/*
 * config_auth.c :  authentication files in the user config area
 *
 * ====================================================================
 * Copyright (c) 2000-2004 CollabNet.  All rights reserved.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution.  The terms
 * are also available at http://subversion.tigris.org/license-1.html.
 * If newer versions of this license are posted there, you may use a
 * newer version instead, at your option.
 *
 * This software consists of voluntary contributions made by many
 * individuals.  For exact contribution history, see the revision
 * history and logs, available at http://subversion.tigris.org/.
 * ====================================================================
 */



#include <apr_md5.h>

#include "svn_path.h"
#include "svn_md5.h"
#include "svn_hash.h"
#include "svn_io.h"

#include "config_impl.h"

#include "svn_private_config.h"

/* Helper for svn_config_{read|write}_auth_data.  Return a path to a
   file within ~/.subversion/auth/ that holds CRED_KIND credentials
   within REALMSTRING.  If no path is available *PATH will be set to
   NULL. */
static svn_error_t *
auth_file_path (const char **path,
                const char *cred_kind,
                const char *realmstring,
                const char *config_dir,
                apr_pool_t *pool)
{
  const char *authdir_path, *hexname;
  unsigned char digest[APR_MD5_DIGESTSIZE];
      
  /* Construct the path to the directory containing the creds files,
     e.g. "~/.subversion/auth/svn.simple".  The last component is
     simply the cred_kind.  */
  SVN_ERR (svn_config__user_config_path (config_dir, &authdir_path,
                                         SVN_CONFIG__AUTH_SUBDIR, pool));
  if (authdir_path)
    {
      authdir_path = svn_path_join (authdir_path, cred_kind, pool);

      /* Construct the basename of the creds file.  It's just the
         realmstring converted into an md5 hex string.  */
      apr_md5 (digest, realmstring, strlen(realmstring));
      hexname = svn_md5_digest_to_cstring (digest, pool);

      *path = svn_path_join (authdir_path, hexname, pool);
    }
  else
    *path = NULL;

  return SVN_NO_ERROR;
}


svn_error_t *
svn_config_read_auth_data (apr_hash_t **hash,
                           const char *cred_kind,
                           const char *realmstring,
                           const char *config_dir,
                           apr_pool_t *pool)
{
  svn_node_kind_t kind;
  const char *auth_path;

  *hash = NULL;

  SVN_ERR (auth_file_path (&auth_path, cred_kind, realmstring, config_dir,
                           pool));
  if (! auth_path)
    return SVN_NO_ERROR;

  SVN_ERR (svn_io_check_path (auth_path, &kind, pool));
  if (kind == svn_node_file)
    {
      apr_file_t *authfile = NULL;

      SVN_ERR_W (svn_io_file_open (&authfile, auth_path,
                                   APR_READ | APR_BUFFERED, APR_OS_DEFAULT,
                                   pool),
                 _("Unable to open auth file for reading"));
      
      *hash = apr_hash_make (pool);

      SVN_ERR_W (svn_hash_read (*hash, authfile, pool),
                 apr_psprintf (pool, _("Error parsing '%s'"),
                               svn_path_local_style (auth_path, pool)));
      
      SVN_ERR (svn_io_file_close (authfile, pool));
    }

  return SVN_NO_ERROR;
}


svn_error_t *
svn_config_write_auth_data (apr_hash_t *hash,
                            const char *cred_kind,
                            const char *realmstring,
                            const char *config_dir,
                            apr_pool_t *pool)
{
  apr_file_t *authfile = NULL;
  const char *auth_path;

  SVN_ERR (auth_file_path (&auth_path, cred_kind, realmstring, config_dir,
                           pool));
  if (! auth_path)
    return svn_error_create (SVN_ERR_NO_AUTH_FILE_PATH, NULL,
                             _("Unable to locate auth file"));

  /* Add the realmstring to the hash, so programs (or users) can
     verify exactly which set of credentials this file holds.  */
  apr_hash_set (hash, SVN_CONFIG_REALMSTRING_KEY, APR_HASH_KEY_STRING,
                svn_string_create (realmstring, pool));

  SVN_ERR_W (svn_io_file_open (&authfile, auth_path,
                               (APR_WRITE | APR_CREATE | APR_TRUNCATE
                                | APR_BUFFERED),
                               APR_OS_DEFAULT, pool),
             _("Unable to open auth file for writing"));
  
  SVN_ERR_W (svn_hash_write (hash, authfile, pool),
             apr_psprintf (pool, _("Error writing hash to '%s'"),
                           svn_path_local_style (auth_path, pool)));

  SVN_ERR (svn_io_file_close (authfile, pool));

  /* To be nice, remove the realmstring from the hash again, just in
     case the caller wants their hash unchanged. */
  apr_hash_set (hash, SVN_CONFIG_REALMSTRING_KEY, APR_HASH_KEY_STRING, NULL);

  return SVN_NO_ERROR;
}
