mu_sql_connection_destroy (&conn);
      free (query_str);
      return  RETR_FAILURE;
    }
  
  status = mu_sql_query (conn, query_str);
  free (query_str);
  
  if (status)
    {
      mu_error (_("SQL query failed: %s"),
		(status == MU_ERR_SQL) ?  mu_sql_strerror (conn) :
	 	                          mu_strerror (status));
      mu_sql_connection_destroy (&conn);
      return  RETR_FAILURE;
    }

  status = mu_sql_store_result (conn);

  if (status)
    {
      mu_error (_("cannot store SQL result: %s"),
		(status == MU_ERR_SQL) ?  mu_sql_strerror (conn) :
	 	                          mu_strerror (status));
      mu_sql_connection_destroy (&conn);
      return RETR_FAILURE;
    }

  mu_sql_num_tuples (conn, &n);
  if (n == 0)
    {
      rc = RETR_FAILURE;
    }
  else
    {
      rc = RETR_OK;
      tmp = NULL;
      status = mu_sql_get_column (conn, 0, 0, &tmp);
      if (status)
	{
	  mu_error (_("cannot retrieve mailbox quota from SQL: %s"),
		    (status == MU_ERR_SQL) ?  mu_sql_strerror (conn) :
		    mu_strerror (status));
	  rc = RETR_FAILURE;
	}
      else if (tmp == NULL || tmp[0] == 0 || mu_c_strcasecmp (tmp, "none") == 0)
	rc = RETR_UNLIMITED;
      else
	{
	  char *p;
	  
	  if (get_size (tmp, quota, &p))
	    {
	      mu_error (_("bogus mailbox quota for `%s' (near `%s')"),
			name, p);
	      *quota = groupquota;
	    }
	}
    }
  
  mu_sql_release_result (conn);
  mu_sql_disconnect (conn);
  mu_sql_connection_destroy (&conn);
  return rc;
}
#endif


static int
retrieve_quota (struct mu_auth_data *auth, mu_off_t *quota)
{
  if (MU_HAS_QUOTA (auth))
    {
      if (auth->quota == 0)
	return RETR_UNLIMITED;
      *quota = auth->quota;
      return RETR_OK;
    }
  
#ifdef USE_SQL
  if (quota_query)
    return sql_retrieve_quota (auth->name, quota);
#endif
  return default_retrieve_quota (auth->name, quota);
}

int
check_quota (struct mu_auth_data *auth, mu_off_t size, mu_off_t *rest)
{
  mu_off_t quota;

  if (!auth)
    return MQUOTA_OK;
  
  switch (retrieve_quota (auth, &quota))
    {
    case RETR_FAILURE:
      return DEFRETVAL;
      
    case RETR_UNLIMITED:
      return MQUOTA_UNLIMITED;

    case RETR_OK:
      if (quota < size)  /* Mailbox full */
	return MQUOTA_EXCEEDED;
	
      if (rest)
	*rest = quota - size;
    }
  
  return MQUOTA_OK;
}
  
#endif /* USE_MAIL_QUOTA */